Energy and the Environment

First Edition, 2011

ISBN 978-93-81157-43-5

© All rights reserved.

Published by: The English Press 4735/22 Prakashdeep Bldg, Ansari Road, Darya Ganj, Delhi - 110002 Email: [email protected] 

Table of Contents Chapter 1- Introduction to Energy and the Environment Chapter 2 - Environmental Issues with Energy Chapter 3 - Environmental Effects of Biodiesel Chapter 4 - Environmental Impact of Palm Oil Chapter 5 - Environmental Effects of Coal Chapter 6 - Major Effects of Coal Mining on Environment Chapter 7 - Environmental Issues with Petroleum Chapter 8 - Air Pollution Chapter 9 - Oil Spill Chapter 10 - Environmental Effects of Wind Power

Chapter- 1

Introduction to Energy and the Environment

Energy consumption per capita per country (2001). Red hues indicate increase, green hues decrease of consumption during the 1990s. Energy and the environment are closely interlinked since energy comes via the environment and can have a negative effect on it. An increasing awareness of the effect of human activity on the natural environment has led to the use of sustainable energy and, in an increasingly populated world, the need for energy conservation and energy efficiency.

Energy Energy has been harnessed by humans for millennia. Initially it was with the use of fire for light, heat, cooking and for safety, and its use can be traced back at least 1.9 million years..As technology developed different methods of harnessing energy were discovered. We now use energy either directly or indirectly from the three sources of solar, nuclear and geothermal using a wide variety of technologies.

Environmental issues An increasing per capita demand and an increasing population is placing a greater strain on natural resources. These resources include undammed rivers, clean air and retaining natural landscapes. Unsustainable energy demands, collectively across all forms of energy generation and cumulatively for every unit of energy, affect the quality and quantity of natural resources.

Sustainable energy Sustainable energy is the provision of energy such that it meets the needs of the present without compromising the ability of future generations to meet their needs. A broader interpretation may allow inclusion of fossil fuels and nuclear fission as transitional sources while technology develops, as long as new sources are developed for future generations to use. A narrower interpretation includes only energy sources which are not expected to be depleted in a time frame relevant to the human race. Sustainable energy sources are most often regarded as including all renewable sources, such as biofuels, solar heating, solar power, wind power, geothermal power and tidal power. It usually also includes technologies that improve energy efficiency. Conventional fission power is sometimes referred to as sustainable, but this is controversial politically due to concerns about peak uranium, radioactive waste disposal and the risks of disaster due to accident, terrorism, or natural disaster.

Energy conservation Energy conservation is the practice of decreasing the quantity of energy used. It may be achieved through efficient energy use, in which case energy use is decreased while achieving a similar outcome, or by reduced consumption of energy services. Reduction in the amount of energy used reduces any harmful effects on the environment.

Politics A demand by an increasing sector of society, driven in a large part by environmentalists and academics, has caused organisations to address the effect of energy generation and demand on the environment. Because of the huge effect, both those already discovered and the future effects such as climate change, energy policies are developed. Energy policy is the manner in which a given entity (often governmental) has decided to address issues of energy development including energy production, distribution and consumption. The attributes of energy policy may include legislation, international treaties, incentives to investment, guidelines for energy conservation, taxation and other public policy techniques. Green parties consider energy to be a major policy platform.

Chapter- 2

Environmental Issues with Energy

Rate of world energy usage in terawatts (TW), 1965-2005. There are many environmental issues with energy with the largest being climate change due predominantly to the burning of fossil fuels and the direct impact of greenhouse gases on the Earths environment. In recent years there has been a trend towards the increased commercialization of various renewable energy sources. In the real world of consumption of fossil fuel resources which lead to global warming and climate change however little change is being made in many parts of the world. Chinese oil demand for instance, is projected to grow nearly 20% in the next six years, and that country already imports over half of the 8 million barrels a day it uses. If the

peak oil theory proves out, more explorations of viable alternative energy sources, could be more friendly to the environment. Rapidly advancing technologies can achieve a transition of energy generation, water and waste management, and food production towards better environmental and energy usage practices using methods of systems ecology and industrial ecology.

Issues Climate change

Global mean surface temperature anomaly relative to 1961–1990. Global warming and climate change due to human activity is generally accepted as being caused by anthropogenic greenhouse gas emissions. The majority of greenhouses gas emissions are due to burning fossil fuels with most of the rest due to deforestation. There is a highly publicized denial of climate change but the vast majority of scientists working in climatology accept that it is due to human activity. Some effects of human activity in the natural world regarding the use of natural resources, has brought about dire warnings in regard to sustainability issues by a variety of science based groups.

Biofuel use Biofuel is defined as solid, liquid or gaseous fuel obtained from relatively recently lifeless or living biological material and is different from fossil fuels, which are derived from long dead biological material. Also, various plants and plant-derived materials are used for biofuel manufacturing. Bio fuels are a renewable energy and can sustainable (carbon neutral) in terms of greenhouse gas emissions since they are in the carbon cycle for the short term.

Bio-diesel High use of bio-diesel leads to land use changes including deforestation.

Firewood Unsustainable firewood harvesting can lead to loss of biodiversity and erosion due to loss of forest cover. An example of this is a 40 year study done by the University of Leeds of African forests, which account for a third of the world's total tropical forest which demonstrates that Africa is a significant carbon sink. A climate change expert, Lee White states that "To get an idea of the value of the sink, the removal of nearly 5 billion tonnes of carbon dioxide from the atmosphere by intact tropical forests is at issue. According to the U.N. the continent is losing forest twice as fast as the rest of the world. "Once upon a time, Africa boasted seven million square kilometers of forest but a third of that has been lost, most of it to charcoal."

Fossil fuel use

Global fossil carbon emission by fuel type, 1800-2007 AD. The three fossil fuel types are coal, petroleum and natural gas. It was estimated by the Energy Information Administration that in 2006 primary sources of energy consisted of petroleum 36.8%, coal 26.6%, natural gas 22.9%, amounting to an 86% share for fossil fuels in primary energy production in the world. The burning of fossil fuels produces around 21.3 billion tonnes (21.3 gigatonnes) of carbon dioxide per year, but it is estimated that natural processes can only absorb about half of that amount, so there is a net increase of 10.65 billion tonnes of atmospheric carbon dioxide per year (one tonne of atmospheric carbon is equivalent to 44/12 or 3.7 tonnes of carbon). Carbon dioxide is one of the greenhouse gases that enhances radiative forcing and contributes to global warming, causing the average surface temperature of the Earth to rise in response, which climate scientists agree will cause major adverse effects.

Coal Coal is a made up predominately of carbon and when burnt it produces carbon dioxide, one of the major greenhouse gases.

Petroleum Gas Natural gas is often described as the cleanest fossil fuel, producing less carbon dioxide per joule delivered than either coal or oil, and far fewer pollutants than other fossil fuels. However, in absolute terms it does contribute substantially to global carbon emissions, and this contribution is projected to grow. According to the IPCC Fourth Assessment Report, in 2004 natural gas produced about 5,300 Mt/yr of CO2 emissions, while coal and oil produced 10,600 and 10,200 respectively (Figure 4.4); but by 2030, according to an updated version of the SRES B2 emissions scenario, natural gas would be the source of 11,000 Mt/yr, with coal and oil now 8,400 and 17,200 respectively. (Total global emissions for 2004 were estimated at over 27,200 Mt.) In addition, natural gas itself is a greenhouse gas far more potent than carbon dioxide when released into the atmosphere but is released in smaller amounts.

Electricity generation • •

Environmental impacts of dams Environmental concerns with electricity generation o Phase-out of incandescent light bulbs o Environmental effects of nuclear power

Wind power Compared to the environmental effects of traditional energy sources, the environmental effects of wind power are relatively minor. Wind power consumes no fuel, and emits no air pollution, unlike fossil fuel power sources. The energy consumed to manufacture and transport the materials used to build a wind power plant is equal to the new energy produced by the plant within a few months. While a wind farm may cover a large area of land, many land uses such as agriculture are compatible, with only small areas of turbine foundations and infrastructure made unavailable for use.

Mitigation Mitigation of energy issues can be addressed by the use of sustainable practices.

Sustainable transport •

Public transport, Cycling, Electric cars, Biofuels

Renewable energy •

Hydroelectricity, wind power, Solar energy

Economic instruments Various economic instruments can be used to steer society toward sustainable energy. Some of these methods include ecotaxes and emissions trading. Ecological economics aims to address some of the interdependence and coevolution of human economies and natural ecosystems over time and space.Environmental economics, is the mainstream economic analysis of the environment, which views the economy as a subsystem of the ecosystem, while ecological economics emphasis is upon preserving natural capital.Biophysical economics sometimes referred to as thermoeconomics is discussed in the field of ecological economics and relates directly to energy conversion, which itself is related to the fields of sustainability and sustainable development especially in the area of carbon burning.

Chapter- 3

Environmental Effects of Biodiesel

A number of environmental effects of biodiesel have emerged.

Greenhouse gas emissions

Calculation of Carbon Intensity of Soy biodiesel grown in the US and burnt in the UK, using figures calculated by the UK government for the purposes of the Renewable transport fuel obligation.

Graph of UK figures for the Carbon Intensity of Biodiesels and fossil fuels. This graph assumes that all biodiesels are burnt in their country of origin. It also assumes that the diesel is produced from pre-existing croplands rather than by changing land use An often mentioned incentive for using biodiesel is its capacity to lower greenhouse gas emissions compared to those of fossil fuels. If this is true or not depends on many factors. Especially the effects from land use change have potential to cause even more emissions than what would be caused by using fossil fuels alone. Carbon dioxide is one of the major greenhouse gases. Although the burning of biodiesel produces carbon dioxide emissions similar to those from ordinary fossil fuels, the plant feedstock used in the production absorbs carbon dioxide from the atmosphere when it grows. Plants absorb carbon dioxide through a process known as photosynthesis which allows it to store energy from sunlight in the form of sugars and starches. After the biomass is converted into biodiesel and burnt as fuel the energy and carbon is released again. Some of that energy can be used to power an engine while the carbon dioxide is released back into the atmosphere. When considering the total amount of greenhouse gas emissions it is therefore important to consider the whole production process and what indirect effects such production might cause. The effect on carbon dioxide emissions is highly dependent on production methods and the type of feedstock used. Calculating the carbon intensity of biofuels is a complex and inexact process, and is highly dependent on the assumptions made in the calculation. A calculation usually includes: • •

Emissions from growing the feedstock (e.g. Petrochemicals used in fertilizers) Emissions from transporting the feedstock to the factory

•

Emissions from processing the feedstock into biodiesel

Other factors can be very significant but are sometimes not considered. These include: • • • • •

Emissions from the change in land use of the area where the fuel feedstock is grown. Emissions from transportation of the biodiesel from the factory to its point of use The efficiency of the biodiesel compared with standard diesel The amount of Carbon Dioxide produced at the tail pipe. (Biodiesel can produce 4.7% more) The benefits due to the production of useful by-products, such as cattle feed or glycerine

If land use change is not considered and assuming today's production methods, biodiesel from rapeseed and sunflower oil produce 45%-65% lower greenhouse gas emissions than petrodiesel. However, there is ongoing research to improve the efficiency of the production process. Biodiesel produced from used cooking oil or other waste fat could reduce CO2 emissions by as much as 85%. As long as the feedstock is grown on existing cropland, land use change has little or no effect on greenhouse gas emissions. However, there is concern that increased feedstock production directly affects the rate of deforestation. Such clearcutting cause carbon stored in the forest, soil and peat layers to be released. The amount of greenhouse gas emissions from deforestation is so large that the benefits from lower emissions (caused by biodiesel use alone) would be negligible for hundreds of years. Biofuel produced from feedstocks such as palm oil could therefore cause much higher carbon dioxide emissions than some types of fossil fuels.

Deforestation If deforestation, and monoculture farming techniques were used to grow biofuel crops, biodiesel may become a serious threat to the environment: • • •

Increasing the emission of climate change gases rather than helping curb them Damaging ecosystems and biodiversity Exacerbating social conflict

The demand for cheap oil from the tropical regions is of rising concern. In order to increase production, the amount of arable land is being expanded at the cost of tropical rainforest. Feedstock oils produced in Asia, South America and Africa are currently less expensive than those produced in Europe and North America suggesting that imports to these wealthier nations are likely to increase in the future. In the Philippines and Indonesia forest clearing is already underway for the production of palm oil. Indigenous people are forced to move and their livelihood is destroyed when forest is cleared to make room for oil palm plantations. In some areas the use of pesticides for biofuel crops are disrupting clean water supplies, and the loss of habitat caused by deforestation is threatening many species of unique plants and animals. One

example is the already-shrinking populations of orangutans on the Indonesian islands of Borneo and Sumatra, which face extinction if deforestation continue at its projected rate. This should be compared with the ecological degradation associated with oil production. For instance, oil production from the Athabasca Oil Sands in Canada has required the clear cutting of vast swathes of the Boreal forest to create open pit mines, and the consumption of vast amounts of water and natural gas. Another example is the oil production in the Niger Delta, which has destroyed fisheries and mangrove forests, and led to health problems among the local population.

Pollution In the United States, biodiesel is the only alternative fuel to have successfully completed the Health Effects Testing requirements (Tier I and Tier II) of the Clean Air Act (1990). Biodiesel can reduce the direct tailpipe-emission of particulates, small particles of solid combustion products, on vehicles with particulate filters by as much as 20 percent compared with low-sulfur (< 50 ppm) diesel. Particulate emissions as the result of production are reduced by around 50 percent compared with fossil-sourced diesel. (Beer et al., 2004). Biodiesel has a higher cetane rating than petrodiesel, which can improve performance and clean up emissions compared to crude petro-diesel (with cetane lower than 40). Biodiesel contains fewer aromatic hydrocarbons: benzofluoranthene: 56% reduction; Benzopyrenes: 71% reduction.

Biodegradation A University of Idaho study compared biodegradation rates of biodiesel, neat vegetable oils, biodiesel and petroleum diesel blends, and neat 2-D diesel fuel. Using low concentrations of the product to be degraded (10 ppm) in nutrient and sewage sludge amended solutions, they demonstrated that biodiesel degraded at the same rate as a dextrose control and 5 times as quickly as petroleum diesel over a period of 28 days, and that biodiesel blends doubled the rate of petroleum diesel degradation through cometabolism.

Chapter- 4

Environmental Impact of Palm Oil

A village palm oil press "malaxeur" in Bandundu, Democratic Republic of the Congo. Palm oil, produced from the oil palm, is a basic source of income for many farmers in South East Asia, Central and West Africa, and Central America. It is locally used as a cooking oil, exported for use in many commercial food and personal care products and is converted into biofuel. It produces up to 10 times more oil per unit area as soyabeans, rapeseed or sunflowers. Oil palms produce 38% of vegetable oil output on 5% of the world’s vegetable-oil farmland. Palm oil is under increasing scrutiny in relation to its effects on the environment.

Statistics An estimated 1.5 million small farmers grow the crop in Indonesia, along with about 500,000 people directly employed in the sector in Malaysia, plus those connected with related industries. As of 2006, the cumulative land area of palm oil plantations is approximately 11,000,000 hectares (42,000 sq mi). In 2005 the Malaysian Palm Oil Association, responsible for about half of the world's crop, estimated that they manage about half a billion perennial carbon-sequestering palm trees. Demand for palm oil has been rising and is expected to climb further. Between 1967 and 2000 the area under cultivation in Indonesia expanded from less than 2,000 square kilometres (770 sq mi) to more than 30,000 square kilometres (12,000 sq mi). Deforestation in Indonesia for palm oil (and illegal logging) is so rapid that a 2007 United Nations Environment Programme (UNEP) report said that most of the country’s forest might be destroyed by 2022. The rate of forest loss has declined in the past decade. Global production is forecast at a record 46.9m tonnes in 2010, up from 45.3m in 2009, with Indonesia providing most of the increase.

Environmental issues

Satellite image showing deforestation in Malaysian Borneo to allow the plantation of oil palm.

Deforestation in Riau province, Sumatra, to make place for an oil palm plantation (2007) Rising demand is driving owners to clear tropical forest to plant oil palms.According to UNEP, at the current rate of intrusion into Indonesian national parks, it is likely that many protected rain forests will be severely degraded by 2012 through illegal hunting and trade, logging, and forest fires, including those associated with the rapid spread of palm oil plantations. There is growing concern that this will be harmful to the environment in several ways: • •

• •

Significant greenhouse gas emissions. Deforestation, mainly in tropical areas, accounts for up to one-third of total anthropogenic CO2 emissions. Habitat destruction, leading to the demise of critically endangered species (e.g. the Sumatran tiger, the Asian rhinoceros, and the Sumatran Orangutan.) Reduced biodiversity, including damage to biodiversity hotspots. Destruction of cash crops, such as fruit and rubber trees in Sarawak, Sabah and Kalimantan and Borneo, that belong to indigenous peoples (the Dayak), despite their frequent objections.

Greenhouse gas emissions Damage to peatland, partly due to palm oil production, is claimed to contribute to environmental degradation, including four percent of global greenhouse gas emissions and eight percent of all global emissions caused annually by burning fossil fuels, due to the clearing of large areas of rainforest for palm oil plantations. Many Indonesian and Malaysian rainforests lie atop peat bogs that store great quantities of carbon. Forest removal and bog drainage to make way for plantations releases this carbon. Environmental groups such as Greenpeace claim that this deforestation produces far more emissions than biofuels remove. Greenpeace identified Indonesian peatlands, unique tropical forests whose dense soil can be burned to release carbon emissions, that are being destroyed to make way for palm oil plantations. They represent massive carbon sinks, and they claim their destruction already accounts for four percent of annual global emissions. Greenpeace recorded peatland destruction in the Indonesian province of Riau on the island of Sumatra, home to 25 percent of Indonesia's palm oil plantations. Growers plan to expand the area under concession by more than 28,500 square kilometres (11,000 sq mi) which would deforest half of the province. Greenpeace claims this would have devastating consequences for Riau's peatlands, which have already been degraded by industrial development and store a massive 14.6 billion tonnes of carbon, roughly one year's greenhouse gas emissions. Research conducted by Greenpeace through its Forest Defenders Camp in Riau documents how a major Indonesian palm oil producer is engaging in large-scale, illegal destruction of peatland in flagrant violation of an Indonesian presidential order, as well as national forestry regulations. Palm oil from peatland is fed into the supply chain for global brands. FoE and Greenpeace both calculate that forests and peatlands that are replaced by palm oil plantations release more carbon dioxide than is saved by replacing diesel withbiofuels. Environmentalists and conservationists have been called upon to become palm oil farmers themselves, so they can use the profits to invest in their cause. It has been suggested that this is a more productive strategy than the current confrontational approach that threatens the livelihoods of millions of smallholders.

National differences

Household palm oil extraction in Democratic Republic of the Congo.

