Management Techniques for Laboratories and Other Small Institutional Generators to Minimize Off-Site Disposal of Low-Level Radioactive Waste

NCRP REPORT No. 143

MANAGEMENT TECHNIQUES FOR LABORATORIES AND OTHER SMALL INSTITUTIONAL GENERATORS TO MINIMIZE OFF-SITE DISPOSAL OF LOWLEVEL RADIOACTIVE WASTE

N C R P

National Council on Radiation Protection and Measurements

NCRP REPORT No. 143

Management Techniques for Laboratories and Other Small Institutional Generators to Minimize Off-Site Disposal of LowLevel Radioactive Waste Recommendations of the NATIONAL COUNCIL ON RADIATION PROTECTION AND MEASUREMENTS

Issued April 18, 2003

National Council on Radiation Protection and Measurements 7910 Woodmont Avenue, Suite 400 / Bethesda, MD 20814

LEGAL NOTICE This Report was prepared by the National Council on Radiation Protection and Measurements (NCRP). The Council strives to provide accurate, complete and useful information in its documents. However, neither the NCRP, the members of NCRP, other persons contributing to or assisting in the preparation of this Report, nor any person acting on the behalf of any of these parties: (a) makes any warranty or representation, express or implied, with respect to the accuracy, completeness or usefulness of the information contained in this Report, or that the use of any information, method or process disclosed in this Report may not infringe on privately owned rights; or (b) assumes any liability with respect to the use of, or for damages resulting from the use of any information, method or process disclosed in this Report, under the Civil Rights Act of 1964, Section 701 et seq. as amended 42 U.S.C. Section 2000e et seq. (Title VII) or any other statutory or common law theory governing liability.

Library of Congress Cataloging-in-Publication Data National Council on Radiation Protection and Measurements. Management techniques for laboratories and other small institutional generators to minimize off-site disposal of low-level radioactive waste / recommendations of the National Council on Radiation Protection and Measurements. p. cm. — (NCRP report ; no. 143) Includes bibliographical references and index. ISBN 0-929600-76-2 1. Radioactive wastes—United States—Management. 2. Low-level radiation— United States. 3. Waste minimization—United States. I. Title. II. Series TD898.118.N35 2003 621.48'38'0973--dc21

2003042138

Copyright © National Council on Radiation Protection and Measurements 2003 All rights reserved. This publication is protected by copyright. No part of this publication may be reproduced in any form or by any means, including photocopying, or utilized by any information storage and retrieval system without written permission from the copyrightowner, except for brief quotation in critical articles or reviews. [For detailed information on the availability of NCRP publications see page 216.]

Preface In recognition of the social and economic costs associated with the storage and deposition of radioactive waste, the Scientific Program Area Committee of the National Council on Radiation Protection and Measurements (NCRP) on Radioactive and Mixed Waste recommended that a scientific report be developed with the aim of minimizing the amount of waste generated. As a result, this Report was prepared by NCRP Scientific Committee 87-1 on Waste Avoidance and Volume Reduction. NCRP wishes to thank the U.S. Department of Energy for their financial support, in part, of this Report. Serving on Scientific Committee 87-1 were:

Chairman William P. Dornsife Harrisburg, Pennsylvania Members Russell S. Garcia EG&G Idaho, Inc. Idaho Falls, Idaho

Edward H. Rau National Institutes of Health U.S. Department of Health and Human Services Bethesda, Maryland

Francis X. Masse Massachusetts Institute of Technology Bates Linac Middleton, Massachusetts

Anthony Wolbarst U.S. Environmental Protection Agency Washington, D.C.

John Psaras U.S. Department of Energy Washington, D.C.

Consultant Walter Hipsher Oak Ridge, Tennessee iii

iv / PREFACE NCRP Secretariat E. Ivan White, Senior Staff Scientist Cindy L. O’Brien, Managing Editor The Council wishes to express its appreciation to the Committee members for the time and effort devoted to the preparation of this Report.

Thomas S. Tenforde President

Contents Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii 1. Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.1 Purpose. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.2 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.3 Common Terms Used in this Report . . . . . . . . . . . . . . . 7 2.4 Hierarchy of Waste Minimization Steps . . . . . . . . . . . . 9 2.5 Scope of this Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 2.6 Organization of this Report. . . . . . . . . . . . . . . . . . . . . . . 11 2.7 A Guide for Implementing an Effective Waste Minimization Program . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.7.1 Waste Minimization Planning. . . . . . . . . . . . . . . 13 2.7.2 Program Goals and Evaluation . . . . . . . . . . . . . . 15 2.7.3 Program Implementation . . . . . . . . . . . . . . . . . . 15 2.7.4 Training . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 3. Applicable Laws and Regulations . . . . . . . . . . . . . . . . . . 17 3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.2 Laws and Regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.3 Federal Laws and Regulations that Pertain to LowLevel Radioactive Waste . . . . . . . . . . . . . . . . . . . . . . . . . 18 3.3.1 Atomic Energy Act of 1954 and Related Laws . . 18 3.3.2 Radioactive Materials . . . . . . . . . . . . . . . . . . . . . 20 3.3.3 Low-Level Radioactive Waste . . . . . . . . . . . . . . . 20 3.4 Federal Laws and Regulations that Pertain to Hazardous, Mixed, and Multiple Hazard Waste . . . . . . 22 3.4.1 Hazardous Waste . . . . . . . . . . . . . . . . . . . . . . . . . 22 3.4.2 Low-Level Mixed Waste. . . . . . . . . . . . . . . . . . . . 23 3.4.3 Medical and Biological Waste . . . . . . . . . . . . . . . 24 3.5 Federal Laws and Regulations that Deal with the Minimization of Radioactive, Hazardous, Mixed, and Multiple Hazard Waste . . . . . . . . . . . . . . . . . . . . . . . . . . 26 3.5.1 Minimization of Low-Level Radioactive Waste . 26 3.5.2 Minimization of Hazardous Waste . . . . . . . . . . . 27 v

vi / CONTENTS 3.5.3 Minimization of Mixed and Multiple Hazard Waste . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 3.5.4 The Pollution Prevention Act of 1990 . . . . . . . . . 29 3.6 State Laws and Regulations that Deal with the Minimization of Low-Level Radioactive Waste and Low-Level Mixed Waste. . . . . . . . . . . . . . . . . . . . . . . . . . 31 4. Low-Level Radioactive and Mixed Waste Generation Trends . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 4.2 Low-Level Radioactive Waste Generation Trends . . . . . 33 4.3 Low-Level Mixed Waste Generation Trends . . . . . . . . . 37 4.4 Low-Level Mixed Waste Generation in Laboratory Analysis Waste . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 5. General Guidance for Development and Implementation of an Effective Institutional Waste Minimization Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 5.2 General Guidance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 5.2.1 Management Support. . . . . . . . . . . . . . . . . . . . . . 42 5.2.2 Waste Minimization Goals . . . . . . . . . . . . . . . . . . 43 5.2.3 Waste Minimization Options . . . . . . . . . . . . . . . . 43 5.2.4 Employee Awareness and Incentives . . . . . . . . . 44 5.2.5 Training. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 5.2.6 Quality Control . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 5.2.7 Trend Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 5.2.8 Waste Characterization . . . . . . . . . . . . . . . . . . . . 47 5.2.9 Waste Accounting . . . . . . . . . . . . . . . . . . . . . . . . . 48 5.2.10 Waste Cost Accounting and Allocation . . . . . . . . 50 5.2.11 Identification of Waste Minimization Opportunities . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 5.3 Information Exchange and Technology Transfer . . . . . . 52 5.4 Program Review and Update. . . . . . . . . . . . . . . . . . . . . . 55 6. Guidance for Selection of Waste Minimization Methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 6.2 General Guidance for the Selection of Minimization Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 6.2.1 Pollution Prevention Hierarchy . . . . . . . . . . . . . . 61 6.2.2 Occupational Health and Safety . . . . . . . . . . . . . 61

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Regulatory Considerations . . . . . . . . . . . . . . . . . 62 Analysis and Characterization Costs . . . . . . . . . 63 Sequence of Minimization Steps . . . . . . . . . . . . . 63 On-Site versus Off-Site Management . . . . . . . . . 64 Cost Effectiveness . . . . . . . . . . . . . . . . . . . . . . . . 64 Final Disposal Method . . . . . . . . . . . . . . . . . . . . . 65 Additional Considerations for Low-Level Mixed Waste and Low-Level Multihazardous Waste . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 6.2.10 Special Considerations for Low-Level Multihazardous Waste that Contains Infectious Agents or is Regulated as Medical Waste . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 6.2.3 6.2.4 6.2.5 6.2.6 6.2.7 6.2.8 6.2.9

7. Waste Minimization Methods and Examples . . . . . . . . . 71 7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 7.2 Source Reduction Methods . . . . . . . . . . . . . . . . . . . . . . . 71 7.2.1 Product Changes . . . . . . . . . . . . . . . . . . . . . . . . . 72 7.2.2 Source Control . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 7.2.2.1 Acquisition Management. . . . . . . . . . . . 72 7.2.2.1.1 Procurement Controls . . . . . 73 7.2.2.1.2 Supplier Agreements . . . . . . 74 7.2.2.2 Input Material Changes . . . . . . . . . . . . 74 7.2.2.2.1 Material Purification . . . . . . 74 7.2.2.2.2 Material Substitution: Radioactive Materials . . . . . 75 7.2.2.2.3 Material Substitution: Radioactive Microspheres . . 79 7.2.2.2.4 Material Substitution: Short-Lived Radionuclides . 80 7.2.2.2.5 Material Substitution: Hazardous Chemicals . . . . . 81 7.2.2.2.6 Material Substitution: Biohazardous Materials . . . 86 7.2.2.3 Technology Changes . . . . . . . . . . . . . . . 87 7.2.2.3.1 Process Changes: Equipment, Piping or Layout Changes . . . . . . . . . . 87 7.2.2.3.2 Process Changes: Additional Automation. . . . . . . . . . . . . . 89

viii / CONTENTS Process Changes: Changes in Operational Settings; Microscale Techniques . . . . . 90 7.2.2.4 Good Operating Practices . . . . . . . . . . . 91 7.2.2.4.1 Procedural Measures . . . . . . 91 7.2.2.4.2 Loss Prevention . . . . . . . . . . 93 7.2.2.4.3 Waste Segregation . . . . . . . . 94 7.2.2.4.4 Waste Segregation: Chemical Compatibility . . . . . . . . . . . . 95 7.2.2.4.5 Waste Segregation: Radioactive/Nonradioactive Wastes . . . . . . . . . . . . . . . . . . 95 7.2.2.4.6 Waste Segregation: Long/ Short Half-Life Wastes. . . . . 95 7.2.2.4.7 Waste Segregation: Deregulated/Non-deregulated Wastes . . . . . . . . . . . . . . . . . . 96 7.2.2.4.8 Waste Segregation: Deregulated Liquid Scintillation Counting Wastes from Non-deregulated Wastes . . . . . . . . . . . . . . . . . . 96 7.2.2.4.9 Waste Segregation: Deregulated Animal Carcass Wastes from Excreta and Other Radioactive Biohazardous Wastes . . . . . . 97 7.2.2.4.10 Waste Segregation: Radioactive/Hazardous Wastes . . . . . . . . . . . . . . . . . . 97 7.2.2.4.11 Waste Segregation: Hazardous/Nonhazardous Wastes . . . . . . . . . . . . . . . . . . 98 7.2.2.4.12 Waste Segregation: Listed/Characteristic Hazardous Wastes . . . . . . . . 98 7.2.2.4.13 Waste Segregation: Biohazardous/ Nonbiohazardous Wastes . . . 99 7.2.2.3.3

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7.2.2.4.14 Waste Segregation: Resource Conservation and Recovery Act Regulated/Nonregulated Low-Level Mixed Waste. . . . 99 7.2.2.4.15 Waste Segregation: Treatability Groups . . . . . . 100 7.2.2.5 Material Handling Improvements . . . 102 7.2.2.5.1 Contamination Control . . . 102 7.2.2.5.2 Production Scheduling. . . . 104 7.3 Waste Management Methods . . . . . . . . . . . . . . . . . . . . 105 7.3.1 Recycling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 7.3.1.1 Use and Reuse—Returning Waste to Original Process Without Reprocessing. . . . . . . . . . . . . . . . . . . . . 107 7.3.1.2 Use and Reuse—Use of Waste as Raw Material Substitute for a Different Process Without Alteration or Separation . . . . . . . . . . . . . . . . . . . . . . 109 7.3.1.3 Reclamation—Return of Materials to Original Use After Regeneration . . 109 7.3.1.4 Reclamation—Processing to Recover Usable Components or Energy (Fuel Blending) . . . . . . . . . . . . . . . . . . . . . . . 110 7.3.2 Treatment for Storage or Disposal . . . . . . . . . . 112 7.3.2.1 Hazard Reduction Methods . . . . . . . . . 112 7.3.2.1.1 Radiotoxicity Reduction: Decay of Short-Lived Radionuclides . . . . . . . . . . . 112 7.3.2.1.2 Radiological Hazard Reduction: Decontamination . . . . . . . . 114 7.3.2.1.3 Chemical Hazard Reduction . . . . . . . . . . . . . . 115 7.3.2.1.4 Chemical Hazard Reduction: Bioremediation 117 7.3.2.1.5 Chemical Hazard Reduction: Granular Activated Carbon Filtration . . . . . . . . . . . . . . 118

x / CONTENTS Chemical Hazard Reduction: Oxidation Methods . . . . . . . . . . . . . . . 119 7.3.2.1.7 Chemical Hazard Reduction: Ultraviolet Peroxidation . . . . . . . . . . . . 120 7.3.2.1.8 Chemical Hazard Reduction: Steam Reforming . . . . . . . . . . . . . . 121 7.3.2.1.9 Biohazards and Medical Waste Characteristics . . . . 121 7.3.2.1.10 Biohazard Reduction: Inactivation of Pathogens . 122 7.3.2.1.11 Biohazard Reduction: Chemical Disinfection . . . . 123 7.3.2.1.12 Biohazard Reduction: Steam Autoclave Sterilization . . . . . . . . . . . . 124 7.3.2.1.13 Biohazard Reduction: Preservation . . . . . . . . . . . . 124 7.3.2.2 Volume or Quantity Reduction Methods. . . . . . . . . . . . . . . . . . . . . . . . . 125 7.3.2.2.1 Minimization . . . . . . . . . . . 125 7.3.2.2.2 Compaction . . . . . . . . . . . . . 126 7.3.2.2.3 Concentration . . . . . . . . . . . 127 7.3.2.2.4 Decontamination of Surfaces Before Disposal . . 128 7.3.2.2.5 Other Volume Reduction Techniques for Biological Wastes . . . . . . . . . . . . . . . . . 128 7.3.2.2.6 Other Volume Reduction Techniques for Biological Wastes: Drying . . . . . . . . . . 129 7.3.2.2.7 Other Volume Reduction Techniques for Biological Wastes: Biological Reduction . . . . . . . . . . . . . . 129 7.3.2.1.6

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Other Volume Reduction Techniques for Biological Wastes: Grinding and Shredding . . . . . . . . . . . . . . 129 7.3.2.2.9 Other Volume Reduction Techniques for Biological Wastes: Alkaline Hydrolysis . . . . . . . . . . . . . 130 7.3.2.3 Thermal Treatment . . . . . . . . . . . . . . . 130 7.3.2.3.1 Incineration . . . . . . . . . . . . 130 7.3.2.3.2 Other Thermal Processes: Plasma Arc . . . . . . . . . . . . . 132 7.3.2.4 Mobility Reduction Methods . . . . . . . . 132 7.3.2.4.1 Amalgamation . . . . . . . . . . 133 7.3.2.4.2 Controlling Effects of Chelating Agents . . . . . . . . 133 7.3.2.4.3 Microencapsulation (Sealing) . . . . . . . . . . . . . . . 134 7.3.2.4.4 Stabilization . . . . . . . . . . . . 134 7.3.2.4.5 Shielding . . . . . . . . . . . . . . 135 7.3.2.4.6 Vitrification . . . . . . . . . . . . 135 7.3.2.2.8

8. Designing Facilities for Waste Minimization. . . . . . . . 137 8.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 8.2 Waste Minimization Objectives in Facility Design . . . 137 8.3 Approaches to Facility Development . . . . . . . . . . . . . . 138 8.3.1 Use of Life-Cycle Modeling . . . . . . . . . . . . . . . . 139 8.3.2 Systems Engineering . . . . . . . . . . . . . . . . . . . . . 140 8.3.3 General Design Considerations for Pollution Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 8.3.3.1 Facility Features that Accommodate Optimized Processes . . . . . . . . . . . . . . 140 8.3.3.2 Selection of Construction Materials . . 141 8.3.3.3 Isolated Sources of Potential Contamination . . . . . . . . . . . . . . . . . . . 141 8.3.3.4 Facilitated Eventual Decontamination . . . . . . . . . . . . . . . . . 141 8.4 Pollution Prevention Design Considerations for Laboratory and Small Institutional Generators . . . . . 142 8.4.1 Laboratory and Other Satellite Collection and Accumulation Areas . . . . . . . . . . . . . . . . . . . . . . 143

xii / CONTENTS 8.4.1.1 Consideration Should be Given to the Number, Type and Size of Collection and Accumulation Areas . . . . . . . . . . . 144 8.4.1.2 Minimizing the Potential for Contaminating Storage and Accumulation Areas . . . . . . . . . . . . . . . 145 8.4.1.3 Secondary Containment for Liquid Waste Container Storage . . . . . . . . . . . 145 8.4.1.4 Appropriate Identification for Waste Accumulation Areas . . . . . . . . . . . . . . . 146 8.4.1.5 Special Considerations for Liquid Scintillation Counting Areas . . . . . . . . 146 8.4.1.6 Additional Considerations for LowLevel Radioactive Waste Accumulation Areas . . . . . . . . . . . . . . . 146 8.4.1.7 Additional Considerations for LowLevel Mixed Waste Accumulation Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 8.4.2 Temporary Waste Staging Areas Outside Laboratories . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148 8.4.3 Central Marshaling and Processing Areas . . . . 149 8.4.4 Treatment, Storage and Disposal Facilities for Low-Level Mixed Waste . . . . . . . . . . . . . . . . 151 8.5 Minimization of Wastes from Facility Decommissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151 8.6 Technologies for Minimization of Wastes from Decommissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 9. Unresolved Issues that Adversely Impact Waste Minimization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162 9.1 General Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 162 9.2 Regulatory Barriers to Effective Management. . . . . . . 162 9.2.1 Factors Contributing to Regulatory Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 9.2.1.1 Public/Community Opposition. . . . . . . 163 9.2.1.2 Dual Regulatory System for LowLevel Mixed Waste . . . . . . . . . . . . . . . . 164 9.2.1.3 Coordination Between Regulatory Agencies . . . . . . . . . . . . . . . . . . . . . . . . 164 9.2.1.4 Differing Risk Management Philosophies . . . . . . . . . . . . . . . . . . . . . 164

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9.2.1.5 Inconsistent Waste Minimization Policy. . . . . . . . . . . . . . . . . . . . . . . . . . . 165 9.2.1.6 Lack of Consistent Risk Assessment Methods in Low-Level Mixed Waste Regulation . . . . . . . . . . . . . . . . . . . . . . 165 9.2.1.7 Concurrent Regulation by Federal and State Agencies. . . . . . . . . . . . . . . . 165 9.2.1.8 Lack of Consistent Medical Waste Regulations. . . . . . . . . . . . . . . . . . . . . . 165 9.2.2 Examples of Specific Areas Where EPA and/or NRC Regulatory Change is Needed Under the Atomic Energy Act . . . . . . . . . . . . . . 166 9.2.2.1 Unrestricted Release Limits for Radionuclides in Solid Waste . . . . . . . 166 9.2.2.2 Unrestricted Release Limits for Radionuclides in Materials to be Recycled . . . . . . . . . . . . . . . . . . . . . . . . 168 9.2.2.3 Expansion of Deregulated Rule to Include all Wastes Regardless of Generation Process . . . . . . . . . . . . . . . 168 9.2.2.4 Exemption of Very Low-Level Mixed Waste for Disposition at Hazardous Waste Treatment, Storage and Disposal Facilities . . . . . . . . . . . . . . . . 169 9.2.2.5 Solubility Rule Needs Clarification to Facilitate Disposal via Sanitary Sewer . . . . . . . . . . . . . . . . . . . . . . . . . . 169 9.2.3 Examples of Specific Areas Where EPA Regulatory Change is Needed Under the Resource Conservation and Recovery Act. . . . . 170 9.2.3.1 Need for Uniform Implementation of Regulations Among EPA Regions and States . . . . . . . . . . . . . . . . . . . . . . . . . . 170 9.2.3.2 EPA Regions and States Allowance for Decay-in-Storage Without Resource Conservation and Recovery Act Permit . . . . . . . . . . . . . . . . . . . . . . 171 9.2.3.3 Clarification of Authorization to Treat Low-Level Mixed Waste in Containers Without Permits. . . . . . . . . . . . . . . . . . 171

xiv / CONTENTS 9.2.3.4 Allow Centralized Collection and Treatment of Wastes Within the Same Institution . . . . . . . . . . . . . . . . . . . . . . . 172 9.2.3.5 Allow Return of Treatment Residues to the Generator . . . . . . . . . . . . . . . . . . 172 9.2.3.6 Modification of Approved Analytical Methods to Meet Waste Minimization Objectives . . . . . . . . . . . . . . . . . . . . . . . 173 9.3 Infrastructure Issues Unique to Small Institutional Generators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 9.4 Need for an Adequate and Reasonable Waste Recycling, Treatment and Disposal Infrastructure . . . 174 9.4.1 Availability of Commercial Low-Level Mixed Waste Management Facilities . . . . . . . . . . . . . . 174 9.4.2 Slow Development of Commercial Disposal Sites for Low-Level Radioactive Waste and Low-Level Mixed Waste . . . . . . . . . . . . . . . . . . . 175 9.4.3 Need to Clarify Waste Classification and Permitting Issues for New Sites . . . . . . . . . . . . 176 9.4.4 Disposal Costs as a Driver for Volume Reduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176 9.5 Technological Barriers . . . . . . . . . . . . . . . . . . . . . . . . . . 177 Appendix A. Examples of the Implementation of Effective Waste Minimization Programs. . . . . . . . . . . . . . . . . . . . . 178 A.1 Low-Level Radioactive Waste Broad Licensee Example—A Large University (Massachusetts Institute of Technology) . . . . . . . . . . . . . . . . . . . . . . . . 178 A.1.1 Dry Solid Waste . . . . . . . . . . . . . . . . . . . . . . . . . 179 A.1.2 Aqueous Liquids . . . . . . . . . . . . . . . . . . . . . . . . . 179 A.1.3 Organic Liquids . . . . . . . . . . . . . . . . . . . . . . . . . 180 A.1.4 Liquid Scintillation Wastes . . . . . . . . . . . . . . . . 180 A.1.5 Animal Carcasses/Bedding. . . . . . . . . . . . . . . . . 180 A.1.6 Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181 A.2 Low-Level Mixed Waste Example—National Institutes of Health . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181 A.3 References for Examples of the Effective Implementation of Waste Minimization Programs for Various Types of Generators . . . . . . . . . . . . . . . . . . 182 Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183

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Acronyms and Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . 190 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192 The NCRP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207 NCRP Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227

1. Summary Public concern and increased cost of the disposal of low-level radioactive waste (LLRW) have led to a need to address the minimization of these wastes particularly as they pertain to research laboratories and other small users of radioactive materials. The information in this Report will prove valuable not only to the generator of this waste but to those organizations responsible for licensing and regulation. Since risks associated with waste are related to the concentration of the hazardous material, the quantity and form of the waste, and the potential for dispersion in the environment, the generator’s first priority should be the partial or total elimination of the source of the waste stream. Furthermore, waste that cannot be eliminated should be recycled in an environmentally safe manner. Next, waste that cannot be eliminated or recycled should, when feasible, be treated to reduce its hazards and to reduce the volume of the wastes. The final step is that of selecting a disposal method consistent with protection of the public health and the environment which is in compliance with federal and state laws and regulations. An overview of applicable laws and regulations is essential in understanding the needs for a waste minimization program. The production and disposal of radioactive wastes are ultimately guided and controlled by federal laws beginning with the Atomic Energy Act of 1954 (AEA), as amended, and now include the following: • Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA) • Hazardous and Solid Waste Amendments Act of 1984 (HSWA) • Low-Level Radioactive Waste Policy Act of 1980 (LLRWPA) • Low-Level Radioactive Waste Policy Amendments Act of 1985 (LLRWPAA) • Nuclear Waste Policy Act of 1982 (NWPA) • Pollution Prevention Act of 1990 (PPA) • Resource Conservation and Recovery Act of 1976 (RCRA), as amended • Toxic Substances Control Act of 1976 (TSCA) 1

2 / 1. SUMMARY These laws and resulting regulations are discussed in detail in Section 2. Regulations derived from these laws are usually administered and enforced by the U.S. Environmental Protection Agency (EPA), U.S. Nuclear Regulatory Commission (NRC), U.S. Department of Energy (DOE), U.S. Department of Defense (DOD), U.S. Department of Transportation (DOT), and the Occupational Safety and Health Administration (OSHA). The authority for implementing and enforcing many of EPA regulations is delegated to the states. The decreasing trend in waste generation by nuclear power utilities has been driven by the increased cost of waste disposal and by increased emphasis on overall plant performance by industry groups such as the Institute for Nuclear Power Operations. For example, it appears that the volume of these wastes has decreased sharply while the total radioactivity has remained nearly constant indicating that, in general, costs of disposal of LLRW are volume based. This reduction in utility waste is not seen in the small generators of waste, which suggests that waste minimization may be effective in reducing costs for them. Cost reduction for small generators can be a significant saving in overall project budgets. For the small generator, two sources of waste streams deserve particular mention. First, is the waste associated with analytical procedures, which has become a new source of wastes and can be expected to increase substantially with new activities such as decommissioning and environmental restoration. Second, is the large volume of scintillation fluids generated in research, academic and medical facilities. Currently these wastes in part are disposed into sanitary sewers without further regard to the radioactive materials content if they meet the requirements of 10 CFR Part 20.2003 (NRC, 2002a). An effective waste minimization program is required for each facility generating waste. To be effective, it is essential that the program be supported at all levels of management. A single individual with direct access to senior facility management should have responsibility for organizing, planning and promotion of all waste minimization functions. Waste minimization and management should be an integral part of the project and institutional planning and budgeting process. Effective strategies need the attention of senior management. Within this program an important element is the establishment of definitive and realistic goals. Employee awareness, incentives and training are essential to ensure that each individual involved in the program is an active participant in minimizing waste.

1. SUMMARY

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An important management tool is trend analysis which can assist not only in delineating the progress in meeting goals but the data can focus attention on where additional resources may be needed. Detailed guidance is given in Section 4. Characterization of the individual sources of waste streams, which is required by regulations, can substantially aid in maximizing volume reduction and waste minimization. This characterization should include the chemical and radiological composition of the waste, information on input material, material usage, the generation process, applicable regulatory standards, minimization methods, and disposal costs. Information exchange and technology transfer is of great importance in bringing innovative approaches to the waste minimization program. Section 5 contains a compendium of internet and other sources of information exchange. The selection of waste minimization methods should begin with consideration of source reduction or elimination. This should then be followed by consideration of recycling the waste. The next step is treatment of the waste prior to disposal. Optimization of treatment and disposal should be evaluated from regulatory compliance and cost perspectives. Although source reduction has been effective in manufacturing and other industrial applications, it is more difficult in the research and educational environment, particularly in medicine, where substitution of materials can be difficult. Section 5 provides general guidance on waste minimization. Section 6 provides discussion and examples on the importance of attention to equipment, layout and process changes for minimizing waste. For example, introduction of microscale techniques. Examples of good operating practices are also discussed and examples given in this Section. Waste segregation in all its facets is the predominate issue: radioactive/nonradioactive, long/short half-life, radioactive/hazardous, etc. Detailed discussion and examples for each technique of minimization are presented in Section 7 which deals primarily with biomedical applications of radioactive material. For example, it has been shown that savings obtained through bulk purchases can be lost in disposing of the unused material and short-lived radionuclides can often be substituted for long-lived radionuclides. The last method discussed in Section 7 is treatment for storage or disposal. In the discussion and in the examples a number of approaches are given. For radioactive waste, the objectives are to reduce the radiotoxicity, the volume, and mobility of the contained

4 / 1. SUMMARY radioactive materials. Further it is important to meet transportation, processor and disposal site requirements for waste that needs to be sent elsewhere for management. For mixed and multihazardous waste, an objective is to eliminate one or more of the hazardous properties to allow disposal as a single waste type. For multihazardous waste it is important to inactivate pathogens and other characteristics of regulated medical wastes. Section 8 provides specific guidance for the design of facilities with emphasis on the needs of the small user. Institutions handling radioactive material should incorporate pollution prevention and waste minimization considerations during the design of facilities. A primary issue during design is planning for a variety of waste handling areas such as satellite collection and assembly areas, temporary staging areas, central marshaling and processing areas, and treatment, storage and disposal areas. The objectives of good facility design will be met most effectively when the planners evaluate the complex interrelationships among the various processes, from construction to operation, decommissioning and demolition. There are a number of unresolved issues that adversely impact waste minimization. These are identified in Section 9. Of particular note are regulatory barriers to effective waste minimization. This is exemplified by the inconsistent approach to these issues by various federal and state regulations. For the small user, there is an absence of a well defined and focused infrastructure for waste.