Indonesia and Malaysia In the two countries responsible for over 80% of world oil palm production, Indonesia and Malaysia, smallholders account for 35–40% of the total area of planted oil palm and as much as 33% of the output. Elsewhere, as in West African countries that produce mainly for domestic and regional markets, smallholders produce up to 90% of the annual harvest. In January 2008, the CEO of the Malaysian Palm Oil Council wrote a letter to the Wall Street Journal stating that Malaysia was aware of the need to pursue a sustainable palm oil industry.

Africa In Africa, the situation is very different compared to Indonesia or Malaysia. In its Human Development Report 2007-2008, the United Nations Development Programsays production of palm oil in West-Africa is largely sustainable, mainly because it is undertaken on a smallholder level without resort to diversity-damaging monoculture. The United Nations Food and Agriculture program is encouraging small farmers across Africa to grow palm oil, because the crop offers opportunities to improve livelihoods and incomes for the poor.

Increasing demand Food and cosmetics companies, including ADM, Unilever, Cargill, Procter & Gamble, Nestle, Kraft and Burger King, are driving the demand for new palm oil supplies, partly for products that contain non-hydrogenated solid vegetable fats, as consumers now demand fewer hydrogenated oils in food products that were previously high in trans fat content. Friends of the Earth concluded that the increase in demand also comes from biofuel, with producers now looking to use palm as a source.

Biodiesel Biodiesel made from palm oil grown on sustainable non-forest land and from established plantations effectively reduces greenhouse gas emissions. However, Greenpeace has concluded that "first generation" biodiesel extracted from new palm oil plantations may not on balance reduce emissions. If wood from forests cleared for palm plantations is burned instead of used for biodiesel, leaving forests untouched may keep more carbon out of the air. Although palm oil has a comparatively high yield, alternative vegetable fuel oil sources with such as jatropha may have a better net effect. Although palm requires less manual labor to harvest a given amount of oil than jatropha, the latter grows well in more marginal areas and requires less water.

Sustainability Greenpeace accuses major multinational companies of turning a blind eye to peatland destruction to supply low cost vegetable oil. The Roundtable on Sustainable Palm Oil, founded in 2004, gathers growers, processors, food companies, investors and NGOs to address this problem. Its purpose is to prod the industry into producing "sustainable" palm oil, product that is certified as not involving the destruction of important areas. Certified supply and demand have both grown slowly.

In the first year of trading only 30% of sustainable oil was sold as such. In 2010, sustainable purchases represented most of the 2 million certified tonnes produced. RSPO has struggled to set standards for greenhouse-gas emissions for plantations. Its members account for only 40% of production. Greenpalm is a certificate trading program which aims to tackle the environmental and social problems created by palm oil production. The purpose of the programme is to help producers can earn more for their crop through sustainable farming. Helped by $1 billion from Norway, In May, Indonesia announced a two-year moratorium on new concessions to clear natural forests and peatlands and its own rival to the RSPO, which is expected to restrict all producers.

Carbon credit programs Meanwhile, much of the recent investment in new palm plantations for biofuel has been part-funded through carbon credit projects through the Clean Development Mechanism; however the reputational risk associated with unsustainable palm plantations in Indonesia has now made many funds wary of investing there.

Persuading users In 2008 Unilever, an RSPO member, committed to use only palm oil which is certified as sustainable, by ensuring that the large companies and smallholders that supply it convert to sustainable production by 2015. This policy was in part a response to a Greenpeacestaged event which dispatched activists dressed as orang-utans to Unilever’s offices in London, Merseyside, in Rome and in Rotterdam. Dove, one of the company’s bestknown brands, was singled out by name. Nestlé a Swiss food giant, buys only 320,000 tons of palm oil a year and is an RSPO member. A 2010 spoof online advertisement shows an office worker eating a an orangutan finger made to look like a KitKat. Before the "ad", it had begun buying certified oil, but planned to limit itself to certified product only in 2015. On May 17th, 2010, after 1.5 million viewings and 200,000 protest e-mails, Nestlé suspended all purchases from Sinar Mas and other suppliers running “high-risk plantations or farms linked to deforestation”. Nestlé recruited a Swiss charity, The Forest Trust (TFT), to review its supply chain, auditing every supplier. World Wildlife Foundation (WWF) publishes an annual scorecard of the palm-oil policies of 59 European companies. As of 2009, twelve companies including giant retailer Metro, tied for worst, scoring 0. Sainsbury's, Marks & Spencer and Migros achieved the highest scores. In 2010, the Nature Conservancy took representatives of America’s National Farmers Union and the American Farmland Trust to Brazil to see how illegal forest clearance was “hurting US businesses by flooding markets with cheap and unsustainable products”. A

new report from David Gardiner & Associates, a consultancy, says that protecting the 13,000,000 hectares (50,000 sq mi) of mostly tropical forest that are lost annually to timber, cattle and agricultural production would boost American agricultural revenue by as much as $190 billion-270 billion between 2012 and 2030.

Chapter- 5

Environmental Effects of Coal

There are a number of adverse environmental effects of coal mining and burning.

Effects of mining •

• • • • • •

Release of carbon dioxide and methane, both of which are greenhouse gases causing climate change and global warming . Coal is the largest contributor to the human-made increase of CO2 in the atmosphere. Waste products including uranium, thorium, and other radioactive and heavy metal contaminants Acid rain Acid mine drainage (AMD) Interference with groundwater and water table levels Impact of water use on flows of rivers and consequential impact on other landuses Dust nuisance

tunnels, sometimes damaging infrastructure •

Rendering land unfit for the other uses

Coal mining causes a number of harmful effects. When coal surfaces are exposed, pyrite (iron sulfide), also known as "fool's gold", comes in contact with water and air and forms sulfuric acid. As water drains from the mine, the acid moves into the waterways, and as long as rain falls on the mine tailings the sulfuric acid production continues, whether the mine is still operating or not. This process is known as acid rock drainage (ARD) or acid mine drainage (AMD). If the coal is strip mined, the entire exposed seam leaches sulfuric acid, leaving the subsoil infertile on the surface and begins to pollute streams by acidifying and killing fish, plants, and aquatic animals which are sensitive to drastic pH shifts.

Coal mining produces methane, a potent greenhouse gas. Methane is the naturally occurring product of the decay of organic matter as coal deposits are formed with increasing depths of burial, rising temperatures, and rising pressures over geological time. A portion of the methane produced is absorbed by the coal and later released from the coal seam and surrounding disturbed strata during the mining process. Methane accounts for 10.5% of greenhouse gas emissions created through human activity. According to the Intergovernmental Panel on Climate Change, methane has a global warming potential 21 times greater than that of carbon dioxide on a 100 year time line. While burning coal in power plants is most harmful to air quality, due to the emission of dangerous gases, the process of mining can release pockets of hazardous gases. These gases may pose a threat to coal miners as well as a source of air pollution. This is due to the relaxation of pressure and fracturing of the strata during mining activity, which gives rise to serious safety concerns for the coal miners if not managed properly. The buildup of pressure in the strata can lead to explosions during or after the mining process if prevention methods, such as "methane draining", are not taken. Wherever it occurs in the world, strip mining severely alters the landscape, which damages the values of the natural environment in the surrounding land. Strip mining, or surface mining of coal completely eliminates existing vegetation, destroys the genetic soil profile, displaces or destroys wildlife and habitat, degrades air quality, alters current land uses, and to some extent permanently changes the general topography of the area mined. The community of micro organisms and nutrient cycling processes are upset by movement, storage, and redistribution of soil. Generally, soil disturbance and associated compaction result in conditions conducive to erosion. Soil removal from the area to be surface mined alters or destroys many natural soil characteristics, and may reduce its productivity for agriculture or biodiversity. Soil structure may be disturbed by pulverization or aggregate breakdown. Removal of vegetative cover and activities associated with construction of haul roads, stockpiling of topsoil, displacement of overburden and hauling of soil and coal increase the quantity of dust around mining operations. Dust degrades air quality in the immediate area, can have adverse impacts on vegetative life, and may constitute a health and safety hazard for mine workers and nearby residents. The land surface, often hundreds of acres, is dedicated to mining activities until it can be reshaped and reclaimed. If mining is allowed, resident human populations must be resettled off the mine site, and economic activities such as agriculture or hunting and gathering food or medicinal plants are displaced, at least temporarily. What becomes of the land surface after mining is determined by the manner in which mining is conducted. Surface mining can adversely impact the hydrology of a region. Deterioration of stream quality can result from acid mine drainage, toxic trace elements, high content of dissolved solids in mine drainage water, and increased sediment loads discharged to streams. Waste piles and coal storage piles can yield sediment to streams, and leached water from these piles can be acid and contain toxic trace elements. Surface waters may

be rendered unfit for agriculture, human consumption, bathing, or other household uses. Controlling these impacts requires careful management of surface water flows into and out of mining operations.

Effects on water Flood events can cause severe damage to improperly constructed or located coal haul roads, housing, coal crushing and washing plant facilities, waste and coal storage piles, settling basin dams, surface water diversion structures, and the mine itself. Besides the danger to life and property, large amounts of sediment and poor quality water may have detrimental effects many miles downstream from a mine site after a flood. Overall, it will cause a lot of poulltion in our drinking water. Ground water supplies may be adversely affected by surface mining. These impacts include drainage of usable water from shallow aquifers; lowering of water levels in adjacent areas and changes in flow directions within aquifers; contamination of usable aquifers below mining operations due to infiltration or percolation of poor quality mine water; and increased infiltration of precipitation on spoil piles. Where coal or carbonaceous shales are present, increased infiltration may result in increased runoff of poor quality water and erosion from spoil piles; recharge of poor quality water to shallow groundwater aquifers; or poor quality water flow to nearby streams. This may contaminate both ground water and nearby streams for long periods. Lakes formed in abandoned surface mining operations are more likely to be acid if there is coal or carbonaceous shale present in spoil piles, especially if these materials are near the surface and contain pyrites. Sulphuric acid is formed when minerals containing sulphide are oxidised through air contact, which could lead to acid rain. Leftover chemicals deposits from explosives are usually toxic and increase the salt quantity of mine water and even contaminating it.

Effects on wildlife Surface mining of coal causes direct and indirect damage to wildlife. The impact on wildlife stems primarily from disturbing, removing, and redistributing the land surface. Some impacts are short-term and confined to the mine site; others may have far reaching, long term effects. The most direct effect on wildlife is destruction or displacement of species in areas of excavation and spoil piling. Mobile wildlife species like game animals, birds, and predators leave these areas. More sedentary animals like invertebrates, many reptiles, burrowing rodents and small mammals may be directly destroyed. If streams, lakes, ponds or marshes are filled or drained, fish, aquatic invertebrates, and amphibians are destroyed. Food supplies for predators are reduced by destruction of these land and water species. Animal populations displaced or destroyed can eventually be

replaced from populations in surrounding ranges, provided the habitat is eventually restored. An exception could be extinction of a resident endangered species. Many wildlife species are highly dependent on vegetation growing in natural drainages. This vegetation provides essential food, nesting sites and cover for escape from predators. Any activity that destroys this vegetation near ponds, reservoirs, marshes, and wetlands reduces the quality and quantity of habitat essential for waterfowl, shore birds, and many terrestrial species. The commonly used head of hollow fill method for disposing of excess overburden is of particular significance to wildlife habitat in some locations. Narrow, steep sided, V shaped hollows near ridge tops are frequently inhabited by rare or endangered animal and plant species. Extensive placement of spoil in these narrow valleys eliminates important habitat for a wide variety of species, some of which may be rendered extinct. Broad and long lasting impacts on wildlife are caused by habitat impairment. The habitat requirements of many animal species do not permit them to adjust to changes created by land disturbance. These changes reduce living space. . Some species tolerate very little disturbance. In instances where a particularly critical habitat is restricted, such as a lake, pond, or primary breeding area, a species could be eliminated. The wide range of damage that could be done is severe. Large mammals and other animals displaced from their home ranges may be forced to use adjacent areas already stocked to carrying capacity. This overcrowding usually results in degradation of remaining habitat, lowered carrying capacity, reduced reproductive success, increased interspecies and intraspecies competition, and potentially greater losses to wildlife populations than the number of originally displaced animals. Degradation of aquatic habitats has often been a major impact from surface mining and may be apparent to some degree many miles from a mining site. Sediment contamination of surface water is common with surface mining. Sediment yields may increase 1000 times over their former level as a direct result of strip mining. . Permanent Regulatory Program Implementing Section 501(b) of the Surface Mining Control and Reclamation Act of 1977. . Preferred food and cover plants can be established in these openings to benefit a wide variety of wildlife. Under certain conditions, creation of small lakes in the mined area may also be beneficial. These lakes and ponds may become important water sources for a variety of wildlife inhabiting adjacent areas. Many lakes formed in mine pits are initially of poor quality as aquatic habitat after mining, due to lack of structure, aquatic vegetation, and food species. They may require habitat enhancement and management to be of significant wildlife valueneeded.

Loss of topsoil Removal of soil and rock overburden covering the coal resource, if improperly done, causes burial and loss of top soil, exposes parent material, and creates vast infertile wastelands. Pit and spoil areas are not capable of providing food and cover for most species of wildlife. Without rehabilitation, these areas must go through a weathering

period, which may take a few years or many decades, before vegetation is established and they become suitable habitat. With rehabilitation, impacts on some species are less severe. Humans cannot immediately restore natural biotic communities. We can, however, assist nature through reclamation of land and rehabilitation efforts geared to wildlife needs. Rehabilitation not geared to the needs of wildlife species, or improper management of other land uses after reclamation, can preclude reestablishment of many members of the original fauna. Surface mining operations and coal transportation facilities are fully dedicated to coal production for the life of a mine. Mining activities incorporating little or no planning to establish postmining land use objectives usually result in reclamation of disturbed lands to a land use condition not equal to the original use. Existing land uses such as livestock grazing, crop and timber production are temporarily eliminated from the mining area. High value, intensive land use areas like urban and transportation systems are not usually affected by mining operations. If mineral values are sufficient, these improvements may be removed to an adjacent area.

Coal seam fires Fires sometimes occur in coal beds underground. When coal beds are exposed, the fire risk is increased. Weathered coal can also increase ground temperatures if it is left on the surface. Almost all fires in solid coal are ignited by surface fires caused by people or lightning. Spontaneous combustion is caused when coal oxidizes and air flow is insufficient to dissipate heat, but this occurs only in stockpiles and waste piles, not in bedded coals underground. Where coal fires occur, there is attendant air pollution from emission of smoke and noxious fumes into the atmosphere. Coal seam fires may burn underground for decades, threatening destruction of forests, homes, schools, churches, roadways and other valuable infrastructure. Spontaneous combustion is common in coal stockpiles and refuse piles at mine sites.

Fly ash spills

Aerial photograph of Kingston Fossil Plant coal fly ash slurry spill site taken the day after the event The burning of coal leads to substantial fly ash sludge storage ponds. These can give way as one did at Kingston Fossil Plant

Historic resources Adverse impacts on geological features of human interest may occur in a surface mine area. Geomorphic and geophysical features and outstanding scenic resources may be sacrificed by indiscriminate mining. Paleontological, cultural, and other historic values may be endangered due to disruptive activities of blasting, ripping, and excavating coal.

Stripping of overburden eliminates and destroys all archeological and historic features unless they are removed beforehand.also is really bad for health.

Aesthetic effects Extraction of coal by surface mining disrupts virtually all aesthetic elements of the landscape, in some cases only temporarily. Alteration of land forms often imposes unfamiliar and discontinuous configurations. New linear patterns appear as material is extracted and waste piles are developed. Different colors and textures are exposed as vegetative cover is removed and overburden dumped to the side. Dust, vibration, and diesel exhaust odors are created, affecting sight, sound, and smell. Some members of local communities may find such impacts disturbing or unpleasant.

Socioeconomic effects Due to intensive mechanization, surface mines may require fewer workers than underground mines with equivalent production. The influence on human populations from surface mining is therefore not generally as significant as with underground mines. In low population areas, however, local populations cannot provide needed labor so there is migration to the area because new jobs are available at a mine. Unless adequate advance planning is done by government and mine operators, new populations may cause overcrowded schools, hospitals and demands on public services that cannot easily be met. Some social instability may be created in nearby communities by surface coal mining. Many impacts can be minimized but may not be eliminated entirely by use of best mining practices either voluntarily or to comply with government regulatory programs. Financial incentives to minimize costs of production may minimize use of best mining practices in the absence of effective regulation. Some temporary destruction of the land surface is an environmental price we pay for utilization of coal resources. The scale of disturbance, its duration, and the quality of reclamation are largely determined by management of the operation during mining. Mountaintop removal to remove coal is a large-scale negative change to the environment. Tops are removed from mountains or hills to expose thick coal seams underneath, and the soil and rock removed is deposited in nearby valleys, hollows and depressions, resulting in blocked and sometimes contaminated waterways. In some areas of the world, remediation is often delayed for decades. One of the legacies of coal mining is the low coal content waste forming slag heaps. In addition, all forms of mining are likely to generate areas where coal is stacked and where the coal has significant sulfur content, such coal heaps generate highly acidic, metalladen drainage when exposed to rainfall. These liquors can cause severe environmental damage to receiving water-courses. Coal mining releases approximately twenty toxic release chemicals, of which 85% is said to be managed on site.

Mine collapses Mine collapses, or mine subsidences, have a potential for major effects aboveground, which are especially devastating in built-up areas. German underground coal-mining, especially in North Rhine-Westphalia, has damaged thousands of houses, and the coal mining industries have set aside many millions in funding for future subsidence damages as part of their insurance and state subsidy schemes. In a particularly spectacular case in the German Saar region, another historical coal mining area, a suspected mine collapse in 2008 created an earthquake of force 4.0 on the Richter magnitude scale, causing some limited damage to houses. Previous smaller earthquakes had been increasingly common. Coal mining was temporarily suspended in the area.

Burning The combustion of coal, like any other fossil fuel, is an exothermic reaction between the fuel source and usually oxygen. Coal is made primarily of carbon, but also contains sulfur, oxygen, hydrogen, and nitrogen. During combustion, the reaction between coal and the air produces oxides of carbon, including carbon dioxide (CO2 - an important greenhouse gas), oxides of sulfur, mainly sulfur dioxide (SO2), and various oxides of nitrogen (NOx). Because of the hydrogen and nitrogen components of coal, hydrides and nitrides of carbon and sulfur are also produced during the combustion of coal in air. These could include hydrogen cyanide (HCN), sulfur nitrate (SNO3) and many other toxic substances. Further, acid rain may occur when the sulfur dioxide produced in the combustion of coal, reacts with oxygen to form sulfur trioxide (SO3), which then reacts with water molecules in the atmosphere to form sulfuric acid. The sulfuric acid (H2SO4) is returned to the Earth as acid rain. Flue gas desulfurization scrubbing systems, which use lime to remove the sulfur dioxide can reduce or eliminate the likelihood of acid rain. However, another form of acid rain is due to the carbon dioxide emissions of a coal plant. When released into the atmosphere, the carbon dioxide molecules react with water molecules, to very slowly produce carbonic acid (H2CO3). This, in turn, returns to the earth as a corrosive substance. This cannot be prevented as easily as sulfur dioxide emissions. Coal and coal waste products, including fly ash, bottom ash, and boiler slag, contain many heavy metals, including arsenic, lead, mercury, nickel, vanadium, beryllium, cadmium, barium, chromium, copper, molybdenum, zinc, selenium and radium, which are dangerous if released into the environment. Coal also contains low levels of uranium, thorium, and other naturally occurring radioactive isotopes whose release into the environment may lead to radioactive contamination. While these substances are trace impurities, enough coal is burned that significant amounts of these substances are released. However, John Gofman, M.D., Ph.D, (Professor Emeritus of Medical Physics at

the University of California, Berkeley, and the co-discoverer of Uranium-233) compared the radiation dose per megawatt-year from operation of a nuclear generating unit to the radiation dose from operation of a coal fired unit and found that the dose from natural nuclides associated with nuclear power would be 35-81 times higher than the dose from coal.

Studies about coal phase out and climate change In 2008 James E. Hansen and eight other scientists published "Target Atmospheric CO2: Where Should Humanity Aim?" calling for phasing out coal power completely by the year 2030. In 2008 Pushker Kharecha and James E. Hansen published a peer-reviewed scientific study analyzing the effect of a coal phase-out on atmospheric CO2 levels. Their baseline mitigation scenario was a phaseout of global coal emissions by 2050. The authors describe the scenario as follows: The second scenario, labeled Coal Phase-out, is meant to approximate a situation in which developed countries freeze their CO2 emissions from coal by 2012 and a decade later developing countries similarly halt increases in coal emissions. Between 2025 and 2050 it is assumed that both developed and developing countries will linearly phase out emissions of CO2 from coal usage. Thus in Coal Phase-out we have global CO2 emissions from coal increasing 2% per year until 2012, 1% per year growth of coal emissions between 2013 and 2022, flat coal emissions for 2023–2025, and finally a linear decrease to zero CO2 emissions from coal in 2050. These rates refer to emissions to the atmosphere and do not constrain consumption of coal, provided the CO2 is captured and sequestered. Oil and gas emissions are assumed to be the same as in the BAU [Business as Usual] scenario. Kharecha and Hansen also consider three other mitigation scenarios, all with the same coal phase-out schedule but each making different assumptions about the size of oil and gas reserves and the speed at which they are depleted. Under the Business as Usual scenario, atmospheric CO2 peaks at 563 parts per million (ppm) in the year 2100. Under the four coal phase-out scenarios, atmospheric CO2 peaks at 422–446 ppm between 2045 and 2060 and declines thereafter. The key implications of the study are as follows: a phase-out of coal emissions is the most important remedy for mitigating human-induced global warming; actions should be taken toward limiting or stretching out the use of conventional oil and gas; and strict emissions-based constraints are needed for future use of unconventional fossil fuels such as methane hydrates and tar sands. In the Greenpeace and EREC's Energy (R)evolution scenario, the world could eliminate all fossil fuel use by 2090

Mercury Emissions Mercury emissions from coal burning are concentrated as they work their way up the food chain and converted into methylmercury, a toxic compound that harms people who consume freshwater fish. In New York State, winds bring mercury from the coal-fired power plants of the Midwest, contaminating the waters of the Catskill Mountains. The mercury is consumed by worms, who are eaten by fish, and then by birds, including bald eagles. As of 2008, mercury contamination of bald eagles in the Catskills had reached new heights. Ocean fish account for the majority of human exposure to methylmercury; the sources of ocean fish methylmercury are not well understood. Coal-fired power plants shorten nearly 24,000 lives a year in the United States, including 2,800 from lung cancer.

By country China Coal provides most of China's current power, both for residential electricity and industry. China is hoping to move to nuclear power as it is cleaner and can deliver large amounts of power with a small amount of input fuel.

United States By the late 1930s, it was estimated that American coal mines produced about 2.3 million tons of sulfuric acid annually. In the Ohio River Basin, where twelve hundred operating coal mines drained an estimated annual 1.4 million tonnes of sulfuric acid into the waters in the 1960s and thousands of abandoned coal mines leached acid as well. In Pennsylvania alone, mine drainage had blighted 2,000 stream miles by 1967. In response to negative land effects of coal mining and the abundance of abandoned mines in the USA, the federal government enacted the Surface Mining Control and Reclamation Act of 1977, which requires reclamation plans for future coal mining sites. Reclamation plans must be approved and permitted by federal or state authorities before mining begins. As of 2003, over 2 million acres (8,000 km²) of previously mined lands have been reclaimed in the United States. Emissions from coal-fired power plants represents one of the two largest sources of carbon dioxide emissions, which are the main cause of global warming. Coal mining and abandoned mines also emit methane, another cause of global warming. Since the carbon content of coal is higher than oil, burning coal is a serious threat to the stability of the global climate, as this carbon forms CO2 when burned. Many other pollutants are present in coal power station emissions, as solid coal is more difficult to clean than oil, which is refined before use. A study commissioned by environmental groups claims that coal power plant emissions are responsible for tens of thousands of premature deaths annually in the United States alone. Modern power plants utilize a variety of techniques to limit

the harmfulness of their waste products and improve the efficiency of burning, though these techniques are not subject to standard testing or regulation in the U.S. and are not widely implemented in some countries, as they add to the capital cost of the power plant. To eliminate CO2 emissions from coal plants, carbon capture and storage has been proposed but has yet to be commercially used. The effects of sediment on aquatic wildlife vary with the species and amount of contamination. High sediment loads can kill fish directly, bury spawning beds, reduce light transmission, alter temperature gradients, fill in pools, spread stream flows over wider, shallower areas, and reduce production of aquatic organisms used as food by other species. These changes destroy the habitat of some valued species and may enhance habitat for less desirable species. Existing conditions are already marginal for some freshwater fish in the United States. Sedimentation of these waters can result in their elimination. The heaviest sediment pollution of a drainage normally comes within five to 25 years after mining. In some areas, unrevegetated spoil piles continue to erode even 50 to 65 years after mining. The presence of acid forming materials exposed as a result of surface mining can affect wildlife by eliminating habitat and by causing direct destruction of some species. Lesser concentrations can suppress productivity, growth rate, and reproduction of many aquatic species. Acids, dilute concentrations of heavy metals, and high alkalinity can cause severe wildlife damage in some areas. The duration of acidic waste pollution can be long term. Estimates of the time required to leach exposed acidic materials in the Eastern United States range from 800 to 3000 years. Surface mining operations have produced cliff-like highwalls as high as 200 feet (61 m) in the United States. Such highwalls may be created at the end of a surface mining operation where stripping becomes uneconomic, or where a mine reaches the boundary of a current lease or mineral ownership. These highwalls are hazards to people, wildlife, and domestic livestock. They may impede normal wildlife migration routes. Steep slopes also merit special attention because of the significance of impacts associated with them when mined. While impacts from contour mining on steep slopes are of the same type as all mining, the severity of these impacts increase as the degree of slope increases. This is due to increased difficulties in dealing with problems of erosion and land stability on steeper slopes. Mining operations in the United States must, under federal and state law, meet standards for protecting surface and ground waters from contamination, including AMD. To mitigate these problems, water is continuously monitored at coal mines. The five principal technologies used to control water flow at mine sites are: • • • • •

diversion systems, containment ponds, groundwater pumping systems, subsurface drainage systems, subsurface barriers.

In the case of AMD, contaminated water is generally pumped to a treatment facility that neutralizes the contaminants. The Environmental Protection Agency classified the 44 sites as potential hazards to communities, which means the waste sites could cause death and significant property damage if an event such as a storm, a terrorist attack or a structural failure caused a spill. They estimate that about 300 dry landfills and wet storage ponds are used around the country to store ash from coal-fired power plants. The storage facilities hold the noncombustible ingredients of coal and the ash trapped by equipment designed to reduce air pollution.

Coal seam fire

A coal seam fire near Denniston, New Zealand. A coal seam fire or mine fire is the underground smouldering of a coal deposit, often in a coal mine. Such fires have economic, social and ecological impacts. They are often started by lightning, grass, or forest fires, and are particularly insidious because they continue to smoulder underground after surface fires have been extinguished, sometimes for many years, before flaring up and restarting forest and brush fires nearby. They propagate in a creeping fashion along mine shafts and cracks in geologic structures.

Coal fires are a serious problem because hazards to health and safety and the environment include toxic fumes, reigniting grass, brush, or forest fires, and subsidence of surface infrastructure such as roads, pipelines, electric lines, bridge supports, buildings and homes. Whether started by humans or by natural causes, coal seam fires continue to burn for decades or even centuries until either the fuel source is exhausted; a permanent groundwater table is encountered; the depth of the burn becomes greater than the ground’s capacity to subside and vent; or humans intervene. Because they burn underground, coal seam fires are extremely difficult and costly to extinguish, and are unlikely to be suppressed by rainfall. There are strong similarities between coal fires and peat fires. Internationally, thousands of underground coal fires are burning now. The problem is most acute in industrializing, coal-rich nations such as China. Global coal fire emission are estimated to include 40 tons of mercury going into the atmosphere annually, and three percent of the world's annual CO2 emissions.

Origins Coal seam fires can be divided into near-surface fires, in which seams extend to the surface and the oxygen required for their ignition comes from the atmosphere, and fires in deep underground mines, where the oxygen comes from the ventilation. Mine fires may begin as a result of an industrial accident, generally involving a gas explosion. Historically, some mine fires were started when bootleg mining was stopped by authorities, usually by blowing the mine up. Many recent mine fires have started from people burning trash in a landfill that was in proximity to abandoned coal mines, including the much publicized Centralia, Pennsylvania, fire, which has been burning since 1962. Of the hundreds of mine fires in the United States burning today, most are found in the state of Pennsylvania. Some fires along coal seams are natural occurrences. Some coals may self-ignite at temperatures as low as 40 °C (104 °F) for brown coal in the right conditions of moisture and grain size. The fire usually begins a few decimeters inside the coal at a depth in which the permeability of the coal allows the inflow of air but in which the ventilation does not remove the heat which is generated. Two basic factors determine whether spontaneous combustion occurs or not, the ambient temperature and the grain size: • •

The higher the ambient temperature, the faster the oxidation reactions and the greater the heat release inside the grain. The larger the grain, the harder it is for the heat arising on the inside to be dissipated to the outside, i.e., the faster the spontaneous combustion. The poor heat loss is because the porous or crushed material usually has low thermal conductivity; it acts like insulation.

Wildfires (lightning-caused or others) can ignite the coal closer to the surface or entrance, and the smouldering fire can spread through the seam, creating subsidence that may open further seams to oxygen and spawn future wildfires when the fire breaks to the surface. Prehistoric clinker outcrops in the American West are the result of prehistoric coal fires that left a residue that resists erosion better than the matrix, leaving buttes and mesa. It is estimated that Australia's Burning Mountain, the oldest known coal fire, has burned for 6,000 years. Globally, thousands of inextinguishable mine fires are burning, especially in China, where poverty, lack of government regulations and runaway development combine to create an environmental disaster. Modern strip mining exposes smoldering coal seams to the air, revitalizing the flames. Rural Chinese in coal-bearing regions often dig coal for household use, abandoning the pits when they become unworkably deep, leaving highly combustible coal dust exposed to the air. Using satellite imagery to map China's coal fires resulted in the discovery of many previously unknown fires. The oldest coal fire in China is in Baijigou and is said to have been burning since the Qing Dynasty (before 1912).

Detection Before attempting to extinguish a near-surface coal seam fire, its location and underground extent should be determined as precisely as possible. Besides studying the geographic, geologic and infrastructural context, information can be gained from direct measurements. These include: • •

•

•

Temperature measurements of the land surface, in fissures and boreholes, for example using pyrometers Gas measurements to characterize the fire ventilation system (amount and velocity) and the gas composition, so that the combustion reactions can be described Geophysical measurements on the ground and from airplanes and helicopters to establish the extent of conductivity or other underground parameters. For example, conductivity measurements map humidity changes near the fire; measuring the magnetism can determine changes in the magnetic characteristics of the adjacent rock caused by heat Remote sensing from aircraft and satellites. High resolution optical mapping, thermal imaging and hyperspectral data play a role. Underground coal fires of several hundred to over a thousand degrees Celsius may raise the surface temperature by only a few degrees. This order of magnitude is similar to the temperature difference between the sunlit and shadowed slopes of a slag heap or sand dune. Infrared detecting equipment is able to track the fire's location as the fire heats the ground on all sides of it. However, remote sensing techniques are unable to distinguish individual fires burning near one another and often lead to undercounting of actual fires. They may also have some difficulties distinguishing coal seam fires from forest fires.

Underground coal mines can be equipped with permanently installed sensor systems. These relay pressure, temperature, airflow and gas composition measurements to the safety monitoring personnel, giving them early warning of any problems.

Environmental impact

Besides destruction of the affected areas, coal fires emit gases that contribute to global warming, such as carbon dioxide, carbon monoxide, sulphur dioxide and methane. China's coal fires, which consume an estimated 20 – 200 million tons of coal a year, make up as much as 1 percent of the global carbon dioxide emissions from fossil fuels. One of the most visible changes will be the effect of subsidence upon the landscape. Another local environmental effect, can include the presence of plants or animals that are aided by the coal fire. The prevalence of otherwise non-native plants can depend upon the fire's duration and the size of the affected area. For example, near a coal fire in Germany, many Mediterranean insects and spiders were identified in a region with cold winters, and it is believed raised ground temperatures above the fires permitted their survival.

Extinguishing coal fires In order to thrive, a fire requires fuel and oxygen. Firefighting involves finding an appropriate methodology which addresses the interaction of these two factors for the specific fire in question. A fire can be isolated from its fuel source, for example through firebreaks or fireproof barriers. Many fires, particularly those on steep slopes, can be completely excavated. In the case of near-surface coal seam fires, the influx of oxygen in the air can be interrupted by covering the area or installing gas-tight barriers. Another possibility is to hinder the outflow of combustion gases so that the fire is quenched by its own exhaust fumes. Energy can be removed by cooling, usually by injecting large amounts of water. However, if any remaining dry coal absorbs water, the resulting heat of absorption can lead to re-ignition of a once-quenched fire as the area dries. Accordingly, more energy must be removed than the fire generates. In practice these methods are combined, and each case depends on the resources available. This is especially true for

water, for example in arid regions, and for covering material, such as loess or clay, to prevent contact with the atmosphere. Extinguishing underground coal fires, which sometimes exceed temperatures of 540°C (1,000°F), is both highly dangerous and very expensive. Near-surface coal seam fires are routinely extinguished in China following a standard method basically consisting of the following phases: • • • • •

Smoothing the surface above the fire with heavy equipment to make it fit for traffic. Drilling holes in the fire zone about 20 m apart down to the source of the fire, following a regular grid. Injecting water or mud in the boreholes long term, usually 1 to 2 years. Covering the entire area with an impermeable layer about 1 m thick, e.g., of loess. Planting vegetation to the extent the climate allows.

Efforts are underway to refine this method, for example with additives to the quenching water or with alternative extinguishing agents. Underground coal seam fires are customarily quenched by inertization through mine rescue personnel. Toward this end the affected area is isolated by dam constructions in the galleries. Then an inert gas, usually nitrogen, is introduced for a period of time, usually making use of available pipelines. In 2004, the Chinese government claimed success in extinguishing a mine fire at a colliery near Urumqi in China's Xinjiang province that had been burning since 1874. However, a March 2008 Time magazine article quotes researcher Steven Q. Andrews as saying, "I decided to go to see how it was extinguished, and flames were visible and the entire thing was still burning.... They said it was put out, and who is to say otherwise?" A jet engine unit, known as Gorniczy Agregat Gasniczy (GAG), was developed in Poland and successfully utilised for fighting coal fires and displacing firedamp in mines.

Current research and new developments in extinguishing fires Time magazine reported in July 2010 that less expensive alternatives for extinguishing coal seam fires were beginning to reach the market, including special heat-resistant grouts and a fire-smothering nitrogen foam, with other innovative solutions on the way.

List of mine fires Some of the more notable mine fires around the world are listed below.

Australia • •

•

Burning Mountain - a naturally occurring, slow combusting underground coal seam Morwell, Victoria - the Great Morwell open cut mine caught fire in March 1902 and burned for over a month. It was extinguished by breaching the nearby Morwell River with explosives to flood the mine. The fire was found to have been caused by sabotage from incendiary devices. Hazelwood Power Station - a 2 km coal face in the Hazelwood open cut mine was set alight by a bushfire in October 2006.

Canada • • • •

Elkford, British Columbia Merritt, British Columbia Carmacks, Yukon Smoking Hills

China In China, the world’s largest coal producer with an annual output around 2.5 billion tons, coal fires are a serious problem. It has been estimated that some 10-200 million tons of coal uselessly burn annually, and that the same amount again is made inaccessible to mining . Coal fires extend over a belt across the entire north China, whereby over one hundred major fire areas are listed, each of which contains many individual fire zones. They are concentrated in the provinces of Xinjiang, Inner Mongolia and Ningxia. Beside losses from burned and inaccessible coal, these fires contribute to air pollution and considerably increased levels of greenhouse gas emissions and have thereby become a problem which has gained international attention. But at the same time, some of the most intensive fire fighting activities worldwide are being undertaken in China. New quenching methods are being developed in a coal fire research project as part of a SinoGerman coal fire research initiative.

Germany In Planitz, now a part of the city of Zwickau, a coal seam that had been burning since 1476 could only be quenched in 1860. In Dudweiler (Saarland) a coal seam fire ignited around 1668 and is still burning today. This so-called Burning Mountain ("Brennender Berg") soon became a tourist attraction and was even visited by Johann Wolfgang von Goethe. Also well-known is the so-called Stinksteinwand (stinking stone wall) in Schwalbenthal on the eastern slope of the Hoher Meißner, where several seams caught fire centuries ago after lignite coal mining ceased; combustion gas continues to reach the surface today.

India In India, as of 2010, 68 fires were burning beneath a 58-square-mile (150 km2) region of the Jhairia coalfield near Dhanbad.

Indonesia Coal and peat fires in Indonesia are often ignited by forest fires near outcrop deposits at the surface. It is difficult to determine when a forest fire is started by a coal seam fire, or vice versa, in the absence of eye witnesses. The most common cause of forest fires and haze in Indonesia is intentional burning of forest to clear land for plantation crops of pulp wood, rubber and palm oil. No accurate count of coal seam fires has been completed in Indonesia. Only a minuscule fraction of the country has been surveyed for coal fires. The best data available come from a study based on systematic, on-the-ground observation. In 1998, a total of 125 coal fires were located and mapped within a 2-kilometer strip either side of a 100-kilometer stretch of road north of Balikpapan to Samarinda in East Kalimantan, using hand-held Global Positioning System (GPS) equipment. Extrapolating this data to areas on Kalimantan and Sumatera underlain by known coal deposits, it was estimated that more than 250,000 coal seam fires may have been burning in Indonesia in 1998. Coal seam fires are ignited in Indonesia by land clearing practices which use fire, often starting forest fires. In 1982-83 one of the largest forest fires in this century raged for several months through an estimated 5 million hectares of Borneo's tropical rainforests. A fire season usually occurs every 3–5 years, when the climate in parts of Indonesia becomes exceptionally dry from June to November due to the El Nino Southern Oscillation off the west coast of South America half a world away. Since 1982, fire has been a recurring feature on the Islands of Borneo and Sumatera, burning large areas in 1987, 1991, 1994, 1997–98, 2001 and 2004. In October 2004 smoke from land clearing again covered substantial portions of Borneo and Sumatra, disrupting air travel, increasing hospital admissions, and extending to portions of Brunei, Singapore and Malaysia. Coal outcrops are so common in Indonesia it is virtually certain these fires ignited new coal seam fires.