2. Introduction 2.1 Purpose The beneficial use of radioactive material and ionizing radiation in education, research, medicine and industry results in the generation of LLRW. This waste requires environmentally safe methods of management and disposal. The cost of disposal has increased dramatically in recent years, and public concern regarding the safety of current and proposed disposal methods has also escalated. It is therefore timely and worthwhile to examine current LLRW generation and management practices to search for ways, both technical and institutional, to address this issue. The most effective way of addressing this waste management issue is to implement effective institutional practices that eliminate or significantly reduce the generation of these wastes. This is the subject of this Report. This Report identifies waste minimization principles, practices and techniques that generators can adopt and benefit from, and that regulators can use in developing regulations. Because of an identified need (NAS/NRC, 2001), the intended audience for this Report consists primarily of small institutional (biomedical, research and academic) generators and their regulators. It is believed that other larger generators, such as nuclear power utilities and DOE facilities, may also benefit from the general principles and the specific recommendations developed in this Report. An extensive list of references is appended to provide sources of additional information. 2.2 Background LLRW is defined under various federal laws as radioactive waste that is not high-level radioactive waste, transuranic waste, spent nuclear fuel, or certain byproduct materials defined in Section 11(e)(2) of AEA (1954). NRC is authorized under AEA to regulate all non-DOE byproduct, source, and special nuclear materials, and the waste generated by their use. NRC, in turn, can delegate 5

6 / 2. INTRODUCTION the authority to regulate most of this radioactive material and waste to states under the its Agreement State program. The responsibility to regulate non-DOE naturally occurring and accelerator-produced radioactive material (NARM) resides with the states. For purposes of this Report, waste is considered to be material that has served its useful purpose in its present form, and is intended to be discarded with or without further processing. For radioactive waste, the point at which material becomes waste has not been specifically defined in regulations. For hazardous chemical waste, the conditions under which material becomes a solid/hazardous waste is defined in 40 CFR Part 261 (EPA, 1980a). This lack of a precise definition of “radioactive waste” has not generally been a problem, since radioactive materials and wastes are regulated similarly under AEA (1954). Generators that are regulated under AEA are required by the regulatory agency, i.e., NRC or Agreement State, to keep exposures from radiation as low as reasonably achievable (ALARA) at all times and to provide for safe disposal of LLRW. There have been dramatic changes in the management and disposal of LLRW over the past couple of decades for several reasons. One is the rapidly escalating costs for disposal. Another is that public concern about the issue of nuclear waste disposal has grown considerably. And finally, LLRWPA (1980) and the Low-Level Radioactive Waste Policy Amendments Act (LLRWPAA, 1986) have given the responsibility of providing commercial LLRW disposal to the states, who are allowed to address this issue individually or by forming a Compact of states, which in turn has created the need for them to implement laws and regulations. Although LLRWPAA primarily addresses ultimate disposal of LLRW, some state and Compact laws and regulations more clearly recognize the value of improved waste minimization practices. The primary goal of any minimization program should be the elimination or reduction to the extent practicable of the hazardous components that are present in the waste. In addition to wastes that contain a low-level radioactive component, the scope of this Report also covers low-level mixed waste (LLMW) that contains hazardous or toxic chemical constituents or biohazardous materials. For purposes of this Report, such wastes are called low-level multihazardous waste (LLMHW). Regulated LLMW is a subset of LLMHW which contains radioactive material as defined by AEA (1954) and hazardous wastes that are regulated under HSWA (1984) of RCRA (1976) as amended and EPA regulations

2.3 COMMON TERMS USED IN THIS REPORT

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implementing RCRA. LLMW also includes waste which contains radioactive material defined by AEA and hazardous materials regulated under laws other than RCRA such as TSCA (1976). LLMHWs, on the other hand, can include a full range of other hazardous materials, such as medical wastes that are regulated under state or federal laws and regulations. For these wastes, the requirement for minimizing waste is clearly established. RCRA (1976), for example, includes mandates that require waste minimization. The U.S. Congress has shown strong intent to address the prevention of pollution regardless of the source. PPA (1990) states “pollution should be prevented at the source; pollution that cannot be prevented should be recycled in an environmentally safe manner, whenever feasible; and finally, disposal or other release into the environment should be employed only as a last resort and should be conducted in an environmentally safe manner.” There are three major reasons for adopting and implementing waste minimization as part of an overall management program. First, it usually makes disposal inherently safer because of the reduced toxicity and volume of the waste needing disposal. This, in turn, makes such disposal methods more publicly acceptable, particularly when responsible waste management programs designate disposal as the last resort after exhausting all other options that may be cost effective. Second, it reduces the overall cost of waste management and disposal. The savings arise not only from a reduction in the volume and toxicity of the waste, thereby leading to smaller direct costs for waste management and disposal, but also from a decrease in indirect costs, e.g., insurance, long-term liability, and potential for resource recovery. Finally, such a program is responsive to the national policy of pollution prevention expressed in RCRA (1976), PPA (1990), and other federal, state or local laws and regulations.

2.3 Common Terms Used in this Report Various terms are used in the literature and regulations regarding waste minimization practices and principles. This has resulted in some of the common terms being used differently to describe the various waste minimization activities. The most common waste minimization activities and terms as used in this Report are given below. More detailed definitions and references to regulatory definitions may be found in the Glossary.

8 / 2. INTRODUCTION • “Waste avoidance” is a general term that describes the partial or total avoidance of generating waste at the source. Waste avoidance can be enhanced through process modification, product substitution, improvements in input material purity, imposition of stringent house-keeping and management practices, segregation of waste as it is produced, increases in the efficiency of machinery, and process reuse. These techniques are generally exercised as a first step in a waste management program. When waste generation is totally prevented, it is called “source elimination”; when the volume or hazard exhibited by a waste is decreased, but not eliminated, it is called “source reduction.” As defined above, the terms source reduction or elimination exclude out-of-process recycling, dewatering, compaction, reclamation, and other out-of-process treatments. • “Disposal” means the intentional discharge, deposit, injection or placement of any hazardous waste into or on any land or water so that the waste or any constituent thereof may enter the environment by being emitted into the air or discharged into any waters, including groundwaters. Disposal activities are not generally considered to be waste minimization (EPA, 1986a). • “Recycling” is using, reusing or reclaiming materials/waste, including processes that regenerate a material or recover a usable product. In-process, closed-loop reuse, where the reclaimed material is fed back into the process, is considered here to be “source reduction,” rather than recycling. • “Pollution prevention” is often used synonymously with “waste avoidance.” As commonly used in environmental regulations, “pollution prevention” means “source reduction,” as defined below, and other practices that reduce or eliminate the creation of pollutants through increased efficiency in the use of raw materials, energy, water, or other resources; or protection of natural resources by conservation. • “Source reduction” means any practice that reduces the amount of radioactive material, hazardous substance, pollutant, or contaminant entering any waste stream or otherwise released into the environment (including fugitive emissions) prior to recycling, treatment or disposal; and reduces the hazards to public health and the environment associated with the release of such substances, pollutants or contaminants. The term “source reduction” does not include

2.4 HIERARCHY OF WASTE MINIMIZATION STEPS

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any practice which alters the physical, chemical, or biological characteristics; or the volume of a hazardous substance, pollutant or contaminant through a process or activity which itself is not integral to and necessary for the production of a product or the providing of a service. In some classification systems, however, recycling activities are sometimes considered source reduction. • “Treatment” is defined as any method, technique or process designed to change the physical, chemical, biological character or composition or renders it in a form that is acceptable for disposal (e.g., storage for decay). Some forms of treatment may be required by regulation for, or as a prerequisite, to disposal. It is noteworthy that some waste streams may actually increase in volume after treatment, although they would be environmentally safer for disposal due to an improved waste form. • “Waste management” used here includes all activities such as handling, treatment and storage applied to control the characteristics and disposition of wastes that have been generated. In broader usage the term may also include source reduction activities. • “Waste minimization” refers to management activities intended to reduce, to the maximum extent feasible, waste that is generated or subsequently treated, stored or disposed. It includes any source reduction or recycling activity undertaken by a generator that results in either (1) the reduction of total volume or quantity of waste or (2) the reduction of toxicity of the waste, or both, so long as such reduction is consistent with the goal of minimizing present and future threats to human health and the environment.

2.4 Hierarchy of Waste Minimization Steps The risks associated with waste are determined by the concentration of its hazardous constituents, the quantity of waste, the waste form, the potential for dispersion in the environment, and how easily it can be isolated from the biosphere. Hazard reduction is a primary goal of waste minimization. Waste management practices such as treatment may result in a smaller quantity or a better waste form. This suggests that planning for waste minimization should normally consist of the following four levels of activity taken in sequence:

10 / 2. INTRODUCTION • The generator’s main processes or activities are evaluated for possible opportunities for partial or total elimination of waste streams. • Processes and materials are managed, recycled or reclaimed to reduce the hazard and/or volume of the anticipated disposal of wastes produced during operation. • The materials and wastes intended for disposal are treated to reduce hazards and/or volume, enhance the long-term stability of the waste form, and comply with the regulations and waste acceptance criteria of disposal facilities. • A disposal method is selected that is protective of public health and the environment and in accordance with federal and state laws and regulations. The partial or total elimination of waste streams is the first priority of this hierarchy because it diminishes or eliminates the hazard and, at the same time, reduces the need for further waste management. The second priority achieves similar results, but requires some handling, is generally less efficient, and results in some potential for the generation of pollutants. The third involves further hazard or volume reduction for wastes that must be disposed. Table 2.1 lists the steps of this hierarchical waste minimization scheme, with waste disposal shown as the last step. In summary, this Report recommends the following philosophy for waste minimization: • Waste generation should be avoided or reduced at the source whenever feasible. • Waste that cannot be prevented should be recycled in an environmentally safe manner, when possible. • Waste that cannot be prevented or recycled should be treated whenever feasible to render it less hazardous to individuals handling the waste or to the environment, and to optimize its volume. • Land disposal of waste should be employed as a last resort and must be conducted in an environmentally safe and legal manner. 2.5 Scope of this Report The primary target audience for this Report is small institutional LLRW generators such as biomedical facilities, laboratories,

2.6 ORGANIZATION OF THIS REPORT

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TABLE 2.1—Hierarchical waste minimization steps. Level 1 Source Reduction

Level 2 Recycling

Material substitution Waste reduction Process modification Management of material going into process Segregation

Reclamation reuse

Level 3 Treatment

Compaction Incineration Chemical treatment Encapsulation Solidification Storage for decay

Level 4 Disposal

Land disposal in a licensed and/or permitted facility or release as permitted under applicable regulations

and academic institutions regulated by NRC or Agreement States. Although not specifically targeted, other categories of generators may also find the general recommendations of this Report useful. The recommendations address not only activities during facility operation, but also the entire life cycle of the facility from initial design to final decontamination and decommissioning. This Report is applicable to materials covered by AEA (1954) and to discrete NARM. Because of its unique nature and the different required management techniques, diffused naturally occurring radioactive material (NORM) (generally defined as containing 226Ra concentrations less than 74 Bq g –1) is not covered. This Report also does not include minimization techniques for wastes from remediation of contaminated land. However, this Report considers not only LLRW, but also LLMHW.

2.6 Organization of this Report This Report is intended to serve both as a general reference and as a handbook on specific methods for minimization of all forms of LLRW. Section 3 provides the regulatory framework for waste minimization activities. Section 4 provides information on waste generation trends to justify the focus of this Report. General guidance for managers of waste minimization programs is presented in Section 5. Section 6 provides guidance on selection of waste minimization techniques, and examples of each waste minimization technique are presented in Section 7. Section 7 is extensively referenced so that readers may find additional information on these techniques. Section 8 provides design considerations for waste minimization facilities that address activities over the entire life

12 / 2. INTRODUCTION cycle, including decontamination and decommissioning activities. Finally, Section 9 discusses various institutional and regulatory impediments to effective waste minimization practices and makes recommendations for regulatory changes needed to enhance minimization. This Report concludes with Appendix A that contains examples of effective waste minimization programs that have been implemented by various types of generators, an extensive Glossary, and a compendium of references on radioactive waste minimization, arranged alphabetically by author. Recent advances in pollution prevention and waste minimization technologies have led to a rapidly growing number of publications in this area. Readers are urged to consult electronic bulletin boards or Internet sites operated by government agencies, professional societies, and vendors to obtain the most current information on topics of interest. Some specific suggestions are provided in Section 5.3.

2.7 A Guide for Implementing an Effective Waste Minimization Program Since the beneficial use of radioactive materials in many circumstances results in the production of LLRW, it is important from a health and safety standpoint to safely and efficiently manage this waste. One of the most effective ways of managing this LLRW is to ensure that it contains insignificant long-lived radionuclides. Waste in a form that requires off-site disposal or storage should be produced only when necessary to achieve a significant benefit. Because of the escalation in cost of LLRW treatment and disposal and the almost certain higher cost of future disposal, waste avoidance and recycling are often the most cost-effective management practices that can be implemented. In addition, it is widely recognized that effective waste minimization and pollution prevention programs are the foundation of acceptance by the public of the beneficial use of any hazardous materials. It is reasonable to assume that before land disposal of any type of hazardous waste begins to be acceptable to the public, it must be demonstrated that all possible waste minimization and treatment options have been considered. Other benefits from an effective waste minimization program include: • reducing worker and public exposure • improving process efficiency

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• reducing or eliminating the potential for accidents or release of toxic materials • reducing compliance and other life-cycle costs • minimizing the potential for future liabilities • enhancing the image and credibility of the organization The following discussion provides a suggested strategy for implementation of the recommended waste minimization program elements and practices that are included in this Report. 2.7.1

Waste Minimization Planning

Proper planning is a very important aspect of the implementation of an effective waste minimization program. Ideally, planning for waste minimization should be initiated before new facilities are constructed or new processes that may generate waste are initiated. Some of the principal issues that must be considered in this planning process are discussed in Section 5.2. In the discussion that follows, some of these principles, as well as other necessary elements, are presented in a generally sequential manner. This discussion is directed primarily toward a radiation safety officer at a small, institutional type generator, but much of it can be applied to all types of generators. One of the most critical elements needed for an effective waste minimization program is top-level management support. The adoption of a waste minimization philosophy should be an integral part of the organization’s policy. This implies acceptance of up-front costs as well as all of the other necessary elements of a successful program, such as quality assurance, training, incentives, and the holding of realistic expectations. Ideally, the policy for implementing a waste minimization program should be directed by management. Then the radiation safety officer’s role is one of providing assistance in planning and implementation. If, however, management is not providing the impetus for program implementation, then engendering top management support needs to be the first step of the planning process. Probably the best way to achieve full management support is to perform a detailed cost and liability analysis that clearly shows the long-term cost effectiveness of a good waste minimization program. Management support should include the following specific elements (EPA, 1993): • Emphasis on the need for continuing evaluation and improvement;

14 / 2. INTRODUCTION • Encouragement to each individual in the organization to identify opportunities for effective waste minimization at all levels and support functions; • Incentives and recognition for those employees that develop new ideas and methods and those who do a good job with implementation of the program (recognition and publicizing of successes); • Explicit (quantitative or qualitative) goals that are achievable within a reasonable time frame; • Management commitment to implement recommendations from assessments and to consider suggestions; and • Designation of a waste minimization coordinator or teams from all levels of the organization. Proper and effective communication up and down the management chain is extremely important for promoting and evaluating a waste minimization program. Promotional messages to the employees need to be simple and clear to be effective. In a large institutional setting, one approach to attracting the individual generator’s attention is to allocate waste management costs directly to the user. A thorough understanding of the applicable regulations and regulatory guidance is critical. This is particularly true for facilities that may generate LLMW. It is incumbent upon the regulators to provide clear, concise waste management guidance when appropriate. Section 3 provides an overview of this issue. Another critical element is the development of a thorough understanding of the need for proper handling of all radioactive, hazardous, and other toxic materials that are being used or generated by the facility. This includes detailed knowledge of all processes and procedures that use these toxic materials. With this understanding and knowledge in place, one can begin to develop materials flow and balance sheets. These can be used early on to evaluate whether the very simple waste avoidance techniques of materials substitution, better inventory control, or process changes can eliminate or allow recycling of hazardous materials. If possible, facility design and layout should be evaluated and changes made to minimize the spread of contamination, reduce flow distance of materials, and provide in advance for the facilitation of decontamination and eventual decommissioning. For new facilities, planning for waste minimization should begin during the design phase. The design and layout aspects should be evaluated and incorporated during the conceptual design of a facility. Issues

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that should be considered in initial facility design are discussed in Section 8. 2.7.2

Program Goals and Evaluation

The setting of program goals is an important responsibility of management. Program goals must be realistic, well defined and articulated, and be capable of being achieved within reasonable time frames. An effective waste minimization program must be flexible enough to be revised if goals are not being met. Periodic waste minimization evaluations should be performed. These evaluations must be based upon well-defined and understood criteria and procedures. Key parameters need to be identified and trending analysis should be performed. The evaluations should also consider overall program effectiveness and results. Evaluations by independent auditors may be helpful to ensure that new ideas are being considered. Management should commit to the implementation of all reasonable recommendations from this evaluation process. 2.7.3

Program Implementation

Section 6 provides a description of an approach that could be used for the implementation of this recommended hierarchical waste minimization strategy. Table 6.1 shows the specific techniques and an outline for the examples that are discussed in Section 7. These sections have extensive references that will provide additional details, if needed. A waste accounting system should be established that keeps track of all waste generated and of all the hazardous constituents in the waste. This should provide the data necessary to assess progress toward goals and the need for program changes. In addition, the costs of waste management should be determined. These include direct costs, compliance and regulatory costs, occupational exposure and employee health costs, and savings in future potential liability. Only with this full accounting can the real benefits of waste minimization be known and reported. 2.7.4

Training

The availability of an effective training program is essential for a good waste minimization program. The training program must be focused at the user level and should stress practical

16 / 2. INTRODUCTION applications and procedures. The level of training should be commensurate with the job function and how it influences the generation of waste. Training programs should include: general awareness of the problem and why it is important to the workplace and safety, knowledge of all procedures and proven techniques for waste minimization, and advanced training of higher level employees for improved techniques and for innovative problem solving. There is also a need for improved technology and the rapid transfer of good practices within the organization and between generators. A clearinghouse for collection and dissemination of this information would facilitate this transfer.

3. Applicable Laws and Regulations

3.1 Introduction The passage of the Clean Air Act (CAA, 1963) and the Clean Water Act (CWA, 1972) were clear signals of the intention of the U.S. Congress to address the problem of the contamination of the air, water and land with hazardous pollutants. It is now apparent that such efforts must go beyond simply limiting discharges into specific environmental media. The ideal strategy would clearly be to avoid the production of potential pollutants. This involves the decisions of manufacturers and others to redesign products, find substitute materials, modify equipment and processes, and generally improve the management of production, all of which may entail some initial effort. But not only are such tactics environmentally sound, they also frequently prove to be cost-effective over the long term. The intent of this Section is to provide an overview of the legal and regulatory framework put in place to protect people and the environment from LLRW and LLMW, and an awareness of the aspects of that framework that support the minimization of those wastes. An annotated list of regulations applicable to the management of commercial LLRW has been published (DOE, 1992a) if more detailed information is needed.

3.2 Laws and Regulations The production, use and disposal of radioactive and other hazardous materials is ultimately guided and controlled by federal laws as discussed in Section 2.2, such as AEA (1954), RCRA (1976), LLRWPA (1980), and LLRWPAA (1986). These statutes are general in nature, in that they do not contain specific requirements for implementing the objectives of the statues (e.g., requirements directed at protection of human health and the environment) but 17

18 / 3. APPLICABLE LAWS AND REGULATIONS they authorize federal agencies to develop and enforce specific regulations for their implementation. NRC, for example, has considerable authority under AEA to write and enforce regulations on the use and handling of radioactive materials, including LLRW. To promulgate or amend a regulation, NRC will publish a Notice of Proposed Rulemaking in the Federal Register, followed by a Notice of Final Rulemaking (including responses to public comments), and then codify the final rule in the Federal Register. Once the regulation is in place, NRC’s inspectors have the authority (and responsibility) to visit licensees on a routine basis to ensure that its provisions are being properly adhered to, and to impose sanctions if they are not. For some activities, no federal agency has been given regulatory authority. Where Congress has been silent, authority to regulate can only be exercised by the states. In addition, Congress has enacted numerous environmental laws since the 1970s under which EPA has issued federal regulations. The authority implementing and enforcing some EPA regulations is delegated to the states.

3.3 Federal Laws and Regulations that Pertain to Low-Level Radioactive Waste 3.3.1

Atomic Energy Act of 1954 and Related Laws

The creation, safe management, and proper disposal of various kinds of LLRW are covered by a variety of laws and regulations. The Atomic Energy Act (AEA), first published in 1946 and amended in 1954 (AEA, 1954), was the first nuclear-related legislation enacted by Congress. It vested in the federal government complete control over the use of materials relating to nuclear energy; subsequent legislation allowed participation by private enterprise to encourage technological advances. The paramount objective of this act was to ensure our national defense and security, but it was also intended to direct the development, control, and safe use of atomic energy for peaceful purposes. AEA gave the U.S. Atomic Energy Commission and its regulatory successor, NRC, broad discretion with respect to developing standards for use and possession of the materials governed by the Act. (The authority of DOE to regulate its own facilities also derives from AEA.) It grants NRC authority to establish standards “as the Commission may deem necessary or desirable to…protect health or

3.3 LOW-LEVEL RADIOACTIVE WASTE

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to minimize danger to life or property.” NRC is responsible, in particular, for establishing regulations for the safe management of special nuclear material, source material, and byproduct material, and for licensing the use of these materials. NRC is authorized to delegate some of this responsibility to the states. By 1999, 31 states have entered into agreements with NRC that enable these “Agreement States” to license and control many activities, within their boundaries, that involve the use of these materials. Some radioactive materials, such as commercially produced NARM, are not regulated under any federal statute. Thus, these materials are currently regulated only by the states. Reorganization Plan No. 3 of 1970 (EPA, 1970) transferred to the Administrator of EPA the authority of the Federal Radiation Council to provide guidance to the President “…with respect to radiation matters, directly or indirectly affecting health…” This includes radiation from NARM. The Plan transferred to EPA the U.S. Atomic Energy Commission’s authority under AEA (1954) to establish protection standards for radioactivity in the environment that apply to radioactive materials regulated under AEA. (NRC is generally responsible for implementing environmental standards established by EPA under this authority.) Thus, EPA can develop protection standards to govern environmental releases accompanying the management and disposal of LLRW, in particular, and to provide environmental protection from other materials and processes that give rise to environmental radiation. NRC has issued regulations that govern disposal and release of LLRW into the environment. This exemplifies the potential awkwardness of different federal agencies (EPA and NRC) exercising authorities in the same area. In such situations, the added burdens of dual standards or regulations often are eliminated when EPA acknowledges that NRC licensing requirements provide a level of protection equivalent to EPA standards and licensees are no longer required to report to EPA. Other statutes that relate, directly or indirectly, to the minimization of radioactive waste, include: • • • •

RCRA (1976) HSWA (1984) TSCA (1976) LLRWPA (1980) which was replaced in 1985 by LLRWPAA (1986) • CERCLA (1980) as amended in 1986 by the Superfund Amendments and Reauthorization Act

20 / 3. APPLICABLE LAWS AND REGULATIONS • NWPA (1983) • PPA (1990) • a variety of waste management laws of the individual states Regulations derived from these laws are administered and enforced by EPA, NRC, DOE, DOD, DOT, OSHA, and other federal and state agencies. In nearly all situations, it is obvious which agency has authority and responsibility for writing and enforcing the applicable regulations for a law. Gaps and overlaps in the legal/ regulatory framework do exist, however, and must be resolved through administrative arrangements or in the courts. 3.3.2

Radioactive Materials

The legal and regulatory aspects of managing LLRW are complicated by the manner in which radionuclides, in general, have been categorized by applicable statutes. That is, the distinctions that have been created by law do not necessarily correspond to physical configurations of the waste, or environmental and safety considerations. The term “radioactive material” is defined, somewhat arbitrarily, in DOT regulations at 49 CFR Part 173.403 (DOT, 2001) as “…any material having a specific activity greater than 0.002 microcuries per gram.” Aside from that, it would appear that the term is not explicitly defined by AEA (1954), LLRWPA (1980), NWPA (1983), or CFR. Section 11 of AEA and 10 CFR Part 20.1003 (NRC, 2002a) only refer to source, special nuclear, and byproduct material. As a result, “radioactive material” has assumed somewhat different meanings, depending upon the context. In effect, most radioactive materials are encompassed in the definition of AEA materials except for NARM. (The naturally occurring decay progeny of uranium and thorium are not considered “byproduct” materials, except in uranium and thorium mill tailings, which are known as “11(e)2 wastes,” after the section of AEA where they are defined.) Thus most kinds of non-DOE NARM wastes (of which NORM wastes form a subcategory) are not covered by AEA or by the regulations of NRC. The same materials are, however, subject to state laws and regulations. 3.3.3

Low-Level Radioactive Waste

This Report addresses waste minimization issues as they pertain to LLRW and LLMW and discrete (i.e., small, localized quantities of) NORM.

3.3 LOW-LEVEL RADIOACTIVE WASTE

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The current statutory definitions of LLRW are contained in NWPA (1983), as amended, and LLRWPAA (1986). In NWPA, LLRW is defined as radioactive waste that: Clause (A) is not high-level waste, spent nuclear fuel, transuranic waste, or byproduct material as defined in Section 11(e)(2) of the Atomic Energy Act; and Clause (B) the NRC, consistent with existing law, classifies as low-level radioactive waste. LLRWPAA contains a similar definition, except transuranic waste is not excluded in Clause (A). The two definitions apply only to waste containing radioactive materials that are regulated under AEA (1954). The difference in the two statutory definitions in Clause (A) has little practical significance because the definition in LLRWPAA applies only to waste regulated by NRC or an Agreement State (i.e., it does not apply to DOE waste), there is little non-DOE transuranic waste requiring disposal at the present time, and current NRC regulations in 10 CFR Part 61 (NRC, 2001) require disposal of any such non-DOE waste in a geologic repository unless disposal elsewhere is approved by NRC on a case-by-case basis. NRC has not acted to implement the definition in Clause (B). Thus, LLRW currently is defined only by an exclusion as in Clause (A). The current definitions of high-level waste and spent fuel, as contained in NWPA, and the current definition of transuranic waste, as contained in the Waste Isolation Pilot Plant Land Withdrawal Act (WIPPLWA, 1992), are given in the Glossary. The byproduct material defined in Section 11(e)(2) of AEA essentially is uranium or thorium mill tailings. Note that since NARM is generally not AEA material, by the above definition, it cannot be considered a form of LLRW. Because minimizing this waste is important, the present Report will consider LLRW in its broader meaning, so as to incorporate NARM wastes. The current legal definition of transuranic waste is found in WIPPLWA. In 1983, NRC provided classifications for LLRW, based on radionuclide concentration and half-life [10 CFR Part 61.55 (NRC, 2001)]. These waste classes, A, B, C, and greater-than-Class-C, set upper limits on the concentrations of certain radionuclides, and thereby determine the waste acceptability for certain disposal methods. NRC regulations also allow licensees to dispose of limited amounts and concentrations of certain types of LLRW through release in gaseous and liquid effluents (10 CFR Part 20.1302),

22 / 3. APPLICABLE LAWS AND REGULATIONS through incineration (10 CFR Part 20.2004) and into sanitary sewers (10 CFR Part 20.2003) (NRC, 2002a). LLRWPA (1980) required NRC to “…establish standards and procedures…to exempt specific radioactive waste streams from regulation by the [NRC] due to the presence of radionuclides in such waste streams in sufficiently low concentrations or quantities as to be below regulatory concern.” NRC defined a level of radionuclide content in waste material that would be below regulatory concern (i.e., that would be sufficiently nonhazardous as to not warrant licensing or other NRC regulation) in a policy statement published in the Federal Register at 55 FR 27522 (NRC, 1990). This met with considerable public opposition, and the policy statement was withdrawn 3 y later [58 FR 50635 (NRC, 1993)] as a result of Congressional direction, which was undoubtedly stimulated to some degree by public opposition.

3.4 Federal Laws and Regulations that Pertain to Hazardous, Mixed, and Multiple Hazard Waste 3.4.1

Hazardous Waste

The Resource Conservation and Recovery Act (RCRA, 1976), an amendment to the Solid Waste Disposal Act (SWDA, 1965), was enacted in 1976. In 1989, RCRA was amended by HSWA (1984). These amendments expanded the scope of RCRA and increased the level of detail in many of its provisions. RCRA-based regulations can be found in 40 CFR Parts 260 through 280 (EPA, 1986a; 2001a). EPA and/or authorized states have the authority and responsibility for their implementation. Subtitle C of RCRA (1976) created a comprehensive federal program for the systematic, “cradle-to-grave” control of hazardous waste, covering the generation, transportation, treatment, storage and disposal of such wastes, and focusing on active and future facilities [as opposed to CERCLA (1980), which primarily addresses abandoned contaminated sites, including inactive or closed hazardous or radioactive waste disposal sites that were not properly permitted under current environmental laws]. Under Subtitle C, anyone generating more than threshold quantities of hazardous waste is required to notify EPA of the fact. Hazardous waste generators and transporters must employ management practices and procedures that comply with regulations established by EPA

3.4 HAZARDOUS, MIXED, AND MULTIPLE HAZARD WASTE

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and DOT, including those designed to ensure the effective operation of the manifest system that is used to track wastes from their point of generation, along their transportation routes, to the place of final treatment, storage or disposal. Owners and operators of a treatment, storage or disposal (TSD) facility must be in possession of a RCRA permit to actively manage RCRA hazardous wastes, and are thus subject to far more exacting and complex requirements than are those entities that only generate or transport hazardous wastes. The definition of “solid waste,” of which hazardous waste comprises a subcategory, covers “…sludge…, and other discarded material, including solid, liquid, semisolid, or contained gaseous material…” 40 CFR Part 261 (EPA, 1980a) defines a solid waste as “hazardous” if it exhibits characteristics of ignitability, corrosivity, reactivity or toxicity, or if it appears on a list of certain waste types, discarded commercial chemical products, or certain nonspecific sources. In a notable exclusion, byproduct, source and special nuclear material are specifically excepted from the definition of solid waste and hazardous waste under 40 CFR Part 261.4(a)(4) (EPA, 1980a). While NORM are not explicitly excluded from coverage, EPA’s Office of Solid Waste has not defined radioactivity as a characteristic of hazard under RCRA, and has not addressed NORM wastes through RCRA (1976). RCRA acknowledges the desire of most states to regulate their own hazardous wastes, and the federal government has even provided financial incentives for states to do so. EPA has authorized most states, Washington, DC, and the territory of Guam to implement the “base” RCRA hazardous waste program, which corresponds to the federal program prior to the enactment of HSWA in 1984. Individual states can receive approval from EPA to implement the more than 140 RCRA (1976) regulations that have been issued since then, if they incorporate the corresponding provisions into their state regulations. In general, once a state has received base-program authorization, it is generally required, by 40 CFR Part 271.21(e) (EPA, 2002), to adopt changes that are less stringent than the federal regulations. A few states are somewhat behind in this process, in particular with regard to the regulation of LLMW. 3.4.2

Low-Level Mixed Waste

In 1986, EPA noted that there existed confusion as to whether radioactive LLMW was covered by both AEA (1954) and RCRA (1976) or, since RCRA excluded AEA materials, by AEA alone:

24 / 3. APPLICABLE LAWS AND REGULATIONS While source, special nuclear, and by-product material are clearly exempt from RCRA, the extent of the statute's applicability to wastes containing both hazardous waste and source, special nuclear, or by-product material has been less evident…Given the lack of clarity on this issue, EPA did not previously require, as a condition of State authorization, that the State have regulatory authority over the hazardous components of radioactive mixed wastes… [51 FR 24504 (EPA, 1986b)]. The confusion was dispelled, and a change in policy announced, as this Federal Register notice continued: Today, we are hereby publishing notice that…radioactive mixed wastes are to be part of authorized State programs. The situation was further clarified by the Federal Facilities Compliance Act (FFCA, 1992). Part of the this Act amends Section 1004 of RCRA (1976) by adding: The term “LLMW” means waste that contains both hazardous waste and source, special nuclear, or by-product material subject to the Atomic Energy Act of 1954. (Note here, too, that a mixture of RCRA hazardous waste and NARM would not formally be considered LLMW.) The hazardous waste component of LLMW is now clearly subject to EPA’s RCRA regulations at 40 CFR Part 261 et seq. (EPA, 1980a), while the radioactive component is generally regulated by NRC or DOE. Any approach to the management of LLMW must address both RCRA and NRC and DOE handling and disposal requirements, if the waste cannot be physically separated into its two components. A state can assume responsibility for regulating the hazardous component of LLMW if it is a RCRA base-program authorized state and, in addition, has obtained additional authorization from EPA to regulate LLMW.

3.4.3

Medical and Biological Waste

As with LLMW, the handling and disposal of radioactively contaminated medical or biological wastes is governed not only by regulations that cover the radioactive material component, but also by others that deal with the medical/biologic or hazardous component.

3.4 HAZARDOUS, MIXED, AND MULTIPLE HAZARD WASTE

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The management of medical/biological wastes in general (whether or not they are radioactively contaminated) has been addressed in a variety of ways. In 1989, largely as a rapid response to the concern of the public and news media about empty syringes and drug vials washing up on beaches, the Medical Waste Tracking Act (MWTA, 1988) was passed as an amendment to RCRA (1976), becoming Subtitle J. It defined seven classes of medical wastes to be regulated:

• cultures and stocks of infectious materials • human pathological waste • human blood and blood products • used sharps (i.e., syringes, glass vials, knife blades, and other items capable of cutting tissue, which should be deposited in “sharps” containers) • contaminated animal wastes • biological wastes from people and animals isolated because of infection with highly communicable diseases • unused sharps

MWTA initially applied only to 10 covered states, and expired 2 y after it was passed, but regulations promulgated under this Act remain in 40 CFR Part 259 (EPA, 1989). Perhaps the greatest continuing significance of MWTA is that a number of states have adopted similar rules, requiring careful tracking and management of the regulated materials. Other federal regulatory agencies have promulgated regulations on medical/biohazardous wastes. OSHA regulations in 29 CFR Part 1910.1030 (OSHA, 2001) are designed to protect employees against occupational exposure to diseases borne by blood or other body fluids. DOT’s rules, published in the Federal Register in 1991 [56 FR 66124 (DOT, 1991)], require that packages containing regulated medical waste be properly identified and be capable of withstanding impacts and hostile environmental conditions. Similar regulations have been prepared by the U.S. Postal Service. In addition, several nonregulatory agencies, health care facility accreditation organizations, and other professional groups have developed pertinent guidelines.

26 / 3. APPLICABLE LAWS AND REGULATIONS 3.5 Federal Laws and Regulations that Deal with the Minimization of Radioactive, Hazardous, Mixed, and Multiple Hazard Waste 3.5.1

Minimization of Low-Level Radioactive Waste

The federal government has long been aware of the value of efforts to minimize LLRW. Indeed, NRC published a policy statement in 1981 that called on all generators of LLRW to reduce the volume of waste for disposal, and to establish programs that incorporated good volume reduction practices. Still, the issue of the minimization of LLRW has not been addressed in detail in the relevant federal acts or regulations. As noted above, however, regulations based upon AEA (1954) are suggestive of ways to reduce the volumes and radioactive material content of wastes that must be sent to a licensed radioactive waste disposal facility. 10 CFR Part 20 (NRC, 2002a) describes amounts and physical forms of radioactive materials that can be discharged into the sewage system or released into the air or water. Likewise, scintillation fluids and animal carcasses containing less than a specified amount of tritium or 14C can be disposed of without regard to the fact that they are radioactive. 10 CFR Part 20.2005 and 10 CFR Part 61.56(a)(8) (NRC, 1981; 2001) include minimum disposal site acceptance requirements which state that LLRW must be treated to the maximum extent practicable to reduce the potential hazards from waste containing hazardous, biological, pathogenic, or infectious materials. And, of course, for radionuclides with relatively short physical half-lives, LLRW reduction through storage for decay are accepted by regulatory agencies, as in 10 CFR Part 35.92 (NRC, 2002b). LLRWPA (1980) contains references to minimization aspects of waste management. Section 102(6)(i) states that any LLRW delivered under emergency conditions for access from one Compact/state to another is required to be reduced in volume to the greatest extent practicable. Also, in Section 102(7), the Secretary of DOE is instructed to provide continuing technical assistance to the Compacts/states for volume reduction and management techniques to reduce LLRW generation. This assistance has been provided by the National Low-Level Waste Management Program. Although alluded to in several places such as these, it would appear that the minimization of commercial LLRW is not, at present, a high priority item on any federal regulatory agenda. This may be because generators have been effective in minimizing

3.5 MINIMIZATION OF WASTE

/ 27

or reducing their volume of LLRW due to increasing disposal costs; i.e., there is no need for an aggressive regulatory program or federal action. The minimization of hazardous chemical waste, on the other hand, has received considerable attention. 3.5.2

Minimization of Hazardous Waste

HSWA (1984) established a national policy for minimizing the generation of hazardous wastes. Section 1003(b) states: The Congress hereby declares it to be a national policy of the United States that wherever feasible, the generation of hazardous waste is to be reduced or eliminated as expeditiously as possible. Waste that is nevertheless generated should be treated, stored, or disposed of so as to minimize present and future threat to human health and the environment. Section 3002(b) of RCRA (1976), moreover, provides direction on how waste minimization is to be implemented. It requires certification by a generator that: (1) the generator of the hazardous waste has a program in place to reduce the volume or quantity and toxicity of such waste to the degree determined by the generator to be economically practicable; and (2) that the proposed method of treatment, storage, or disposal is that practicable method currently available to the generator which minimizes the present and future threat to human health and the environment. In addition, generators and TSD facilities are required to report biennially on their waste minimization efforts, and on the results of those efforts [40 CFR Part 262.41(a)(6) and (7), (h), and (i)]. This is all described in EPA (2001b). The guidance also states: EPA is committed to a national policy for hazardous waste management that places the highest priority on waste minimization…EPA believes waste minimization programs should incorporate, in a way that meets individual organizational needs, the following basic elements common to most good waste minimization programs: (1) top management support; (2) characterization of waste generation and waste management costs; (3) periodic waste minimization assessments; (4) appropriate

28 / 3. APPLICABLE LAWS AND REGULATIONS cost allocation; (5) encouragement of technology transfer, and (6) program implementation and evaluation. In support of this commitment, Executive Order 12856 (58 FR 41981)1 requires each federal agency to develop (among other things) written pollution prevention strategies that incorporate the national priority on pollution prevention into its facility management and acquisition procedures. Along with these broad federal mandates, EPA has proposed a Hazardous Waste Identification Rule for process waste. This regulation would establish a constituent-specific, risk-based “floor” or threshold concentration for solid wastes that are designated as hazardous because they are RCRA-listed, or have been mixed with, derived from, or contain listed hazardous wastes (EPA, 1995a). Under this proposal, low-risk listed hazardous wastes that meet the “exit levels” would no longer be subject to RCRA’s hazardous waste management system as listed wastes. It is expected that this more logical approach, if adopted rule, will encourage pollution prevention and waste minimization. AEA materials (i.e., source, special and byproduct) are specifically excluded from the definitions of solid waste and hazardous waste under RCRA, and from the definition of a toxic substance under TSCA (1976). Thus, RCRA can serve as an example, since it does provide legal requirements for LLMW minimization programs, but it only applies to the hazardous component of LLMW. RCRA waste minimization programs and procedures can be readily adopted voluntarily for application to LLRW. 3.5.3

Minimization of Mixed and Multiple Hazard Waste

Non-DOE LLMW comes under the simultaneous jurisdiction of AEA (1954), LLRWPAA (1986), and RCRA (1976) Subtitle C. RCRA requires that the generators have a waste minimization plan and implement it. RCRA also mandates that before hazardous wastes are disposed of in the ground, they must be treated to reduce their toxicity [Land Disposal Restrictions (LDR)]. As noted above, a state with proper authorization from EPA can administer its own LLMW program in lieu of EPA’s. Since such states must have regulations 1

Executive Order 12856 of August 3, 1993 (58 FR 41981) “Federal compliance with right-to-know laws and pollution prevention requirements.”

3.5 MINIMIZATION OF WASTE

/ 29

at least as stringent as RCRA requirements, in theory, they all should include provisions for minimization of LLMW and for LDR. One situation commonly encountered with LLMW is that while a standard method of minimizing LLRW is storage for decay, RCRA (1976) may impose limitations on the duration of time over which the hazardous component (hence also the radioactive part) may be stored. To assist LLMW generators around this dilemma, EPA and NRC have jointly published guidance on the storage of LLMW (NRC, 1995). The guidance points out areas of flexibility within EPA and NRC regulations that relate to the storage of LLMW, and generally takes the position that decay-in-storage may be considered a “…necessary and useful part of the best demonstrated available technology treatment process.” As such, “…the limited periods of approved decay-in-storage of LLMW do not violate the RCRA Section 3004(j) storage prohibition,” which otherwise disallows indefinite storage of hazardous waste in lieu of performing the required best demonstrated available technology treatment analysis. Multiple hazard waste is subject to the same waste minimization incentives as any other LLRW. It is covered by RCRA (1976), but not as a Subtitle C waste, so none of the hazardous waste minimization requirements apply at present. 3.5.4

The Pollution Prevention Act of 1990

The only federal statute that directly addresses the issue of waste minimization in general is PPA (1990). This Act was introduced as part of the 1990 Budget Reconciliation bill, and faced little opposition since it was regarded as an “innocuous requirement of data collection and exchange, requiring industry to do some additional bookkeeping, but imposing no obligations on anyone to change modes of production or modes of pollution control.”2 PPA (1990) states that it is the policy of the United States that: …pollution should be prevented or reduced at the source whenever feasible; pollution that cannot be prevented should be recycled in an environmentally safe manner, whenever feasible; pollution that cannot be prevented or recycled should be treated in an environmentally safe manner, whenever feasible; and disposal or other release 2

Congressional Record, S.17S23 to S.17S2S (daily edition October 27, 1990).

30 / 3. APPLICABLE LAWS AND REGULATIONS into the environment should be employed only as a last resort and should be conducted in an environmentally safe manner. This is also consistent with the waste management hierarchy included in RCRA (1976). PPA and energy conservation programs are considered by many to make good sense, in general, and to be socially beneficial, but it is not immediately obvious how to make it work in practice. Still, PPA does direct the Administrator of EPA to develop and implement a strategy to promote source reduction. To this end, the Administrator is required to, among other things: • establish standard methods of measuring source reduction • ensure that EPA considers the effects of its own regulations and other programs on source reduction • facilitate the adoption of source reduction techniques by businesses • recommend to Congress what should be done to eliminate barriers to source reduction • identify opportunities to use federal procurement to encourage source reduction • establish an Office of Pollution Prevention within EPA to carry out the purposes of PPA (1990) It has not been demonstrated how much real impact these requirements will have on the operations of facilities that make use of radioactive materials. “Source reduction” is defined by PPA (1990) to mean any practice which either reduces the amount of any hazardous substance, pollutant or contaminant entering any waste stream or otherwise released into the environment (including fugitive emissions) prior to recycling, treatment or disposal; or reduces the hazards to public health and the environment associated with the release of such substances, pollutants or contaminants. The term includes equipment or technology modifications, process or procedure modifications, reformulation or redesign of products, substitution of raw materials, and improvements in housekeeping, maintenance, training or inventory control. Not included within “source reduction,” as defined in PPA (1990), is any practice which alters the physical, chemical or biological characteristics or the volume of a hazardous substance, pollutant or contaminant through a process or activity which itself is not

3.6 STATE LAWS AND REGULATIONS

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integral to and necessary for the production of a product or the providing of a service, e.g., simple incineration. A premium is thus placed on ordinary improvements in housekeeping and maintenance. While it is not one of the more action-forcing environmental statutes, PPA does provide the basis for promulgating source reduction standards and goals. 3.6 State Laws and Regulations that Deal with the Minimization of Low-Level Radioactive Waste and Low-Level Mixed Waste In some states, LLRW and LLMW disposal laws and regulations have already incorporated waste minimization as an explicit condition for waste disposal. There are several obvious reasons for this additional requirement. Less waste volume and toxicity assures safer disposal. Also, the requirement for waste minimization may encourage public acceptance of land disposal by supporting the view that only the components of the waste that cannot be eliminated will need land disposal. Some states have been designated as host states to develop, construct and operate a LLRW disposal facility for their respective Compacts. As part of this process, they are, under agreement with NRC, developing their own legislation and regulations for management of the facilities, including waste minimization activities. For example, Pennsylvania's Low-Level Radioactive Waste Disposal Act (PALLRWDA, 1988) requires the Pennsylvania Department of Environmental Protection to implement policies, including fee schedules and other incentives, that encourage reduction in the volumes and toxicity of LLRW produced within the Compact region. The Act also requires the development of regulations for the permitting of generators, brokers and carriers for access to the regional disposal facility, and requires that each generator have a plan for reduction of toxicity and volume of LLRW, with stated reduction goals. The laws of a number of other states require similar actions. Thus it would appear that some state regulatory programs have been more active than their federal counterparts in addressing waste management and minimization issues. It is to be anticipated that this general movement on the part of states toward LLRW and LLMW minimization regulatory activity will continue. It is clearly advantageous for managers of LLRW and LLMW to establish and maintain close and harmonious working relationships with the state officials who have authority over radioactive

32 / 3. APPLICABLE LAWS AND REGULATIONS and other waste management activities. This helps ensure that the managers are kept abreast of all relevant and applicable (and possibly changing) regulations; and that when questions of interpretation do arise, they are resolved promptly and fairly.

4. Low-Level Radioactive and Mixed Waste Generation Trends 4.1 Introduction Over the past couple of decades, commercial LLRW disposal costs have sharply increased due to the increasing surcharges as well as increasing operating costs at disposal sites. Because most fee systems at LLRW disposal sites have been volume based, the volume of LLRW has decreased dramatically. A cursory examination of LLRW disposal trends, prior to 1993 suggest that the volume decrease is due to a concentrated effort to improve LLRW management by the nation’s larger generators, where the economical benefit is magnified and substantial, while the smaller generators have been slower to improve management practices. 4.2 Low-Level Radioactive Waste Generation Trends There is a total of more than 21,000 NRC and Agreement State licenses currently active (NRC, 1994a). The distribution of these licenses by generator category is shown in Figure 4.1. Medical, industrial research and development, and academic generators comprise about 45 percent of all NRC and Agreement State licenses. Utility licenses are not shown (about 100 power reactors nationwide) and some government generators may be included in the medical category. The category labeled “Other” includes mostly source material, special nuclear material, and general or exempt distribution licensees. Using data collected by the DOE National LLRW Program (Fuchs, 1997), the volume of commercial LLRW disposed by the major categories of generators over the period 1985 to 1996 is compared in Figure 4.2. The activity in the commercial LLRW disposed over the same period is shown in Figure 4.3. The utility category includes only commercial nuclear power reactors. The academic 33

34 / 4. LLRMW GENERATION TRENDS Other 8%

Academic 1% Medical 34%

214 Academic 7,291 Medical Industrial Industrial (R&D, labor) 2,144 Industrial Industrial (other) 10,078 Other 1,715 Industrial (R&D, Total 21,443 labor) 10%

Industrial (other) 47%

Fig. 4.1. Breakdown of NRC and Agreement State licensees by generator category (NRC, 1994a). 80 Total Util.

Volume x 103 (m3)

70 60

Ind.

50 40 30 20 10 0 4.5 4.0

Volume x 103 (m3)

3.5 3.0 2.5

Gov. Acad. Med.

2.0 1.5 1.0 0.5

1996

1995

1994

1993

1992

1991

1990

1989

1988

1987

1986

1985

0

Year

Fig. 4.2. Volumes of various categories of commercially-generated LLRW disposed over the period 1985 to 1996 at commercial LLRW disposal sites (Fuchs, 1997).

4.2 LOW-LEVEL RADIOACTIVE WASTE GENERATION TRENDS

/ 35

Activity x 106 (GBq)

40 Total Util.

35 30 25 20 15 10 5 0

Activity x 106 (GBq)

6 Ind. Gov.

5 4 3 2 1

Activity x 106 (GBq)

0

0.09 0.08 0.07

Acad. Med.

0.06 0.05 0.04 0.03 0.02 0.01 1996

1995

1994

1993

1992

1991

1990

1989

1988

1987

1986

1985

0

Year

Fig. 4.3. Total activity of all categories of commercially-generated LLRW land disposed at commercial sites from 1985 to 1996 (Fuchs, 1997).

category includes university hospitals and university medical and nonmedical research facilities. Medical generators include hospitals and clinics, research facilities, and private medical offices. The industrial category encompasses private entities such as research and development companies, manufacturers, nondestructive testing, mining, fuel fabrication facilities, and radiopharmaceutical manufacturers. The government category includes local, state and federal agencies, with the exception of DOE facilities.

36 / 4. LLRMW GENERATION TRENDS Over this period, utility generators have been responsible for disposal of the majority of LLRW in the United States with 51.3 percent of the total volume and 83.4 percent of the total activity. Although most often used to describe the characteristics of LLRW, volume and radioactivity do not give a true representation of the potential risk to human health from of LLRW. For LLRW which has been land disposed, half-life and the potential for ingestion of the radionuclides are the critical factors which determine potential risk. Studies of actual LLRW waste streams suggest that the real long-term potential risk of most of the utility waste streams may be less than that for other categories of generators (Dornsife, 1995). This is due to the fact that most of the radionuclides in utility waste are short lived and have lower potential for ingestion. These studies also suggest that the long-term intrinsic risk of most of LLRW is less than the intrinsic risk of the naturally occurring radionuclides in an equal amount of soil. As shown in Figure 4.2, there was a reduction in the total volume of LLRW disposed from about 76,000 m3 in 1985 to about 20,000 m3 in 1993. The increase from 1990 to 1992 is most likely due to the scheduled closure of the Barnwell Facility in 1993, and significant decommissioning activities at industrial facilities. At the same time the volumes were decreasing between 1985 and 1993, the total radioactivity in LLRW has remained fairly constant as shown in Figure 4.3. This may suggest that about the same amount of LLRW has been generated over this time period, with advanced volume reduction techniques being implemented due to increasing disposal costs, especially at utilities and large industrial facilities. Although the data show a continuing decrease in volume and radioactivity for all generator categories after 1993, this may not be an accurate reflection of LLRW actually generated during this period. Over this time period there was limited disposal capacity due to the temporary closure of Barnwell and a large increase in disposal surcharge costs for most of the generators. In addition, not all LLRW that was disposed was reported into the DOE database. DOE data for 1998 (not shown in Figure 4.2) show an increase in total volume to 40,433 m3, which is the first full year that all disposal sites reported. For these reasons, any data beyond 1993 will not generally be included in the discussion that follows. Utilities reduced their volumes of LLRW disposed from about 43,000 m3 in 1985 to about 17,000 m3 in 1992, while the radioactivity of utility-generated waste generally increased during this period. Because of the economies of scale, utilities have the

4.3 LOW-LEVEL MIXED WASTE GENERATION TRENDS

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capability of better cost savings for improved waste reduction and minimization practices. In addition, utility management incentives during this time period encouraged volume reduction. The trends for industrial and government generated LLRW were consistent in that volumes generally decreased from 1985 to 1990 but increased after 1990 due to the upcoming scheduled closure of the Barnwell Facility in 1993 and significant decommissioning activities at industrial facilities. The radioactivity in LLRW from these generators generally increased during this period. The smallest of the generator categories, medical and academic, together represent less than five percent of all LLRW disposed at commercial LLRW sites during the period from 1985 to 1993. Because of the small amounts generated and less frequent shipments for disposal, trends are more difficult to identify. While the volume of LLRW disposed by these generators appears to remain about the same, the radioactivity in the waste may have increased. Although the available statistics are not adequate to provide definitive data on the issue, similar improvements in management practices by these smaller generators, which are the primary focus of this Report, may still be possible. These smaller generators also generally have a larger range of waste minimization options. Although there is evidence to support a conclusion that the largest academic and medical generators have significantly reduced waste disposal volumes over this time period, such a trend is not reflected in the data for these generator categories. Waste minimization has been a significant part of radiation safety programs at most large institutions (DOE, 1995a; Ring et al., 1993) where major reductions in waste shipments have occurred. For example, implementation of improved waste minimization and management methods at a large university complex reduced the amount of LLRW shipped for disposal by a factor of 60 in 1991 compared to 1980 (Ring et al., 1993). 4.3 Low-Level Mixed Waste Generation Trends Most LLRW is currently shipped to treatment or recycle facilities, which do not routinely report their data into a national database. There is only one commercial disposal facility for LLMW, and information on disposal at that site is not readily available. The only comprehensive database for LLMW generation is from a nationwide survey that was jointly conducted by EPA and NRC in 1990 (NRC, 1991). Unfortunately this survey has not subsequently been updated, so it is the only comprehensive source of information available. The objective of this survey was to compile a national

38 / 4. LLRMW GENERATION TRENDS profile on the volumes, characteristics and treatability of commercially generated LLMW by major facility category—academic, government, industry, medical, and nuclear utility. (These are the same categories that were used for the LLRW data.) The results of this national survey of LLMW are summarized in Table 4.1. This Table reports the estimated LLMW during 1990 that was generated, remains in storage, or cannot be treated using available technologies. These data have been statistically extrapolated by NCRP to reflect total national estimates based on the sample of the surveys sent out and returned. Also shown separately in Table 4.1 is the volume that was reported as liquid scintillation fluids (LSF), since this waste stream represented the bulk of LLMW reported and may require special management considerations. Based on the analysis of a more detailed breakdown of the number of respondents in each major generator category, the number of the facilities that represent small laboratory generators can be estimated. Table 4.2 shows this estimate as a percentage of all the generators that responded in a given category. This simplistically assumes that the volumes are proportional to this ratio. The analysis shows that small laboratory generators may generate 70 percent of the LLMW. It should be noted that about 82 percent of this LLMW was reported to be LSF. Much of this waste is exempted from NRC rules and can be disposed of without regard to its radioactive material content or can be sent to facilities that are licensed to recycle the material as supplemental fuel.

4.4 Low-Level Mixed Waste Generation in Laboratory Analysis Waste Waste minimization and pollution prevention objectives have received little consideration in the development of most of the analytical procedures that are currently approved for waste characterization. Laboratories that conducted radioactive waste analysis procedures are faced with an unprecedented increase in work load to meet generator needs for waste characterization and management. Generation of secondary wastes associated with these procedures may increase concomitantly unless more effective techniques for minimization of these wastes are developed, validated, approved and implemented. Much of the secondary wastes, particularly contaminated solvents from extraction procedures, are LLMW, which are difficult to manage and have few, if any, disposal outlets. Some commercial analytical laboratories refuse to accept

/ 39

4.4 LLMW GENERATION IN LABORATORY ANALYSIS WASTE

TABLE 4.1—Total commercial LLMW reported in 1990 by category of generator (NRC, 1991).a

LLMW as Generated (m3)

Category

All LLMW

LLMW with No Available Treatment (m3)

LLMW in Storage (m3)

LSF

All LLMW

LSF

All LLMW

LSF

Academic

821

762

154

121

10

3

Government

750

575

79

45

41

22

1,428

965

1,197

146

24

0

Medical

564

534

63

46

21

9

Nuclear utility

386

0

623

5

42

0

3,949

2,836

2,116

363

138

34

Industrial

Total a

This is an extrapolation to all generators from the reported data.

TABLE 4.2—Estimated LLMW generated by small institutional and laboratory type generators (NRC, 1991). Categorya

LLMW as Generated (m3) All LLMW

LSF

Academic (all)

821

762

Government (66% small labs)

495

380

Industrial (62% small labs)

885

598

Medical (all)

564

534

Nuclear utility (none)

0

0

Total small laboratory

2,765

2,274

a

The information in the parenthesis means percent of category generating laboratory waste.

40 / 4. LLRMW GENERATION TRENDS radioactive waste samples because they cannot dispose the secondary wastes generated by analyses. Analytical procedures have already become a significant source of new wastes at laboratories operated by government agencies and their contractors. This source has the potential to increase rapidly. DOE, alone, will require a large number of waste characterizations over a multiyear period to accomplish its goals in environmental restoration and waste management. Estimates vary, but two million analyses annually are expected to be required to support DOE’s environmental restoration and waste management programs (Green et al., 1994; 1996). The high costs of LLMW management and the limited treatment, storage and disposal options for LLMW prompted EPA staff to investigate LLMW generated from laboratory procedures and identify options for minimization and improved management of these wastes (EPA, 1996).

5. General Guidance for Development and Implementation of an Effective Institutional Waste Minimization Program 5.1 Introduction This Section provides general guidance on the management components of an effective minimization program. To implement an effective waste minimization program, generators have to understand, and appreciate that such efforts are very much in their own interest and should contribute to their long-term benefit. Since waste minimization principles must be considered in nearly every aspect of the facility life cycle, effective planning is an important element of this waste minimization philosophy. This Section provides recommended elements that should be included in an effective waste minimization program. Obviously, the scope of each element needs to reflect the size and complexity of the generator’s facility and organizational structure. EPA (1993), NAS/NRC (1995), and DOE (Pemberton, 1996) have issued numerous guidance documents to assist generators in developing waste minimization programs. These documents have been used to develop the recommendations of this Report and provide a framework to build programs and assure compliance with existing waste minimization policy and requirements.

5.2 General Guidance Generators have the responsibility for implementation of an effective waste minimization program. 41

42 / 5. GENERAL GUIDANCE FOR AN EFFECTIVE PROGRAM An institution-wide waste minimization plan should be developed by management which provides the basis for the specific waste minimization procedures, program management structure, and institution-wide goals. Detailed waste minimization plans and procedures should be developed by each generator within the organization which comply with this general plan and provide process and waste stream specific details. The institution-wide waste minimization plan should address the following issues. 5.2.1

Management Support

All levels of management should support a waste minimization program, and this support should be prominently and clearly stated in the waste minimization plan. This support should include making waste minimization part of organization policy, setting goals for reducing the volume and potency of waste types that are achievable within a reasonable time frame, committing to identifying opportunities for waste minimization, and identifying other management goals and incentives which promote the objectives of the waste minimization program. A principal role of facility management is establishing and fostering an effective waste minimization policy. The establishment of this policy is just as important during the planning process for design and operation of facilities as it is for post-operational situations where facilities are being decontaminated and decommissioned. All operations will eventually become post-operational activities, often with the same work force performing different roles, so the presence of an effective waste minimization program and culture during the entire life cycle of facilities is to be encouraged and supported. Creating and nurturing that culture involves management committed to thorough organization, planning, training, deployment (of personnel and technologies), continuous monitoring, and program corrections when necessary. From the perspectives of organization and planning, a single individual should be assigned responsibility for the institutionwide coordination and promotion of all waste minimization functions with direct access to facility management. That person's responsibilities should include the identification and assessment of existing and emerging waste minimization technologies. Working with affected workers, applicable technical alternatives must be identified, and all must be compared in terms of overall impacts on costs (including life-cycle costs) and schedule, sensitivity to outside influences, implications for final waste forms and volumes, and

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safety and environmental risks. Through these efforts, the facility manager can be made aware of the relative effectiveness of any waste management opportunity and its appropriateness for that facility. Detailed planning and analyses are important management tools, since opportunities for effective response are fewer once the facility and its processes are in place. However, management involvement must not be limited to high-level planning and budgeting. It should also include an appropriate emphasis on physical plant inspections, technical development programs, waste management trade-off studies, stakeholder coordination, regulatory agency involvement, and training program support. With the appropriate culture in place, the difficult technical problems can probably be dealt with directly and most effectively by the workers closest to each problem and thus most familiar with its key parameters, options for corrective action, and constraints. Good management may require delegating a significant portion of the decision-making process to those most technically involved and experienced, and providing them with the necessary training on policy and standards to ensure that management's expectations are realized. The process operator or the generator of the waste is often in the best position to ensure that all waste minimization opportunities are promptly identified and exploited. 5.2.2

Waste Minimization Goals

The plan should include definitive goals for waste minimization. Such goals must be specific, but not necessarily numerical, and must specify a reasonable time frame over which they are to be achieved. In order to assure acceptance and demonstrate progress, the goals need to be realistic. Goals should not be universal, but should be specific, determined by the needs of individual generators, and based on the number and complexity of their waste streams. Goals should also consider the resource base that rationally can be budgeted to this activity, minimizing worker and public radiation exposures, and the overall cost effectiveness. 5.2.3

Waste Minimization Options

There should be well-defined procedures in the plan for identifying current waste streams and their characterization in terms of volume, potency, and physical and chemical properties. The waste minimization plan should also describe the results of such

44 / 5. GENERAL GUIDANCE FOR AN EFFECTIVE PROGRAM identification as they become available. A program to track waste as it is generated and shipped should also be included. The plan should identify options for minimization, prioritize them, and implement the higher priority ones appropriately. The detailed requirements of the characterization, tracking, and options assessment are described in later sections. 5.2.4

Employee Awareness and Incentives

Personnel awareness and involvement are fundamental characteristics of any successful waste minimization program. Improving awareness becomes the vehicle to incorporate the minimization ethic into the work activities of all employees. Incentives should be established to encourage participation and innovation. Awareness programs can be designed to: • Recognize individual and team accomplishments and reward employees that identify cost-effective minimization opportunities; • Train employees on the waste-generating impacts that result from the way they conduct their work procedures and how wastes can be reduced and pollution prevented; general environmental protection activities and hazards at the site and minimization requirements, goals and accomplishments; and their responsibilities in minimization; • Integrate minimization awareness into the general orientation program for all employees; • Include minimization activities in the development of employee performance standards and evaluations; and • Include minimization goals and milestones in the evaluation of an operating contractor’s job performance and in fee incentives. 5.2.5

Training

Effective training of waste generators has been described as perhaps the most critical component of successful waste minimization programs (Holcomb et al., 1993;3 Rau, 1990). The success of 3 Holcomb, W.F., Austin, S.M., Rau, E.H., Zoon, R.A. and Walker, W.J. (1993). “Training as a strategy for management of biomedical mixed waste at the National Institutes of Health,” presented at the 1993 Summer National Meeting of The American Institute of Chemical Engineers, Seattle, Washington, August 15-18, 1993.