New Zealand • • • •

Burnett's Face, West Coast Strongman Mine, West Coast Wangaloa, Otago Pike River Mine, West Coast

Norway In 1944 Longyearbyen Mine #2 on Svalbard was set alight by sailors from the Tirpitz on its final sortie outside of Norwegian coastal waters. The mine continued to burn for 20 years, while some of the areas were subsequently mined from the reconstructed Mine #2b.

South Africa •

Transvaal and Delagoa Bay Collieries near Emalahleni (formerly known as Witbank), Mpumalanga has been burning since the mine was abandoned in 1953.

United States Many coalfields in the USA are subject to spontaneous ignition. The federal Office of Surface Mining (OSM) maintains a database (AMLIS), which in 1999 listed 150 fire zones. In mid-2010, according to OSM, more than 100 fires were burning beneath nine states, most of them in Colorado, Kentucky, Pennsylvania, Utah and West Virginia. But geologists say many fires go unreported, so that the actual number of them is nearer to 200, across 21 states. In Pennsylvania, 45 fire zones are known, the most famous being the fire in the Centralia mine in the hard coal region of Columbia County, which has been burning since 1962. In Colorado coal fires have arisen as a consequence of fluctuations in the groundwater level, which can increase the temperature of the coal up to 30 °C, enough to cause it to spontaneously ignite. The Powder River Basin in Wyoming and Montana contains some 800 billion tons of brown coal, and the Lewis and Clark Expedition (1804 to 1806) reported fires there. Fires have been a natural occurrence in this area for about three million years and have shaped the landscape. For example, an area about 4,000 square kilometers in size is covered with coal clinker, some of it in Theodore Roosevelt National Park, where there is a spectacular view of fiery red coal clinker from Scoria Point. • • • • • • •

Laurel Run, Pennsylvania New Castle, Colorado New Straitsville, Ohio San Toy, Ohio Sego, Utah Vanderbilt, Pennsylvania Centralia, Pennsylvania (Started by garbage fire in an abandoned mine shaft.)

Chapter- 6

Major Effects of Coal Mining on Environment

Acid rain

Processes involved in acid deposition (note that only SO2 and NOx play a significant role in acid rain). Acid rain is a rain or any other form of precipitation that is unusually acidic, i.e. elevated levels of hydrogen ions (low pH). It can have harmful effects on plants, aquatic animals, and infrastructure through the process of wet deposition. Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides which react with the water molecules in the atmosphere to produce acids. Governments have made efforts since the 1970s to reduce the release of sulfur dioxide into the atmosphere with positive results. However, it can also be caused naturally by the splitting of nitrogen compounds by the energy produced by lightning strikes, or the release of sulfur dioxide into the atmosphere by volcano eruptions.

Definition "Acid rain" is a popular term referring to the deposition of wet (rain, snow, sleet, fog, cloudwater, and dew) and dry (acidifying particles and gases) acidic components. A more accurate term is “acid deposition”. Distilled water, once carbon dioxide is removed, has a neutral pH of 7. Liquids with a pH less than 7 are acidic, and those with a pH greater than 7 are Alkaline. “Clean” or unpolluted rain has a slightly acidic pH of over 5.7, because carbon dioxide and water in the air react together to form carbonic acid, but unpolluted rain also contains other chemicals. H2O (l) + CO2 (g)

H2CO3 (aq)

Carbonic acid then can ionize in water forming low concentrations of hydronium and carbonate ions: H2O (l) + H2CO3 (aq)

HCO3− (aq) + H3O+ (aq)

Acid deposition as an environmental issue would include additional acids to H2CO3.

History

Trees killed by acid rain The corrosive effect of polluted, acidic city air on limestone and marble was noted in the 17th century by John Evelyn, who remarked upon the poor condition of the Arundel marbles. Since the Industrial Revolution, emissions of sulfur dioxide and nitrogen oxides to the atmosphere have increased. In 1852, Robert Angus Smith was the first to show the relationship between acid rain and atmospheric pollution in Manchester, England. Though acidic rain was discovered in 1852, it was not until the late 1960s that scientists began widely observing and studying the phenomenon. The term "acid rain" was coined in 1872 by Robert Angus Smith. Canadian Harold Harvey was among the first to research a "dead" lake. Public awareness of acid rain in the U.S increased in the 1970s after The New York Times promulgated reports from the Hubbard Brook Experimental Forest in

New Hampshire of the myriad deleterious environmental effects demonstrated to result from it. Occasional pH readings in rain and fog water of well below 2.4 have been reported in industrialized areas. Industrial acid rain is a substantial problem in China and Russia and areas down-wind from them. These areas all burn sulfur-containing coal to generate heat and electricity. The problem of acid rain not only has increased with population and industrial growth, but has become more widespread. The use of tall smokestacks to reduce local pollution has contributed to the spread of acid rain by releasing gases into regional atmospheric circulation. Often deposition occurs a considerable distance downwind of the emissions, with mountainous regions tending to receive the greatest deposition (simply because of their higher rainfall). An example of this effect is the low pH of rain (compared to the local emissions) which falls in Scandinavia.

History of acid rain in the United States In 1980, the U.S. Congress passed an Acid Deposition Act. This Act established a 10year research program under the direction of the National Acidic Precipitation Assessment Program (NAPAP). NAPAP looked at the entire problem. It enlarged a network of monitoring sites to determine how acidic the precipitation actually was, and to determine long term trends, and established a network for dry deposition. It looked at the effects of acid rain and funded research on the effects of acid precipitation on freshwater and terrestrial ecosystems, historical buildings, monuments, and building materials. It also funded extensive studies on atmospheric processes and potential control programs. In 1991, NAPAP provided its first assessment of acid rain in the United States. It reported that 5% of New England Lakes were acidic, with sulfates being the most common problem. They noted that 2% of the lakes could no longer support Brook Trout, and 6% of the lakes were unsuitable for the survival of many species of minnow. Subsequent Reports to Congress have documented chemical changes in soil and freshwater ecosystems, nitrogen saturation, decreases in amounts of nutrients in soil, episodic acidification, regional haze, and damage to historical monuments. Meanwhile, in 1990, the US Congress passed a series of amendments to the Clean Air Act. Title IV of these amendments established the Acid Rain Program, a cap and trade system designed to control emissions of sulfur dioxide and nitrogen oxides. Title IV called for a total reduction of about 10 million tons of SO2 emissions from power plants. It was implemented in two phases. Phase I began in 1995, and limited sulfur dioxide emissions from 110 of the largest power plants to a combined total of 8.7 million tons of sulfur dioxide. One power plant in New England (Merrimack) was in Phase I. Four other plants (Newington, Mount Tom, Brayton Point, and Salem Harbor) were added under other provisions of the program. Phase II began in 2000, and affects most of the power plants in the country. During the 1990s, research has continued. On March 10, 2005, EPA issued the Clean Air Interstate Rule (CAIR). This rule provides states with a solution to the problem of power

plant pollution that drifts from one state to another. CAIR will permanently cap emissions of SO2 and NOx in the eastern United States. When fully implemented, CAIR will reduce SO2 emissions in 28 eastern states and the District of Columbia by over 70 percent and NOx emissions by over 60 percent from 2003 levels. Overall, the Program's cap and trade program has been successful in achieving its goals. Since the 1990s, SO2 emissions have dropped 40%, and according to the Pacific Research Institute, acid rain levels have dropped 65% since 1976. However, this was significantly less successful than conventional regulation in the European Union, which saw a decrease of over 70% in SO2 emissions during the same time period. In 2007, total SO2 emissions were 8.9 million tons, achieving the program's long term goal ahead of the 2010 statutory deadline. The EPA estimates that by 2010, the overall costs of complying with the program for businesses and consumers will be $1 billion to $2 billion a year, only one fourth of what was originally predicted.

Emissions of chemicals leading to acidification The most important gas which leads to acidification is sulfur dioxide. Emissions of nitrogen oxides which are oxidized to form nitric acid are of increasing importance due to stricter controls on emissions of sulfur containing compounds. 70 Tg(S) per year in the form of SO2 comes from fossil fuel combustion and industry, 2.8 Tg(S) from wildfires and 7-8 Tg(S) per year from volcanoes.

Natural phenomena The principal natural phenomena that contribute acid-producing gases to the atmosphere are emissions from volcanoes. Thus, for example, fumaroles from Laguna Caliente crater of Poás Volcano create extremely high amounts of acid rain and fog with acidity 2 of pH, clearing an area of any vegetation and frequently causing irritation to the eyes and lungs of inhabitants in nearby settlements. Acid-producing gasses are created also by biological processes that occur on the land, in wetlands, and in the oceans. The major biological source of sulfur containing compounds is dimethyl sulfide. Nitric acid in rainwater is an important source of fixed nitrogen for plant life, and is also produced by electrical activity in the atmosphere such as lightning. Acidic deposits have been detected in glacial ice thousands of years old in remote parts of the globe. Soils of Coniferous forests are naturally very acidic due to the shedding of needles and this phenomenon should not be confused with acid rain.

Human activity

The coal-fired Gavin Power Plant in Cheshire, Ohio The principal cause of acid rain is sulfur and nitrogen compounds from human sources, such as electricity generation, factories, and motor vehicles. Coal power plants are one of the most polluting. The gases can be carried hundreds of kilometers in the atmosphere before they are converted to acids and deposited. In the past, factories had short funnels to let out smoke but this caused many problems locally; thus, factories now have taller smoke funnels. However, dispersal from these taller stacks causes pollutants to be carried farther, causing widespread ecological damage. Also, livestock production plays a major role. It is responsible for almost two-thirds of all anthropogenic sources of ammonia produced through human activities, which contributes significantly to acid rain.

Chemical processes Combustion of fuels creates sulfur dioxide and nitric oxides. They are converted into sulfuric acid and nitric acid.

Gas phase chemistry In the gas phase sulfur dioxide is oxidized by reaction with the hydroxyl radical via an intermolecular reaction: SO2 + OH· → HOSO2· which is followed by: HOSO2· + O2 → HO2· + SO3 In the presence of water, sulfur trioxide (SO3) is converted rapidly to sulfuric acid: SO3 (g) + H2O (l) → H2SO4 (l) Nitrogen dioxide reacts with OH to form nitric acid: NO2 + OH· → HNO3

Chemistry in cloud droplets When clouds are present, the loss rate of SO2 is faster than can be explained by gas phase chemistry alone. This is due to reactions in the liquid water droplets. Hydrolysis Sulfur dioxide dissolves in water and then, like carbon dioxide, hydrolyses in a series of equilibrium reactions: SO2 (g) + H2O SO2·H2O SO2·H2O H+ + HSO3− HSO3− H+ + SO32− Oxidation There are a large number of aqueous reactions that oxidize sulfur from S(IV) to S(VI), leading to the formation of sulfuric acid. The most important oxidation reactions are with ozone, hydrogen peroxide and oxygen (reactions with oxygen are catalyzed by iron and manganese in the cloud droplets).

Acid deposition Wet deposition Wet deposition of acids occurs when any form of precipitation (rain, snow, etc.) removes acids from the atmosphere and delivers it to the Earth's surface. This can result from the deposition of acids produced in the raindrops or by the precipitation removing the acids

either in clouds or below clouds. Wet removal of both gases and aerosols are both of importance for wet deposition.

Dry deposition Acid deposition also occurs via dry deposition in the absence of precipitation. This can be responsible for as much as 20 to 60% of total acid deposition. This occurs when particles and gases stick to the ground, plants or other surfaces.

Adverse effects

This chart shows that not all fish, shellfish, or the insects that they eat can tolerate the same amount of acid; for example, frogs can tolerate water that is more acidic (i.e., has a lower pH) than trout. Acid rain has been shown to have adverse impacts on forests, freshwaters and soils, killing insect and aquatic life-forms as well as causing damage to buildings and having impacts on human health.

Surface waters and aquatic animals Both the lower pH and higher aluminium concentrations in surface water that occur as a result of acid rain can cause damage to fish and other aquatic animals. At pHs lower than 5 most fish eggs will not hatch and lower pHs can kill adult fish. As lakes and rivers become more acidic biodiversity is reduced. Acid rain has eliminated insect life and some fish species, including the brook trout in some lakes, streams, and creeks in geographically sensitive areas, such as the Adirondack Mountains of the United States. However, the extent to which acid rain contributes directly or indirectly via runoff from the catchment to lake and river acidity (i.e., depending on characteristics of the surrounding watershed) is variable. The United States Environmental Protection

Agency's (EPA) website states: "Of the lakes and streams surveyed, acid rain caused acidity in 75 percent of the acidic lakes and about 50 percent of the acidic streams".

Soils Soil biology and chemistry can be seriously damaged by acid rain. Some microbes are unable to tolerate changes to low pHs and are killed. The enzymes of these microbes are denatured (changed in shape so they no longer function) by the acid. The hydronium ions of acid rain also mobilize toxins such as aluminium, and leach away essential nutrients and minerals such as magnesium. 2 H+ (aq) + Mg2+ (clay)

2 H+ (clay) + Mg2+ (aq)

Soil chemistry can be dramatically changed when base cations, such as calcium and magnesium, are leached by acid rain thereby affecting sensitive species, such as sugar maple (Acer saccharum).

Forests and other vegetation

Effect of acid rain on a forest, Jizera Mountains, Czech Republic Adverse effects may be indirectly related to acid rain, like the acid's effects on soil (see above) or high concentration of gaseous precursors to acid rain. High altitude forests are

especially vulnerable as they are often surrounded by clouds and fog which are more acidic than rain. Other plants can also be damaged by acid rain, but the effect on food crops is minimized by the application of lime and fertilizers to replace lost nutrients. In cultivated areas, limestone may also be added to increase the ability of the soil to keep the pH stable, but this tactic is largely unusable in the case of wilderness lands. When calcium is leached from the needles of red spruce, these trees become less cold tolerant and exhibit winter injury and even death.

Human health Scientists have suggested direct links to human health. Fine particles or soot, a large fraction of which are formed from the same gases as acid rain (sulfur dioxide and nitrogen dioxide), have been shown to cause premature deaths and illnesses such as cancer and other diseases. For more information on the health effects of aerosols see particulate health effects.

Other adverse effects

Effect of acid rain on statues Acid rain can also damage buildings and historic monuments, especially those made of rocks such as limestone and marble containing large amounts of calcium carbonate.

Acids in the rain react with the calcium compounds in the stones to create gypsum, which then flakes off. CaCO3 (s) + H2SO4 (aq)

CaSO4 (aq) + CO2 (g) + H2O (l)

The effects of this are commonly seen on old gravestones, where acid rain can cause the inscriptions to become completely illegible. Acid rain also increases the oxidation rate of metals, in particular copper and bronze.

Affected areas Places with significant impact by acid rain around the globe include most of eastern Europe from Poland northward into Scandinavia, the eastern third of the United States, and southeastern Canada. Other affected areas include the southeastern coast of China and Taiwan.

Prevention methods Technical solutions Many coal-burning power plants use Flue gas desulfurization (FGD) to remove sulfurcontaining gases from their stack gases. For a typical coal-fired power station, FGD will remove 95 percent or more of the SO2 in the flue gases. An example of FGD is the wet scrubber which is commonly used. A wet scrubber is basically a reaction tower equipped with a fan that extracts hot smoke stack gases from a power plant into the tower. Lime or limestone in slurry form is also injected into the tower to mix with the stack gases and combine with the sulfur dioxide present. The calcium carbonate of the limestone produces pH-neutral calcium sulfate that is physically removed from the scrubber. That is, the scrubber turns sulfur pollution into industrial sulfates. In some areas the sulfates are sold to chemical companies as gypsum when the purity of calcium sulfate is high. In others, they are placed in landfill. However, the effects of acid rain can last for generations, as the effects of pH level change can stimulate the continued leaching of undesirable chemicals into otherwise pristine water sources, killing off vulnerable insect and fish species and blocking efforts to restore native life. Vehicle emissions control reduces emissions of nitrogen oxides from motor vehicles.

International treaties A number of international treaties on the long range transport of atmospheric pollutants have been agreed e.g. Sulphur Emissions Reduction Protocol under the Convention on Long-Range Transboundary Air Pollution. Most European countries and Canada have signed the treaties.

Emissions trading In this regulatory scheme, every current polluting facility is given or may purchase on an open market an emissions allowance for each unit of a designated pollutant it emits. Operators can then install pollution control equipment, and sell portions of their emissions allowances they no longer need for their own operations, thereby recovering some of the capital cost of their investment in such equipment. The intention is to give operators economic incentives to install pollution controls. The first emissions trading market was established in the United States by enactment of the Clean Air Act Amendments of 1990. The overall goal of the Acid Rain Program established by the Act is to achieve significant environmental and public health benefits through reductions in emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx), the primary causes of acid rain. To achieve this goal at the lowest cost to society, the program employs both regulatory and market based approaches for controlling air pollution.

Acid mine drainage

Yellow boy in a stream receiving acid drainage from surface coal mining. Acid mine drainage (AMD), or acid rock drainage (ARD), refers to the outflow of acidic water from (usually abandoned) metal mines or coal mines. However, other areas where the earth has been disturbed (e.g. construction sites, subdivisions, transportation corridors, etc.) may also contribute acid rock drainage to the environment. In many localities the liquid that drains from coal stocks, coal handling facilities, coal washeries, and even coal waste tips can be highly acidic, and in such cases it is treated as acid rock drainage. Acid rock drainage occurs naturally within some environments as part of the rock weathering process but is exacerbated by large-scale earth disturbances characteristic of mining and other large construction activities, usually within rocks containing an abundance of sulfide minerals.

Occurrence

In this case, the pyrite has dissolved away yielding a cube shape and residual gold. This break down is the main driver of acid mine drainage. Sub-surface mining often progresses below the water table, so water must be constantly pumped out of the mine in order to prevent flooding. When a mine is abandoned, the pumping ceases, and water floods the mine. This introduction of water is the initial step in most acid rock drainage situations. Tailings piles or ponds may also be a source of acid rock drainage. After being exposed to air and water, oxidation of metal sulfides (often pyrite, which is iron-sulfide) within the surrounding rock and overburden generates acidity. Colonies of bacteria and archaea greatly accelerate the decomposition of metal ions, although the reactions also occur in an abiotic environment. These microbes, called extremophiles for their ability to survive in harsh conditions, occur naturally in the rock, but limited water and oxygen supplies usually keep their numbers low. Special extremophiles known as acidophiles especially favor the low pH levels of abandoned mines. In particular, Acidithiobacillus ferrooxidans is a key contributor to pyrite oxidation.