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any program depends on the awareness of and participation by generators. Individual generators of LLRW and LLMW, particularly in large institutions, are often unaware of the difficulty and extreme cost of waste disposal and mandates to minimize. Most generators are cooperative and will comply with waste minimization recommendations once they are aware of them. The training curriculum should ensure that all generators receive waste minimization training. An effective way to do this is to include waste minimization as a topic in related safety training courses that may be required for all users of radioactive materials. Training for generators of LLMW that contain EPA regulated hazardous waste constituents may be mandatory. Hazardous waste generators are required to successfully complete a program of classroom instruction or on-the-job training on generator requirements, and review the training annually [40 CFR Part 265.16 (EPA, 2001c)]. Waste minimization should be included in the course content. If training resources are limited, waste minimization training efforts should be focused on generators that produce the largest volumes of waste, waste streams that are difficult to manage or have the highest potential for reduction. Waste minimization training can be accomplished through a variety of mechanisms ranging from formal classroom training to distribution of educational flyers. For large institutions, the use of video tapes has proven to be a well accepted, cost- and resourceefficient method of reaching large numbers of employees (Holcomb et al., 1993).3 Other elements of an effective waste minimization training program include: • Clearly conveying the impacts of waste generation on the institution and the benefits of participating in the waste minimization program, e.g., reduced occupational exposure, environmental protection, cost avoidance, improved regulatory compliance and public acceptance. Case histories are helpful; • Review of general strategies for waste minimization, with emphasis on source reduction; • Focused training on waste minimization strategies for the specific types of wastes generated by processes under the control of the employees being trained; • Provisions to update training to cover process changes, new technologies, etc.; and

46 / 5. GENERAL GUIDANCE FOR AN EFFECTIVE PROGRAM • Methods to obtain additional technical information through clearinghouses and other means. It is important to provide specific training on waste management techniques to all levels of personnel in a research program in which radioactive materials are utilized. Research scientists, associates and technicians must all be fully versed in the preferred practice for the program to be effective. Intermediate and upper management must be aware of their responsibilities in authorizing the appropriate equipment and supplies to maintain the effectiveness of the program. Thorough initial training and routine retraining must be provided for all involved personnel to maintain a successful program. For many facilities, increased technical training in waste minimization practices and principles for middle management may be appropriate. Middle managers are in a position to facilitate and help upgrade many waste management and waste minimization processes. They can also encourage and help cultivate the waste minimization culture. This includes maintaining high standards of cleanliness and an innovative attitude among the workers, as well as fostering performance consistent with regulatory standards and management expectations. 5.2.6

Quality Control

There should be independent methods for ensuring that the program is meeting expectations. An essential technique for doing this is to track the waste and examining major deviations from expected or planned goals. Quality control techniques and audits may be used to assist management in meeting goals and objectives for waste minimization. A study of large corporations such as Xerox, 3M, and Dow Chemical, as well as the public sector, has shown that all successful waste management programs emphasize pollution prevention and include some aspects of total quality management (Kirk, 1993). 5.2.7

Trend Analysis

The waste minimization plan should include provisions for trend analysis of waste volumes and costs. Such analyses are invaluable tools for program planning and evaluation. Trend information can be used to determine progress in meeting established goals, evaluate the effectiveness of selected strategies, and

5.2 GENERAL GUIDANCE

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establish budgets for future operations. Most importantly, trend data should be used to adjust the focus or redirect program resources to waste streams or activities that produce the greatest potential cost savings and waste reductions.

5.2.8

Waste Characterization

Accurate and complete characterization of wastes is an important and often underemphasized component of minimization programs. Many academic, biomedical, governmental and industrial institutions do not characterize their LLRW sufficiently to achieve maximum volume reduction and waste minimization (Party and Gershey, 1989). Failure to develop a thorough and effective approach to waste characterization activities can have several adverse consequences: • Incomplete characterization can result in the application of improper waste management techniques and regulatory sanctions. • If characterization requirements are not clearly established, wastes may be overclassified with regard to radioactivity, concentrations of hazardous substances, or regulatory status to “be safe” or avoid burdensome analysis and characterization activities. This approach usually defeats minimization efforts, and may significantly increase waste management costs. • Over characterization such as conducting unnecessary analytical procedures can greatly increase costs and may increase waste generation (analytical procedures often generate LLMW). Generators of all types of waste must characterize wastes to the extent required by applicable regulations. In general, characterization data may be developed from generator knowledge, waste analyses, or a combination of these methods. Generators that treat, store or dispose of LLMW must obtain a detailed chemical and physical analysis of a representative sample of the wastes. Storage and treatment facilities for hazardous waste are required to have a detailed, written waste analysis plan. Effective waste characterization programs involve more than merely determining the chemical and radiological composition of the waste. Characterization data also should include information

48 / 5. GENERAL GUIDANCE FOR AN EFFECTIVE PROGRAM on the input materials, material usage, generation process, regulatory status, minimization and management methods, and unit disposal costs for the waste. Inclusion of generation process information for each waste stream is particularly important, especially when the wastes produced by a defined process are predictable both in form and composition. By using process knowledge as the primary basis for characterization, the need to perform analytical procedures may be eliminated, or the frequency of confirmatory analyses may be reduced. Reducing the number of analyses may result in substantial cost savings and less generation of secondary waste streams. Linkage of waste streams to their generation processes facilitates waste minimization opportunity assessments. A detailed methodology for modeling and simulation in laboratory process waste assessments has been developed (Lyttle et al., 1993). The methodology allows field personnel with process knowledge to develop baseline waste generation assessments and evaluate appropriate waste minimization technology. The sum of all characterization information about each discrete waste stream is usually referred to as a waste profile. Profile records may be maintained on electronic databases, as written documents, or both. The use of standardized formats ensures that all necessary data is collected and facilitates data retrieval and reporting. A section for recording minimization strategies should be included in the profile format. Profiles can then serve as valuable references for generators, providing a ready source of specific minimization guidance for each of the institution’s generation processes and waste streams. A LLRW waste profile system established for wastes generated by a university and hospital complex is described in Emery et al. (1992). A similar system has been developed and is used for tracking and profiling LLMW at the National Institutes of Health (NIH) (DOE, 1994a; Rau, 1997).

5.2.9

Waste Accounting

Waste accounting is the systematic collection of quantitative data on the amounts of wastes generated and disposed of by the institution. NRC and EPA regulations, permits and licenses usually require maintenance of extensive waste tracking, accounting data, and generation of summary reports. Waste accounting data are needed for effective planning and management of minimization activities. These data also provide the means to:

5.2 GENERAL GUIDANCE

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• Track quantities and characteristics of wastes that are being eliminated, recycled and reclaimed as a result of minimization efforts; • Provide feedback on the progress of minimization efforts; • Identify and prioritize waste generation processes for future minimization opportunity assessments and intervention; • Identify program resource requirements and report cost savings realized from minimization projects; and • Provide data required to meet federal and state reporting requirements.

In developing waste accounting systems, management must ensure that the system will provide the information needed to support the minimization program. In many cases, the information elements needed are in addition to those required to meet regulatory agency reporting requirements. Examples include data on procurement and input materials, and material usage; and collection of data by specific generation processes and time frames (before and after implementation of minimization strategies). Computerized systems are being increasingly used to track wastes from “cradle to grave.” These systems can be used to facilitate minimization activities and to aid in meeting minimization goals. For example, at the DOE Savannah River Site, each hazardous and radioactive waste generator who delivers waste to a TSD facility is required to implement a waste certification plan. This waste certification process ensures that the waste has been properly identified, characterized, segregated, packaged and shipped according to the receiving facility’s waste acceptance criteria. To comply with the rigid acceptance criteria, a computerized inventory for waste management has been established to track generation of wastes and their management through final disposal. The system includes a relational database with integrated bar code technology designed for waste tracking. During the development of the computerized system, waste minimization tools were incorporated into the design of the program. The inclusion of these tools has resulted in a 40 percent overall reduction in the volume of waste generated (Griffith and Holmes, 1996). A similar system has been implemented at Sandia National Laboratory (Kjeldgaard and Gillenwater, 1993).

50 / 5. GENERAL GUIDANCE FOR AN EFFECTIVE PROGRAM 5.2.10 Waste Cost Accounting and Allocation Facility operators should develop an accurate and current cost accounting system that accounts for the “true cost” of waste generation and management. The system should be capable of determining the short- and long-term cost arising from a variety of direct and indirect sources. “True costs” are associated with the generation and management of waste may include: • the cost of regulatory oversight and compliance • paperwork and reporting requirements • loss of production potential • costs of materials found in the waste stream • transportation, recycling, treatment, storage and disposal costs • exposure monitoring and health care • third party liabilities • possible future RCRA (1976) or CERCLA (1980) corrective action costs Where practical and feasible, institutions should appropriately allocate the true cost of waste management to the activities responsible for generating the waste (e.g., identifying specific operations that generate the waste, rather than charging the waste costs to “overhead”). Cost allocation can properly highlight the parts of the organization where the greatest opportunities for minimization exist. Without allocating cost, pollution prevention opportunities can be obscured by accounting practices that do not clearly identify the activities generating the wastes (U.S. Department of Health and Human Services Pollution Prevention Strategy cited in EPA, 1995b). Numerous sources of detailed guidance, models and examples of cost accounting and analysis systems for pollution prevention and hazardous waste minimization programs are available (EPA, 1988a; 1992a; 1994a; 1995b). The methodology used for hazardous wastes is applicable and readily adaptable to LLRW minimization programs. Activity-based costing methods used in connection with waste minimization activities at DOE facilities are described in detail by Hsu et al. (1995).

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5.2.11 Identification of Waste Minimization Opportunities Based on the institutional features, the generator should assess opportunities for pollution prevention and waste minimization. Such assessments, often referred to as pollution prevention opportunity assessments, are the heart of most successful waste minimization programs. These assessments are widely used at DOE facilities (Braye and Phillips, 1995; Griffen et al., 1995; Pemberton, 1997). They accomplish the goals of the waste minimization program by: • Highlighting how materials and technologies, individually and collectively, affect waste generation; • Systematically analyzing current process operations; • Identifying the processes that generate waste that must be targeted in the minimization program; • Developing a comprehensive set of options for minimization; and • Identifying the options that are the most attractive and deserving of further analysis and development, based on feasibility, cost-effectiveness, and risk avoidance (see Section 5.2.1). The procedure for conducting such assessments typically consists of the following three phases (adapted from EPA, 1988a): Phase One: Planning and Organization • elicit and confirm management’s commitment • set overall assessment program goals • organize assessment program task force • obtain management’s commitment to proceed Phase Two: Assessment Phase • collect process and facility data • select assessment targets and assign priorities • appoint people to assessment teams • review data and inspect waste generation areas • generate list of options • screen and select options for further study • generate assessment report on selected options Phase Three: Feasibility Analysis Phase • perform a technical evaluation • perform an economic evaluation

52 / 5. GENERAL GUIDANCE FOR AN EFFECTIVE PROGRAM • select options for implementation • review data and inspect site • prepare final report and recommended options Implementation of Pollution Prevention Opportunity Assessment Recommendations • justify projects and obtain funding • procure and install necessary equipment and supplies • implement recommendations • evaluate performance If performance is unsatisfactory, return to the assessment phase to reevaluate previous options or select new assessment targets. If performance is satisfactory, the project has been successfully implemented. Table 5.1, adapted from the EPA Waste Minimization Opportunity Assessment Manual (EPA, 1988a), lists examples of sources that may be useful in conducting assessments. Some large generators conduct assessments by assigning teams of specialists to evaluate waste minimization opportunities for specific waste generating operations and waste types, collect the data, and make estimates and recommendations (Griffen et al., 1995). Pilot assessments should be conducted to determine the priority of operations to be assessed and the estimated amount of effort involved (Pemberton, 1996). Work sheets for developing these assessments may be found in the EPA Waste Minimization Opportunity Assessment Manual (EPA, 1988a). These can be readily modified to meet specific institutional requirements. 5.3 Information Exchange and Technology Transfer Generators should seek out and exchange waste minimization information from other parts of the organization/facility, from other companies/facilities, trade associations/affiliates, professional consultants, and university or governmental technical programs. Assessments and related Executive Orders encourage information exchange, the development and testing of innovative waste minimization technologies, and the development of strong markets for such technologies. Industry, federal agencies, government laboratories, academia, and others have formed partnerships to assess and deploy innovative environmental technologies for domestic use

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TABLE 5.1—Examples of facility information useful for waste minimization assessments. Design Information • process flow diagrams • material and heat balances • operating manuals and process descriptions • equipment lists • equipment specifications and data sheets • piping and instrument systems • plan and elevation plans • equipment layouts and work flow diagrams Environmental Information • manifests and other waste shipping records • emission inventories and other environmental monitoring data • radiological contamination survey data • waste analyses • environmental audit reports • permits and licenses • permit and license applications Raw Material and Output Information • product composition and batch sheets • material application diagrams • material safety data sheets • product and raw material inventory record • operator data logs • operating procedures • production schedules Economic Information • waste treatment and disposal costs • product, utility, and raw material costs • operation and maintenance costs • departmental cost accounting reports Other Information • institutional environmental policy statements • standard procedures • organizational charts • pollution prevention information from technology transfer

and for markets abroad. A directory of publicly sponsored pollution prevention sources and exchanges across the United States has been developed (EPA, 1994b). Another useful source is the numerous sites on the Internet operated by EPA, DOE, and pollution prevention clearinghouses

54 / 5. GENERAL GUIDANCE FOR AN EFFECTIVE PROGRAM that can provide a wealth of waste minimization information. Contact with one site usually provides links to numerous other sites. Examples of Internet sites relating to waste minimization include: • Envirosense: An electronic bulletin board funded by EPA and the Strategic Environmental Research and Training Program, and operated by the Idaho National Engineering and Environmental Laboratory. It allows those implementing pollution prevention programs or developing research and development projects to benefit from experience, process and knowledge of their peers. • EPA LLMW Team Home Page: The EPA LLMW Team is a coordinated effort among EPA headquarters and regional offices dedicated to resolving the administrative, regulatory and technological hurdles that are facing government and private sector generators of LLMW. The home page provides information on the Team’s activities and links to other Internet sites and electronic copies of guidance documents. • EPA RCRA Waste Minimization and Pollution Prevention Page: This page provides links to numerous EPA pollution prevention resources. • DOE Center for Waste Management: The Center for Waste Management facilitates exchanges among the private sector, academia and government to help solve waste management problems. • DOE Hanford Pollution Prevention Home Page: This page describes efforts to minimize radioactive waste, hazardous waste, and LLMW at DOE’s Hanford Facility in Washington State. • National Library of Medicine: The Library at NIH maintains the world’s largest databases on medicine, toxicology and hazardous materials. Searches of biomedical databases such as PubMed and TOXNET using subject words such as “nonradioactive” and “waste” will yield hundreds of references on nonradioactive methods for assays and other procedures that generate LLRW. Although this Report provides general guidance on the variety of approaches that should be considered in a waste minimization effort, more specific sources of information are often available from organized groups directly associated with each prospective generator. Papers published in professional journals or presented at technical conferences and information notices released by

5.4 PROGRAM REVIEW AND UPDATE

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technical associations are all examples of documents in which each generator might seek specific guidance or solutions for their type of operation. This Report includes extensive references which provide this information. 5.4 Program Review and Update Program effectiveness reviews should be conducted at least annually and used to provide feedback and identify potential areas for improvement. Such reviews should include, at a minimum, trend information, assessment of success in meeting goals, information on effectiveness of selected techniques, and lessons learned. If these reviews indicate a trend significantly worse than expected or failure to meet the goals, the generator should promptly upgrade the plan. The upgraded plans should include all the elements of the original plan updated to reflect this new experience. It should also clearly identify the basis for the plan upgrade in terms of the inefficiencies and failures of the past program.

6. Guidance for Selection of Waste Minimization Methods 6.1 Introduction Various schemes have been developed by EPA and others to define, classify, and prioritize waste minimization methods. These schemes usually establish the following hierarchical steps: • Source reduction—partial or total elimination of wastes. • Recycling—beneficial use of generated wastes or waste components. • Treatment—conversion of hazardous constituents to less hazardous or nonhazardous materials, and reduction of the volume and mobility of wastes that must be stored or disposed. Source reduction, sometimes used synonymously with pollution prevention or waste avoidance, refers to actions taken to reduce or eliminate waste at the point of generation. EPA does not consider recycling methods to be source reduction. However, other classification schemes may include recycling as source reduction. Treatment is used primarily to reduce or eliminate the nonradiological toxicity of LLMW and LLMHW and reduce the volume of LLRW. Waste management, as used here, refers to recycling, treatment, storage, and all disposal operations and actions that are applied to generated wastes, but are not part of a process or service. Waste minimization, as used here, includes source reduction, recycling, and all waste management activities that reduce the volume of the waste, and reduce the present and future threat to human health and the environment prior to disposal. A more detailed listing of these hierarchical steps is given in Table 6.1. This Table also lists the important procedures (strategies) that apply to each of the three steps. Figure 6.1 summarizes this information. This information was adapted from EPA’s Waste Minimization Opportunity Assessment Manual (EPA, 1988a) to include methods applicable to LLRW and LLMHW. 56

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TABLE 6.1—Classification of waste minimization techniques by pollution prevention hierarchy. Source Reduction Methods Product changes Product substitution Product conservation Changes in product composition Source control Input material changes Material purification Material substitution Radioactive materials Nonradioactive materials Short-lived radionuclides Hazardous chemicals Biohazardous agents Disinfectants Disposables Technology changes Process changes Equipment, piping or layout changes Additional automation Changes in operational settings Microscale techniques Good operating practices Procedural measures Loss prevention Management practices Calibration and maintenance Waste stream segregation Radioactive/nonradioactive Short/long half-life Deregulated/non-deregulated Radioactive materials/hazardous substance RCRA regulated/nonregulated RCRA-listed/RCRA characteristic Radioactive/biohazardous or regulated as medical waste Material handling improvements Cleanable materials Liners and absorbents Dedicated areas for radioactive materials Avoidance of cross contamination Production scheduling

58 / 6. GUIDANCE FOR SELECTION OF WASTE MINIMIZATION METHODS TABLE 6.1—Classification of waste minimization techniques by pollution prevention hierarchy. (continued) Waste Management Methods Recycling Use and reuse Return to original process without reprocessing Use as raw material substitute for a different process without alteration or separation Reclamation Returned to original process after processing to regenerate material Processed to recover usable components or energy for another process Treatment for storage or disposal Hazard reduction methods Radiotoxicity reduction Decay Decontamination/removal of radioactive materials Chemical hazard reduction Destruction of hazardous chemicals Decontamination/removal of hazardous chemicals Biohazard reduction Inactivation of pathogens Preservation Processing to eliminate medical waste characteristics Volume or quantity reduction methods Compaction Concentration Decontamination of surfaces Other techniques for biological wastes Thermal treatment (hazard and volume reduction) Mobility reduction methods Amalgamation Macroencapsulation Microencapsulation Shielding Vitrification

6.2 GENERAL GUIDANCE

HIGHEST

/ 59

WASTE MINIMIZATION TECHNIQUES

RELATIVE ENVIRONMENTAL DESIRABILITY

SOURCE REDUCTION METHODS

PRODUCT CHANGES - Product substitution - Product conservation - Change in product composition

INPUT MATERIAL CHANGES - Material purification - Material substitution

SOURCE CONTROLS

TECHNOLOGY CHANGES - Process changes - Equipment, piping, or layout changes - Additional automation - Changes in operational settings

GOOD OPERATING PRACTICES - Procedural measures - Loss prevention - Management practices - Waste stream segregation - Material handling improvements - Process scheduling or sequencing

WASTE MANAGEMENT METHODS

RECYCLING

USE AND REUSE - Return to original process - Raw material substitute for another process

LOWEST

RECLAIMATION

TREATMENT FOR

- Processed for resource recovery - Processed as a by-product

DISPOSAL - Decay of radionuclides - Detoxification of chemicals - Inactivation of pathogens - Decontamination - Incineration - Volume reduction - Mobility reduction

Fig. 6.1. Classification of waste minimization techniques by pollution prevention hierarchy.

6.2 General Guidance for the Selection of Minimization Methods The success of any waste minimization activity depends on selecting appropriate minimization methods and technologies. Ideally, these methods and technologies should be established in waste stream specific minimization plans which are developed before initiating the processes that will generate wastes.

60 / 6. GUIDANCE FOR SELECTION OF WASTE MINIMIZATION METHODS Selection of minimization strategies for specific waste streams is a complex process requiring the involvement and consensus of diverse disciplines. Each option should be evaluated for its efficacy; potential to reduce wastes and associated hazards; and its short-term, long-term, and life-cycle costs. Selection of options without adequate analysis can result in potential health, safety and environmental hazards, conflicts with regulatory requirements, increased costs, and other adverse unintended consequences. Protocols for the assessment and selection of waste minimization options are now well established (EPA, 1988a). Most of these protocols were developed for manufacturing and other large scale processes carried out in industrial facilities. Although the applicability of industrial protocols is usually more influenced by the type of activities carried out by the institutional generator rather than the size of the institution, protocols developed for manufacturing are often difficult to apply to the waste streams produced by laboratories, research facilities, and educational institutions for the following reasons: • Small institutions typically generate numerous, discrete waste streams of small volume, and complex composition which are often nonrecurring. In many cases, it is not cost effective to conduct pollution prevention opportunity assessments and to develop source reduction strategies for specific generation processes due to the small volumes involved. • Other types of hazardous materials such as toxic chemicals or potentially infectious agents may also be present in LLRW that are not typically found in industrial wastes. The impact of strategies intended to minimize one component may affect other hazardous constituents and must be thoroughly evaluated before implementation. • Unlike manufacturing processes, the output of institutions with research or educational missions cannot be measured in terms of monetary or production units. Thus, it is often impossible to define life-cycle and related costs, and to evaluate pollution reduction efficiency in terms of discrete units. • In manufacturing or other industrial applications, alternative procedures and substitutions of chemicals or radionuclides necessary to achieve waste minimization objectives, can often be quickly implemented. Conversely, materials and procedures used in medicine cannot be changed without extensive testing to demonstrate safety, effectiveness and

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equivalency. Such testing may be very time consuming and expensive. Patient care and medical research mission objectives are paramount. • In particular, wastes from research applications are often unique, and no overall waste minimization screening methodology can be globally applied to the various waste generating processes. Each process should be evaluated in relationship to its research purpose and the available opportunities for waste reduction. • Researchers may be reluctant to modify established procedures and to adopt unproven techniques to minimize small amounts of waste. Validation of new techniques and substitute reagents may require repetition of past work and result in significant delays. Important factors that should be considered in evaluating various waste minimization strategies are discussed in the following sections. 6.2.1

Pollution Prevention Hierarchy

Absent consideration of any other factors, minimization methods should be selected in the order shown in Figure 6.1. This order reflects the relative desirability of various methods from the standpoint of environmental protection. In this hierarchy, source reduction methods are employed first. Wastes that cannot be eliminated by source reduction are managed by recycling, treatment and disposal. Of the management methods, minimization by recycling is preferred. Treatment should only be considered if source reduction and recycling have been considered and are not feasible. Treatment is performed to minimize the amount of waste and associated hazards prior to long-term storage or disposal. Disposal is not considered minimization and should be carried out as the option of last resort and only when no further minimization of the waste is feasible.

6.2.2

Occupational Health and Safety

Before waste minimization methods are implemented, the potential occupational health and safety hazards of the method must be fully evaluated. Implementation of some minimization practices may result in increased worker exposure to radiation,

62 / 6. GUIDANCE FOR SELECTION OF WASTE MINIMIZATION METHODS hazardous substances, or biohazardous agents. The following are some examples: • Recycling, treatment, and volume reduction methods often require increased handling and processing of wastes relative to direct disposal, and increase the potential exposure to workers involved in waste management operations. • Substitution of long-lived radionuclides with short-lived radionuclides allows for decay of wastes in storage and may increase the dose received by workers. For example, substitution of 125I (half-life 60.1 d) with 131I (half-life 8.04 d) results in a significantly lower holding time for decay of wastes in storage; however, the unshielded exposure rate to workers is approximately 50 percent higher due to the higher energy photons emitted. • Replacement of chemicals to avoid generation of regulated LLMW may increase toxic occupational exposures. For example, pseudocumene was widely used as a replacement for xylene (an EPA regulated chemical) in liquid scintillation counting (LSC) fluid formulations. However, pseudocumene is four times as toxic as xylene (ACGIH, 1993). • Minimization objectives may favor decreased use of disposable materials thus requiring more handing and processing of contaminated items for reuse. Practices that may be beneficial from the standpoint of minimization but which have the potential to increase worker exposure to radiation or hazardous substances should be carefully evaluated and only implemented if an analysis shows that the resulting exposure is ALARA and that the benefits exceed the risk. Maintaining exposures ALARA is a requirement of all NRC licensees.

6.2.3

Regulatory Considerations

Few federal regulations directly affect the selection of waste minimization methods, except in the case of RCRA-regulated LLMW. EPA regulations found in 40 CFR Part 268 (EPA, 2001d) require treatment of hazardous wastes before land disposal, and prescribe the method(s) of treatment to be used. Many federal regulations indicate a preference for source reduction and recycling over treatment of wastes, but do not specify the specific source reduction strategies to be employed.

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Minimization methods that involve treatment, volume reduction, or long-term storage of LLMW may require the generator to obtain a RCRA (1976) hazardous waste facility permit. The permitting process may be burdensome and costly, providing a strong incentive for most generators to avoid generation of wastes that must be treated or stored on-site. 6.2.4

Analysis and Characterization Costs

Costs associated with analytical procedures required to support minimization should be considered in selecting minimization methods. Strategies involving recycling or treating wastes usually require detailed chemical and radiological analyses of wastes to be conducted. For recycling strategies, particularly reclamation or reuse, the recycled waste must be analyzed to confirm that it meets specifications for its intended use. For treatment processes, analyses may be required to validate the process during its initial development, to monitor and control the treatment process while in progress, and to verify that the treated wastes and their residues meet internal and external (regulatory agency) requirements for storage or disposal. Analytical protocols, particularly for LLMW, are often extremely expensive and difficult due to the number of analyses that may be required and the complexity of the matrix. Few commercial laboratories are certified for analysis of LLMW (Driscoll et al., 1991). These waste analysis problems are especially daunting for laboratories, research institutions, and educational institutions which typically generate numerous, small-volume waste streams of complex composition. In some cases, the minimum quantities of waste required to conduct analytical procedures by approved methods may exceed the institution’s inventory of a particular waste. Analytical procedures can also generate significant quantities of secondary wastes which should be considered while evaluating the effectiveness of prospective waste minimization strategies for small waste streams. 6.2.5

Sequence of Minimization Steps

The minimization strategy to be applied to a waste usually requires the application of a sequence of multiple procedures which must be determined in development of the strategy. Determining the proper sequence can be complicated by conflicting objectives. For example, a generator might have to determine the sequence of

64 / 6. GUIDANCE FOR SELECTION OF WASTE MINIMIZATION METHODS steps that should be applied to a corrosive mixed-waste which contains a short-lived radionuclide, such as 131I. A risk-benefit analysis should be performed to determine if the waste should be stored for decay and then neutralized to limit potential radiation exposure during treatment; or neutralized first and then stored for decay or disposed as LLRW, eliminating the potential requirement for a RCRA storage permit.

6.2.6

On-Site Versus Off-Site Management

When evaluating various potential minimization strategies, the manager should carefully consider where the minimization procedures will be performed: at the institution where the waste was generated (on-site) or at an off-site facility. In particular, facility characteristics will affect the feasibility of the proposed strategy. Advantages and disadvantages of on-site versus off-site minimization methods are presented in Table 6.2.

6.2.7

Cost Effectiveness

Cost effectiveness should be a consideration in determining if a waste should be minimized and if so, which strategies provide the most return on investment. Determining the cost effectiveness of the various strategies is a component of recommended protocols for conducting waste minimization opportunity assessments (EPA, 1988a). EPA regulations pertaining to LLMW clearly allow for consideration of cost in determining the feasibility of minimization procedures. This is reflected in the text of the generator’s certification required on all hazardous waste manifests: If I am a large quantity generator, I certify that I have a program in place to reduce the volume and toxicity of waste generated to the degree I determined to be economically practicable and that I have selected the practicable method of treatment, storage or disposal currently available to me which minimizes the threat to human health and the environment; OR, if I am a small quantity generator, I have made a good faith effort to minimize my waste generation and select the best waste management method that is available to me and that I can afford.

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TABLE 6.2—Advantages and disadvantages of on-site versus off-site minimization methods. On-Site Management

Off-Site Management

Process and associated liabilities are under control of the generator

Process is not under control of the generator, however, generator retains liability

Shipping not required

• Shipping required • Waste must be in suitable form for shipping • Compliance with manifest system required • Risks associated with accidents, releases during shipment • LLMW can only be shipped to EPA permitted facilities • Shipping costs are incurred

Equipment, facilities, personnel, expertise may not be available

Receiving facilities should have the necessary resources

Recycling, treatment of small quantities of waste may not be cost effective or feasible

•

•

Similar wastes from multiple generators can be consolidated Economies of scale: volumes of waste may be sufficient to warrant recycling and treatment

For LLMW, EPA permits may be required for storage and treatment

Receiving facilities should already have required operating licenses and permits

Generator can direct development of minimization and management options required for institution’s waste streams

Facilities may not be available for specific wastes generated by the institution

6.2.8

Final Disposal Method

Of paramount importance in the selection of management strategies are the requirements for final disposal of the waste after treatment. If disposal is not available, or few facilities are available, additional emphasis must be placed on strategies that reduce

66 / 6. GUIDANCE FOR SELECTION OF WASTE MINIMIZATION METHODS or eliminate waste generation. If wastes must be generated, then the following disposal issues should be considered before selection of waste minimization strategies: • What are the form and packaging requirements of the disposal facility? What are the concentration limits for the various constituents that may be present in the waste? Are there any prohibited constituents? • What is or will be the cost structure for disposal? Will the unit cost of disposal be based on toxicity, activity, volume, weight, form or other criteria? • Is disposal available now or will the waste have to be placed into long-term storage pending availability of disposal? (The desired volume and form of the waste may vary significantly between storage and disposal). • If disposal is not currently available, is there a risk of treating wastes now to a form that may require reprocessing or preclude disposal when facilities become available in the future? • For regulated LLMW, EPA requires generators to select the treatment, storage or disposal method currently available which minimizes the threat to human health and the environment. It may be difficult to determine the most appropriate strategy based on disposal requirements since disposal facilities are still under development in most states and Compacts and acceptance criteria have not been determined. 6.2.9

Additional Considerations for Low-Level Mixed Waste and Low-Level Multihazardous Waste

As previously noted, LLRW that contains other hazardous or regulated constituents causing waste to meet the regulatory definitions of more than one type of waste is referred to as low level multihazardous waste (LLMHW). LLMHW that contains a combination of radioactive waste regulated under AEA (1954) and other hazardous materials regulated under RCRA (1976), or regulated under other environmental laws (e.g., TSCA, 1976) are referred to as LLMW. Generally, LLMHW is more difficult and expensive to manage and dispose of than LLRW, emphasizing a preference for source reduction as the prime strategy for LLMHW.

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Selection of strategies for minimizing LLMHW involves assessing a complex array of technical, management and regulatory factors. Reducing the risks posed to human health and the environment is the primary objective of minimization. With this objective in mind, selection of strategies for LLMHW must involve assessment of the relative risk posed by combinations of radioactive materials, hazardous chemicals or infectious agents, and the risk reduction benefits of different potential minimization and management methods. The classification of radioactive and LLMW on the basis of total risk was the subject of an NCRP Symposium (NCRP, 1995) and the subject of NCRP Report No. 139 (NCRP, 2002). Attempts to minimize the risk posed by one constituent of LLMHW may increase the risk posed by others and thus the sequence of minimization steps may be very important. Inconsistencies in the regulatory requirements for the various components of LLMHW may also complicate the selection of appropriate minimization strategies. The regulatory structure for LLMW is discussed in detail in Section 3.5. As indicated in Section 3.5, EPA and NRC each treat chemical and radiological hazards separately without any consideration for the additional hazard. Classifying a material as LLMW requires that it meets the definition as a LLRW and is either listed or has hazardous characteristics as defined by EPA. This makes LLMW unique and presents potential dual regulatory difficulties. Unless one of the hazards can be removed or an exception or exclusion can be applied, the generation of LLMW may become more difficult to manage and the waste will be subject to dual regulatory requirements. All hazardous wastes not specifically excluded from the regulations must be properly treated before disposal. However, if the generator of the hazardous waste qualifies as an exempt small quantity generator, the reporting and permit requirements applicable to the hazardous waste are generally excluded. The same exclusions afforded to conditionally exempt small quantity generators may be applied to facilities that beneficially recycle the waste. The small institutional generator must be careful to avoid the generation of LLMW whenever practical or to restrict such wastes to those amenable to available treatment,

since commercial disposal of LLMW is limited. As noted in Section 4, spent LSF containing organic solvents contaminated with small amounts of radioactive materials are the most common LLMW category generated in the institutional setting. These fluids once accounted for the largest fraction of LLMW

68 / 6. GUIDANCE FOR SELECTION OF WASTE MINIMIZATION METHODS generated by biomedical research facilities, but deregulation by NRC (1981) allowed most of them to be managed as nonradioactive hazardous wastes.4 In recent years, substitution of the volatile organic solvents in commercial LSF formulations with less hazardous chemicals has also greatly reduced the fraction of these fluids that are regulated as hazardous waste. Since overall generation of LSF wastes has been declining, much of the LLMW is now generated by other procedures, and consists primarily of mixtures of organic solvents and water contaminated with 3H or 14C labeled biomolecules and their precursors and metabolites. The characteristics of LLMW generated by various biomedical research activities 4

Under 10 CFR Part 20.2003 (NRC, 2002a), an NRC licensee may release licensed radioactive material that is readily soluble or readily dispersible biological material into any one sewerage system. Total permitted yearly activity amounts and concentration levels are detailed in the above Part 20 reference. NRC licensees can also propose license-specific deminimus concentrations for specific radionuclides, below which LLMW can be released for management as chemical waste. Note that, as a rule, NRC allows LSC fluid with less than 1.85 kBq g –1 of 3H or 14C to be disposed without regard to its radioactivity. Under RCRA (1976), certain laboratory wastewaters are excluded from the definition of hazardous waste. These provisions are found in 40 CFR Part 261.3 (a)(2)(iv)(E) (EPA, 1980a). These laboratory wastewaters, which would otherwise be regulated as a hazardous waste because they contain a listed waste containing toxic constituents, are not considered hazardous. To qualify for this exclusion, the generator must show that the laboratory wastewater discharge: is subject to regulation under either Section 402 (National Pollutant Discharge Elimination System) or Section 307(b) (pretreatment program) of the Clean Water Act (CWA, 1972), and the annualized average wastewater flow does not exceed one percent of the total wastewater flow into the headworks of the facilities wastewater treatment or pretreatment system, or provided the wastes’ combined annualized average concentration does not exceed one part per million in the headworks of the facility’s wastewater treatment or pretreatment facility. This exemption does not cover laboratory wastewaters that exhibit a RCRA hazardous characteristic (ignitable, corrosive, toxic or reactive). However, as noted in 40 CFR Part 261.3 (a)(2)(iii) (EPA, 1980a), if wastes which were listed solely for exhibiting a characteristic were mixed with other solid wastes, such as wastewater, and ceased to exhibit any characteristic, they would no longer be considered hazardous waste. Also as noted in 40 CFR Part 268.1(e)(5) (EPA, 2001d), land disposal prohibitions for hazardous characteristic waste do not apply to laboratory wastes displaying ignitability (D001), corrosivity (D003), or organic toxicity (D012 to D043) that are managed in accordance with the previously mentioned laboratory wastewater exclusion.

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at large medical research institutions have been reported (DOE, 1994a; Linins et al., 1991). 6.2.10 Special Considerations for Low-Level Multihazardous Waste That Contains Infectious Agents or is Regulated as Medical Waste Medical wastes containing radioactive materials are a type of LLMHW frequently generated by hospitals and research institutions. These wastes are of special concern because of both their radioactive and biohazardous characteristics. For example, the syringe used to administer a radiopharmaceutical to an acquired immunodeficiency syndrome patient undergoing a nuclear medicine study not only becomes LLRW, but also, much more seriously, may infect someone who is accidentally stuck by it. While waste minimization efforts can sometimes diminish the amounts of such materials requiring disposal, clearly the highest priority must be the safety of patients, medical staff, and others. It should be understood that regulation as medical waste does not necessarily mean that it is infectious. The EPA definition, as well as many state and local regulations, also includes wastes because of their objectionable aesthetic properties. Examples include anatomical wastes and research animal carcasses. Discarded sharps (items such as needles, syringes and scalpel blades) are usually considered medical waste even if they are unused. Regulations may require grinding, incineration, or other treatment to render the waste unrecognizable and prevent injuries associated with sharps. Radioactive waste incineration and disposal facilities will not commonly accept medical waste that is potentially infectious or regulated as medical waste because they do not have the required permits or appropriate waste handling systems for biohazardous materials. Conversely, commercial medical waste incinerators do not accept radioactive medical wastes because NRC or Agreement States do not license them. Generally, minimization strategies to inactivate (sterilize or disinfect) the waste must be applied at the generator’s facility before the waste can be subjected to other minimization methods or disposed. Some forms of radioactive medical waste disposal is relatively easy and minimization efforts may not be justified. For example, under current NRC rules, excreta from patients may be flushed directly into the sewage system, with no requirement for the radioactivity involved [10 CFR Part 20.2003 (NRC, 2002a)].

70 / 6. GUIDANCE FOR SELECTION OF WASTE MINIMIZATION METHODS Wastes containing or contaminated with human blood or body fluids samples require more control. Samples containing any detectable amounts of radioactive materials, for example, are considered LLRW and are typically stored for decay; thereafter, they must be disposed of properly as medical waste. It may be possible to inactivate biohazardous agents in the waste by steam autoclaving, chemical disinfection, or other forms of sterilization, but it may be necessary to take precautions to prevent contamination of the sterilization apparatus with radioactive materials. Several commonsense methods may be employed to minimize the volumes and problems of radioactive medical/biological wastes: medical procedures and biomedical experiments should be planned from the outset to account for wastes produced; biological wastes and LLRW should be kept separate from one another, to the extent possible; and substitution of short-lived isotopes (e.g., 131I for 125I) can diminish holding times significantly. One of the most common sources of LLMHW involves tracer studies using small quantities of radioactive materials in animals. Such studies generate radioactive excreta while the animal is alive and a radioactive carcass and/or animal tissues when the animal is sacrificed. All must be handled appropriately giving proper attention to both the radioactivity and the biological hazards presented by the waste. The primary biohazard posed by medical wastes is exposure of health care workers and personnel that are involved in handling wastes contaminated with blood-borne pathogens. All institutions that handle radioactive medical wastes should have a blood-borne pathogen exposure control program plan in place covering all employees that are potentially exposed. OSHA standards pertaining to controlling blood-borne pathogen exposures are presented in 29 CFR Part 1910.1030 (OHSA, 2001). Additional guidance for developing biohazardous waste management procedures and exposure control programs is available (NAS/NRC, 1989; NIH/CDC, 1993; Rekus, 1991). Treatment methods and waste forms for long-term storage and ultimate disposal of radioactive biological wastes are reviewed by DOE (1992b).

7. Waste Minimization Methods and Examples

7.1 Introduction This Section provides a description of the various methods that may be used to minimize waste, followed by specific examples for various types of waste. To the extent practicable, these methods are discussed in the order of preference, described in Section 6. However, it should be understood that many of these techniques may have applications as both source reduction and waste management strategies. In addition, other waste management techniques, such as treatment, may be a necessary step to prepare wasted for recycling. Most of the examples provided in this Section are from biomedical applications of radioactive materials. This reflects the fact that many small institutional generators are involved in biomedical activities and the growing contribution these activities are making to the generation of wastes. In California, which may be unique, it has been reported that almost 70 percent of the LLRW volume (and almost 85 percent of the radioactivity) is generated by the biomedical community (Nagle, 1994). While many of these examples are drawn from clinical and research procedures, the concepts are applicable to virtually all processes that generate LLRW.

7.2 Source Reduction Methods As previously noted, the terms waste avoidance and source reduction are often used synonymously, but have different meanings for purposes of this Report (see Section 2.2). Source reduction is specifically defined in PPA (1990) as a practice which reduces the amount of a hazardous substance from entering the waste stream or being released and thus reduces the potential hazards to public health and the environment. 71

72 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES 7.2.1

Product Changes

Product changes (substitution, conservation and reformulation) are widely used by manufacturers to minimize waste generation throughout the life cycle of their products. Since most of the intended audience of this Report is not involved in manufacturing activities, product changes are probably not methods that can be widely applied for source reduction. Methods for minimizing waste through product changes are similar to the methods described below as input material changes. 7.2.2

Source Control

Source control begins with the need for a variety of controls over the acquisition of materials that will be used in a process or in providing a service. Source control also encompasses a variety of technology changes that are oriented toward process and equipment modifications to reduce waste. These changes can range from minor changes that can be implemented in a matter of a day at low cost, to the replacement of entire processes involving large capital costs. Source control strategies may involve changes in processes; equipment, layout or piping; use of automation; and operating conditions such as flow rates, temperatures, pressures and residence times. 7.2.2.1 Acquisition Management. Institutions that are the focus of this Report rely extensively on acquisition controls to prevent unnecessary procurement of radioactive and other toxic materials to achieve source reduction objectives. Users of radioactive materials and waste management personnel work closely with the institution’s procurement department to establish acquisition controls that are effective, but not unnecessarily burdensome, and ensure that waste minimization requirements are included in all contracts and purchasing arrangements. Control of over ordering is a particularly important facet of acquisition management for waste minimization. A significant fraction of the wastes generated by some institutions consists of unused, or partially used source vials and chemicals that were ordered in quantities that significantly exceeded expected usage. In many cases these materials were purchased in bulk lots to reduce unit costs. Bulk purchasing is usually not advantageous when waste disposal costs are considered. Disposal costs often far outweigh purchase costs (ACS, 1985) and the marginal savings available in bulk discounts are no longer cost effective.

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Acquisition management strategies for source reduction may be broadly divided between controls on purchases by users and arrangements with vendors. Examples of acquisition management strategies are listed in the following sections. Generally, these strategies are applicable to both radioactive materials and hazardous chemicals. However, applying acquisition controls is more difficult for minimizing LLMW, since most materials are not ordered in a form that would be a LLMW at the time of disposal. LLMW are usually generated by the combination of hazardous chemicals and radionuclides by users after purchases are made. 7.2.2.1.1 Procurement controls • Purchase only those specific radionuclides for which definitive needs are identified and for which disposal plans are well established. • Ensure that the quantities of materials ordered are based on anticipated needs rather than unit price discounts achieved through bulk purchasing. • Target acquisition controls on radionuclides and chemicals that are the most difficult or costly to dispose. Prohibit procurement of these items, or discourage procurement by measures such as the imposition of surcharges on purchase orders to recover excessive waste management costs. • Identify radioactive materials or hazardous items for which effective substitutes are available. Establish a system to notify persons attempting to order these materials that effective substitutes exist and provide ordering information on substitutes. Restrict or prohibit acquisition of radioactive materials and hazardous substances for which substitutes have been identified. • Establish surplus material redistribution systems within the institution or between institutions with similar functions and material uses. Identify unused materials that are suitable for use or reuse, and potential users. Encourage or require acquisitions from surplus inventories. • Order radionuclides in quantities and forms that are ready to use for the identified need, avoiding the need to separate or dilute the materials for use. The wastes associated with unused stock materials and with the separation or dilution of bulk shipments can thus be avoided. • Users should consider the benefits of procuring labeled biologicals and other reagents from commercial laboratories

74 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES before attempting to do the labeling themselves. Labeling performed by commercial laboratories often requires less activity than if done on-site, and emissions and waste associated with labeling procedures are not generated on-site. The user receives only the final product, and does not have to manage and dispose of the larger quantity of the radionuclide solution which is required to perform the labeling. • Facilitate procurement of equipment, supplies and services that minimize generation of wastes such as assay kits for nonradioactive assays. • Establish affirmative procurement programs to encourage purchasing of items made from recycled materials, when available. 7.2.2.1.2 Supplier agreements • Establish agreements with vendors for limited or exact volume purchases rather than ordering radioactive materials in the minimum quantities listed in catalogs. • Arrange for timely purchasing to limit stock on hand. For most users, additional shipments, if needed, can be arranged within one working day, minimizing the need to retain an on-hand inventory for as yet unidentified future uses. • Require vendors to accept returns of unused material and spent material as a condition of purchase if they are authorized.

7.2.2.2 Input Material Changes 7.2.2.2.1 Material purification. In some cases, impurities in materials can cause significant safety and waste management problems. Identification and control of such impurities is a good waste minimization practice. LLRW example: Use of field analysis methods such as portable x-ray fluorescence equipment (Driscoll et al., 1991) for the determination of heavy metals and radioactivity can decrease the amount of samples that must be collected and processed in laboratories, thus reducing the amount of secondary wastes produced by analytical procedures.

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LLMW examples: • Solvents used in LSF may contain traces of benzene as an impurity. Benzene is a known carcinogen and allowed air concentrations in the work place are extremely low. Wastes containing as little as 0.5 mg L–1 benzene are regulated as toxicity characteristic hazardous wastes by EPA. • Trichloroacetic acid (TCA) solutions which are used in molecular biology applications such as protein precipitations usually contain chloroform, a impurity which forms by decarboxylation of this acid and its neutralization salts in aqueous solutions. The concentration of chloroform is high enough to require management as an EPA toxicity characteristic waste (DOE, 1995b; Rau, 1993).5 LLMHW example: Pharmaceuticals and biological reagents may contain trace levels of organometallic mercury compounds added as preservatives. The mercury level in some reagents may exceed 0.2 mg L–1, the concentration defining toxicity characteristic hazardous wastes. Wastes containing organometallic mercury compounds may be extremely difficult to treat and dispose. 7.2.2.2.2 Material substitution: Radioactive materials. Perhaps no other minimization method offers better potential reductions in the generation of LLRW than the increasing substitution of nonradioactive materials for radioactive materials. New technologies allowing elimination of the use of radioactive materials are being rapidly developed and applied in the United States, Japan (Nagai, 1994), and Europe. This trend is particularly evident in biomedical applications of radionuclides. The majority of the waste generated by biomedical research facilities and medical diagnostic laboratories are from various assay procedures that employ radioactive tracers. High costs and difficulties associated with disposal of radioactive waste have fostered rapid development of nonradioactive methods for the majority of common assay procedures, examples being the use of colorimetric and chemiluminescent alternatives (Party and Gershey, 1995). Nonradioactive detection methods are available and routinely used for southern and northern hybridization, colony hybridization, western blotting, restriction fragment-linked polymorphism analysis, DNA (deoxyribonucleic acid) sequencing, 5

Rau, E.H. (1993). “Results of ultraviolet peroxidation studies,” presented at the National Low-Level Waste Management Program Biomedical Mixed Waste Workshop, August 4-5, Bethesda, Maryland.

76 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES gel-retardation assays, whole-chromosome mapping, and other common procedures, with results comparable to radioactive labeling (George, 1994). Stable nuclides such as 2H and 13C replacing long-lived radioactive 3H and 14C are seeing increasing use in metabolic tracer studies. The increasing use of these nonradioactive substitutes in assays and other molecular biology procedures has the potential to totally eliminate the generation of LLRW and LLMW at some facilities. Aside from the obvious waste minimization benefits, nonradioactive methods often offer additional significant advantages to the user (Blohm and Sweet, 1994; George, 1994; Isaac, 1993): • Increased safety since radioactive materials are eliminated; • Radiolysis of proteins and other biological molecules limits the stability of radioactive labeling reagents and favors the use of nonradioactive alternatives. An example is the use of nonradioactive methods for labeling and detecting in vitro translated proteins. With nonradioactive methods, there is no degradation of the proteins due to autoradiolysis, eliminating the need to resynthesize translated products; • Shorter experimental time relative to radioactive detection techniques; and • In some cases, improved sensitivity. Where the sensitivity of the substitute method is comparable or at least acceptable, such substitution should be considered. However, the potential hazards and waste management requirements of substitutes should be thoroughly evaluated. Some nonradioactive methods (e.g., using ethidium bromide with methyl mercury oxide as a stain to visualize strands of DNA) may produce waste that is potentially more hazardous than radioactive waste. Potential hazards associated with the use and disposal of substitute materials may exceed the benefits gained from minimizing LLRW. Another disadvantage of many promising new nonradioactive methods is that expensive and dedicated equipment may be required to detect fluorescent or luminescent signals. Such high-technology approaches should be encouraged, but it is important to assess the complexities of such alternatives, where technology changes rapidly and end user productivity may be compromised due to demand or instrumentation problems. Investigator acceptance of nonradioactive methods requires that the performance of the methods compares favorably to those using radionuclides. Nonradioactive methods are generally considered not to be sensitive enough for molecular biology. Although this

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may be true for demanding applications (e.g., analysis of single copy genes), nonradioactive approaches are suitable for many widely-used procedures. By judicious choice of application, significant reductions in waste can be achieved and researchers will begin to use them (NIH, 1996). Key to increasing the use of nonradioactive methods will be the establishment of mechanisms for disseminating appropriate information and protocols to users of radioactive materials in assay techniques. The institution’s training programs should provide opportunities to its scientists to learn about state-of-the-art, nonradioactive alternatives in an organized manner (NIH, 1996). LLRW examples: • Party and Gershey (1995) have published a compilation of nonradioactive methods for use in biomedical procedures. • Silver-based staining systems are available to replace radioactive materials in DNA sequencing (Wade-Evans, 1996). This system may be less expensive than fluorescent and chemiluminescent techniques; however, it may require disposal as hazardous waste if the concentration of silver exceeds 5 mg L–1. Use of silver stains in conjunction with radioactive methods may yield LLMW (DOE, 1995a). • Techniques for direct sequencing of polymerase chain reaction products are of central importance to contemporary research in molecular biology and genetics. Polymerase chain reaction sequencing methods are now available that avoid the use of radionuclides (Letocart et al., 1997; Waha et al., 1996). LLMW examples: • Washing steps involved in radioactive kinase assay procedures produce significant quantities of liquid radioactive waste. A nonradioactive method of performing the assays, which is now commercially available, has several advantages over the radioactive methods and eliminates generation of radioactive waste (Lipton et al., 1994). • Nonradioactive methods are available and routinely used for southern and northern hybridization, colony hybridization, western blotting, restriction fragment-linked polymorphism analysis, DNA sequencing, gel-retardation assays, whole-chromosome mapping, and other common procedures,

78 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES with results comparable to radioactive labeling (George, 1994). When radioactive methods are used, these procedures may generate LLMW. • Assays to detect protein expression such as the ribonuclease protein assay (RPA) are usually required to study physiological interactions between cells. RPA methods using radioactive materials (32P) generate liquid LLMW. A new, rapid, nonradioactive (digoxigenin) RPA has been developed (Plath et al., 1996) which eliminates generation of LLMW. The speed of the dioxigenin detection method is also a remarkable advantage over radioactive assays. • Early immunoassays for tumor necrosis factor alpha used radioactive tracers that presented handling problems and were costly to dispose of as LLRW. Subsequently, nonradioactive enzyme immunoassay methods were developed that did not require use of radioactive materials, however, the wastes from the first generation of these methods were also costly to dispose as hazardous waste. Materials used in these procedures were preserved with thimerosal, a mercury compound. These kits also contained o-phenylene diamine, a suspected carcinogen, which was used as chromogen for development of colored end products required for the assay. These toxic chemicals have been removed from the materials used in “third generation” of nonradioactive enzymine innumoassay methods (Millett et al., 1994). • An infrared fluorescent method for labeling DNA molecules and facilitating their detection with an automated DNA sequencing and analysis system has been developed (Steffens et al., 1995). The method is sensitive and avoids the use of radioactive materials.

LLMHW examples: Radioactive methods used in clinical applications involving blood, tissues, and other potentially infectious material generate large quantities of waste. For example, medical technicians perform about 100 million radioimmunoassay procedures per year (Nagle, 1994). Replacement by nonradioactive methods eliminates generation of LLMHW. The following are some of the many examples of nonradioactive substitutes in clinical procedures. • Reverse transcriptase (RT) assays are used to detect viruses such as hepatitis B and the human immunodeficiency virus

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(HIV). The usual method of measuring RT activity involves incorporation of 3H thymidine into acid-precipitable materials. Assays for RT activity in viruses such as HIV are performed in cell cultures. The method is tedious to perform, and results in the generation of potentially infectious LLMW containing TCA which is difficult to detoxify and LSC fluids. The use of nonradiometric RT assays (Enzyme Linked Oligonucleotide Sorbent Assay), now commercially available in kit form, eliminates generation of these wastes. • The mixed lymphocyte reaction is an important assay used clinically in bone grafting procedures to determine compatibility of donors and patients. Historically, the assay used incorporation of tritiated thymidine to detect T-cell proliferation; however, the method generated significant amounts of radioactive waste. A new, nonradioactive method was developed primarily to avoid generation of radioactive waste. This new method was found to have additional significant advantages over the old method. The nonradioactive assay is less hazardous to laboratory personnel, less expensive, and requires much less final processing than the radioactive assay (VanBuskirk et al., 1995). • Nonradioactive methods have been developed to replace radioactive methods used to detect antigens on human blood cells (Flesch et al., 1995). • In situ hybridization (ISH) is a widely used technique that has great power in many common biomedical applications (Durrant, 1996), including diagnosis of viral infections (McQuaid et al., 1991), chromosome analysis (Price, 1993), and mRNA analysis (Mitchell et al., 1993). All of these applications may generate LLMHW if traditional radioactive labels are used to prepare the probes required to carry out ISH procedures. Recently, nonradioactive probes for ISH have become more popular (Durrant, 1996) and their use will prevent generation of LLMHW.

7.2.2.2.3 Material substitution: Radioactive microspheres. Radiolabeled microsphere particles have been used for measurement of regional blood flow for over 25 y (Rudolph and Heymann, 1967, cited in Kolenda et al., 1994). The use of radioactive microspheres for flow measurement, however, is fast becoming inaccessible to investigators due to radioactive waste disposal costs, safety concerns, and limitations in flexibility of use (Kolenda et al., 1994; Van

80 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES Oosterhout et al., 1995). Wastes containing microspheres are difficult to manage and may not be acceptable at incineration facilities. Biological wastes containing radioactive microspheres were found to be a major contributor to the total waste volume at a large university-hospital complex and became a top priority for minimization (Emery et al., 1992). Nonradioactive microspheres are now commercially available for regional blood flow measurement (Kolena et al., 1994). Fluorescently labeled microspheres are now considered reliable alternatives to radioactive microspheres in several organ systems (Austin et al., 1993; Glenny et al., 1993). A disadvantage of nonradioactive microspheres has been that processing of samples is time-consuming and complex. Recently, simplified processing methods have been developed and validated for measuring organ profusion (Van Oosterhout et al., 1995).

7.2.2.2.4 Material substitution: Short-lived radionuclides. When the use of radioactive materials cannot be eliminated, it is often possible to substitute radionuclides that are less potent, can be held for decay, or are otherwise easier to treat on-site. Substitution with short-lived radionuclides suitable for decay-in-storage waste management is an important option to avoid the generation of waste contaminated with long-lived radionuclides that require off-site disposal. Refer to Section 7.3.2.1 for additional information on decay-in-storage and examples.

LLRW example: 131I or even 123I may be substituted for 125I in some uses, and 32P or 33P may be used in place of 35S in others. While waste from both 125I and 35S can be managed by decay-in-storage, the much shorter-lived substitutes can reduce management requirements and storage time, resulting in less storage and control space. LLMW example: Few options exist for treatment and disposal of LLMW containing long-lived radionuclides. If it is necessary to generate a LLMW, substitution using short-lived radionuclides will greatly alleviate potential waste management problems. The use of short-lived radionuclides permits management of LLMW as nonradioactive hazardous waste after decay; allowing access to wide variety of hazardous waste treatment technologies and commercial facilities (see Section 7.3.2.1).

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LLMHW examples: • Use of short-lived radionuclides minimizes the time required to store perishable/putresible wastes and biological wastes. After decay, the waste may be treated and disposed as nonradioactive medical waste. Because most of the radionuclides used for patient diagnosis or therapy are short lived, it is usually possible to hold these wastes for decay and then dispose of the waste as nonradioactive medical waste. • Substitution of microspheres containing long-lived radionuclides with shorter half-life radionuclides (such as 188Re) is a useful strategy to alleviate problems associated with disposal of animal carcasses containing radioactive microspheres (Emery et al., 1992).