Metal mines may generate highly acidic discharges where the ore is a sulfide mineral or is associated with pyrite. In these cases the predominant metal ion may not be iron but rather zinc, copper, or nickel. The most commonly mined ore of copper, chalcopyrite, is itself a copper-iron-sulfide and occurs with a range of other sulfides. Thus, copper mines are often major culprits of acid mine drainage.

Chemistry The chemistry of oxidation of pyrites, the production of ferrous ions and subsequently ferric ions, is very complex, and this complexity has considerably inhibited the design of effective treatment options. Although a host of chemical processes contribute to acid mine drainage, pyrite oxidation is by far the greatest contributor. A general equation for this process is: 2FeS2(s) + 7O2(g) + 2H2O(l) ? 2Fe2+(aq) + 4SO42-(aq) + 4H+(aq) The oxidation of the sulfide to sulfate solubilizes the ferrous iron (iron(II)), which is subsequently oxidized to ferric iron (iron(III)): 4Fe2+(aq) + O2(g) + 4H+(aq) ? 4Fe3+(aq) + 2H2O(l) Either of these reactions can occur spontaneously or can be catalyzed by microorganisms that derive energy from the oxidation reaction. The ferric irons produced can also oxidize additional pyrite and oxidize into ferrous ions: FeS2(s) + 14Fe3+(aq) + 8H2O(l) ? 15Fe2+(aq) + 2SO42-(aq) + 16H+(aq) The net effect of these reactions is to release H+, which lowers the pH and maintains the solubility of the ferric ion. Traditionally, the character of acid mine drainage is determined by its acidity (mg/L), which is measured by titrating AMD with sodium hydroxide solution from the AMD initial pH till pH 8.3. Then calculate the moles of NaOH that consumed by one liter of AMD, and transfer the mole number into the weight of CaCO3. It is the value of acidity (mg/L) of AMD. Hence, the direct meaning of acidity is: weight of CaCO3 needed to neutralize the pH of 1 liter AMD. However, acidity can not best represent AMD’s characters. Some AMDs have same acidity values, even same pH value, but of different properties. Because the AMD acidity includes two components: hydrogen ions and dissolved metal ions. This can be seen clearly from the AMD acidity titration curves. The AMD acidity titration curve is shaped like a staircase. Vertical part shows the process OH- ions neutralizing H+ ions, which increases the pH of water. Horizontal part

indicates OH- ions precipitate metal ions into metal hydroxides, which will act as a buffer, using hydroxide from the titrant, keeping the pH constant for a brief time until a specific metal has completely precipitated. Most metal hydroxides (except Na and K) are insoluble in water and have specific solubility products. When pH reaches certain level the metal ions will precipitate and be eliminated from the water. This forms the stair steps of the titration curve. In different AMD the metal concentration may range from 500mg/L to 0.1mg/L. If assuming the highest concentration allowed for each metal is 0.1mmole/L, use metals’ precipitation products, we can calculate the criteria pH for each metal in water. Higher than the pH criteria the metal concentration is lower than 0.1mmole/L. The following table shows the experimental and theoretical pH criteria of metals in AMD Metal Fe+3 Al+3 Cu+2/Mn Zn+2/Ni+2 Fe+2 pH1 <3.2 3-4.5 5-6.5 6.5-8 5.5-6.5 2 pH 2.93 4.43 6.60/9.33 7.83/8.22 8.95 pH1 values are experiment data pH2 values are calculated from metal hydroxide solubility products, assuming metal concentration is 0.1mmole/L In real situation the following factors can affect the metal precipitation process, therefore in the experiment pH of precipitation spans around 1-1.5: 1. There are microbial and organic in the natural AMDs, which affect metal ion activities greatly. 2. During the titration process Fe+2 ions are quickly oxidized into Fe+3 in the air and precipitate as more insoluble Fe(OH)3. This lowers Fe+2 ions precipitation pH. (usually AMD titrations are not conducted under N2 flow). 3. For Cu+2, Ni+2 and Zn+2, there are competitions between precipitates of hydroxide and carbonate. 4. In low pH AMDs Mn+2 ions are stable, as pH increases during the titration, Mn+2 is oxidized and precipitated as MnO2, This also lowers Mn precipitation pH. 5. When iron and manganese occur together (which is relatively common), manganese will not be removed from solution until all the ferrous iron is removed. This is because ferrous iron reduces - and redissolves - insoluble manganese oxides. Once iron is removed, manganese can be precipitated, either by raising water pH above 9.5 (rapid reaction) or by promoting microbial oxidation at neutral-alkaline pH (slower reaction). As indicated above, manganese oxide precipitates tend to promote manganese precipitation at lower pH (ca. 7.5-8.5), but this reaction is somewhat slower than direct precipitation at elevated pH.

The major advantage of titration curve method is: It is simple, convenient and low cost. It can show water problem quickly and clearly. It helps to explain the AMD forming procedure and helps to find the treat method.

Effects Effects on pH

The Tinto River in Spain. In some acid mine drainage systems temperatures reach 117 degrees Fahrenheit (47 °C), and the pH can be as low as -3.6. Acid mine drainage causing organisms can thrive in waters with pH very close to zero. Negative pH occurs when water evaporates from already acidic pools thereby increasing the concentration of hydrogen ions. About half of the coal mine discharges in Pennsylvania have pH under 5 standard units. However, a significant portion of mine drainage in both the bituminous and anthracite regions of Pennsylvania is alkaline, because limestone in the overburden neutralizes acid before the drainage emanates.

Acid mine drainage has recently been a hindrance to the completion of the construction of Interstate 99 near State College, Pennsylvania, but this acid rock drainage didn't come from a mine: pyritic rock was unearthed during a road cut and then used as filler material in the I-99 construction. A similar situation developed at the Halifax airport in Canada. It is from these and similar experiences that the term acid rock drainage has emerged as being preferable to acid mine drainage, thereby emphasizing the general nature of the problem.

Yellow boy When the pH of acid mine drainage is raised past 3, either through contact with fresh water or neutralizing minerals, previously soluble Iron(III) ions precipitate as Iron(III) hydroxide, a yellow-orange solid colloquially known as yellow boy. Other types of iron precipitates are possible, including iron oxides and oxyhydroxides. All these precipitates can discolor water and smother plant and animal life on the streambed, disrupting stream ecosystems (a specific offense under the Fisheries Act in Canada). The process also produces additional hydrogen ions, which can further decrease pH. Research is currently being conducted as to the feasibility of recovering yellow boy and other iron precipitates for use as commercial pigments.

Trace metal and semi-metal contamination Many acid rock discharges also contain elevated levels of potentially toxic metals, especially nickel and copper with lower levels of a range of trace and semi-metal ions such as lead, arsenic, aluminium, and manganese. In the coal belt around the south Wales valleys in the UK highly acidic nickel-rich discharges from coal stocking sites have proved to be particularly troublesome.

Treatment Oversight In the United Kingdom, many discharges from abandoned mines are exempt from regulatory control. In such cases the Environment Agency working with partners such as the Coal Authority have provided some innovative solutions, including constructed wetland solutions such as on the River Pelenna in the valley of the River Afan near Port Talbot and the constructed wetland next to the River Neath at Ynysarwed. Although abandoned underground mines produce most of the acid mine drainage, some recently mined and reclaimed surface mines have produced ARD and have degraded local ground-water and surface-water resources. Acidic water produced at active mines must be neutralized to achieve pH 6-9 before discharge from a mine site to a stream is permitted. In Canada, work to reduce the effects of acid mine drainage is concentrated under the Mine Environment Neutral Drainage (MEND) program. Total liability from acid rock

drainage is estimated to be between $2 billion and $5 billion CAD. Over a period of eight years, MEND claims to have reduced ARD liability by up to $400 million CAD, from an investment of $17.5 million CAD.

Methods

Lime neutralization By far, the most commonly used commercial process for treating acid mine drainage is lime precipitation in a high-density sludge process. In this application, a slurry of lime is dispersed into a tank containing acid mine drainage and recycled sludge to increase water pH about ~9. At this pH, most toxic metals become insoluble and precipitate, aided by the presence of recycled sludge. Optionally, air may be introduced in this tank to oxidize iron and manganese and assist in their precipitation. The resulting slurry is directed to a sludge-settling vessel, such as a clarifier. In that vessel, clean water will overflow for release, whereas settled metal precipitates (sludge) will be recycled to the acid mine drainage treatment tank, with a sludge-wasting side stream. A number of variations of this process exist, as dictated by the chemistry of ARD, its volume, and other factors. Generally, HDS-generated sludge also contains gypsum and unreacted lime, which enhance both its settleability and resistance to re-acidification and metal mobilization. Less complex variants of this process, such as simple lime neutralization, may involve no more than a lime silo, mixing tank and settling pond. These systems are far less costly to build, but are also less efficient (i.e., longer reaction times are required, and they produce a discharge with higher trace metal concentrations, if present). They would be suitable for relatively small flows or less complex acid mine drainage.

Carbonate neutralization Generally, limestone or other calcareous strata that could neutralize acid are lacking or deficient at sites that produce acidic rock drainage. Limestone chips may be introduced into sites to create a neutralizing effect. Where limestone has been used, such as at Cwm Rheidol in mid Wales, the positive impact has been much less than anticipated because of the creation of an insoluble calcium sulfate layer on the limestone chips, binding the material and preventing further neutralization.

Ion exchange Cation exchange processes have previously been investigated as a potential treatment for acid mine drainage. The principle is that an ion exchange resin can remove potentially toxic metals (anionic resins), or chlorides and sulfates (cationic resins) from mine water. Once the contaminants are adsorbed, the exchange sites on resins must be regenerated, which typically requires expensive reagents and generates a brine that is difficult to dispose. A South African company claims to have developed a patented ion-exchange process that treats mine effluents (and AMD) economically, but such claims remain unsubstantiated at present.

Constructed wetlands Constructed wetlands systems have been proposed during the 1980s to treat acid mine drainage generated by the abandoned coal mines in Eastern Appalachia. Generally, the wetlands receive near-neutral water, after it has been neutralized by (typically) a limestone-based treatment process. Metal precipitation occurs from their oxidation at near-neutral pH, complexation with organic matter, precipitation as carbonates or sulfides. The latter results from sediment-borne anaerobic bacteria capable of reverting sulfate ions into sulfide ions. These sulfide ions can then bind with heavy metal ions, precipitating heavy metals out of solution and effectively reversing the entire process. The attractiveness of a constructed wetlands solution lies in its relative low cost. They are limited by the metal loads they can deal with (either from high flows or metal concentrations), though current practitioners have succeeded in developing constructed wetlands that treat high volumes and/or highly acidic water (with adequate pretreatment). Typically, the effluent from constructed wetland receiving near-neutral water will be well-buffered at between 6.5-7.0 and can readily be discharged. Some of metal precipitates retained in sediments are unstable when exposed to oxygen (e.g., copper sulfide or elemental selenium), and it is very important that the wetland sediments remain largely or permanently submerged. An example of an effective constructed wetland is on the Afon Pelena in the River Afan valley above Port Talbot where highly ferruginous discharges from the Whitworth mine have been successfully treated.

Precipitation of metal sulfides Most base metals in acidic solution precipitate in contact with free sulfide, e.g. from H2S or NaHS. Solid-liquid separation after reaction would produce a base metal-free effluent that can be discharged or further treated to reduce sulfate, and a metal sulfide concentrate with possible economic value. As an alternative, several researchers have investigated the precipitation of metals using biogenic sulfide. In this process, Sulfate-reducing bacteria oxidize organic matter using sulfate, instead of oxygen. Their metabolic products include bicarbonate, which can neutralize water acidity, and hydrogen sulfide, which forms highly insoluble precipitates with many toxic metals. Although promising, this process has been slow in being adopted for a variety of technical reasons.

Metagenomic study of acid mine drainage With the advance of Large-scale sequencing strategies, genomes of microorganisms in the acid mine drainage community are directly sequenced from the environment. The nearly full genomic constructs allows new understanding of the community and able to reconstruct their metabolic pathways. Our knowledge of Acidophiles in acid mine

drainage remains rudimentary: we know of many more species associated with ARD than we can establish roles and functions.

List of selected acid mine drainage sites worldwide This list includes both mines producing acid mine drainage and river systems significantly affected by such drainage. It is by no means complete, as worldwide, several thousands of such sites exist.

North America • • • • • • • • • • • • •

Argo Tunnel, Idaho Springs, Colorado, USA Berkeley Pit superfund site, covering the Clark Fork River and 50,000 acres (200 km²) in and around Butte, Montana, USA Britannia Beach, British Columbia, Canada Clinch-Powell River system, Virginia and Tennessee, USA Iron Mountain Mine, Shasta County, California, USA Monday Creek, Ohio, USA The Irwin Syncline in Southwestern Pennsylvania Pronto mine tailings site, Elliot Lake area, Ontario, Canada North Fork of Kentucky River, Kentucky, USA Cheat River Watershed, West Virginia, USA Copperas Brook Watershed, from the Elizabeth Mine in S. Strafford, Vermont, impacting the Ompompanoosuc River Davis Pyrite Mine in NW Massachusetts Hughes bore hole, Pennsylvania

Europe • • • • •

Avoca, Wicklow, Ireland Aznalcollar mine on the Agrio River, Spain Wheal Jane, Cornwall, England Parys Mountain mine, Anglesey, Wales Tinto River, Spain

Africa •

West Rand, Witwatersrand, South Africa

Oceania • •

Queen River, Tasmania, Australia King River, Tasmania, Australia

Chapter- 7

Environmental Issues with Petroleum

A beach after an oil spill. There are a number of environmental issues with petroleum as a result of it being toxic to almost all forms of life. The possibility of climate change exists. Petroleum, commonly referred to as oil, is closely linked to virtually all aspects of present society, especially for transportation and heating for both homes and for commercial activities.

Issues

Toxicity

Petroleum distillates contaminate surface runoff and kill almost all life Crude oil is a mixture of many different kinds of organic compounds, many of which are highly toxic and cancer causing (carcinogenic). Oil is "acutely lethal" to fish, that is it kills fish quickly, at a concentration of 4000 parts per million (ppm) (0.4%). "It only takes one quart of motor oil to make 250,000 gallons of ocean water toxic to wildlife." This is the equivalent of a concentration of 1 ppm. Crude oil and petroleum distillates cause birth defects. Benzene is present in both crude oil and gasoline and is known to cause leukemia in humans. The compound is also known to lower the white blood cell count in humans, which would leave people exposed to it more susceptible to infections. "Studies have linked benzene exposure in the mere parts per billion (ppb) range to terminal leukemia, Hodgkins lymphoma, and other blood and immune system diseases within 5-15 years of exposure."

Exhaust

Petroleum diesel exhaust from a truck When oil or petroleum distillates are burned usually the combustion is not complete. This means that incompletely burned compounds are created in addition to just water and carbon dioxide. The other compounds are often toxic to life. Examples are carbon monoxide and methanol. Also, fine particulates of soot blacken humans' and other animals' lungs and cause heart problems or death. Soot is cancer causing (carcinogenic).

Acid rain

Trees killed by acid rain, an unwanted side effect of burning petroleum High temperatures created by the combustion of petroleum cause nitrogen gas in the surrounding air to oxidize, creating nitrous oxides. Nitrous oxides, along with sulfur dioxide from the sulfur in the oil, combine with water in the atmosphere to create acid rain. Acid rain causes many problems such as dead trees and acidified lakes with dead fish. Coral reefs in the world's oceans are killed by acidic water caused by acid rain. Acid rain leads to increased corrosion of machinery and structures (large amounts of capital), and to the slow destruction of important archaeological structures such as the marble ruins in Rome and Greece.

Climate change Humans burning large amounts of petroleum create large amounts of CO2 (carbon dioxide) gas that traps heat in the earth's atmosphere. Also certain organic compounds, such as methane released from petroleum drilling or from the petroleum itself, trap heat several times more efficiently than CO2. Soot blocks the sun from reaching the earth and could cause cooling of the earth's atmosphere.

Oil spills Oil spills kill plants and wildlife, and render water undrinkable.

Oil shale Winning of petroleum from oil shale creates pollution problems

Volatile organic compounds Volatile organic compounds (VOCs) are gases or vapours emitted by various solids and liquids, many of which have short- and long-term adverse effects on human health and the environment. VOCs from petroleum are toxic and foul the air, and some like benzene are extremely toxic, carcinogenic and cause DNA damage. Benzene often makes up about 1% of crude oil and gasoline. Benzene is present in automobile exhaust.

Waste oil

Waste oil in the form of motor oil Waste oil is used oil containing breakdown products and impurities from use. Some examples of waste oil are used oils such as hydraulic oil, transmission oil, brake fluids, motor oil, crankcase oil, gear box oil and synthetic oil. Many of the same problems associated with natural petroleum exist with waste oil. When waste oil from vehicles drips out engines over streets and roads, the oil travels into the water table bringing with it such toxins as benzene. This poisons both soil and drinking water. Runoff from storms carries waste oil into rivers and oceans, poisoning them as well.

Mitigation Conservation/Phasing out • •

Creating laws to completely phase out the use of petroleum (Sweden's 15 year plan) Making use of petroleum more efficiently via better technology

Substitution of other energy sources •

Using "cleaner" energy sources such as natural gas and biodiesel, especially in critical areas like cities where there are people.

Use of biomass instead of petroleum • • •

It is said that anything that can be made from oil can be made from cellulose, that is fibrous plant material such as from hemp. Plastics can be created from cellulose instead of from oil. Lubricants like motor oil and grease can be made from plants and animal fat.

Safety measures • •

Decreasing the risk of spills False floors at gasoline stations to catch gasoline and oil drips from making it into the water table

Chapter- 8

Air Pollution

Air pollution from World War II production

Smog over Santiago, Chile Air pollution is the introduction of chemicals, particulate matter, or biological materials that cause harm or discomfort to humans or other living organisms, or cause damage to the natural environment or built environment, into the atmosphere. The atmosphere is a complex dynamic natural gaseous system that is essential to support life on planet Earth. Stratospheric ozone depletion due to air pollution has long been recognized as a threat to human health as well as to the Earth's ecosystems. Indoor air pollution and urban air quality are listed as two of the world's worst pollution problems in the 2008 Blacksmith Institute World's Worst Polluted Places report.

Pollutants

Before flue gas desulfurization was installed, the emissions from this power plant in New Mexico contained excessive amounts of sulfur dioxide.