7.2.2.2.5 Material substitution: Hazardous chemicals. Replacement of hazardous chemicals with less hazardous or nonhazardous materials improves safety and can eliminate or reduce generation of LLMW or chemical contaminants in LLRW that can release toxic emissions during waste management operations. Chemical substitution efforts should be targeted on chemicals, such as organic mercury compounds and halogenated acids, which produce wastes which are particularly difficult to manage. Before making substitutions, all hazards posed by the substitute material should be considered. Aside from short-term safety and disposal considerations, the characteristics of substitute materials in long-term storage should also be considered. Most LLMW streams have few, if any, disposal options and require long-term storage. LLRW examples: • Polyvinyl chloride (PVC) based plastics are used in a wide variety of common materials such as packaging, floor tiles, hoses, insulation for wires and cables, upholstery, footwear, and clothing. In the laboratories and medical facilities, PVC is used in tubing, gloves, reusable bench liners, blood bags, electrophoresis gel boxes, hybridization cassettes, and many other devices. The use of tubing and other items made from PVC plastics in applications involving potential contact with radioactive materials should be avoided. PVC plastics

82 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES contain high concentrations of plasticizers, primarily diethylhexyl phthalate (DEHP), which has been associated with reproductive system toxicity, hepatocarcinogenesis, and other toxic effects. Under normal conditions of use, DEHP leaches out of PVC products. Phthalate concentrations in liquids contained in PVC may exceed permissible limits in wastewater discharges. Leaching may be accelerated by high temperatures or the presence of organic solvents. Disposal of PVC items that cannot be decontaminated may also be difficult and costly. Incineration facilities may limit or not accept wastes containing PVC plastics because combustion of PVC produces emissions of hydrogen chloride that may damage incineration equipment and must be maintained at low levels to meet air pollution control requirements. Incomplete or uncontrolled combustion of PVC may release highly toxic chlorinated organic compounds, and a large percentage of the phthalates to the atmosphere. Phthalates may also be released to the air or aquatic environment after disposal in landfills (WHO, 1992). Phthalate free, non-PVC plastic tubing is available for virtually all applications involving radioactive materials, and substitute materials have been specifically approved for disposal at radioactive waste incineration facilities. • Fluorinated plastics are used in many applications ranging from laboratory ware to bench liners. Under normal conditions of use, they offer many advantages including high chemical resistance and cleanability. However, incineration of these materials produces hydrogen fluoride and other toxic compounds. Substitution with nonhalogenated plastics should be considered in situations where disposal by incineration is required.

LLMW examples: • LSF or “cocktails” may contain numerous organic chemicals that may contribute to air and water pollution if not properly handled, treated and disposed. Toluene and xylene, which were the major constituents of older LSC formulations, are listed by EPA as hazardous waste and banned from land disposal. Cocktail formulations that contain hazardous solvents must be recycled or disposed at EPA permitted fuel blending facilities or incinerators. Most suppliers

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now offer nonflammable cocktail formulations in which the volatile solvents have been replaced by various detergents and alkylbenzene compounds. These replacement compounds are not regulated as hazardous wastes by EPA nor are they included on lists of compounds prohibited from discharge to the sanitary sewerage system. Klein and Gershey (1990) and others have reviewed several of the less hazardous, biodegradable cocktails and found them to be comparable to their predecessors in terms of efficiency, sample capacity and viscosity. Some of the newer, more environmentally acceptable scintillation fluids have been approved for discharge into sanitary sewerage systems without treatment. For small users, emptying vials of such material into the sanitary sewerage after use may be an acceptable method of disposal, and some advantages to all users in the conversion to these substitutes exist since the chemicals are less volatile, less toxic, and reduce hazards during the initial sample preparation and use. Large users have found that contractors can accept vials containing these fluids for incineration thus providing a practical, cost effective, disposal method and reduced occupational heath hazards. • Long-term storage of radioactive flammable solvents, requires extensive precautions and fire prevention and control systems which may be very costly to install and maintain. Replacement of flammable organic solvents with low flammability solvents may be an option to reduce fire hazards. Nonflammable solvent mixtures often contain chlorinated solvents that are especially difficult to treat and may pose serious health and environmental hazards during long-term storage. LLMW containing chlorinated solvents may produce and release phosgene, a highly toxic gas. If long-term storage is necessary, chlorinated solvents should be stored in darkened glass bottles to prevent photodegradation and potential generation of phosgene (Linins et al., 1991). • The use of chromosulfuric acid based formulations for critical cleaning of laboratory glassware contaminated with radioactive materials should be avoided. Spent cleaning solutions and rinsates are LLMW (chromium toxicity characteristic D007, and corrosive D002). Detergents or other nonhazardous alternatives should be used for critical cleaning applications.

84 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES • All industries that have neutron or gamma sources, and in some cases, higher energy beta sources, need shielding from time to time for personnel protection, general area radiation reduction, packaging radioisotopes, and other shielding needs. Because of its density, the universal shielding material of choice has been lead. The major negative aspect of using lead as shielding is the LLMW generated when the lead becomes contaminated with radioactive materials. Lead containers and shielding should not be used except when there are no suitable substitute materials. In many cases steel or other lower toxicity alloys can be used as shielding materials in place of lead. If lead should be used it should be protected from contamination by radioactive materials. In one explosive testing laboratory, replacement of lead weights with steel weights, and use of protective barriers to protect lead shielding from fragmentation resulted in savings of approximately $500,000 in the first year of implementation (Gonzalez et al., 1993). • Membranes made of nitrocellulose are a well recognized fire hazard and can be ignited at most ambient temperatures likely to be encountered in operating laboratories. Nitrocellulose membranes from these blotting procedures may be contaminated with biohazardous agents, require special handling, shipping and storage and have few, if any, disposal options. For most laboratories, the only option is to hold the nitrocellulose waste for decay-in-storage, inactivate any biohazardous agents present, and then manage the material as a hazardous waste. Autoclaves may be used to inactivate the biohazardous agents if the radionuclides present are not likely to be volatilized. Precautions must also be taken to ensure that the autoclaves are operating properly in accordance with manufacturer’s recommendations, and that the nitrocellulose membranes are not allowed to become dry during the autoclave cycle (CDC, 1985a). Nitrocellulose paper may be highly reactive and can detonate or explode when heated under the confinement conditions present in the closed chamber of an autoclave (CDC, 1985b). Alternately, chemical disinfectants such as sodium hypochlorite solutions may be used to inactivate the biohazardous agents (CDC, 1985a; 1985b). Substitution of nitrocellulose with membranes made from microporus polyvinylidene difluoride, a nonflammable material, eliminates the potential to generate these difficult to manage LLMHW. It is urged that

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use of these substitute materials be considered for use in applications involving long-lived radionuclides. Mixtures of phenol and chloroform have been routinely used in molecular biology laboratories to extract nucleic acids from radiolabeled biological materials, and denature proteins that remain after treatment with enzymes (Linins et al., 1991). The spent solutions from these extraction procedures are poisonous, corrosive, and difficult to treat; and comprise a significant fraction of the wastes generated by biomedical research facilities. New extraction procedures are now available in kit form from several suppliers. These procedures should be used whenever extractions involve radioactive materials if they provide satisfactory or enhanced results. For example, kits that do not contain phenol/ chloroform extractants are available for performing RPA. These kits proved to be superior for radioactive assays without loss of performance (Plath et al., 1996). The research staff at a DOE facility was using 1,1,1-trichloroethane with rags to clean manipulator parts for use in hot cells, resulting in the generation of two drums of mixed waste per year. Replacement of the solvent with a nonhazardous degreaser eliminated the LLMW (Degan and Selby, 1993). Methanol is frequently used in molecular biology for processing electrophoresis gels and various blotting techniques for radiolabeled proteins and nucleic acids. Methanol can be replaced with ethanol in some systems for final membrane washing (DOE, 1995b). Substitution of methanol with ethanol reduces potential toxicity hazards to workers, and eliminates generation of spent methanol, an EPA-listed hazardous waste. Non-ignitable concentrations of ethanol are not regulated as hazardous waste. Ignitable ethanol solutions will be a characteristic waste rather than a listed waste, which has fewer disposal options. In some cases, rinsing electrophoresis gels with deionized water rather than alcohols has been effective and has eliminated generation of LLMW (DOE, 1995b). Aerosols generated from DEHP, commonly referred to as dioctyl phthalate (DOP), have been routinely used for “in place” testing of high-efficiency particulate air (HEPA) filters. Because these filters are often used to remove radioactive particulate matter, filters tested with DOP may require management as LLMW. Nonhazardous substitutes for DOP

86 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES in the testing procedure are now available. Use of these substitutes prevents generation of LLMW6 and eliminates potential occupational exposures to DOP, a suspected human carcinogen (Klein, 1995). • DOP is sometimes used as vacuum pump oil and is an EPA-listed hazardous waste. Vacuum pump oils can become contaminated with radioactive materials, particularly volatile radionuclides such as 35S and 14C. The use of petroleum-based oils as substitutes for phthalates reduces or eliminates the potential for LLMW generation. • A 3:2 mixture of dibutyl phthalate and DOP is being used to separate bound ligands from free ligands in receptor binding assays with 125I (Zurawski et al., 1990). Substitution of the phthalate mixture with non-phthalate oils as previously used in the procedure (Zurawski and Zurawski, 1989) will eliminate generation of LLMW.6 • Non-solvent based paints should be used in areas that can become radioactivity contaminated. LLMHW example: Consider replacing tissue fixatives and disinfectants that may contain hazardous chemicals with less hazardous, easier to dispose substitutes. Some disinfectants contain phenolic compounds, aldehydes, or other toxic compounds that may require management of the inactivated waste as LLMW.

7.2.2.2.6 Material substitution: Biohazardous materials. In some situations it may be possible to reduce the potential biohazards of radioactive wastes by using agents or materials that are less infectious. The suitability of substitutes will be highly variable depending on the specific situation. Some general strategies that may be considered are as follows: • Using organisms that are less virulent or nonpathogenic; • Using organisms or biological materials that can be easily inactivated or treated by methods that will be compatible with radioactive materials and chemicals in the waste; • Working with animal pathogens rather than human pathogens; 6

If discarded as pure commercial products, these phthalate compounds are regulated by EPA as listed toxic hazardous wastes. After use, or as mixtures they may not be regulated as hazardous or LLMW because they do not meet the definition of a hazardous waste.

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• Working with animal tissues and body fluids rather than materials of human origin; and • Avoiding generation of wastes that will favor growth of pathogenic organisms. 7.2.2.3 Technology Changes 7.2.2.3.1 Process changes: Equipment, piping or layout changes. Changes in processes that focus on equipment, piping or layout modifications can often result in significant waste minimization benefits. LLRW examples: • Substitution of aluminum or other easily cleanable materials for wood components will enable them to be decontaminated for reuse. Several other secondary issues need to be considered when substituting the aluminum materials. Aluminum is a soft metal that could have the radioactive contaminant ground into the surface. This presents decontamination difficulties that may require more aggressive techniques such as chemical cleaning or spot abrasive decontamination. Both of these additional considerations need to be evaluated to determine the potential secondary waste, cost and exposure. Chemical cleaning may result in the generation of relatively large quantities of secondary waste which may involve hazardous materials and/or hazardous waste. • Use of high-pressure microwave dissolution apparatus is being studied as a method to reduce secondary waste generation from gross alpha and beta measurements of soils and other samples (Green et al., 1996). LLMW examples: • LSC wastes can be virtually eliminated by using dry counting procedures. Wonderly (1989), Hawkins (1991), and others have demonstrated that improved solid scintillation counting methods now offer counting performance similar to LSC for nonvolatile substrates. Solid scintillation counting requires no new instrumentation. The obvious advantages of solid scintillation counting are great reductions in waste disposal volumes and costs, reduced health hazards to the

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user, reduced fire hazards to the institution, and increased convenience to the user (Wonderly, 1989). Changing LSC methods to those that do not involve the use of vials, can significantly reduce waste volumes. An alternative to vials is a counter design based on a flat-bed geometry in which multiple samples are deposited within discrete areas on a filter sheet. The filter is dried, sealed in a plastic bag with a small quantity of scintillant, and counted, eliminating the need for a separate vial for each sample. Using 12 mL of scintillant per 96 samples, some 5,000 samples can be contained in a 10 cm cube, giving a reduction of more than 95 percent in the waste volume and a proportional reduction in the cost of scintillant and plastic consumables (Warner and Potter, 1986; Warner et al., 1985). New techniques employing laser/reusable TLDs are also now available which eliminate LSF and most solid wastes associated with use of plastic scintillators. Systems using storage phosphor imaging plates and digital readers have numerous applications in thin layer chromatography, autoradiography of electrophoresis gels and DNA adducts, scintillation counting, and other common molecular biology procedures. Use of these new imaging plate systems has the following major potential waste minimization benefits over conventional x-ray film imaging techniques (Hamaoka, 1990; Kanekal et al., 1995). - The higher sensitivity of the technique allows the use of lower quantities of radionuclides; - Sample preparation and LSC procedures that generate LLMW are avoided; and - Toxic liquid wastes associated with developing and fixing traditional x-ray films are eliminated. Systems for recovering silver from photo-processing wastes and discarded film are no longer required. Toxic flammable liquid wastes, from high performance liquid chromatography (HPLC) and HPLC in combination with LSC, are one of the largest sources of listed LLMW from some biomedical research facilities such as NIH (DOE, 1995a). Minor equipment modifications can result in significant reductions in the volumes of toxic ignitable LLMW from these procedures. Much of the waste related to HPLC is generated between sample injections, during equipment start up, or other periods when only clean solvent is flowing through the unit.

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Switching systems are now commercially available that can be installed on HPLC equipment to automatically detect and divert flows of uncontaminated carrier solvents from waste back into the system for direct reuse. Replacement of large bore columns with small bore columns has also been used to reduce the carrier solvent flow rates. These modifications can significantly reduce solvent procurement costs and waste volumes. Wastes from a washing procedure for radiolabeled cells that uses TCA are often collected by aspiration into a flask. Installation of a valve and bypass in the aspirator line allows diversion of wastes from the washing steps that did not involve this acid into a separate flask for collection of aqueous LLRW. This simple equipment modification can significantly reduce the volume of waste that requires management as LLMW. Use of improved electrophoresis gel drying equipment can reduce the need for fixing procedures that generate liquid LLMW (DOE, 1995b). Less waste containing toxic chemicals and 32P will usually be generated by changing to a horizontal system for running electrophoresis gels (Plath et al., 1996). A preliminary step for the determination of RCRA regulated semi-volatile compounds in solid matrices such as soil and sludge samples involves Soxhlet extractions with organic solvents. In most cases a microwave-assisted extraction technique method can be used which is as efficient as the conventional Soxhlet method. Use of microwave-assisted extraction techniques reduces use of solvents by from 30 to 300 mL per extraction (Green et al., 1996). A sensitive protein phosphatase assay has been developed that reduces generation of LLRW and eliminates generation of washing solutions which may contain TCA (Kim and Matthews, 1993).

7.2.2.3.2 Process changes: Additional automation. Automation of processes previously done manually can result in large reductions in the volumes of waste generated. LLRW example: Cytotoxicity assays using 51Cr involve processing and reading large numbers of microplates. The use of automated

90 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES equipment (96 well beta counters) decreases the volume of waste generated (Hillman et al., 1993). LLMW examples: • DNA sequencing techniques are major sources of LLRW and LLMW from biomedical research facilities. Large scale sequencing projects require technically easy, highly automated methods. Fortunately, automation has the potential to significantly reduce the volume of wastes generated and many of the large-scale automated procedures in use or under development employ nonradioactive techniques (DOE, 1995b; Rolfs and Weber, 1994). • Harvesting procedures for radiolabeled cells generate LLMW. The use of larger capacity cell harvesting equipment may reduce the volume of wastes generated per procedure. A 96 unit harvester uses the same quantity of reagents as a 16 unit harvester, but can process six times more samples in a single batch (DOE, 1995a). • The most common method of measuring cell proliferation involves the incorporation of tritiated thymidine in the DNA of dividing cells. Processing and counting of the labeled cells generates LLMW. The use of multiwell counting plates yields more rapid results and minimizes generation of wastes (Briers and Desmaretz, 1993). • Automated, microrobotic systems have been devised to collect, drain and wash LSC vials (Maeda and Yamada, 1985).

7.2.2.3.3 Process changes: Changes in operational settings; microscale techniques. Fischer et al. (1991) found the use of microanalytical techniques to be one of the most highly rated methods in their evaluation of potential waste minimization methods for generators of LLRW. Microscale techniques have many safety and cost advantages; however, the primary force driving conversions from larger scale processes is the cost of waste disposal. Microscale techniques are widely applied and bring major waste minimization benefits in health care and commercial institutions where numerous analyses and other repetitive procedures are required. Over the past two decades, microscale technology laboratory protocols for biomedical research progressively scaled down from a liter to a milliliter to a microliter scale, reducing both reagent cost and the volume and radioactivity of resulting wastes

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(Linins et al., 1991). Microanalysis methods are now being investigated by DOE to reduce generation of secondary wastes from waste characterization procedures (Green et al., 1994). In educational and research institutions where many different and nonstandard procedures may be used, across-the-board implementation of microscale techniques is more difficult (Fischer et al., 1991). LLMW examples: • Replacement of conventional LSF vials with smaller vials can significantly reduce the waste volume, sample preparation, and disposal costs. Elliott (1993) reported that little or no performance loss occurs from using 1 or 2 mL microcentrifuge tubes in place of 7 or 20 mL vials during counting of aqueous or filter samples in microcentrifuge tubes. This procedure can result in a 50 to 75 percent reduction in waste volume. Counting LSC samples on 96 well plates, each with a capacity of 0.2 mL rather than 20 mL standard vials, results in a 35:1 reduction in waste generation. • Continuous fraction collectors are now available which can be used to collect and fix extremely small sample volumes from HPLC, fractionators, or other sources on solid substrates such as filter paper or membrane materials. The substrate is wrapped around a rotating cylinder which can then be read with various imaging detectors, scintillation, etc. The system uses extremely small sample volumes, and no vials or tubes are required which minimize wastes and consumables. LLMHW example: The use of micro-analytical techniques is already a standard practice in most hospitals. Therefore, the potential for additional reductions in generation of wastes from these sources by use of these techniques may be limited (Fischer et al., 1991). 7.2.2.4 Good Operating Practices 7.2.2.4.1 Procedural measures. Significant reductions in waste generation can often be achieved by relatively minor changes in processes and procedures. A recent assessment of minimization options for LLMW generated by biomedical research procedures (DOE, 1995b) found that minimization methods requiring only

92 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES minor process and procedural changes were favored by investigators because they required less costly validation and could generally be implemented with only a minor investment of time and lost research productivity. LLRW examples: • Absorbent materials have been widely used to control radioactive liquids from the laboratory bench to the animal cage. Unfortunately, such absorbent use adds significant bulk to the waste stream, and may even, as in animal work, result in the creation of LLMHWs. Liquids held without absorbent may be better managed by holding for full or partial decay and flushing into the sanitary sewerage, if such discharges are allowed. • Animal bedding, with absorbed radioactive excreta, provides not only a difficult bulk problem, but creates special handling requirements for the excreta. Tracer studies with 3H or 14C may result in deregulated concentrations of these nuclides in the animal (less than 1.85 kBq), but deregulated concentrations are not applicable to contaminated bedding. The use of metabolic cages in which no bedding is used and all excreta are collected may be preferable. The excreta can be flushed under controlled conditions avoiding a difficult waste form to manage and dispose. In addition, the cages are easily decontaminated. • Plastic-backed liners have been extensively used to control the spread of contamination on the bench top, but it may result in a deposit of contamination that is readily transferable to other uncontaminated materials. The liner can also add significant bulk to the waste stream. A growing trend is to convert to working in laboratory work trays without absorbent material. Non-tip trays are now available with a washable liner, designed such that liquid spills may be easily recovered even from the corners. This provides for recovery and reuse of spilled radionuclides plus the capability of decontaminating the work surface at the sink between uses. LLMW examples: • Liquid wastes from rinsing and fixing electrophoresis gels are one of the highest volume LLMW generated at biomedical research facilities. Typically, these wastes contain radioactive materials and aqueous mixtures of methanol,

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ethanol, acetic acid, TCA, and chloroform (a decarboxylation product of TCA). Minor changes in gel processing procedures can greatly reduce or eliminate these LLMW. For example, the volumes of acetic acid/methanol solutions in washing and fixation procedures can be greatly reduced with little or no adverse affects on the procedure (DOE, 1995b). “Blasting” with pelletized dry ice can be used to remove paints and coatings from contaminated surfaces in place of conventional solvent stripping methods (Owens, 1992). Redesign cleaning processes for parts by incorporating ultrasonic cleaning or pelletized dry ice blasting methods instead of cleaning the parts with methylchloroform (Owens, 1992). When cleaning shields with leaded glass components, such as those used in radiopharmacies, commercial decontamination solutions containing ethylenediamine tetraacetic acid should be used carefully. Although this acid is effective in removing radioactive particles from surfaces by sequestering and suspending the particles, it can chelate the lead in the glass, producing a cloudy film on the glass. Cleaning solutions from this process may have to be managed as LLMW because of the presence of solubilized lead. Alternative cleaners are available (Heller, 1996). Statistical methods can be used to reduce the number of sample analyses required to support radiation safety programs and the generation of secondary wastes. For example, radiation surveillance programs at institutions use wipe test sampling to indicate the presence of removable contamination on surfaces. Analysis of these samples generates significant volumes of liquid scintillation wastes. Expected value statistics can be applied to modify the sampling and analysis procedure to reduce the number of analyses required and the wastes associated with the analyses (Emery, 1997).

LLMHW example: In general, for patient care there is a preference for reusable items, rather than disposable items, involving the use of radioactive materials.

7.2.2.4.2 Loss prevention. Emissions and losses of radioactive materials may occur under normal process operating conditions

94 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES through leakage, purge and volatilization. Controlling these fugitive emissions and losses reduces pollution and may minimize generation of wastes associated with containment and clean-up of released materials. LLRW example: Classical laboratory methods of working with tritium gas such as those employed in high specific activity labeling procedures involve significant (80 to 90 percent) losses of the gas to the atmosphere. These losses can be efficiently controlled by use of manifold systems that capture the tritium on depleted uranium (Rapkin et al., 1995). 7.2.2.4.3 Waste segregation. Adherence to a well developed waste segregation plan is a critical component of a waste minimization program. Proper segregation of radioactive and hazardous materials during processing and after generation as waste has the following benefits: • Allows reuse of materials that are still in usable condition; • Optimizes potential for recovery of materials; • Prevents mixing of radioactive waste with nonradioactive waste, reducing LLRW volumes that may require off-site disposal; and • Prevents unnecessary generation of mixed and multihazard wastes which may be very difficult to treat and dispose. Segregation practices should be based on the following principles: • Preventing mixing of materials that are chemically incompatible; • Avoid mixing and commingling wastes that should be managed separately; • Maximizing potential reuse and recovery of materials; • Collecting materials in the most optimal form and composition for treatment; • Feasibility—facilitating management by the user: groups should be well defined, not unnecessarily complex, requiring excessive number of containers, sorting, handling, etc.; and • Properly label waste containers. Ensure that labels provide all of the information necessary for hazard communication and to make waste management decisions. Labels should include generator identification (name, organization, building, room, telephone number, date, volume of waste, radionuclides and activities, form, unabbreviated chemical and

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biological names, estimated concentrations of major chemical constituents, and all hazardous compounds regardless of concentration). 7.2.2.4.4 Waste segregation: Chemical compatibility. A paramount concern in establishing segregation groups is to keep chemically incompatible wastes such as oxidizers and organic solvents separate. Violent chemical reactions, releases of toxic gases, fires and explosions can result when chemically incompatible LLMW are combined. The potential for incompatibility reactions is highest in laboratory operations, where a large variety of chemicals may be in use and there are centralized areas for collection of wastes. Refer to the manufacturer’s Material Safety Data Sheets and standard references such as Bretherick’s (Urben, 1999) and NAS/NRC (1995) for information on chemical incompatibility. Another potential consequence of chemical incompatibility is the release of volatile radioactive materials from wastes. Literature on this subject is scant. 7.2.2.4.5 Waste segregation: Radioactive/nonradioactive wastes LLRW example: Segregation of solid wastes from laboratory operations can greatly reduce the amount of waste that must be disposed off-site. A segregation scheme adapted from that described by Ring et al. (1993) follows: • Collect wastes known to be contaminated separately from wastes potentially not contaminated. Upon completion of experiment, waste that is potentially not contaminated should be surveyed for radioactive material content with an appropriate instrument. If not contaminated, it can be disposed with conventional solid waste and any contaminated waste is managed as LLRW. • Paper and plastic potentially contaminated with 14C or 3H should be assumed to be contaminated because it is usually not feasible to conduct assays and should be disposed as LLRW.

7.2.2.4.6 Waste segregation: Long/short half-life wastes. Short-lived radionuclides should be segregated from long-lived radionuclides, whenever possible. Decay-in-storage should be used for the short-lived radionuclides to minimize the waste that must ultimately be shipped off-site for disposal.

96 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES LLRW example: Nuclear medicine programs have nearly eliminated the generation of LLRW that requires off-site disposal by segregating their wastes and holding all but the long-lived sealed sources for decay (Heller, 1996). Research laboratories are now increasingly emphasizing proper segregation of LLRW in the laboratory, which is the place where such segregation is most practical. Most institutions that generate LLRW segregate by nuclide or half-life, then store for at least 10 half-lives before monitoring for disposal as normal trash. Due to uncertainties in LLRW disposal, it is becoming advantageous to store-for-decay radionuclides with half-lives up to 120 d, depending on the type and quantity of such waste generated. NRC regulations permit decay-in-storage of isotopes with less than a 65 d half-life [10 CFR Part 35.92 (NRC, 1994a; 2002b)]. For isotopes greater than a 65 d half-life, a license amendment is required. In radiopharmacies that generate sufficient volumes of waste it may be desirable to segregate decayable wastes into groups of radionuclides with similar half-lives. Segregation groupings of commonly used medical isotopes are presented in Heller (1996). Waste should be carefully screened prior to disposal to ensure that there are no trace quantities of long-lived radionuclides present. 7.2.2.4.7 Waste segregation: Deregulated/non-deregulated wastes. NRC and most Agreement State regulations provide for disposal under restricted conditions of certain radionuclides if the concentration is below the regulatory limit. LLRW example: LLRW containing less than 1,850 Bq –1 of 14C or 3H and which are soluble and biologically readily dispersible can be disposed using sanitary sewerage discharge limits under 10 CFR Part 20 (NRC, 2002a). For example, deregulated spent scintillation cocktails that do not contain hazardous wastes or priority pollutants can usually be discharged to the sanitary sewerage system. 7.2.2.4.8 Waste segregation: Deregulated liquid scintillation counting wastes from non-deregulated wastes. NRC and most Agreement State regulations permit very low-level LSC wastes (vials and bulk liquids containing ≤1,850 Bq mL–1 of 3H or 14C) to be disposed without regard to their radioactivity. Because there are more disposal options for deregulated scintillation cocktail wastes,

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they should be collected and disposed separately from non-deregulated cocktails and other LLMW. This deregulated level represents 1,667 Bq cm–3 in the counting media (significantly more activity than typically needed in analytical samples) and since this upper limit may be averaged over the vial batch, most users find this limit to be a practical relaxation of the regulation and the scintillation waste may be managed as nonradioactive hazardous waste only. The same contractors who accept radioactive scintillation wastes for processing and burning at fuel recovery facilities usually accept deregulated scintillation vials at a reduced price. 7.2.2.4.9 Waste segregation: Deregulated animal carcass wastes from excreta and other radioactive biohazardous wastes. NRC and most Agreement State regulations permit very low-level animal carcasses (containing ≤1,850 Bq –1 of 3H or 14C) to be disposed without regard to their radioactivity, provided that they are not used for human consumption. Carcasses that meet this deregulated level should be collected and handled separately from other radioactive carcasses to reduce the amount that must be disposed as LLRW. In most cases, deregulated carcasses can be disposed as nonradioactive medical waste. It is important to understand that this deregulation applies only to the animal carcasses and not to the excreta. Excreta from animals may be disposed directly into the sanitary sewerage within the discharge limits. Animals can be housed in metabolic cages so the excreta can be collected in a form suitable for direct flushing rather than absorbing it in the tray of a conventional animal cage. 7.2.2.4.10 Waste segregation: Radioactive/hazardous wastes. Probably the most important institutional strategy for reducing or preventing generation of LLMW is to prevent cross contamination and unnecessary commingling between hazardous wastes and radioactive wastes. Where hazardous chemicals and radioactive materials are used in the same laboratory or work area, strict segregation requirements should be in place to prevent wastes from radioactive procedures from being mixed with nonradioactive chemical wastes. Labeling systems should be established to clearly identify the correct disposal locations for various wastes. Waste segregation by the original generator is essential to ensure that waste streams are separate and not pooled unnecessarily in nonspecific categories such as “organic solvents” or “unknowns” (Linins et al., 1991).

98 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES Labels should list the specific names of all hazardous chemical constituents, radionuclides and their concentrations. Effective screening systems must be established to detect radioactively contaminated waste solvents before they are consolidated with larger volumes of hazardous waste. 7.2.2.4.11 Waste segregation: Hazardous/nonhazardous wastes. Segregate hazardous and nonhazardous LSC vials. Keep waste vials containing chemically hazardous LSC fluids separate from those containing nonhazardous cocktails. The nonhazardous vials may be disposed as LLRW or as a solid waste if deregulated levels of radionuclides are present. 7.2.2.4.12 Waste segregation: Listed/characteristic hazardous wastes. LLMW containing EPA-listed hazardous wastes should be collected separately from LLMW that contain only unlisted, characteristic hazardous wastes. The treatment and disposal options for listed wastes are generally fewer, and all residues from processing listed wastes are considered hazardous unless delisted. Petitions to delist waste are difficult, time consuming, costly to prepare, and have a low probability of success. Development of effective, defensible segregation strategies for listed/characteristic wastes requires expertise on EPA hazardous waste classification systems and waste treatability groups. LLMW examples: • Most wastes containing spent methanol are listed wastes with the hazardous waste identification number F003. Unused methanol is a listed waste with the hazardous waste number U154. Ethanol is not a listed waste, and only regulated as hazardous waste if it is in a high enough concentration to exhibit the ignitability characteristic (D001). • Melphalan, a chemotherapy drug sometimes used in combination with radioiodine tracers, is a listed waste when unused or spilled. Wastes contaminated with melphalan resulting from the use of the drug in chemotherapy are not regulated as hazardous, regardless of concentration. • Chloroform is a listed waste (U044) if discarded unused or spilled. Used chloroform and wastes containing chloroform as a contaminant are unlisted wastes. If the concentration of chloroform in waste is above 6 mg L–1 the waste is regulated as a toxicity characteristic hazardous waste.