Schematic drawing, causes and effects of air pollution: (1) greenhouse effect, (2) particulate contamination, (3) increased UV radiation, (4) acid rain, (5) increased ground level ozone concentration, (6) increased levels of nitrogen oxides. An air pollutant is known as a substance in the air that can cause harm to humans and the environment. Pollutants can be in the form of solid particles, liquid droplets, or gases. In addition, they may be natural or man-made. Pollutants can be classified as primary or secondary. Usually, primary pollutants are directly emitted from a process, such as ash from a volcanic eruption, the carbon monoxide gas from a motor vehicle exhaust or sulfur dioxide released from factories. Secondary pollutants are not emitted directly. Rather, they form in the air when primary pollutants react or interact. An important example of a secondary pollutant is ground level ozone — one of the many secondary pollutants that make up photochemical smog. Some pollutants may be both primary and secondary: that is, they are both emitted directly and formed from other primary pollutants. About 4 percent of deaths in the United States can be attributed to air pollution, according to the Environmental Science Engineering Program at the Harvard School of Public Health. Major primary pollutants produced by human activity include:

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Sulfur oxides (SOx) - especially sulfur dioxide, a chemical compound with the formula SO2. SO2 is produced by volcanoes and in various industrial processes. Since coal and petroleum often contain sulfur compounds, their combustion generates sulfur dioxide. Further oxidation of SO2, usually in the presence of a catalyst such as NO2, forms H2SO4, and thus acid rain. This is one of the causes for concern over the environmental impact of the use of these fuels as power sources. Nitrogen oxides (NOx) - especially nitrogen dioxide are emitted from high temperature combustion. Can be seen as the brown haze dome above or plume downwind of cities. Nitrogen dioxide is the chemical compound with the formula NO2. It is one of the several nitrogen oxides. This reddish-brown toxic gas has a characteristic sharp, biting odor. NO2 is one of the most prominent air pollutants. Carbon monoxide - is a colorless, odorless, non-irritating but very poisonous gas. It is a product by incomplete combustion of fuel such as natural gas, coal or wood. Vehicular exhaust is a major source of carbon monoxide. Carbon dioxide (CO2) - a colorless, odorless, non-toxic greenhouse gas emitted from combustion, cement production, and respiration Volatile organic compounds - VOCs are an important outdoor air pollutant. In this field they are often divided into the separate categories of methane (CH4) and non-methane (NMVOCs). Methane is an extremely efficient greenhouse gas which contributes to enhanced global warming. Other hydrocarbon VOCs are also significant greenhouse gases via their role in creating ozone and in prolonging the life of methane in the atmosphere, although the effect varies depending on local air quality. Within the NMVOCs, the aromatic compounds benzene, toluene and xylene are suspected carcinogens and may lead to leukemia through prolonged exposure. 1,3-butadiene is another dangerous compound which is often associated with industrial uses.

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Particulate matter - Particulates, alternatively referred to as particulate matter (PM) or fine particles, are tiny particles of solid or liquid suspended in a gas. In contrast, aerosol refers to particles and the gas together. Sources of particulate matter can be man made or natural. Some particulates occur naturally, originating from volcanoes, dust storms, forest and grassland fires, living vegetation, and sea spray. Human activities, such as the burning of fossil fuels in vehicles, power plants and various industrial processes also generate significant amounts of aerosols. Averaged over the globe, anthropogenic aerosols—those made by human activities—currently account for about 10 percent of the total amount of aerosols in our atmosphere. Increased levels of fine particles in the air are linked to health hazards such as heart disease, altered lung function and lung cancer.

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Persistent free radicals connected to airborne fine particles could cause cardiopulmonary disease.

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Toxic metals, such as lead, cadmium and copper. Chlorofluorocarbons (CFCs) - harmful to the ozone layer emitted from products currently banned from use.

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Ammonia (NH3) - emitted from agricultural processes. Ammonia is a compound with the formula NH3. It is normally encountered as a gas with a characteristic pungent odor. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to foodstuffs and fertilizers. Ammonia, either directly or indirectly, is also a building block for the synthesis of many pharmaceuticals. Although in wide use, ammonia is both caustic and hazardous. Odors — such as from garbage, sewage, and industrial processes Radioactive pollutants - produced by nuclear explosions, war explosives, and natural processes such as the radioactive decay of radon.

Secondary pollutants include: •

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Particulate matter formed from gaseous primary pollutants and compounds in photochemical smog. Smog is a kind of air pollution; the word "smog" is a portmanteau of smoke and fog. Classic smog results from large amounts of coal burning in an area caused by a mixture of smoke and sulfur dioxide. Modern smog does not usually come from coal but from vehicular and industrial emissions that are acted on in the atmosphere by sunlight to form secondary pollutants that also combine with the primary emissions to form photochemical smog. Ground level ozone (O3) formed from NOx and VOCs. Ozone (O3) is a key constituent of the troposphere (it is also an important constituent of certain regions of the stratosphere commonly known as the Ozone layer). Photochemical and chemical reactions involving it drive many of the chemical processes that occur in the atmosphere by day and by night. At abnormally high concentrations brought about by human activities (largely the combustion of fossil fuel), it is a pollutant, and a constituent of smog. Peroxyacetyl nitrate (PAN) - similarly formed from NOx and VOCs.

Minor air pollutants include: • •

A large number of minor hazardous air pollutants. Some of these are regulated in USA under the Clean Air Act and in Europe under the Air Framework Directive. A variety of persistent organic pollutants, which can attach to particulate matter.

Persistent organic pollutants (POPs) are organic compounds that are resistant to environmental degradation through chemical, biological, and photolytic processes. Because of this, they have been observed to persist in the environment, to be capable of long-range transport, bioaccumulate in human and animal tissue, biomagnify in food chains, and to have potential significant impacts on human health and the environment.

Sources

Dust storm approaching Stratford, Texas

Controlled burning of a field outside of Statesboro, Georgia in preparation for spring planting

Sources of air pollution refer to the various locations, activities or factors which are responsible for the releasing of pollutants in the atmosphere. These sources can be classified into two major categories which are: Anthropogenic sources (human activity) mostly related to burning different kinds of fuel •

"Stationary Sources" include smoke stacks of power plants, manufacturing facilities (factories) and waste incinerators, as well as furnaces and other types of fuel-burning heating devices

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"Mobile Sources" include motor vehicles, marine vessels, aircraft and the effect of sound etc.

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Chemicals, dust and controlled burn practices in agriculture and forestry management. Controlled or prescribed burning is a technique sometimes used in forest management, farming, prairie restoration or greenhouse gas abatement. Fire is a natural part of both forest and grassland ecology and controlled fire can be a tool for foresters. Controlled burning stimulates the germination of some desirable forest trees, thus renewing the forest.

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Fumes from paint, hair spray, varnish, aerosol sprays and other solvents

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Waste deposition in landfills, which generate methane. Methane is not toxic; however, it is highly flammable and may form explosive mixtures with air. Methane is also an asphyxiant and may displace oxygen in an enclosed space. Asphyxia or suffocation may result if the oxygen concentration is reduced to below 19.5% by displacement

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Military, such as nuclear weapons, toxic gases, germ warfare and rocketry

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Dust from natural sources, usually large areas of land with little or no vegetation. Methane, emitted by the digestion of food by animals, for example cattle. Radon gas from radioactive decay within the Earth's crust. Radon is a colorless, odorless, naturally occurring, radioactive noble gas that is formed from the decay of radium. It is considered to be a health hazard. Radon gas from natural sources can accumulate in buildings, especially in confined areas such as the basement and it is the second most frequent cause of lung cancer, after cigarette smoking.

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Smoke and carbon monoxide from wildfires. Vegetation, in some regions, emits environmentally significant amounts of VOCs on warmer days. These VOCs react with primary anthropogenic pollutants— specifically, NOx, SO2, and anthropogenic organic carbon compounds—to produce a seasonal haze of secondary pollutants. Volcanic activity, which produce sulfur, chlorine, and ash particulates.

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Emission factors Air pollutant emission factors are representative values that people attempt to relate the quantity of a pollutant released to the ambient air with an activity associated with the release of that pollutant. These factors are usually expressed as the weight of pollutant divided by a unit weight, volume, distance, or duration of the activity emitting the pollutant (e.g., kilograms of particulate emitted per megagram of coal burned). Such factors facilitate estimation of emissions from various sources of air pollution. In most cases, these factors are simply averages of all available data of acceptable quality, and are generally assumed to be representative of long-term averages. The United States Environmental Protection Agency has published a compilation of air pollutant emission factors for a multitude of industrial sources. The United Kingdom, Australia, Canada and many other countries have published similar compilations, as well as the European Environment Agency.

Indoor air quality (IAQ) A lack of ventilation indoors concentrates air pollution where people often spend the majority of their time. Radon (Rn) gas, a carcinogen, is exuded from the Earth in certain locations and trapped inside houses. Building materials including carpeting and plywood emit formaldehyde (H2CO) gas. Paint and solvents give off volatile organic compounds (VOCs) as they dry. Lead paint can degenerate into dust and be inhaled. Intentional air pollution is introduced with the use of air fresheners, incense, and other scented items. Controlled wood fires in stoves and fireplaces can add significant amounts of smoke particulates into the air, inside and out. Indoor pollution fatalities may be caused by using pesticides and other chemical sprays indoors without proper ventilation. Carbon monoxide (CO) poisoning and fatalities are often caused by faulty vents and chimneys, or by the burning of charcoal indoors. Chronic carbon monoxide poisoning can result even from poorly adjusted pilot lights. Traps are built into all domestic plumbing to keep sewer gas, hydrogen sulfide, out of interiors. Clothing emits tetrachloroethylene, or other dry cleaning fluids, for days after dry cleaning. Though its use has now been banned in many countries, the extensive use of asbestos in industrial and domestic environments in the past has left a potentially very dangerous material in many localities. Asbestosis is a chronic inflammatory medical condition affecting the tissue of the lungs. It occurs after long-term, heavy exposure to asbestos from asbestos-containing materials in structures. Sufferers have severe dyspnea (shortness of breath) and are at an increased risk regarding several different types of lung cancer. As clear explanations are not always stressed in non-technical literature, care should be taken to distinguish between several forms of relevant diseases. According to the World Health Organisation (WHO), these may defined as; asbestosis, lung cancer, and mesothelioma (generally a very rare form of cancer, when more widespread it is almost always associated with prolonged exposure to asbestos).

Biological sources of air pollution are also found indoors, as gases and airborne particulates. Pets produce dander, people produce dust from minute skin flakes and decomposed hair, dust mites in bedding, carpeting and furniture produce enzymes and micrometre-sized fecal droppings, inhabitants emit methane, mold forms in walls and generates mycotoxins and spores, air conditioning systems can incubate Legionnaires' disease and mold, and houseplants, soil and surrounding gardens can produce pollen, dust, and mold. Indoors, the lack of air circulation allows these airborne pollutants to accumulate more than they would otherwise occur in nature.

Health effects The World Health Organization states that 2.4 million people die each year from causes directly attributable to air pollution, with 1.5 million of these deaths attributable to indoor air pollution. "Epidemiological studies suggest that more than 500,000 Americans die each year from cardiopulmonary disease linked to breathing fine particle air pollution. . ." A study by the University of Birmingham has shown a strong correlation between pneumonia related deaths and air pollution from motor vehicles. Worldwide more deaths per year are linked to air pollution than to automobile accidents. Published in 2005 suggests that 310,000 Europeans die from air pollution annually. Causes of deaths include aggravated asthma, emphysema, lung and heart diseases, and respiratory allergies. The US EPA estimates that a proposed set of changes in diesel engine technology (Tier 2) could result in 12,000 fewer premature mortalities, 15,000 fewer heart attacks, 6,000 fewer emergency room visits by children with asthma, and 8,900 fewer respiratory-related hospital admissions each year in the United States. The worst short term civilian pollution crisis in India was the 1984 Bhopal Disaster. Leaked industrial vapors from the Union Carbide factory, belonging to Union Carbide, Inc., U.S.A., killed more than 25,000 people outright and injured anywhere from 150,000 to 600,000. The United Kingdom suffered its worst air pollution event when the December 4 Great Smog of 1952 formed over London. In six days more than 4,000 died, and 8,000 more died within the following months. An accidental leak of anthrax spores from a biological warfare laboratory in the former USSR in 1979 near Sverdlovsk is believed to have been the cause of hundreds of civilian deaths. The worst single incident of air pollution to occur in the United States of America occurred in Donora, Pennsylvania in late October, 1948, when 20 people died and over 7,000 were injured. The health effects caused by air pollutants may include difficulty in breathing, wheezing, coughing and aggravation of existing respiratory and cardiac conditions. These effects can result in increased medication use, increased doctor or emergency room visits, more hospital admissions and premature death. The human health effects of poor air quality are far reaching, but principally affect the body's respiratory system and the cardiovascular system. Individual reactions to air pollutants depend on the type of pollutant a person is exposed to, the degree of exposure, the individual's health status and genetics. A new economic study of the health impacts and associated costs of air pollution in the Los Angeles Basin and San Joaquin Valley of Southern California shows that more than

3800 people die prematurely (approximately 14 years earlier than normal) each year because air pollution levels violate federal standards. The number of annual premature deaths is considerably higher than the fatalities related to auto collisions in the same area, which average fewer than 2,000 per year. Diesel exhaust (DE) is a major contributor to combustion derived particulate matter air pollution. In several human experimental studies, using a well validated exposure chamber setup, DE has been linked to acute vascular dysfunction and increased thrombus formation. This serves as a plausible mechanistic link between the previously described association between particulate matter air pollution and increased cardiovascular morbidity and mortality.

Effects on cystic fibrosis A study from around the years of 1999 to 2000, by the University of Washington, showed that patients near and around particulate matter air pollution had an increased risk of pulmonary exacerbations and decrease in lung function. Patients were examined before the study for amounts of specific pollutants like Pseudomonas aeruginosa or Burkholderia cenocepacia as well as their socioeconomic standing. Participants involved in the study were located in the United States in close proximity to an Environmental Protection Agency. During the time of the study 117 deaths were associated with air pollution. Many patients in the study lived in or near large metropolitan areas in order to be close to medical help. These same patients had higher level of pollutants found in their system because of more emissions in larger cities. As cystic fibrosis patients already suffer from decreased lung function, everyday pollutants such as smoke, emissions from automobiles, tobacco smoke and improper use of indoor heating devices could further compromise lung function.

Effects on COPD Chronic obstructive pulmonary disease (COPD) includes diseases such as chronic bronchitis, emphysema, and some forms of asthma. A study conducted in 1960-1961 in the wake of the Great Smog of 1952 compared 293 London residents with 477 residents of Gloucester, Peterborough, and Norwich, three towns with low reported death rates from chronic bronchitis. All subjects were male postal truck drivers aged 40 to 59. Compared to the subjects from the outlying towns, the London subjects exhibited more severe respiratory symptoms (including cough, phlegm, and dyspnea), reduced lung function (FEV1 and peak flow rate), and increased sputum production and purulence. The differences were more pronounced for subjects aged 50 to 59. The study controlled for age and smoking habits, so concluded that air pollution was the most likely cause of the observed differences. It is believed that much like cystic fibrosis, by living in a more urban environment serious health hazards become more apparent. Studies have shown that in urban areas patients

suffer mucus hypersecretion, lower levels of lung function, and more self diagnosis of chronic bronchitis and emphysema.

Effects on children Cities around the world with high exposure to air pollutants have the possibility of children living within them to develop asthma, pneumonia and other lower respiratory infections as well as a low initial birth rate. Protective measures to ensure the youths' health are being taken in cities such as New Delhi, India where buses now use compressed natural gas to help eliminate the “pea-soup” smog. Research by the World Health Organization shows there is the greatest concentration of particulate matter particles in countries with low economic world power and high poverty and population rates. Examples of these countries include Egypt, Sudan, Mongolia, and Indonesia. In the United States, the Clean Air Act was passed in 1970, however in 2002 at least 146 million Americans were living in non-attainment areas—regions in which the concentration of certain air pollutants exceeded federal standards. Those pollutants are known as the criteria pollutants, and include ozone, particulate matter, sulfur dioxide, nitrogen dioxide, carbon monoxide, and lead. Because children are outdoors more and have higher minute ventilation they are more susceptible to the dangers of air pollution.

Health effects in relatively "clean" areas Even in areas with relatively low levels of air pollution, public health effects can be substantial and costly. This is because effects can occur at very low levels and a large number of people can potentially breathe in such pollutants. A 2005 scientific study for the British Columbia Lung Association showed that a 1% improvement in ambient PM2.5 and ozone concentrations will produce a $29 million in annual savings in the region in 2010. This finding is based on health valuation of lethal (mortality) and sublethal (morbidity) effects.

Reduction efforts There are various air pollution control technologies and land use planning strategies available to reduce air pollution. At its most basic level land use planning is likely to involve zoning and transport infrastructure planning. In most developed countries, land use planning is an important part of social policy, ensuring that land is used efficiently for the benefit of the wider economy and population as well as to protect the environment. Efforts to reduce pollution from mobile sources includes primary regulation (many developing countries have permissive regulations), expanding regulation to new sources (such as cruise and transport ships, farm equipment, and small gas-powered equipment such as lawn trimmers, chainsaws, and snowmobiles), increased fuel efficiency (such as through the use of hybrid vehicles), conversion to cleaner fuels (such as bioethanol, biodiesel, or conversion to electric vehicles).

Control devices The following items are commonly used as pollution control devices by industry or transportation devices. They can either destroy contaminants or remove them from an exhaust stream before it is emitted into the atmosphere. •

Particulate control o Mechanical collectors (dust cyclones, multicyclones) o Electrostatic precipitators An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream. o Baghouses Designed to handle heavy dust loads, a dust collector consists of a blower, dust filter, a filter-cleaning system, and a dust receptacle or dust removal system (distinguished from air cleaners which utilize disposable filters to remove the dust). o

Particulate scrubbersWet scrubber is a form of pollution control technology. The term describes a variety of devices that use pollutants from a furnace flue gas or from other gas streams. In a wet scrubber, the polluted gas stream is brought into contact with the scrubbing liquid, by spraying it with the liquid, by forcing it through a pool of liquid, or by some other contact method, so as to remove the pollutants.

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Scrubbers o Baffle spray scrubber o Cyclonic spray scrubber o Ejector venturi scrubber o Mechanically aided scrubber o Spray tower o Wet scrubber

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NOx control o Low NOx burners o Selective catalytic reduction (SCR) o Selective non-catalytic reduction (SNCR) o NOx scrubbers o Exhaust gas recirculation o Catalytic converter (also for VOC control)

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VOC abatement o Adsorption systems, such as activated carbon o Flares

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Thermal oxidizers Catalytic oxidizers Biofilters Absorption (scrubbing) Cryogenic condensers Vapor recovery systems

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Acid Gas/SO2 control o Wet scrubbers o Dry scrubbers o Flue gas desulfurization

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Mercury control o Sorbent Injection Technology o Electro-Catalytic Oxidation (ECO) o K-Fuel

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Dioxin and furan control

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Miscellaneous associated equipment o Source capturing systems o Continuous emissions monitoring systems (CEMS)

Legal regulations

Smog in Cairo In general, there are two types of air quality standards. The first class of standards (such as the U.S. National Ambient Air Quality Standards) set maximum atmospheric concentrations for specific pollutants. Environmental agencies enact regulations which are intended to result in attainment of these target levels. The second class (such as the North American Air Quality Index) take the form of a scale with various thresholds, which is used to communicate to the public the relative risk of outdoor activity. The scale may or may not distinguish between different pollutants.