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7.2.2.4.13 Waste segregation: Biohazardous/nonbiohazardous wastes LLMHW examples: • Potentially infectious materials such as blood and body fluids, and items that may be regulated as medical waste should be collected separately from radioactive wastes because management requirements and disposal costs are usually different. An education program for users of radioactive materials is critical to prevent unnecessary generation of LLMHW. The program must stress the importance of segregating wastes properly and the serious consequences of carelessly placing radioactive materials in the medical waste stream (Mehte, 1993). • It may be necessary to make arrangements for the management of specimens and wastes from patients that receive diagnostic tests using radioactive materials. Typically, these patients have no radiation safety restrictions [see 10 CFR Part 35.75 (NRC, 1994a; 2002b)], however, they may generate contaminated specimens and wastes. These contaminated materials should be segregated from other medical wastes to minimize the volume of waste that may have to be managed in accordance with requirements for LLMHW. • Radioactive animal carcasses may be subject to different management requirements depending on whether the animal was exposed to infectious agents. Segregate potentially infectious animal carcasses and tissues from noninfectious carcasses. Few options exist for disposal of potentially infectious carcasses and tissues. Generally, these will have to be incinerated on-site, or treated to inactivate pathogens before they will be acceptable at off-site incineration facilities. 7.2.2.4.14 Waste segregation: Resource Conservation and Recovery Act regulated/nonregulated low-level mixed waste. Many institutions generate radioactive wastes that contain hazardous chemicals which are not currently regulated as hazardous wastes under RCRA (1976) or state regulations. These non-RCRA LLMW may require management strategies that differ from those applicable to LLRW and RCRA regulated LLMW. Regardless of their regulatory status, wastes containing hazardous chemicals must be managed prudently to protect the environment, comply with other

100 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES regulatory systems and reduce potential future liability. RCRA regulated LLMW should be collected separately from nonregulated LLMW and LLRW for the following reasons: • Chemicals that are not regulated as hazardous waste under RCRA may be regulated under the Clean Water Act (CWA, 1972) and other state and local laws that restrict disposal. Operators of publicly operated treatment works may prohibit or severely restrict the discharge of wastewater containing chemicals listed in CWA to the sanitary sewerage. Commingling of wastes containing these restricted chemicals with LLRW wastewater may result in the loss of an important disposal option for wastes that could otherwise be discharged to the sanitary sewerage. • Because LLMW containing only non-RCRA chemicals are not regulated as hazardous waste there may be no restrictions on storage time and the generator may have a wider variety of management and disposal options. Mixtures of RCRA regulated and nonregulated LLMW must be managed as regulated wastes. Commingling of regulated and nonregulated LLMW increases the amount of waste that may be subject to RCRA management requirements. • There may be other restrictions placed on the generator depending on how these nonregulated wastes are disposed. LLRW disposal facilities may not accept certain nonregulated chemicals unless they have been treated or stabilized. 7.2.2.4.15 Waste segregation: Treatability groups. Segregation groups should be established to prevent commingling of wastes that must be treated and disposed by different processes, and to prevent wastes that have no disposal options from being mixed with wastes that are disposable or can be decontaminated. LLRW examples: • Separate recyclable wastes from wastes that must be disposed; • Collect wastes that can be incinerated separately from those that must be landfilled after storage for decay of the radioactive materials in the waste; • Wastes should be properly sorted to remove those materials that should be compacted for storage or land disposal from those that are to be incinerated. This should result in higher

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overall volume reductions and eliminates costs for compacting waste that will be incinerated. Incineration facilities may not accept compacted waste; Acceptance criteria for incineration may require that the makeup of the combustible waste stream be modified by removing materials that have significant amounts of PVC plastics or other materials made from halogenated organic compounds. This is required to reduce the generation of toxic off-gases and prevent secondary LLMW generation. Certain radionuclides, such as 36Cl, may not be accepted at licensed disposal facilities and have no other current disposal options. Wastes with restricted radionuclides, should be collected and kept such as 36Cl, separately from others. Collect wastes with high activity concentrations separately from routine, lower activity wastes. High activity wastes such as source vials may be difficult to dispose, but are usually generated in small volumes which require minimal storage space until disposal options become available. Segregate equipment that is radiologically contaminated but still useful for future use in radiation areas. By doing this, wastes associated with decontamination or disposal of contaminated equipment are avoided. The savings realized involve not only the avoidance of LLRW, but also reduced investments for replacement equipment.

LLMW examples: Linins et al. (1991) stressed the importance of educating researchers on not combining different waste chemicals. Institutions should make certain that the guidance to investigators clearly establishes what chemicals can be mixed together to avoid creation of certain combinations which are more difficult to treat. The following are examples: • Collect aqueous LLMW separately from non-aqueous solvents. Aqueous wastes may be easily treatable with industrial wastewater technologies such as activated carbon filtration or ultraviolet peroxidation. Solvents and other wastes with high concentrations of organic compounds are usually not suitable for management by wastewater treatment methods. Such wastes may be incinerated or shipped to fuel recovery facilities.

102 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES • Collect wastes that contain chemicals that are difficult to treat from other waste streams. For example, wastes containing organometallic mercury or arsenic compounds may not be treatable and require long-term storage. These should not be combined with other LLMW. • Collect wastes containing toxic heavy metals separately from organic wastes. Generally, the treatment requirements differ significantly. • Collect wastes in accordance with the requirements of the treatment facility that will be receiving the wastes. Additional segregation categories may be required to meet waste stream specific constituent limits. • Keep waste vials containing hazardous LSC wastes separate from those containing nonhazardous fluids. Nonhazardous vials may be disposed as radioactive waste. • Establish strict segregation systems to ensure that lead shielding and other items that contain toxic heavy metals are not disposed with wastes that are to be incinerated or land disposed. Lead and cadmium are used in a wide variety of plastics and other common articles (EPA, 1992b). Because heavy metals are concentrated in the ash by the incineration process, small quantities of shielding and other items containing heavy metals may contaminate large amounts of ash, requiring it to be managed as LLMW. Some institutions x ray solid LLRW for the presence of lead and other nonburnable items (Ring et al., 1993). 7.2.2.5 Material Handling Improvements 7.2.2.5.1 Contamination control. Controlling the spread of contamination is one of the easiest and most effective waste minimization techniques. Contamination control programs should observe the following principles for all categories of waste: • Avoid the contamination of disposable lab items and materials. It may be more prudent to convert to items that can be laundered or readily decontaminated to avoid waste generation. • Avoid the generation of waste by converting from disposable to reusable wipes and towels which can be laundered either on-site or in commercial facilities. Similar success has been achieved by converting from disposable paper protective clothing to launderable cloth protective clothing. In both

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cases, the avoidance of the associated waste was coupled to the improved performance of the cloth substitutes. Savings in the waste program can easily offset costs associated with the laundry operation and monitoring. For all equipment and materials involved in work with unsealed radioactive material, every effort should be made to use materials or equipment that may be readily decontaminated to avoid the need to ever treat such materials as LLRW. Porous materials, woods, and materials and equipment with rough textured surfaces should be avoided if possible. When porous materials or when equipment with intricate detail that would make decontamination difficult must be used, efforts should be made to wrap or seal the material or equipment to facilitate later decontamination, should it become necessary. Peelable spray wraps as well as conventional wrapping material should be considered. Obviously, great gains can be realized in LLRW avoidance if the materials or equipment can be decontaminated. Avoid the spread of contamination. Avoid potential contamination by restricting contact with radioactive material. Avoid sharing laboratories and equipment between radioactive and nonradioactive materials use. Educational and research facilities often find it advantageous to restrict lab areas where unsealed radionuclides are used as much as practicable. Allow only those individuals directly involved with radioactive material use to work in controlled areas. Avoid bringing any unnecessary materials into controlled areas to avoid the creation of unnecessary contaminated waste. This might include books or personal items of lab personnel, packaging material for new equipment or supplies (unpack outside), equipment, or supplies for preliminary steps in the process before radionuclides are introduced (perform elsewhere). Avoid the sharing of lab equipment between projects that use radioactive materials and those that do not. Equip facilities to avoid the potential for contamination of personnel and materials that are unnecessary to the radioactive materials work.

The use of tray systems in place of single use coverings offers other advantages in addition to reduction of waste. Since the work area in trays is usually smaller than that of covered hood work areas and bench tops, there is a natural tendency not to place

104 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES too much on the plastic surface and to restrict storage on the tray to items that contain or are contaminated with radioactive materials. With larger covered spaces, the number of unnecessary items stored in the available space is larger and the potential for contamination of nonradioactive items tends to increase. Another secondary advantage is that the plastic tray can be made of materials that are easily incinerated allowing for good volume reduction. LLMW examples: • Use liners over lead containers and shielding to prevent contamination by radioactive materials. A common example is the covering of lead bricks with aluminum foil, plastic wrap, or epoxy paint to avoid the contamination of the lead. • Lead wool blankets become damaged and possibly internally contaminated. The blankets can be repaired using a new outside covering that allows for a longer life. Specific covers have been designed with oversized grommets so that an outer covering may be easily attached or removed. The covering is made of incinerable material that is easily wiped clean. Additionally, the covering should protect the lead wool from becoming contaminated, thus reducing the potential of LLMW generation. LLMHW example: Avoid cross contamination of biohazardous wastes and radioactive materials. Mehte (1993) cites a problem common to many research hospitals, that of radioactive materials traveling to other areas of the institution via in-patient nuclear medicine studies. Any number of medical conditions (e.g., patient incontinence, insertion of catheters, collection and processing of clinical specimens) can produce potentially infectious radioactive waste. 7.2.2.5.2 Production scheduling. The sequence and frequency by which activities are conducted may affect the volume, concentration and types of wastes generated. Additional attention to planning and scheduling of activities that use radioactive materials may result in a decrease in waste generation. LLRW example: An institution may be changing out HEPA filters on the exhaust system from a radioactive materials handling area on a prescribed frequency. The filters are managed as LLRW. Evaluation of the system may reveal that the filters are being changed

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out too frequently, perhaps not accounting for periods of nonuse. By replacing the filters only when there is evidence of clogging, e.g., pressure drop, generation of LLRW may be greatly reduced. Similarly, the life of HEPA filters may be significantly lengthened by the use of prefilters that are much smaller and easily managed. LLMW example: Activated carbon drum canisters can be used to remove chloroform from aqueous LLMW and replaced after a conservative volume of waste has been processed throughout the units. The spent carbon may require management as LLMW. Developing a method to detect breakthrough of chloroform allows the carbon to be replaced only when performance begins to deteriorate and before the extractable chloroform concentration in the carbon exceeds the concentration defining a LLMW. Carbon use can be reduced and none of the spent carbon is required to be managed as a LLMW.

7.3 Waste Management Methods After all source reduction techniques have been exhausted, then various waste management techniques can be applied in the implementation of an effective waste minimization program. Recycling, which includes reuse and reclamation, is the first waste management technique that should be applied. This can be followed by various treatment and storage techniques. Finally, if, after applying all these techniques, waste must still be generated, then land disposal is the last resort. 7.3.1

Recycling

Recycling of materials and equipment results in one of the most environmentally desirable waste management techniques since the material is used repeatedly or the base material is recovered for reuse. Recycling activities require energy and may result in the generation of secondary waste streams depending upon the reclamation method used. However, recycling should require less energy and likely produce far less waste than the disposal and replacement of the original materials or equipment. For some types of LLRW, recycling is the only feasible management option. The following factors tend to limit recycling options for the small volume of waste produced by laboratories and other small institutional generators:

106 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES • The potentially high cost of research and development required to establish recycling methods for small waste volumes tends to reduce or eliminate cost effectiveness. Laboratory and medical uses usually require defined, high purity materials. Often it is extremely difficult to purify or regenerate wastes to a condition acceptable for reuse in these demanding applications. • It is often impossible to completely separate and remove all detectable radioactive materials from wastes. Concerns about potential regulatory violations and liability from the release of contaminated materials to recyclers may discourage recycling. • New users of materials that cannot be decontaminated must be licensed to accept radioactive materials. • Markets for recycled laboratory materials are limited or nonexistent, particularly for radioactively contaminated materials. • To facilitate recovery of nonhazardous/nonradioactive components from solid wastes, the wastes have to be separated into numerous categories, maintained free of contamination by incompatible materials, and collected separately. For example, plastic items used by laboratories are made from a wide variety of resins such as polypropylene, polyethylene and PVC. These resins generally cannot be recycled together and even small amounts of contaminants such as paper labels or unacceptable plastics may result in rejection of the materials by the recycler. Identifying these materials, and maintaining separate collection and recycling systems may be burdensome, and difficult to justify if the quantities of materials to be recovered are small.

Recycling methods, however, are becoming increasingly available. These tend to consist of reuse strategies employed on-site for specialized processes, decontamination of items for reuse, and large scale processes conducted at off-site, commercial facilities to reclaim materials or energy from wastes. In some situations, other management approaches can be combined with the recycling methods to achieve the best results. For example, wood products may be replaced with metal or plastics which are more easily decontaminated. This is also a product substitution that provides future recycling benefits. Additionally, the use of metal and certain plastics may allow the materials to be

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recycled into other products after the useful life has expired. The only waste reduction option available for contaminated waste wood is a method such as incineration. Recycling includes the decontamination of materials and equipment for reuse for their original intent and the use of reclaimed material for other purposes. To use these techniques, it is paramount that the generator be knowledgeable of commercially available decontamination and other recycling techniques for the radioactive materials or LLMW that is generated. If the generator uses in-house capabilities, it is important that the cost relative to the use of off-site services be compared and that the cost of secondary waste generated as a result of in-house processing be included in the cost evaluation. There are generally few options for recycling or reclaiming materials from LLMW. This is primarily due to the dual regulations that may not adequately consider other hazards and the dual EPA permitting and NRC licensing requirements. In some cases, LLMW is subject to reduced management requirements if it is shipped to reclamation facilities. A good example is the reclamation of radiologically contaminated lead. This material can be called a scrap metal if it is cleaned (of the radiological contamination) and reclaimed or returned to service for its original intended purpose. Maximum recycling of materials should be a goal for any LLRW management program. In most cases the key is to determine what type of materials are reusable, cleanable or releasable so that the amount of waste is reduced. Once the materials are identified and a process to allow the recycling of the materials has been determined, a substitution needs to be made thus reducing the generation of waste by recycling.

7.3.1.1 Use and Reuse—Returning Waste to Original Process Without Reprocessing. The direct reuse of a surplus or waste item without reprocessing is the most beneficial form of recycling from an environmental protection standpoint. It conserves resources, usually generates the lowest amount of secondary pollutants, and requires the least energy input of any of the waste management options. Reuse of waste items, particularly if within the same institution, may also be exempt from many of the reporting, permitting and other regulatory requirements that apply to wastes which must be reprocessed or shipped off-site for recycling, treatment or disposal.

108 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES LLRW examples:

• Redistribute excess, unused radionuclides (e.g., source vials) by the establishment of a system in the institution to find other users. • Return where possible, excess, unused radioactive materials to the supplier. • Laboratory ware and equipment that cannot be readily decontaminated may be useful in its contaminated state for later work with radioactive materials. It may be productive to stockpile and inventory such contaminated equipment for later segregated use, carefully managing it to avoid spread of contamination or loss of control. • Unused equipment that is no longer needed can often be transferred to other facilities for beneficial use. For example, DOE had a small research nuclear reactor at its Hanford site that was unused and destined for disposal as radioactive waste. Instead, the reactor was provided to a Texas university for their nuclear research program, avoiding 25 m3 of waste and saving $116,000 in disposal costs (Kirkendall and Engel, 1994).

LLMW examples:

• Wherever possible, lead containers and shielding should be reused or returned to the supplier rather than recycled at reclamation facilities (smelters). In some situations, lead shielding can be reused even if it is contaminated. • Reuse electrophoresis gel fixing/rinsing solutions (DOE, 1995a). • Phosphorus-32 labeled probes used in northern and southern blotting procedures are commonly discarded after a single application. It has been shown that it is possible to reuse such probes many times, even after storage for multiple half-lives. Reuse can reduce the amount of waste generated to less than 2.5 percent of the amount that would be generated by discarding probes after each use (Winterbourne, 1994).

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7.3.1.2 Use and Reuse—Use of Waste as Raw Material Substitute for a Different Process Without Alteration or Separation LLMW examples: • Acidic or alkaline wastes can sometimes replace neutralization chemicals purchased for use in corrosive LLMW treatment units. This use of wastes to treat waste may greatly reduce the volume of liquid LLRW that would be generated as neutralization products if the acidic and alkaline wastes were neutralized separately with nonwaste chemicals. Procurement costs for raw materials used for treatment are also reduced or eliminated. • Many liquid biomedical LLMW streams are not suitable for direct use at fuel recovery facilities because they have a low specific heat content and contain water and other contaminants at concentrations that exceed limits for fuel. Alcohols or other suitable fuel substitutes must be purchased and blended with the waste to improve combustion characteristics and raise the heat content of the blend to a level acceptable for processing. Waste LSC fluids containing toluene, xylene, pseudocumene or other organic solvents have a high heat content and may be used as replacements for the alcohol in fuel blending operations. 7.3.1.3 Reclamation—Return of Materials to Original Use After Regeneration LLRW examples: • Containers used for the collection of radioactive waste should be of a design that allows them to be emptied, decontaminated and returned to users. In some cases, it may even be acceptable to return contaminated containers to users, provided that the level of contamination is indicated on the container and the contaminant will be compatible with the next waste to be placed in the container. • Tritium gas is becoming scarce and expensive, providing increased justification for recovering the significant volumes of the gas that are lost in the synthesis of tritiated compounds. Tritium can be absorbed and collected on depleted uranium and reused. A benefit of this process is that the gas is partially purified by the process. Industrial

110 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES tritiation manifold systems have been developed for this purpose (Rapkin et al., 1995). LLMW example: Toluene and dioxane can be recovered from spent, solvent-based liquid scintillation cocktails by distillation and purified by additional refining steps which provide complete removal of radionuclides. The recovered solvents can be reused for preparation of new cocktails (Mangravite et al., 1983; Miyatake and Saito, 1984). 7.3.1.4 Reclamation—Processing to Recover Usable Components or Energy (Fuel Blending) LLRW examples: • Radioactive wastes are being investigated as a potential source of medical radionuclides (DOE, 1994b). • Radioactively contaminated oils, which are not regulated as LLMW by EPA, can be blended and used as fuels in a limited number of industrial boilers that have been licensed by NRC. • One of the most effective methods of recycling is to remove the radioactive contamination so that the material can be recycled for unrestricted use. This technique is extremely economical when the material is of consistent geometry and composition to allow for the use of mechanized decontamination and survey methods. • Contaminated ferrous metals that cannot be decontaminated can be reclaimed by making customized shields or storage containers for radioactive materials at a metal melt facility. Custom shielding blocks are being produced from contaminated scrap metal that was previously either stored or disposed of as LLRW. • Some tritium wastes (e.g., tritiated water) of high activity may be subjected to concentration and reutilization (Okada and Momoshima, 1993). Recovery of tritium from low activity wastes is feasible by oxidizing tritium compounds to tritiated water and separating out the tritium by cryogenic distillation (Woodall, 1996).7 7

Woodall, S. (1996). “Cryogenic distillation of hydrogen isotopes,” presented at the Symposium on Mixed Waste Treatment and Disposal. International Isotope Society, October 24, Mystic, Connecticut.

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LLMW examples: • The feasibility of washing and reusing empty glass liquid scintillation vials has been evaluated. The process was found to be technically feasible and cost effective. This vial recycling program was implemented for research groups at a major medical center (McElroy et al., 1982). • Decontaminated lead must be reclaimed by smelting, an EPA mandatory method for this waste stream. • Scrap metals may have the hazardous waste characteristic of toxicity when lead, cadmium or chromate containing paints or anticorrosive coatings have been applied. Such metals may be exempt from most of the hazardous waste management regulations if processed at a bona fide metals reclamation facility. Metals with toxicity characteristic coating can be cleaned using a variety of decontamination methods or melted to produce a shield block or other radioactive product. It is important to note that the secondary wastes produced from these decontamination processes should contain both hazardous and LLRW making the secondary waste a LLMW. • Decontaminated mercury can be recovered by retorting processes, an EPA mandatory method for this waste stream. • RCRA (1976) allows LSC fluids and other ignitable organic LLMW to be blended and used as fuel substitutes in industrial boilers. If the LSC fluid contains only deregulated concentrations of 14C and 3H, it can be sent to industrial boilers without regard for the radioactivity contained and the boiler does not have to be licensed by NRC. Some boilers may accept small quantities of other radionuclides contained in LSC fluids and other combustible LLMW. A very limited number of boilers and industrial furnaces have been licensed by NRC and permitted by EPA for these thermal destruction processes. For many LLMW streams, fuel recovery facilities are currently the only available disposal option. Generators intending to use this option should give careful consideration to the maximum concentrations of radioactive materials and chemical constituents listed in the acceptance requirements of the receiving facility. Institutional waste collection, consolidation, and quality assurance procedures must be in place to ensure that these stringent requirements will be met. Wastes with excessive levels of restricted constituents may not be accepted, or

112 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES require costly blending or pretreatment procedures before they can be accepted. 7.3.2

Treatment for Storage or Disposal

After source reduction and recycling techniques have been applied to the fullest extent feasible, wastes should then be treated to reduce the hazardous properties, volume, and mobility for storage, transportation or disposal. Treatment procedures may also be required to decontaminate, regenerate or recover materials for recycling. The objectives of treatment for various waste classifications are summarized below: • LLRW—minimize radiotoxicity, volume and mobility. • LLMW—minimize chemical hazards, radiotoxicity, volume and mobility. Treatment to separate hazardous chemical constituents and radioactive materials may be necessary. • LLMHW—inactivate pathogens, destroy other characteristics of regulated medical wastes, reduce radio- and chemical toxicity, volume and mobility. For LLMW and multihazard wastes, a primary objective of treatment is usually to eliminate one or more hazardous properties, allowing the waste to be further treated or disposed as a single waste type. For example, LLMW may be treated to remove the chemical toxicity, allowing the waste to be managed as LLRW.

7.3.2.1 Hazard Reduction Methods 7.3.2.1.1 Radiotoxicity reduction: Decay of short-lived radionuclides. Advantage can be taken of the fact that certain radionuclides have half-lives sufficiently short to enable them to be held until they decay to less than detectable levels. Storage for decay can be used to convert LLRW to normal trash, or LLMW and LLMHW to nonradioactive hazardous waste or regulated medical waste. If stored for decay for a period of at least 10 half-lives, waste containing only short-lived radionuclides can then be monitored and a decision made as to whether it can be released as nonradioactive waste. NRC licensees may request authorization to hold wastes with half-lives in excess of 65 d for decay-in-storage. To date, NRC has considered the maximum practical half-life for decay-in-storage to

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be less than 120 d since 10 half-lives would be more than 3 y. However, if adequate storage space, secure containers, and proper oversight can be demonstrated, then decay-in-storage could be allowed for radioactive materials with longer half lives. In this case, the generator could specify the maximum half-life requested for decay-in-storage, and provide justification of need and capability of storage for 10 half-lives in obtaining the applicable regulatory approval. For some institutions, decay-in-storage is the primary means of managing LLRW. A study of generation at one large university-hospital complex found that 68 percent of the total waste volume could be decayed in storage (Emery et al., 1992). There are very limited on-site treatment options for many LLMW streams. This is because few commercial facilities are available, acceptance criteria are difficult to meet, and treatment costs may be prohibitive. Decay-in-storage thus provides a particularly important method for small generators to manage many LLMW forms and reduce potential off-site management costs. Even if the LLMW contains other radionuclides with long half-lives that cannot be decayed in storage, it is often advantageous to decay the short-lived radionuclides. The resulting lower activity waste may then meet acceptance criteria of the commercial facility or be subject to significantly lower treatment costs, which are often based on the specific activity of the waste. LLRW example: Decay-in-storage is routinely used at most facilities for numerous LLRW containing short-lived radionuclides. LLMW examples: • Buffers, fixing and rinsing solutions from gel electrophoresis often contain short-lived radionuclides such as 32P (half-life 14 d) and various aqueous mixtures of acetic acid, methanol, and TCA. These LLMWs can be held for decay-in-storage for 140 d, monitored, and released as nonradioactive hazardous waste for incineration. • Scintillation vials containing only short-lived radionuclides, or short-lived radionuclides and 14C or 3H at deregulated concentrations, may be stored for decay such that they can be managed as nonradioactive waste. In most cases, such waste can be shipped to hazardous waste incineration or fuel blending facilities for treatment or heat recovery. Careful segregation is necessary to be sure only short-lived

114 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES nuclides are present or if longer-lived 14C or 3H are present for dual labeling purposes, the quantity of 3H or 14C is below the limits defining deregulated LLRW. • Occasionally lead shielding may become contaminated with short-lived radionuclides. Storage for decay is preferable to decontamination which usually results in generation of secondary LLMW from the decontamination process. LLMHW example: Because most of the radionuclides used in patient diagnosis and therapy are short lived, decay-in-storage is routinely used for the accompanying wastes. After decay the waste may be managed as regulated medical waste. A less common, but often feasible practice is to inactivate the biohazardous agent(s) in the waste before decay-in-storage. Decay-in-storage may provide other benefits. Most of the pathogens commonly encountered in radioactive medical waste are short lived under the environmental conditions typical of waste storage facilities. By the time the 10 half-life storage minimum is reached most biohazardous agents may be inactivated. Animal carcasses containing short-lived radionuclides can be stored (frozen for example) for decay, then disposed in a manner appropriate for nonradioactive animal wastes. When only very short-lived radionuclides are used in conjunction with biohazardous material, it may be practical to hold waste in the restricted area until the radioactivity has decayed, then process it in the normal manner for the biohazardous component. While most of the radionuclides used for medical procedures are short lived, there are important medical uses for longer-lived radionuclides (Nagle, 1994) which may generate wastes that are impractical to decay-in-storage. 7.3.2.1.2 Radiological hazard reduction: Decontamination LLRW example: Many living and dead organisms accumulate heavy metals and radionuclides. The controlled use of this phenomenon has lead to the development of biotechnology methods for removing heavy metals and radionuclides from dilute aqueous process effluents (Ashley and Roach, 1990; Macaskie et al., 1994). LLMW examples: • Lead contaminated with radioactive materials can be decontaminated using mildly aggressive mechanical decontamination techniques and is easily decontaminated using a

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variety of chemicals. One of the best ways to decontaminate lead with thin superficial layers of contamination is to remove the contamination with an abrasive medium under pressure. A mixture of alumina with water and air rapidly and effectively decontaminated lead (Lussiez, 1993). The secondary wastes from lead decontamination are radioactive and usually meet the definition of toxicity characteristic hazardous waste in 40 CFR Part 261 (EPA, 1980a). The secondary LLMW require additional stabilization and solidification steps to reduce the leachability of lead to acceptable levels before it can be disposed as LLRW. • Absorption and extraction methods may be applied to extract radioactive materials from LLMW. However, experiments by Linins et al. (1991) on LLMW streams from biomedical research demonstrated that large amounts of adsorbent materials were required to remove even small amounts of radioactivity. Liquid:liquid extractions with water saturated SDS and ethanol reduced activity concentrations up to 10-fold but could not reach background. • Radioactive nucleotides can be removed from large volumes of buffer solutions by passing the waste though a chromatographic column filled with a strong anionic exchange resin (Kaczorowski et al., 1994). • Distillation and refining procedures have been developed that can remove radioactive contaminants from spent LSC cocktails prior to disposal (Miyatake and Saito, 1984). 7.3.2.1.3 Chemical hazard reduction. Commercial facilities for treatment and disposal of LLMW are limited, and options for many waste streams are nonexistent. As elaborated by Linins et al. (1991), in the absence of disposal outlets, there are only two general alternatives: eliminate LLMW generation by source reduction methods, which is often impractical; or separate the radioactive contaminants from the hazardous chemicals so that they may be disposed separately. Separation of constituents to facilitate disposal remains a major objective of treatment procedures for LLMW. In most cases, radioactive wastes containing hazardous substances must be treated to reduce or eliminate chemical toxicity and other hazardous properties such as ignitability, corrosivity or reactivity before disposal. For EPA regulated LLMW, generators are required to minimize toxicity to the extent feasible, and the specific methods that must be used to reduce toxicity or other hazards may be prescribed by regulations. Required treatment methods for

116 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES regulated wastes that are subject to LDR may be found in 40 CFR Part 268 (EPA, 2001d). In some cases, treatment is also required to stabilize the waste in a form acceptable for shipment to off-site TSD facilities. Examples of such wastes are wastes that are highly reactive, potentially explosive, thermally unstable, or tend to pressurize containers may be considered forbidden materials under DOT regulations. Treatment procedures for LLMW can be complex, involving multiple separation and treatment steps to remove hazardous characteristics and comply with approved treatment standards for disposal. Treatment is applied to the hazardous constituents of LLMW to minimize chemical toxicity or remove other hazardous characteristics associated with the chemical composition of the waste such as ignitability, corrosivity and reactivity. Generally, unlisted wastes with hazardous characteristics may be treated and then managed as LLRW if the hazardous characteristics have been removed. The treated waste is now easier to handle, store and process for final disposition. Residues from treatment of EPA-listed wastes must still be considered LLMW, even if the hazardous characteristics have been removed. On-site treatment is the only option for LLMW that cannot be treated at off-site facilities (Linins et al., 1991). Before attempting to treat LLMW that meets EPA or state definitions of hazardous waste, institutions should always determine if the activity is subject to permitting requirements. A RCRA Part B permit is usually necessary except for elementary neutralization units, and treatment processes that can be performed within the waste containers. The application process for a RCRA permit is difficult, time consuming, and costly and should only be undertaken if sufficient quantities of waste are generated to make treatment cost effective, or there are no alternatives to on-site treatment methods that require permits. LLRW examples: • Elementary neutralization of corrosivity characteristic LLMW is probably the most widely practiced treatment process for aqueous LLMW. Conceptually, the process is simple, consisting of adjusting the pH of the waste with a suitable acid or base, as appropriate, to a nonhazardous pH range. This removes the corrosivity characteristic resulting in a nonhazardous radioactive waste, provided that the waste has no other hazardous characteristics such as toxicity. In

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many institutions, both acidic and basic wastes are generated, which can be used to neutralize each other, minimizing volumes and reducing costs of procuring neutralization agents. Neutralization reactions, which are usually exothermic, should be carried out with precautions to control heat, the speed of the reaction and emissions of hazardous gases, and radioactive aerosols. Neutralization agents should be selected which will not generate gaseous reaction products nor displace radioactive materials from solution. Planning is important so that the resulting neutralized LLRW is compatible with the secondary processes required for final disposal or reuse. • Small scale detoxification and inactivation methods have been published for numerous laboratory chemicals (Armour, 1991; Lunn and Sansone, 1994; Pitt and Pitt, 1985). Many of these methods can be applied to LLMW, carried out on-site in containers and therefore may be exempt from EPA permitting requirements. These methods may be particularly advantageous for laboratories and other small generators that have small waste streams for which there are no off-site treatment facilities available. A disadvantage of many of these methods is that they frequently require the use of strong oxidizing agents such as potassium permanganate, and they are time consuming and expensive due to high reagent-to-waste ratios (Linins et al., 1991). A limited number of larger scale chemical treatment methods have been developed and permitted, or are under development (Kirner et al., 1991; 1995; DOE, 1995b). These may be appropriate for use by larger institutional generators for treatment of LLMW or aqueous LLRW streams that are not regulated as hazardous waste, but contain toxic pollutants. Some of these methods are described in the following sections.