Cities Air pollution is usually concentrated in densely populated metropolitan areas, especially in developing countries where environmental regulations are relatively lax or nonexistent. However, even populated areas in developed countries attain unhealthy levels of pollution.

Carbon dioxide emissions Most Polluted World Cities by PM Particulate matter, City μg/m³ (2004) 169 Cairo, Egypt 150 Delhi, India 128 Kolkata, India (Calcutta) 125 Tianjin, China 123 Chongqing, China 109 Kanpur, India 109 Lucknow, India 104 Jakarta, Indonesia 101 Shenyang, China Total CO2 emissions Countries with the highest CO2 emissions Carbon dioxide emissions per Percentage of global total Country year (106 Tons) (2006) 6,103 21.5% China United States 5,752 20.2% 1,564 5.5% Russia 1,510 5.3% India 1293 4.6% Japan Germany 805 2.8% United Kingdom 568 2.0% Canada 544 1.9% 475 1.7% South Korea 474 1.7% Italy

Per capita CO2 emissions Countries with the highest per capita CO2 emissions Carbon dioxide emissions per year Country (Tons per person) (2006) Qatar 56.2 United Arab Emirates 32.8 Kuwait 31.2 Bahrain 28.8 Trinidad and Tobago 25.3 Luxembourg 24.5 Netherlands Antilles 22.8 22.3 Aruba United States 19 Australia 18.1

Atmospheric dispersion The basic technology for analyzing air pollution is through the use of a variety of mathematical models for predicting the transport of air pollutants in the lower atmosphere. The principal methodologies are: • • • •

Point source dispersion, used for industrial sources. Line source dispersion, used for airport and roadway air dispersion modeling Area source dispersion, used for forest fires or duststorms Photochemical models, used to analyze reactive pollutants that form smog

Visualization of a buoyant Gaussian air pollution dispersion plume as used in many atmospheric dispersion models

The point source problem is the best understood, since it involves simpler mathematics and has been studied for a long period of time, dating back to about the year 1900. It uses a Gaussian dispersion model for buoyant pollution plumes to forecast the air pollution isopleths, with consideration given to wind velocity, stack height, emission rate and stability class (a measure of atmospheric turbulence). This model has been extensively validated and calibrated with experimental data for all sorts of atmospheric conditions. The roadway air dispersion model was developed starting in the late 1950s and early 1960s in response to requirements of the National Environmental Policy Act and the U.S. Department of Transportation (then known as the Federal Highway Administration) to understand impacts of proposed new highways upon air quality, especially in urban areas. Several research groups were active in this model development, among which were: the Environmental Research and Technology (ERT) group in Lexington, Massachusetts, the ESL Inc. group in Sunnyvale, California and the California Air Resources Board group in Sacramento, California. The research of the ESL group received a boost with a contract award from the United States Environmental Protection Agency to validate a line source model using sulfur hexafluoride as a tracer gas. This program was successful in validating the line source model developed by ESL inc. Some of the earliest uses of the model were in court cases involving highway air pollution, the Arlington, Virginia portion of Interstate 66 and the New Jersey Turnpike widening project through East Brunswick, New Jersey. Area source models were developed in 1971 through 1974 by the ERT and ESL groups, but addressed a smaller fraction of total air pollution emissions, so that their use and need was not as widespread as the line source model, which enjoyed hundreds of different applications as early as the 1970s. Similarly photochemical models were developed primarily in the 1960s and 1970s, but their use was more specialized and for regional needs, such as understanding smog formation in Los Angeles, California.

Environmental impacts of greenhouse gas pollutants The greenhouse effect is a phenomenon whereby greenhouse gases create a condition in the upper atmosphere causing a trapping of heat and leading to increased surface and lower tropospheric temperatures. Carbon dioxide from combustion of fossil fuels is the major problem. Other greenhouse gases include methane, hydrofluorocarbons, perfluorocarbons, chlorofluorocarbons, nitrogen oxides, and ozone. This effect has been understood by scientists for about a century, and technological advancements during this period have helped increase the breadth and depth of data relating to the phenomenon. Currently, scientists are studying the role of changes in composition of greenhouse gases from natural and anthropogenic sources for the effect on climate change. A number of studies have also investigated the potential for long-term rising levels of atmospheric carbon dioxide to cause increases in the acidity of ocean waters and the possible effects of this on marine ecosystems.

Chapter- 9

Oil Spill

Deepwater Horizon oil spill on June 25, 2010.

A squid after an oil spill

Oil Sick from the Montara oil spill in the Timor Sea, September, 2009. An oil spill is a release of a liquid petroleum hydrocarbon into the environment due to human activity, and is a form of pollution. The term often refers to marine oil spills, where oil is released into the ocean or coastal waters. Oil spills include releases of crude oil from tankers, offshore platforms, drilling rigs and wells, as well as spills of refined petroleum products (such as gasoline, diesel) and their by-products, and heavier fuels used by large ships such as bunker fuel, or the spill of any oily white substance refuse or waste oil. Spills may take months or even years to clean up. Oil also enters the marine environment from natural oil seeps. Public attention and regulation has tended to focus most sharply on seagoing oil tankers.

Environmental effects

Surf Scoter covered in oil as a result of the 2007 San Francisco Bay oil spill. Less than 1% of oil soaked birds survive, even after cleaning. The oil penetrates into the structure of the plumage of birds, reducing its insulating ability, thus making the birds more vulnerable to temperature fluctuations and much less buoyant in the water. It also impairs birds' flight abilities to forage and escape from predators. As they attempt to preen, birds typically ingest oil that covers their feathers, causing kidney damage, altered liver function, and digestive tract irritation. This and the limited foraging ability quickly causes dehydration and metabolic imbalances. Hormonal balance alteration including changes in luteinizing protein can also result in some birds exposed to petroleum. Most birds affected by an oil spill die unless there is human intervention. Marine mammals exposed to oil spills are affected in similar ways as seabirds. Oil coats the fur of Sea otters and seals, reducing its insulation abilities and leading to body temperature

fluctuations and hypothermia. Ingestion of the oil causes dehydration and impaired digestions. Because oil floats on top of water, less sunlight penetrates into the water, limiting the photosynthesis of marine plants and phytoplankton. This, as well as decreasing the fauna populations, affects the food chain in the ecosystem. There are three kinds of oil-consuming bacteria. Sulfate-reducing bacteria (SRB) and acid-producing bacteria are anaerobic, while general aerobic bacteria (GAB) are aerobic. These bacteria occur naturally and will act to remove oil from an ecosystem, and their biomass will tend to replace other populations in the food chain.

Cleanup and recovery

Clean-up efforts after the Exxon Valdez oil spill.

A US Navy oil spill response team drills with a "Harbour Buster high-speed oil containment system". Cleanup and recovery from an oil spill is difficult and depends upon many factors, including the type of oil spilled, the temperature of the water (affecting evaporation and biodegradation), and the types of shorelines and beaches involved. Methods for cleaning up include: • •

Bioremediation: use of microorganisms or biological agents to break down or remove oil. Bioremediation Accelerator: Oleophilic, hydrophobic chemical, containing no bacteria, which chemically and physically bonds to both soluble and insoluble hydrocarbons. The bioremedation accelerator acts as a herding agent in water and on the surface, floating molecules to the surface of the water, including solubles such as phenols and BTEX, forming gel-like agglomerations. Undetectable levels of hydrocarbons can be obtained in produced water and manageable water columns. By overspraying sheen with bioremediation accelerator, sheen is eliminated within minutes. Whether applied on land or on water, the nutrient-rich emulsion creates a bloom of local, indigenous, pre-existing, hydrocarbonconsuming bacteria. Those specific bacteria break down the hydrocarbons into water and carbon dioxide, with EPA tests showing 98% of alkanes biodegraded in 28 days; and aromatics being biodegraded 200 times faster than in nature they

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also sometimes use the hydrofireboom to clean the oil up by taking it away from most of the oil and burning it. Controlled burning can effectively reduce the amount of oil in water, if done properly. But it can only be done in low wind, and can cause air pollution.

Oil slicks on Lake Maracaibo.

Volunteers cleaning up the aftermath of the Prestige oil spill. •

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Dispersants act as detergents, clustering around oil globules and allowing them to be carried away in the water. This improves the surface aesthetically, and mobilizes the oil. Smaller oil droplets, scattered by currents, may cause less harm and may degrade more easily. But the dispersed oil droplets infiltrate into deeper water and can lethally contaminate coral. Recent research indicates that some dispersants are toxic to corals. Watch and wait: in some cases, natural attenuation of oil may be most appropriate, due to the invasive nature of facilitated methods of remediation, particularly in ecologically sensitive areas such as wetlands. Dredging: for oils dispersed with detergents and other oils denser than water. Skimming: Requires calm waters Solidifying: Solidifiers are composed of dry hydrophobic polymers that both adsorb and absorb. They clean up oil spills by changing the physical state of spilled oil from liquid to a semi-solid or a rubber-like material that floats on water. Solidifiers are insoluble in water, therefore the removal of the solidified oil is easy and the oil will not leach out. Solidifiers have been proven to be relatively non-toxic to aquatic and wild life and have been proven to suppress harmful vapors commonly associated with hydrocarbons such as Benzene, Xylene, Methyl Ethyl, Acetone and Naphtha. The reaction time for solidification of oil is controlled by the surf area or size of the polymer as well as the viscosity of the oil. Some solidifier product manufactures claim the solidified oil can be disposed of in landfills, recycled as an additive in asphalt or rubber products, or burned as a low ash fuel. A solidifier called C.I.Agent (manufactured by C.I.Agent Solutions of Louisville, Kentucky) is being used by BP in granular form as well as in Marine and Sheen Booms on Dauphin Island, AL and Fort Morgan, MS to aid in the Deepwater Horizon oil spill cleanup. Vacuum and centrifuge: oil can be sucked up along with the water, and then a centrifuge can be used to separate the oil from the water - allowing a tanker to be filled with near pure oil. Usually, the water is returned to the sea, making the process more efficient, but allowing small amounts of oil to go back as well. This issue has hampered the use of centrifuges due to a United States regulation limiting the amount of oil in water returned to the sea.

Equipment used includes: • • • • • •

Booms: large floating barriers that round up oil and lift the oil off the water Skimmers: skim the oil Sorbents: large absorbents that absorb oil Chemical and biological agents: helps to break down the oil Vacuums: remove oil from beaches and water surface Shovels and other road equipments: typically used to clean up oil on beaches

Prevention •

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Seafood Sensory Training- in an effort to detect oil in seafood, inspectors and regulators are being trained to sniff out seafood tainted by oil and make sure the product reaching consumers is safe to eat. Secondary containment - methods to prevent releases of oil or hydrocarbons into environment. Oil Spill Prevention Containment and Countermeasures (SPCC) program by the United States Environmental Protection Agency. Double-hulling - build double hulls into vessels, which reduces the risk and severity of a spill in case of a collision or grounding. Existing single-hull vessels can also be rebuilt to have a double hull.

Environmental Sensitivity Index (ESI) mapping Environmental Sensitivity Index (ESI) maps are used to identify sensitive shoreline resources prior to an oil spill event in order to set priorities for protection and plan cleanup strategies. By planning spill response ahead of time, the impact on the environment can be minimized or prevented. Environmental sensitivity index maps are basically made up of information within the following three categories: shoreline type, and biological and human-use resources.

Shoreline type Shoreline type is classified by rank depending on how easy the garet would be to cleanup, how long the oil would persist, and how sensitive the shoreline is. The floating oil slicks put the shoreline at particular risk when they eventually come ashore, covering the substrate with oil. The differing substrates between shoreline types vary in their response to oiling, and influence the type of cleanup that will be required to effectively decontaminate the shoreline. In 1995, the US National Oceanic and Atmospheric Administration extended ESI maps to lakes, rivers, and estuary shoreline types. The exposure the shoreline has to wave energy and tides, substrate type, and slope of the shoreline are also taken into account – in addition to biological productivity and sensitivity. The productivity of the shoreline habitat is also taken into account when determining ESI ranking. Mangroves and marshes tend to have higher ESI rankings due to the potentially long-lasting and damaging effects of both the oil contamination and cleanup actions. Impermeable and exposed surfaces with high wave action are ranked

lower due to the reflecting waves keeping oil from coming onshore, and the speed at which natural processes will remove the oil.

Biological resources Habitats of plants and animals that may be at risk from oil spills are referred to as “elements” and are divided by functional group. Further classification divides each element into species groups with similar life histories and behaviors relative to their vulnerability to oil spills. There are eight element groups: Birds, Reptiles Amphibians, Fish, Invertebrates, Habitats and Plants, Wetlands, and Marine Mammals and Terrestrial Mammals. Element groups are further divided into sub-groups, for example, the ‘marine mammals’ element group is divided into dolphins, manatees, pinnipeds (seals, sea lions & walruses), polar bears, sea otters and whales. Issues taken into consideration when ranking biological resources include the observance of a large number of individuals in a small area, whether special life stages occur ashore (nesting or molting), and whether there are species present that are threatened, endangered or rare.

Human-use resources Human use resources are divided into four major classifications; archaeological importance or cultural resource site, high-use recreational areas or shoreline access points, important protected management areas, or resource origins. Some examples include airports, diving sites, popular beach sites, marinas, natural reserves or marine sanctuaries.

Estimating the volume of a spill By observing the thickness of the film of oil and its appearance on the surface of the water, it is possible to estimate the quantity of oil spilled. If the surface area of the spill is also known, the total volume of the oil can be calculated. Film thickness

Quantity spread nm gal/sq mi L/ha

Appearance in mm Barely 0.0000015 0.0000380 38 visible Silvery 0.0000030 0.0000760 76 sheen First trace of 0.0000060 0.0001500 150 color Bright bands 0.0000120 0.0003000 300 of color Colors begin 0.0000400 0.0010000 1000 to dull

25

0.370

50

0.730

100

1.500

200

2.900

666

9.700

Colors are 0.0000800 0.0020000 2000 much darker

1332

19.500

Oil spill model systems are used by industry and government to assist in planning and emergency decision making. Of critical importance for the skill of the oil spill model prediction is the adequate description of the wind and current fields. There is a worldwide oil spill modelling (WOSM) program. Tracking the scope of an oil spill may also involve verifying that hydrocarbons collected during an ongoing spill are derived from the active spill or some other source. This can involve sophisticated analytical chemistry focused on finger printing an oil source based on the complex mixture of substances present. Largely, these will be various hydrocarbons, among the most useful being polyaromatic hydrocarbons. In addition, both oxygen and nitrogen heterocyclic hydrocarbons, such as parent and alkyl homologues of carbazole, quinoline, and pyridine, are present in many crude oils. As a result, these compounds have great potential to supplement the existing suite of hydrocarbons targets to fine tune source tracking of petroleum spills. Such analysis can also be used to follow weathering and degradation of crude spills.

Largest oil spills Oil spills of over 100,000 tons or 30 million US gallons, ordered by tons[a] Spill / *Tons of US Location Date Barrels Tanker crude oil Gallons January, 1,000,000 42,000,00 Kuwaiti 1991 136,000,000- ,0000,000Kuwait oil fires [b] November, 205,000,000 1,500,000 63,000,00 1991 ,000 0,000 January, 25,000,00 1,050,000, 1991 3,409,000- 0000Kuwaiti Kuwait November, 6,818,000 50,000,00 2,100,000, oil lakes [c] 1991 0 000 United May 14, Lakeview States, Kern 1910 – 378,000,0 1,200,000 9,000,000 Gusher County, September, 00 California 1911 January 19, 1991 January 28, 1991 April 20, United 2010 – Deepwater States, Gulf of July 15, Horizon Mexico 2010 Mexico, June 3, Ixtoc I Iraq, Gulf War Persian Gulf oil spill [d] and Kuwait

818,000– 1,091,000

560,000585,000 454,000–

252,000,0 6,000,000 00– – 336,000,0 8,000,000 00 172,000,0 4,100,000 00180,000,0 4,300,000 00 3,329,000 139,818,0

Gulf of Mexico

1979 – 480,000 March 23, 1980

Atlantic Empress / Trinidad July 19, and Tobago 1979 Aegean Captain Fergana Uzbekista March 2, n 1992 Valley Nowruz Iran, February Field Persian Gulf 4, 1983 Platform Angola, 700 nmi May 28, ABT (1,300 km; 1991 Summer 810 mi) offshore South August 6, Castillo de Africa, 1983 Bellver Saldanha Bay Amoco France, March 16, 1978 Cadiz Brittany Italy, Mediterranean April 11, MT Haven 1991 Sea near Genoa Canada, 700 nmi November Odyssey (1,300 km; 10, 1988 810 mi) off Nova Scotia Iran, Gulf December Sea Star of Oman 19, 1972 Irenes Greece, February 23, 1980 Serenade Pylos Spain, A May 12, Urquiola 1976 Coruña Torrey Canyon

287,000

2,105,000

88,396,00 0

285,000

2,090,000

87,780,00 0

260,000

1,907,000

80,080,00 0

260,000

1,907,000

80,080,00 0

252,000

1,848,000

77,616,00 0

223,000

1,635,000

68,684,00 0

144,000

1,056,000

44,352,00 0

132,000

968,000

40,656,00 0

115,000 100,000 100,000

United March 18, 80,000– Kingdom, 1967 119,000 Isles of Scilly

Greenpoint United oil spill States,

1940 – 1950s

– 00– 3,520,000 147,840,0 00

55,000– 97,000

35,420,00 0 30,800,00 733,000 0 30,800,00 733,000 0 24,654,00 587,000– 0– 873,000 36,666,00 0 400,000– 17,000,00 710,000 0– 843,000

Brooklyn, New York City a

30,000,00 0

One ton of crude oil is roughly equal to 308 US gallons or 7.33 barrels approx.; 1 oil barrel is equal to 35 imperial or 42 US gallons. b Estimates for the amount of oil burned in the Kuwaiti oil fires range from 500,000,000 barrels (79,000,000 m3) to nearly 2,000,000,000 barrels (320,000,000 m3). 732 wells were set ablaze, while many others were severely damaged and gushed uncontrolled for several months. The fires alone were estimated to consume approximately 6,000,000 barrels (950,000 m3) of oil per day at their peak. However, it is difficult to find reliable sources for the total amount of oil burned. The range of 1,000,000,000 barrels (160,000,000 m3) to 1,500,000,000 barrels (240,000,000 m3) given here represents frequently-cited figures, but better sources are needed. c Oil spilled from sabotaged fields in Kuwait during the 1991 Persian Gulf War pooled in approximately 300 oil lakes, estimated by the Kuwaiti Oil Minister to contain approximately 25,000,000 to 50,000,000 barrels (7,900,000 m3) of oil. According to the U.S. Geological Survey, this figure does not include the amount of oil absorbed by the ground, forming a layer of "tarcrete" over approximately five percent of the surface of Kuwait, fifty times the area occupied by the oil lakes. d Estimates for the Gulf War oil spill range from 4,000,000 to 11,000,000 barrels (1,700,000 m3). The figure of 6,000,000 to 8,000,000 barrels (1,300,000 m3) is the range adopted by the U.S. Environmental Protection Agency and the United Nations in the immediate aftermath of the war, 1991-1993, and is still current, as cited by NOAA and The New York Times in 2010. This amount only includes oil discharged directly into the Persian Gulf by the retreating Iraqi forces from January 19 to 28, 1991. However, according to the U.N. report, oil from other sources not included in the official estimates continued to pour into the Persian Gulf through June, 1991. The amount of this oil was estimated to be at least several hundred thousand barrels, and may have factored into the estimates above 8,000,000 barrels (1,300,000 m3).