7.3.2.1.4 Chemical hazard reduction: Bioremediation. Bioremediation methods are now widely used to clean up sites contaminated with hazardous and LLMW. These methods can probably be scaled down and adapted to treat a variety of organic wastes streams generated by small institutional generators. Bioprocessing methods are attractive because they can be carried out on a small scale with minimal equipment.

118 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES LLRW example: Conventional industrial wastewater biotreatment processes can probably be used to treat liquid radioactive wastes. Bioprocessing methods are being investigated for treatment of trace levels of priority pollutants in radioactive wastewater from biomedical research facilities. LLMW examples: • Biological treatment methods have been developed and patented for degradation of toluene and xylene based liquid scintillation cocktails (Wolfram and Rogers, 1989a; 1989b). The treated waste is no longer ignitable and can be managed as LLRW. Biotreatment processes for other LLMW has been developed (Wolfram et al., 1997). • Microorganisms can be used to remove toxic heavy metals from liquid industrial wastes (Macaskie and Dean, 1989). Investigations have shown that Citrobacter sp. can be used to remove uranium and transuranic elements, plutonium, and americium from various radioactive wastes (Macaskie et al., 1994; Tolley and Macaskie, 1993). Fixed enzyme reactors or organisms with enhanced reducing capacity may be used for the bioremediation of uranium-contaminated wastes and waste streams (Lovley and Phillips, 1992; Lovley et al., 1993).

7.3.2.1.5 Chemical hazard reduction: Granular activated carbon filtration LLRW example: Radioactive wastewater that does not contain chemicals regulated by EPA as hazardous waste may still contain trace levels of toxic organic chemicals such as naphthalene, chloroform and phthalate compounds that must be treated before disposal to comply with CWA (1972) and other applicable regulations. Granular activated carbon (GAC) filtration is an example of a method that has been successfully used to remove trace levels of toxic organics from large volumes of radioactive wastewater (Rau, 1993).8

8

Rau, E.H. (1993). “Preliminary results of activated carbon adsorption,” presented at the National Low-Level Waste Management Program Biomedical Mixed Waste Workshop, August 4-5, Bethesda, Maryland.

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LLMW example: GAC is used to treat high volume aqueous LLMW contaminated with low concentrations of chloroform, or other toxic organic compounds that exhibit low solubility in aqueous solutions (DOE, 1995b; Rau, 1993).8 Treatment of chloroform toxicity characteristic wastes yields a filtrate that can be managed as liquid LLRW. The major disadvantage of the method is that GAC has a limited capacity to absorb organic compounds. A major disadvantage of this method is due to problems associated with management of spent carbon. At a minimum, the spent carbon must be managed as LLRW. It must be managed as LLMW if it was used to treat EPA-listed wastes, or if toxicity characteristic leaching procedure (TCLP) extracts from the carbon exhibit a RCRA (1976) waste hazardous waste characteristic such as chloroform toxicity. No commercial facilities in the United States currently accept radioactive spent GAC for regeneration, and disposal options remain limited (DOE, 1995b; Rau, 1993).9

7.3.2.1.6 Chemical hazard reduction: Oxidation methods. A wide variety of chemical oxidation methods are in use or under development to oxidize hazardous organic compounds in LLRW and LLMW.

LLMW examples: • The Los Alamos National Laboratory is developing technologies that are capable of destroying hazardous organic compounds in wastes, converting them to water and carbon dioxide (Austin, 1991). • Molten salt destruction processes are being developed for oxidation of LLMW (Haas et al., 1994; Upadhye et al., 1993) and radioactive hydraulic oil wastes (Darnell et al., 1993). • Molten metal technology is now commercially available for treatment of contaminated metals and a wide variety of LLRW and LLMW. Wastes are immersed in a molten metal bath which acts as a catalyst and solvent in the dissociation of the feed and in the synthesis of products. The process has several potential minimization benefits in addition to 9

Rau, E.H. (1993). “Results of ultraviolet peroxidation studies,” presented at the National Low-Level Waste Management Program Biomedical Mixed Waste Workshop, August 4-5, Bethesda, Maryland.

120 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES destruction of hazardous chemical compounds in the waste (Herbst et al., 1994; 1995):10 - Processing of contaminated scrap metals results in metal decontamination in excess of 99 percent; - Waste volume is reduced; - Potential formation of one or more decontaminated product streams such as fuel gases, ceramics and metal alloys; and - Radionuclides incorporated into high temperature glass compositions are stabilized in a durable, nonleachable form suitable for final disposal. • Laboratory scale catalyzed thermal oxidation systems have been developed and operated successfully (Birdsell and Willms, 1995; Weaner, 1996).11 • Aqueous LLRW containing low concentrations of organic compounds can be treated using Fenton’s reaction, an oxidation process conducted with hydrogen peroxide in the presence of a catalyst, usually ferrous sulfate.

7.3.2.1.7 Chemical hazard reduction: Ultraviolet peroxidation. Ultraviolet peroxidation is an oxidation process originally developed for treatment of low concentrations of toxic organic compounds in wastewater. In this process hydrogen peroxide is added to the wastewater which is then passed by a high intensity ultraviolet light source. The ultraviolet light activates organic molecules, making them more amenable to oxidation, and converts some of the hydrogen peroxide into hydroxyl radicals. Hydroxyl radicals are highly reactive and act upon the organic compounds present in the wastewater. Carried to completion, the oxidation reaction produces carbon dioxide, water, and inorganic ions. LLMW example: Commercially available ultraviolet peroxidation systems have been adapted to successfully treat aqueous LLMW streams from biomedical research laboratories (DOE, 1995b; Rau, 10

Herbst, C.A., Loewen, E.P., Protopapas, C.A., Chanenchuk, C.A. and Wong, E.W. (1995). “QUANTUM-CEP (tm) applications to mixed and radioactive wastes,” presented at Waste Management 95, University of Arizona. 11 Weaner, L. (1996). “Laboratory scale oxidation of mixed waste,” presented at the Symposium on Mixed Waste Treatment and Disposal. International Isotope Society, October 24, Mystic, Connecticut.

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1993;12 1997). The method can be used to treat a wide variety of organic compounds; however, it is limited to aqueous waste streams that are not highly colored or turbid, and meet other chemical criteria for processing. 7.3.2.1.8 Chemical hazard reduction: Steam reforming. Steam reforming is under development as a process to treat organic hazardous wastes and to regenerate or decontaminate activated carbon. In this process the waste is held in an enclosed vessel under conditions of high temperature and pressure. Hydrolytic reactions take place, converting organic compounds to carbon monoxide, carbon dioxide, hydrogen, methane, and water. An advantage of the process is that it can be used to treat solid LLMW forms such as activated carbon that cannot be treated at the currently available commercial facilities that accept only liquid wastes. The process is reportedly applicable to a variety of biological wastes and organic compounds. 7.3.2.1.9 Biohazards and medical waste characteristics. Transmission of HIV and other infectious diseases from medical wastes through environmental media to the general population has not been documented and does not represent a significant hazard (Sattar and Springthorpe, 1991). The primary hazard is to workers that are occupationally exposed to wastes, particularly through contaminated needles and other injection injuries resulting from direct handling of infectious wastes. The primary objective of treating biohazardous radioactive wastes is to render any potentially infectious organisms (pathogens) that may be present incapable of causing disease. Treatment may consist of various inactivation, disinfection or sterilization methods. Inactivation refers to a process that renders organisms noninfectious. Disinfection processes reduce the number of organisms below a level which is not infectious to a healthy adult. Sterilization is a process by which all living organisms in a waste are killed, regardless of their potential to cause disease. For waste management purposes, there may be additional or secondary treatment objectives, for rendering the waste incapable of causing disease. These include:

12

Rau, E.H. (1993). “Results of ultraviolet peroxidation studies,” presented at the National Low-Level Waste Management Program Biomedical Mixed Waste Workshop, August 4-5, Bethesda, Maryland.

122 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES • Preservation to prevent growth of microorganisms, putrefaction, and gas generation; • Destruction of needles, syringes and other sharp objects; and • Incineration or mechanical processing to remove other characteristics which cause the waste to be regulated as medical waste or unacceptable for disposal in LLRW facilities. Few, if any, commercial medical waste incineration facilities accept radioactive wastes, and allowable concentrations of 3H and 14C, which may be released during the incineration process, are very low. Most incinerators that are licensed to accept LLRW are captive facilities located on hospital or educational institutions. Many of these incinerators are being closed because of difficulties in meeting the increasingly stringent air pollution control standards that are now being applied to medical waste incineration. Other technologies, including plasma arc pyrolysis and microwave radiation are becoming available as alternatives to incineration, however, commercial facilities that employ these methods do not currently accept radioactive wastes. 7.3.2.1.10 Biohazard reduction: Inactivation of pathogens. Most of the potentially infectious radioactive wastes that are routinely generated by biomedical facilities and hospitals consist of liquid specimens and solid wastes contaminated with blood and body fluids. Solid tissues, and potentially infectious animal carcasses are usually small fractions of the total biohazardous waste stream. Cultures of cells and microorganisms that may be highly infectious are generally inactivated in the laboratory and not commonly encountered as radioactive wastes. The agents of most contemporary concern in medical wastes are the hepatitis viruses, especially hepatitis-B and -C viruses; HIV, which causes the acquired immunodeficiency disease; Mycobacterium tuberculosis, the tuberculosis bacterium; and other mycobacteria. Most of the potentially infectious organisms that are routinely present in medical wastes can be readily inactivated by thermal and chemical methods, provided there is appropriate penetration of the inactivating agent into the waste and adequate contact time. The presence of radionuclides or hazardous chemicals in the waste complicates the selection of inactivation methods, and the order in which the methods must be employed.

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It should be understood that while inactivation of potentially infectious agents in wastes may be sufficient to render the waste safe for handling as LLRW, the inactivation may not be sufficient treatment for long-term storage or acceptance by LLRW management facilities. Preservation and destruction of other characteristics that cause waste to be regulated as medical waste may be required. 7.3.2.1.11 Biohazard reduction: Chemical disinfection. Liquid chemical disinfectants such as bleach (sodium hypochlorite solutions), iodophors, quaternary ammonium, and phenolic compounds are most frequently used to inactivate liquid wastes, and biohazardous contaminants on nonporous materials. Gaseous decontamination methods using formaldehyde or ethylene oxide are also available, but not commonly employed for routine treatment of medical wastes. For LLMHW, the following considerations must be given to selection of disinfectants: • The disinfectant must be effective against the pathogens present in the waste. Sattar and Springthorpe (1991) reviewed the survival and disinfectant activation of HIV and found that the effectiveness of some chemical disinfectants may be overstated. Alcohol, the most commonly used disinfectant, was found to be ineffective for high viral concentrations (Aranda-Anzaldo et al., 1992). • The disinfectant must be chemically compatible with other chemical constituents in the waste. Use of incompatible disinfectants may result in inactivation of the disinfectant, dangerous chemical reactions, formation of toxic reaction products, or the emission of volatile radionuclides or hazardous gases. • Select chemical disinfectants considering the intended final disposition of the waste. The addition of some chemical disinfectants may cause the treated waste to be regulated as a LLMW, or preclude discharge to the sanitary sewerage without additional treatment steps (chemical detoxification). Chloroform and methanol should not be used as growth retardants in containers used to hold aqueous LLRW for decay as was advocated by Party and Gershey (1989). These chemicals are now more restricted and would likely cause the waste to have to be managed as a LLMW.

124 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES • Some disinfectants are corrosive to steel. Select disinfectants that will not degrade waste storage containers. • Use only disinfectants that are registered by EPA for their intended use.

7.3.2.1.12 Biohazard reduction: Steam autoclave sterilization. Steam autoclaves are widely used to sterilize medical wastes, however, the threat of volatilizing the radioactive materials and contaminating the autoclave has discouraged the use of autoclaves for treating LLMHW. Precautions must be taken with volatile radionuclides such as 131I and 35S which may be released when wastes are subjected to the elevated temperatures required for inactivation of pathogens. Effective and verifiable autoclaving techniques have been developed for LLMHW containing certain volatile radionuclides. These techniques reduce the potential for emissions using activated charcoal vent filters and absorbents (Stinson et al., 1990; 1991). As described by Stinson et al. (1990; 1991) a quality assurance program should be established to monitor the effectiveness of the autoclave process. All waste packages should be affixed with sterilization markers to confirm waste was properly autoclaved, and the autoclaves should be periodically tested to ensure effectiveness. Autoclaved wastes can usually be routinely handled as LLRW only. LLRW disposal facilities that are expected to receive autoclaved LLRW should be acquainted with the institution’s marking system to facilitate acceptance. LLMW containing ignitable, reactive or volatile chemicals should not be autoclaved.

7.3.2.1.13 Biohazard reduction: Preservation. Biological degradation processes, primarily associated with the growth and metabolism of microorganisms, occur in a wide variety of wastes, including inorganic materials. Degradation processes occur most rapidly in animal carcasses and other wastes containing biological materials, or organic materials in the presence of water. If not controlled by appropriate preservation methods, these processes may result in the production of odors, acids, gases, and other undesirable metabolic products. These may increase the potential for mobilization of waste constituents, pressurize containers, or degrade components of containment systems. Preservation methods must be employed when it is necessary to store degradable wastes for long periods of time or when they will be disposed in landfills.

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Conditions required for growth of microorganisms include: • an inoculum, or source of microorganisms capable of growing on or metabolizing the waste • water • temperature range within which growth may occur • nutrients • absence of inhibitory chemicals Preservation strategies attempt to remove one or more of the conditions required for growth. Preservation methods most commonly employed include freezing or refrigeration, dehydration, liming, and the addition of chemical disinfectants. LLRW example: Aqueous radioactive wastes collected from biomedical laboratories usually support the rapid growth of microorganisms with production of odors and slimes. An appropriate disinfectant should be added to the collection container to preserve the waste during collection and decay-in-storage. LLMHW examples: • Body fluids collected from patients during limb isolation perfusion treatment of melanomas contain blood, cytotoxic drugs, and 131I. The wastes are held in a freezer for approximately 100 d for decay of the 131I. After decay, the wastes may be treated in a medical waste incinerator. • Addition of quicklime to animal carcasses. 7.3.2.2 Volume or Quantity Reduction Methods 7.3.2.2.1 Minimization. Minimization strategies to reduce the weight or volumes of waste for long-term storage or disposal are usually implemented after all recycling and treatment strategies have been completed. For LLRW, volume reduction techniques are practiced on a voluntary basis to reduce transportation costs, space required for storage and disposal, and in some cases, to reduce disposal costs when disposal fees are based on volume. The key to maximizing volume reduction is to generate a waste in a form that allows for the application of the best available volume reduction technique. All of the volume reduction processes available commercially should be considered to determine which one fits the materials and the radionuclides present, and offers the highest overall cost benefit. The effect of the volume reduction

126 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES method on the ability to store, transport and dispose of the waste must also be considered. It is possible that a particular volume reduction technique could result in higher radiation levels or increase the activity concentration so that the cost for either storage or transport actually increases. Some volume reduction techniques may not be appropriate for the radionuclides present or the waste materials. Waste processors should allow the generator to help determine the most appropriate volume reduction technique. If the waste is generated in a region that is developing a new disposal facility, it is very important that the waste form requirements for the new facility be taken into account prior to applying the volume reduction technique. The disposal sites are trending toward more uniform waste forms that do not have any liquids or other characteristics that may affect the disposal unit from a structural stability standpoint. Common volume reduction techniques are described below. 7.3.2.2.2 Compaction. Compaction is a widely used, versatile and economical method to reduce the volume of solid wastes that do not lend themselves to decontamination, metal recycling, or incineration. Regular compaction units produce low but economical volume reduction ratios. The volume reduction will vary greatly with the input density, the theoretical density, the compaction force, and the potential springback. Volume reduction ratios are commonly in the range of 3:1 to 6:1. Most items can be compacted to achieve some measure of volume reduction. This technology is not very complicated and can be adapted for any size container and a variety of compaction forces. The largest compactors (supercompactors) for processing solid waste can apply about 5,000 tons of pressure on a 55-gallon drum and can compact both drums and boxes. Supercompaction is generally only available as an off-site volume reduction option, while normal compaction can economically be performed on-site at most facilities. Supercompactors have been used at DOE facilities to reduce the volume of LLMW being stored on-site and, comply with RCRA (1976) requirements until off-site storage and disposal sites are approved (Jones, 1992). This may not be a viable option for small institutional generators that are not permitted as storage facilities. Such institutions could ship waste off-site for supercompaction, but would probably be prohibited from receiving it back for storage because under RCRA regulations they are not currently permitted to receive wastes from off-site.

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Hazards posed by the presence of sharps must be considered when developing volume reduction methods for radioactive medical wastes. Under no circumstances should operators be allowed to use their hands for manually compacting waste containers.

7.3.2.2.3 Concentration. Generally, volume reduction methods for liquids include concentration and removal of radionuclides or chemical constituents from a large volume, inert matrix. LLRW examples: • Distillation can be used to separate or concentrate waste fractions and facilitate recovery, treatment or disposal. A disadvantage is that it is often impossible to get complete separation of radioactive materials from the distillate; and may well be managed as LLMW. Other commonly used concentration methods include adsorption on activated carbon or resins and evaporation. • Tritium can be concentrated and stored on beds of depleted uranium pending disposal or recycling. Three grams of uranium can hold more than 37 TBq of tritium (Rapkin et al., 1995). LLMW examples: • A large fraction of the LLMW generated by biomedical research can be separated into nonradioactive chemical waste and radioactive aqueous wastes (Linins et al., 1991). For example, HPLC wastes containing acetonitrile, methanol and water can be separated into fractions that can be disposed. The distillate can be disposed as nonradioactive aqueous chemical waste. The still bottoms, which represents about 40 to 50 percent of the original waste volume, can be discharged to the sanitary sewerage as permitted under 10 CFR Part 20.2005 (Linins et al., 1991; NRC, 1981). • Distillation procedures have been employed to reduce the volumes of spent LSC fluids requiring disposal as radioactive waste. Volatile solvents can be distilled from the fluids for disposal as nonradioactive hazardous waste. Reductions in the volume of radioactive waste, from toluene-based LSF of 45 to 82 percent, have been obtained (Claycamp et al., 1978; Fletcher and Conroy, 1980). Distillation of these fluids

128 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES is not widely practiced today since most modern fluid formulations contain lower concentrations of economically recoverable solvents. Other economic, safety and regulatory considerations do not favor distillation of these wastes. • Linins et al. (1991) have found resins to be highly effective in removing phenol from aqueous LLMW. 7.3.2.2.4 Decontamination of surfaces before disposal. In situations where facilities are to be decontaminated, many contaminated surfaces are removed and disposed using traditional volume reduction processes. In the case of wood or concrete, the contamination may only be on the surface or near the surface. The most effective volume reduction method is to remove the portion of the material that is contaminated. Current disposal costs are such that the expenditure of manpower for such decontamination efforts is often cost effective. Such decontamination efforts may also be effectively used in day-to-day lab operation. LLRW example: When working with radionuclides that are readily detectable with a lab survey meter, much LLRW can be avoided by surveying discarded materials, segregating noncontaminated from measurably contaminated, and attempting decontamination, if practical. Laboratories have greatly reduced their LLRW volumes by washing disposable lab ware, even broken lab ware, before disposal as nonradioactive waste. Laboratories have found it cost-effective to install ultrasonic cleaners to decontaminate pipette tips for normal trash disposal or recycling, even to wash and monitor protective gloves before removal thus diverting them to normal trash disposal. Large pieces of equipment, like freezers or refrigerators can also be monitored for contamination and cleaned if necessary. Swipes should be used to check for low energy beta contamination. 7.3.2.2.5 Other volume reduction techniques for biological wastes. The most effective and widely practiced method of reducing the volume of biological materials, such as animal carcasses, is incineration. In some cases, other treatment methods must be employed due to the unavailability of incineration facilities, the presence of radionuclides that exceed acceptance criteria of the facilities, or high costs associated with incineration. Biological waste volume reduction methods that have been used as alternatives to incineration are described below.

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7.3.2.2.6 Other volume reduction techniques for biological wastes: Drying. The literature describes several methods of reducing the volume of animal carcasses. In Japan, animal waste containing radioactive materials must be decayed in storage at the institution where it is generated. After short-lived radionuclides are decayed, the waste must be dried by means of lyophilization or microwave treatment. Dry distillation has also been investigated and found to offer several advantages including an 8 to 40 percent reduction in volume (Saito et al., 1979; 1995). Freeze-drying of organic materials has been demonstrated to be an effective and economical option for volume reduction. This method can achieve volume reduction ratios in the range of 10:1; however, results vary greatly with the water content of the organic material. An added benefit is that the processed materials can be packaged as a solid for disposal and do not require the additional cost of packaging and disposal of liquids that are currently required at the commercial disposal sites. The deletion of a secondary container and need for absorbent materials reduces the volume by another factor of two resulting in approximately 20:1 volume reduction. A freeze-drying process may be more appropriate for organic materials such as animal carcasses that are not suitable for incineration or compaction. Universities have reduced the amount of animal carcass waste by using an evacuation bell to freeze-dry the animals. The dry solid waste that results from the freeze-drying of animal carcasses can reduce the volume to 28 to 35 percent of the original volume (Hamawy, 1995). Freeze drying can increase the potential release of 3H and 14C which would require monitoring of the off-gas from the process. 7.3.2.2.7 Other volume reduction techniques for biological wastes: Biological reduction. Biological methods, such as dermestid beetles, have also been used to reduce carcass volumes (Party et al., 1995). 7.3.2.2.8 Other volume reduction techniques for biological wastes: Grinding and shredding. Grinding is often used to reduce the volume of medical wastes prior to storage or disposal. Use of this technique for radioactive medical wastes is constrained by several factors. Grinders used for medical wastes containing long-lived radionuclides will become contaminated radiologically and must be dedicated to processing only radioactive wastes. In most institutions such wastes are a relatively small percentage of the overall

130 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES waste generation. Therefore, it may not be cost effective to procure and maintain grinders for processing the waste. Control of biohazardous aerosols and other radioactive or potentially infectious emissions may be difficult. Grinders are also subject to jamming and other mechanical problems that may result in significant downtime and hazards to personnel making repairs. Shredding followed by chemical disinfection has been used to treat medical wastes and equipment designed for this purpose has been used commercially. Problems with dispersion of microbial aerosols during the process have been reported (Jette and Lapierre, 1992) which suggest that emissions of radionuclides could also occur if this process was used to treat LLMHW. 7.3.2.2.9 Other volume reduction techniques for biological wastes: Alkaline hydrolysis. Radioactive tissues and animal carcasses from biomedical research can be treated by an alkaline hydrolysis method to eliminate or reduce the volume of waste that requires disposal as solid LLMHW (Kaye and Weber, 1992). The method involves heating of the wastes in a hermetically sealed digester at slightly elevated pressure with a circulating solution of aqueous sodium hydroxide. Hydrolysis and degradation reactions convert most of the biological materials to a liquid hydrolysate that may meet requirements for disposal into sanitary sewerage. The volume of solids is reduced to approximately three percent of the original carcass weight. This process has also been shown to effectively decontaminate cultures of indicator organisms placed in the wastes (various bacteria and Giardia cysts). 7.3.2.3 Thermal Treatment 7.3.2.3.1 Incineration. Incineration is potentially suitable for a wide variety of radioactive wastes and achieves several minimization objectives including oxidation of toxic or organic compounds, high volume reductions, and, in some cases, encapsulation or vitrification of nonvolatile radionuclides and toxic metals. An important objective of incorporating incineration into a LLRW program is also to destroy the potentially infectious or known infectious nature of the waste, and render the material unrecognizable. The combined use of decay-in-storage and on-site incineration processed approximately 84 percent of the volume of waste generated at one large facility (Emery et al., 1992; Vetter, 1992). The availability of commercial facilities licensed to burn radioactive wastes has been very limited, while new on-site, captive incinerators have been very difficult to permit.

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LLRW example: Combustible materials such as oil, wood, plastic and paper can be reduced in volume considerably by incineration. One company in the United States operates a commercial LLRW incineration unit and achieves an average volume reduction ratio approaching 200:1. This high volume reduction is in part due to the secondary process of compacting the ash to achieve an additional 3:1 volume reduction. During 1993, approximately 21,237.8 m3 or 3,175,146.6 kg of wastes were incinerated. The volume reduction result will vary significantly with the material that is incinerated. LLMW example: A limited number of commercial facilities accept liquid forms of LLMW and radioactive oils for blending and burning as fuels in industrial boilers. LLMHW example: The most widely practiced method of treating biological materials, such as animal carcasses and excreta, is incineration. Incineration achieves the largest volume reduction, destroys pathogens, and other regulated characteristics of medical waste. Some larger institutional generators, such as the National Institute of Environmental Health Sciences (NIEHS), have on-site incinerators for volume reduction of LLRW from biological experiments and find this method to be very beneficial due to land burial restrictions and increasing costs of disposal (Hamrick et al., 1993). Biological materials usually do not have a significant British thermal unit value and must be incinerated with other combustible or supplemental fuel. The most significant problem with some biological wastes is the presence of high concentrations of 14C or 3H. These radionuclides are not retained within the ash (Emery et al., 1992) or easily collected by the off-gas system. The combustion products of incineration, water and carbon dioxide, are ideal transporters for these nuclides. EPA [40 CFR Part 261 (EPA, 1995a)] release limits restrict the amount of radionuclides present in the organic materials that can be released to the environment. Air effluent contamination levels are typically restricted to air effluent concentrations at the point of release. Of the radionuclides most commonly encountered in wastes from biological experiments, only 35S is retained to any measurable extent in ash under the conditions of incineration employed at NIEHS (Hamrick et al., 1986; 1989). Microsphere wastes are sometimes incinerated. The resulting ash is then acceptable for disposal as nonradioactive waste. It may be necessary to hold animal wastes containing other short-lived nuclides for at least partial decay before incineration to

132 / 7. WASTE MINIMIZATION METHODS AND EXAMPLES keep activity concentrations in ash and emissions to an acceptable level. 7.3.2.3.2 Other thermal processes: Plasma arc. Plasma arc processing is a method in which wastes are thermally treated in a chamber which is subjected to extremely high temperatures from an electric arc (plasma torch). In some systems the process is oxidative, carried out in the presence of air. Other systems are operated without oxygen, degrading organic compounds to inorganic materials and gaseous, reduced forms such as hydrogen and methane. The plasma arc treatment systems are becoming commercially available, and being used for treatment of medical wastes at hospitals. They may become an option for treatment of LLRW and LLMW. A laboratory demonstration project has been successfully completed using several different surrogate waste forms that are representative of some common DOE waste streams (Geimer et al., 1993). Plasma arc processing offers several potential minimization benefits: • The process is generally not considered incineration and may not be subject to incinerator permitting requirements. • Off-gases produced may be treated and released, or captured and used as a fuel supplement. • The process can accept a wide variety of wastes and heterogeneous mixtures. Unlike most other technologies, thorough characterization of wastes is not required. This minimizes waste handling, potential exposures, costs, and time associated with characterization. • No pretreatment of wastes is required. • The process destroys organic compounds and stabilizes heavy metals and radionuclides in one step. • Solid residues of the process are vitrified in a glass-like matrix that is durable and has high resistance to leaching. 7.3.2.4 Mobility Reduction Methods. The final treatment steps carried out prior to placing wastes in long-term storage or disposal facilities are to reduce the potential mobility of radioactive and hazardous materials remaining in the waste. These steps are usually completed after the waste has been detoxified and reduced in volume to the maximum extent feasible. LLRW must meet the

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requirements of 10 CFR Part 61 (NRC, 2001) and the specific form requirements of the receiving facility before disposal. EPA has established minimum treatment standards for land disposal of hazardous wastes, which require treatment of the waste such that the remaining toxic or hazardous constituents are in a form that is not likely to leach out and contaminate groundwater under the conditions expected to be encountered in a sanitary landfill. The purpose of some treatment standards is to reduce the mobility, leachability and toxicity of the waste as determined by TCLP, which is defined in 40 CFR Part 261 (EPA, 1980a). Treatment standards for some specific LLMW types may be found in 40 CFR Part 268 (EPA, 2001d). The most common characteristic of TCLP toxicity is the presence of soluble heavy metal compounds. This characteristic can normally be removed by chemically binding or encapsulating the waste in a solidification media. If the resulting solidification media subsequently passes the TCLP testing requirement, the material is no longer considered to exhibit the toxicity characteristic. The solidification method, the process to perform the solidification, and the