Chapter- 10

Environmental Effects of Wind Power

Livestock ignore wind turbines, and continue to graze as they did before wind turbines were installed. A European Commission report has found wind to have the lowest external costs, comprising human health impacts, building and crop damage, global warming, loss of amenities and ecological impact, when compared to coal, oil, gas, biomass, nuclear, hydro and photovoltaic electricity generation.

Energy derived from wind power consumes no fuel, and emits no air pollution. A study by Lenzen and Munksgaard of the University of Sydney and the Danish Institute for Local Governmental Studies finds that the energy consumed in manufacturing and transporting the materials used to build a wind power plant is paid back within months. Mark Diesendorf, Director of Sustainability Centre, states that wind installations in agricultural areas take very little land and are compatible with grazing and crops. There are reports of bird and bat mortality at wind turbines, as there are around other artificial structures. The scale of the ecological impact may or may not be significant, depending on the particular site. Prevention and mitigation of wildlife fatalities, and protection of peat bogs, affect the siting and operation of wind turbines. There are conflicting reports about the effects of noise on people who live very close to a wind turbine.

Carbon dioxide emissions and pollution Wind power consumes no fuel for continuing operation, and has no emissions directly related to electricity production. Wind turbines produce no carbon dioxide, sulfur dioxide, mercury, particulates, or any other type of air pollution, as do fossil fuel power sources. Wind power plants consume resources in manufacturing and construction. During manufacture of the wind turbine, steel, concrete, aluminum and other materials will have to be made and transported using energy-intensive processes, generally using fossil energy sources. The wind turbine manufacturer Vestas claims that initial carbon dioxide emissions "pay back" is within about 9 months of operation for off shore turbines. A 2006 study found the CO2 emissions of wind power to range from 14 to 33 tonnes per GWh of energy produced. Most of the CO2 emission comes from producing the concrete for wind-turbine foundations. A study by the Irish national grid stated that "Producing electricity from wind reduces the consumption of fossil fuels and therefore leads to emissions savings", and found reductions in CO2 emissions ranging from 0.33 to 0.59 tonnes of CO2 per MWh. The UKERC study of intermittency also states that wind energy can displace fossil fuelbased generation, reducing both fuel use and carbon dioxide emissions.

Net energy gain The initial carbon dioxide emission from energy used in the installation is "paid back" within about 9 months of operation for off shore turbines. Any practical large-scale energy source must replace the energy used in its construction. The energy return on investment (EROI) for wind energy is equal to the cumulative electricity generated

divided by the cumulative primary energy required to build and maintain a turbine. The EROI for wind ranges from 5 to 35, with an average of around 18, according to windenergy advocates. EROI is strongly proportional to turbine size, and larger lategeneration turbines are at the high end of this range, at or above 35. Since energy produced is several times energy consumed in construction, there is a net energy gain.

Ecology Land use

Wind farm near an open-pit coal mine in Germany. Wind farms are often built on or near land that has already been impacted by land clearing.

In the United States, landowners typically receive $3,000 to $5,000 per year in rental income from each wind turbine, while farmers continue to grow crops or graze cattle up to the foot of the turbines.

A wind turbine at Greenpark, Reading, England, producing electricity for around one thousand homes Wind farms are often built on land that has already been impacted by land clearing. The vegetation clearing and ground disturbance required for wind farms is minimal compared with coal mines and coal-fired power stations. If wind farms are decommissioned, the landscape can be returned to its previous condition. Farmers and graziers often lease land to companies building wind farms. In the U.S., farmers may receive annual lease payments of two thousand to five thousand dollars per

turbine. The land can still be used for farming and cattle grazing. Livestock are unaffected by the presence of wind farms. International experience shows that livestock will "graze right up to the base of wind turbines and often use them as rubbing posts or for shade". Wind-energy advocates contend that less than 1% of the land would be used for foundations and access roads, the other 99% could still be used for farming. Critics point out that the clearing of trees around tower bases may be necessary for installation sites on mountain ridges, such as in the northeastern U.S. Turbines are not generally installed in urban areas. Buildings interfere with wind, turbines must be sited a safe distance ("setback") from residences in case of failure, and the value of land is high. However, there are a few notable exceptions. Toronto Hydro has built a lake shore demonstration project, and Steel Winds is a 20 MW urban project south of Buffalo, New York. Both of these projects are in urban locations, but benefit from being on uninhabited lake shore property. In the UK there has also been concern about the damage caused to peat bogs, with one Scottish MEP campaigning for a moratorium on wind developments on peatlands saying that "Damaging the peat causes the release of more carbon dioxide than wind farms save". Offshore locations use no land and avoid known shipping channels.

Impact on wildlife Environmental assessments are routinely carried out for wind farm proposals, and potential impacts on the local environment (eg plants, animals, soils) are evaluated. Turbine locations and operations are often modified as part of the approval process to avoid or minimise impacts on threatened species and their habitats. Any unavoidable impacts can be offset with conservation improvements of similar ecosystems which are unaffected by the proposal. Projects such as the Black Law Wind Farm have received wide recognition for its contribution to environmental objectives, including praise from the Royal Society for the Protection of Birds, who said that the scheme was not only improving the landscape in a derelict opencast mining site, but also benefiting a range of wildlife in the area, with an extensive habitat management projects covering over 14 square kilometres.

Birds Danger to birds is often the main complaint against the installation of a wind turbine. However, a study estimates that wind farms are responsible for 0.3 to 0.4 fatalities per gigawatt-hour (GWh) of electricity while fossil-fueled power stations are responsible for about 5.2 fatalities per GWh. The author's study therefore claims that fossil fuel based electricity causes about 10 times more fatalities than wind farm based electricity,

primarily due to habitat alteration from pollution and mountain-top removal. The number of birds killed by wind turbines is also negligible when compared to the number that die as a result of other human activities such as traffic, hunting, electric power transmission and high-rise buildings, and the introduction of feral and roaming domestic cats,. For example in Denmark, where wind turbines generate 9% of electricity, wind turbines kill about 30,000 birds per year - while cars kill 1 million birds per year; thus cars kill 33 times as many birds. Moreover, in the UK, where there are several hundred turbines, about one bird is killed per turbine per year; 10 million per year are killed by cars alone. In the United States, turbines kill 70,000 birds per year, compared to 80,000 killed by aircraft, 57 million killed by cars, 97.5 million killed by collisions with plate glass, and hundreds of millions killed by cats. An article in Nature stated that each wind turbine kills an average of 4.27 birds per year. In the UK, the Royal Society for the Protection of Birds (RSPB) concluded that "The available evidence suggests that appropriately positioned wind farms do not pose a significant hazard for birds." It notes that climate change poses a much more significant threat to wildlife, and therefore supports wind farms and other forms of renewable energy. In 2009, however, the RSPB warned that "numbers of several breeding birds of high conservation concern are reduced close to wind turbines," probably because "birds may use areas close to the turbines less often than would be expected, potentially reducing the carrying capacity of an area." The National Audubon Society in the U.S. takes a similar position, broadly supporting wind power to help mitigate global warming, while cautioning against siting wind farms in areas especially important to birds and other affected wildlife. The Peñascal Wind Power Project in Texas is located in the middle of a major bird migration route, and the wind farm uses avian radar originally developed for NASA and the United States Air Force to detect birds as far as four miles away. If the system determines that the birds are in danger of running into the rotating blades, it shuts down the turbines. The system automatically restarts the turbines when the birds have passed. At the Altamont Pass Wind Farm in California, a settlement has been reached between the Audubon Society, Californians for Renewable Energy and NextEra Energy Resources (who operate some 5,000 turbines in the area). Nearly half of the smaller turbines will be replaced by newer, more bird-friendly models. The project is expected to be complete by 2015 and includes $2.5 million for raptor habitat restoration. Some paths of bird migration, particularly for birds that fly by night, are unknown. A study suggests that migrating birds may avoid the large turbines, at least in the low-wind non-twilight conditions studied. A Danish 2005 (Biology Letters 2005:336) study showed that radio tagged migrating birds traveled around offshore wind farms, with less than 1% of migrating birds passing an offshore wind farm in Rønde, Denmark, got close to collision, though the site was studied only during low-wind non-twilight conditions.

Bats

Savi's Pipistrelle killed by "Ravna 1 wind farm" on island Pag, Croatia Bats may be injured by direct impact with turbine blades, towers, or transmission lines. Recent research shows that bats may also be killed when suddenly passing through a low air pressure region surrounding the turbine blade tips. The numbers of bats killed by existing onshore and near-shore facilities has troubled bat enthusiasts. A study in 2004 estimated that over 2200 bats were killed by 63 onshore turbines in just six weeks at two sites in the eastern U.S. This study suggests some onshore and near-shore sites may be particularly hazardous to local bat populations and more research is needed. Migratory bat species appear to be particularly at risk, especially during key movement periods (spring and more importantly in fall). Lasiurines

such as the hoary bat, red bat, and the silver-haired bat appear to be most vulnerable at North American sites. Almost nothing is known about current populations of these species and the impact on bat numbers as a result of mortality at windpower locations. It has been suggested that bats are attracted to these structures in search of roosts. Offshore wind sites 10 km (6 mi) or more from shore do not interact with bat populations. Scientists at the U.S. Geological Survey have already conducted research using stable isotope analysis to track migration among terrestrial mammals. USGS scientists are currently applying this technique in their efforts to figure out the geographic origins of bats killed by wind turbines. In April 2009 the Bats and Wind Energy Cooperative released initial study results showing a 73% drop in bat fatalities when wind farm operations are stopped during low wind conditions, when bats are most active. Bats avoid radar transmitters, and placing microwave transmitters on wind turbine towers may reduce the number of bat collisions.

Climate change One study reports simulations that show detectable changes in global climate for very high wind farm usage, on the order of 10% of the world's land area. However, wind power has a negligible effect on global-mean surface temperature, and it would deliver "enormous global benefits by reducing emissions of CO2 and air pollutants". There may be micro-climate change due to turbulence in the wakes of the spinning turbine rotors. But more efficient rotors may significantly reduce this.

Impacts on people Safety Operation of any utility-scale energy conversion system presents safety hazards. Wind turbines do not consume fuel or produce pollution during normal operation, but still have hazards associated with their construction and operation. There have been at least 40 fatalities due to construction, operation, and maintenance of wind turbines, including both workers and members of the public, and other injuries and deaths attributed to the wind power life cycle. Most worker deaths involve falls or becoming caught in machinery while performing maintenance inside turbine housings. Blade failures and falling ice have also accounted for a number of deaths and injuries. Deaths to members of the public include a parachutist colliding with a turbine and small aircraft crashing into support structures. Other public fatalities have been blamed on collisions with transport vehicles and motorists distracted by the sight and shadow flicker of wind turbines along highways.

If a turbine's brake fails, the turbine can spin freely until it disintegrates or catches fire. Often turbine fires cannot be extinguished because of the height, and are left to burn themselves out. In the process, they generate toxic fumes and can scatter flaming debris over a wide area, starting secondary fires below. Several turbine-ignited fires have burned hundreds of acres of vegetation each, and one burned 800 square kilometres (200,000 acres) of Australian National Park. Electronic controllers and safety sub-systems monitor many different aspects of the turbine, generator, tower, and environment to determine if the turbine is operating in a safe manner within prescribed limits. These systems can temporarily shut down the turbine due to high wind, electrical load imbalance, vibration, and other problems. Recurring or significant problems cause a system lockout and notify an engineer for inspection and repair. In addition, most systems include multiple passive safety systems that stop operation even if the electronic controller fails. In his book Wind Energy Comes of Age, Paul Gipe estimated that the mortality rate for wind power from 1980–1994 was 0.4 deaths per terawatt-hour. Paul Gipe's estimate as of end 2000 was 0.15 deaths per TWh, a decline attributed to greater total cumulative generation.

Aesthetics Newer wind farms have larger, more widely spaced turbines, and have a less cluttered appearance than older installations. Wind farms are often built on land that has already been impacted by land clearing and they coexist easily with other land uses (eg grazing, crops). They also have a smaller footprint than other forms of energy generation such as coal and gas plants. However, wind farms may be close to scenic or otherwise undeveloped areas, and aesthetic issues are important for onshore and near-shore locations. Aesthetic issues are subjective and some people find wind farms pleasant and optimistic, or symbols of energy independence and local prosperity. While some tourism officials predict wind farms will damage tourism, some wind farms have themselves become tourist attractions, with several having visitor centers at ground level or even observation decks atop turbine towers. Residents near turbines may complain of "shadow flicker" on nearby residences caused by rotating turbine blades, when the sun passes behind the turbine. However, this can easily be avoided by locating the wind farm to avoid unacceptable shadow flicker, or by turning the turbine off for the few minutes of the day when the sun is at the angle that causes flicker. Wind towers require aircraft warning lights, which may create light pollution. Complaints about these lights have caused the FAA to consider allowing fewer lights per turbine in certain areas.

Noise Modern wind turbines produce significantly less noise than older designs. Turbine designers work to minimise noise, as noise reflects lost energy and output. Noise levels at nearby residences may be managed through the siting of turbines, the approvals process for wind farms, and operational management of the wind farm. Renewable UK, a wind energy trade organization, has said that the noise measured 350m from a wind farm is less than that from normal road traffic or in an office. However, some studies by physicians and acoustic engineers have reported problems from wind turbine noise, including sleep deprivation, headaches, dizziness, anxiety, and vertigo. Nina Pierpont, a New York pediatrician, has said that noise can be an important disadvantage of wind turbines, especially when building the wind turbines very close to urban environments. The controversy around Pierpont's work centers around her claims made in a self-published, non-peer-reviewed book that ultra-low frequency sounds affect human health. She asserts that wind turbines affect the mood of people and may cause physiological problems such as insomnia, headaches, tinnitus, vertigo and nausea. In December 2006, a Texas jury denied a noise pollution suit against FPL Energy, after the company demonstrated that noise readings were not excessive. The highest reading was 44 decibels, which was characterized as about the same level as a 10 mile/hour (16 km/h) wind. The nearest residence among the plaintiffs was 1,700 feet from one of the turbines. More recent lawsuits have been brought in Missouri, Pennsylvania, and Maine. In the Canadian Province of Ontario, the Ministry of the Environment created noise guidelines to limit wind turbine noise levels 30 metres away from a dwelling or campsite to 40 db(A). These regulations also set a minimum distance of 550 metres (1,804 feet) for a group of up to five relatively quiet [102 dB(A)] turbines within a 3-kilometre (1.86mile) radius, rising to 1,500 metres (4,921 feet) for a group of 11 to 25 noisier (106-107 db(A)) turbines. Larger facilities and noisier turbines would require a noise study. In a 2009 report about "Rural Wind Farms", a Standing Committe of the Parliament of New South Wales, Australia, recommended a minimum setback of two kilometres between wind turbines and neighbouring houses (which can be waived by the affected neighbour) as a precautionary approach. In July 2010, Australia's National Health and Medical Research Council reported that "there is no published scientific evidence to support adverse effects of wind turbines on health". A 2008 guest editorial in Environmental Health Perspectives' published by the National Institute of Environmental Health Sciences, the U.S. National Institutes of Health, stated: "Even seemingly clean sources of energy can have implications on human health. Wind energy will undoubtedly create noise, which increases stress, which in turn increases the risk of cardiovascular disease and cancer."

The Japanese Environment Ministry will begin a "major study into the influence of sounds of wind turbines on people's health" in April 2010, because "people living near wind power facilities are increasingly complaining of health problems". They plan a fouryear examination of all 1,517 wind turbines in the country. A 2007 report by the U.S. National Research Council noted that noise produced by wind turbines is generally not a major concern for humans beyond a half-mile or so. However, low-frequency vibration and its effects on humans are not well understood and sensitivity to such vibration resulting from wind-turbine noise is highly variable among humans. There are opposing views on this subject, and more research needs to be done on the effects of low-frequency noise on humans. Research by Stefan Oerlemans for the University of Twente and the Dutch National Aerospace Laboratory suggests that noise from existing wind turbines may be reducible by up to half by adding "saw teeth" to the trailing edges of the blades, although research is not complete.

2009 review A 2009 "expert panel review", described as being the most comprehensive to date, delved into the possible adverse health effects of those living close to wind turbines. Their report findings concluded that wind turbines do not directly make people ill. The 85-page study was sponsored by the Canadian Wind Energy Association and American Wind Energy Association. The academic and medical experts who conducted the study stated that they reached their conclusions independent of their sponsors. "We were not told to find anything," said panel expert David Colby, a public health officer in Chatham-Kent and a Professor of Medicine at the University of Western Ontario. "It was completely open ended." The study did allow that some people could be stressed out by the swishing sounds wind turbines produce. "A small minority of those exposed report annoyance and stress associated with noise perception..." [however] "Annoyance is not a disease." The study group pointed out that similar irritations are produced by local and highway vehicles, as well as from industrial operations and aircraft. The wind-industry report found, amongst other things, that: •

•

"Wind Turbine Syndrome" symptoms are the same as those seen in the general population due to stresses of daily life. They include headaches, insomnia, anxiety, dizziness, etc... low frequency and very low-frequency "infrasound" produced by wind turbines are the same as those produced by vehicular traffic and home appliances, even by the beating of people's hearts. Such 'infrasounds' are not special and convey no risk factors;

•

• •

Colby stated that evidence of harm was so minuscule that the wind associations were unable to initiate other independent collinear studies by government agencies. It was not surprising that their requests met with complete blanks on the need to examine the issues further; one study member noted: "You can't control the amount of cars going by and wind turbine noise is generally quieter than highway noise"; the power of suggestion, as conveyed by news media coverage of perceived 'wind-turbine sickness', might have triggered "anticipatory fear" in those close to turbine installations.

The study panel members included: Robert Dobie, a doctor and clinical professor at the University of Texas, Geoff Leventhall, a noise vibration and acoustics expert in the United Kingdom, Bo Sondergaard, with Danish Electronics Light and Acoustics, Michael Seilo, a professor of audiology at Western Washington University, and Robert McCunney, a biological engineering scientist at the Massachusetts Institute of Technology. McCunney contested claims that infrasounds from wind turbines could create vibrations causing ill health: "It doesn't really have much credence, at least based on the literature out there" he stated.

Offshore Many offshore wind farms are being built in UK waters. In January 2009, a comprehensive government environmental study of coastal waters in the United Kingdom concluded that there is scope for between 5,000 and 7,000 offshore wind turbines to be installed without an adverse impact on the marine environment. The study – which forms part of the Department of Energy and Climate Change's Offshore Energy Strategic Environmental Assessment – is based on more than a year's research. It included analysis of seabed geology, as well as surveys of sea birds and marine mammals.