Pollution.ppt-- For better learning University of Michigan

Editor's Notes

• #4: Air pollution can cause a variety of impacts. Greenhouse effect: described in a previous module Ozone depletion: described in a previous module Acidification: described here Smog formation: described here Eutrophication: a condition in an aquatic ecosystem where high nutrient concentrations stimulate blooms of algae (e.g., phytoplankton). Human and ecological health effects: All of the above + other toxic pollutant releases have human and ecological health effects.
• #5: Source: http://www.epa.gov/air/oaqps/takingtoxics/p1.html#1 Scientists estimate that millions of tons of toxic pollutants are released into the air each year. Most air toxics originate from manmade sources, including both mobile sources (e.g., cars, buses, trucks) and stationary sources (e.g., factories, refineries, power plants). However, some are released in major amounts from natural sources such as forest fires. Routine emissions from stationary sources constitute almost one-half of all manmade air toxics emissions.
• #6: Source: http://www.epa.gov/air/oaqps/takingtoxics/p1.html#1 There are two types of stationary sources that generate routine emissions of air toxics: "Major" sources are defined as sources that emit 10 tons per year of any of the listed toxic air pollutants, or 25 tons per year of a mixture of air toxics. Examples include chemical plants, steel mills, oil refineries, and hazardous waste incinerators. These sources may release air toxics from equipment leaks, when materials are transferred from one location to another, or during discharge through emissions stacks or vents. One key public health concern regarding major sources is the health effects on populations located downwind from them. "Area" sources consist of smaller sources, each releasing smaller amounts of toxic pollutants into the air. Area sources are defined as sources that emit less than 10 tons per year of a single air toxic, or less than 25 tons per year of a mixture of air toxics. Examples include neighborhood dry cleaners and gas stations. Though emissions from individual area sources are often relatively small, collectively their emissions can be of concern—particularly where large numbers of sources are located in heavily populated areas. EPA’s published list of "source categories" now contains 175 categories of industrial and sources that emit one or more toxic air pollutants. For each of these source categories, EPA indicated whether the sources are considered to be "major" sources or "area" sources. The 1990 Clean Air Act Amendments direct EPA to set standards requiring all major sources of air toxics (and some area sources that are of particular concern) to significantly reduce their air toxics emissions.
• #8: Source: http://www.epa.gov/oar/oaqps/greenbk/o3co.html#Ozone Nitrogen dioxide (NO2) is a brownish, highly reactive gas that is present in all urban atmospheres. NO2 can irritate the lungs, cause bronchitis and pneumonia, and lower resistance to respiratory infections. Nitrogen oxides are an important precursor both to ozone (O3) and acid rain, and may affect both terrestrial and aquatic ecosystems. The major mechanism for the formation of NO2 in the atmosphere is the oxidation of the primary air pollutant nitric oxide (NO). NOx plays a major role, together with VOCs, in the atmospheric reactions that produce O3. NOx forms when fuel is burned at high temperatures. The two major emissions sources are transportation and stationary fuel combustion sources such as electric utility and industrial boilers. Ozone (O3) is a photochemical oxidant and the major component of smog. While O3 in the upper atmosphere is beneficial to life by shielding the earth from harmful ultraviolet radiation from the sun, high concentrations of O3 at ground level are a major health and environmental concern. O3 is not emitted directly into the air but is formed through complex chemical reactions between precursor emissions of volatile organic compounds (VOC) and oxides of nitrogen (NOx) in the presence of sunlight. These reactions are stimulated by sunlight and temperature so that peak O3 levels occur typically during the warmer times of the year. Both VOCs and NOx are emitted by transportation and industrial sources. VOCs are emitted from sources as diverse as autos, chemical manufacturing, dry cleaners, paint shops and other sources using solvents. The reactivity of O3 causes health problems because it damages lung tissue, reduces lung function and sensitizes the lungs to other irritants. Carbon monoxide (CO) is a colorless, odorless and poisonous gas produced by incomplete burning of carbon in fuels. When CO enters the bloodstream, it reduces the delivery of oxygen to the body's organs and tissues. Health threats are most serious for those who suffer from cardiovascular disease, particularly those with angina or peripheral vascular disease. Exposure to elevated CO levels can cause impairment of visual perception, manual dexterity, learning ability and performance of complex tasks. 77% of the nationwide CO emissions are from transportation sources.
• #9: Source: http://www.epa.gov/oar/oaqps/greenbk/o3co.html#Ozone High concentrations of sulfur dioxide (SO2) affect breathing and may aggravate existing respiratory and cardiovascular disease. Sensitive populations include asthmatics, individuals with bronchitis or emphysema, children and the elderly. SO2 is also a primary contributor to acid deposition, or acid rain, which causes acidification of lakes and streams and can damage trees, crops, historic buildings and statues. In addition, sulfur compounds in the air contribute to visibility impairment in large parts of the country. This is especially noticeable in national parks. Ambient SO2 results largely from stationary sources such as coal and oil combustion, steel mills, refineries, pulp and paper mills and from nonferrous smelters. Particulate matter less than 2.5 microns in diameter is referred to as "fine” particles. (In comparison, a human hair is about 70 microns in diameter.) Fine particles result from many different sources including industrial and residential combustion and vehicle exhaust so their composition varies widely. Fine particles can also be formed when combustion gases are chemically transformed into particles. Particulate matter larger than 2.5 microns in diameter is referred to as coarse particles. Coarse particles have many sources, including wind-blown dust, vehicles traveling on unpaved roads, materials handling, and crushing and grinding operations. Air pollutants called particulate matter include dust, dirt, soot, smoke and liquid droplets directly emitted into the air by sources such as factories, power plants, cars, construction activity, fires and natural windblown dust. Particles formed in the atmosphere by condensation or the transformation of emitted gases such as SO2 and VOCs are also considered particulate matter. Based on studies of human populations exposed to high concentrations of particles (sometimes in the presence of SO2) and laboratory studies of animals and humans, there are major effects of concern for human health. These include effects on breathing and respiratory symptoms, aggravation of existing respiratory and cardiovascular disease, alterations in the body's defense systems against foreign materials, damage to lung tissue, carcinogenesis and premature death. The major subgroups of the populationcthat appear to be most sensitive to the effects of particulate matter include individuals with chronic obstructive pulmonary or cardiovascular disease or influenza, asthmatics, the elderly and children. Particulate matter also soils and damages materials, and is a major cause of visibility impairment in the United States. Exposure to lead (Pb) can occur through multiple pathways, including inhalation of air and ingestion of Pb in food, water, soil or dust. Excessive Pb exposure can cause seizures, mental retardation and/or behavioral disorders. A recent National Health and Nutrition Examination Survey reported a 78% decrease in blood lead levels from 12.8 to 2.8 ug/dL between 1976 and 1980 and from 1988 to 1991. This dramatic decline can be attributed to the reduction of leaded gasoline and to the removal of lead from soldered cans. Although this study shows great progress, infants and young children are especially susceptible to low doses of Pb, and this age group still shows the highest levels. Low doses of Pb can lead to central nervous system damage. Recent studies have also shown that Pb may be a factor in high blood pressure and in subsequent heart disease in middle-aged males. Lead gasoline additives, non-ferrous smelters, and battery plants are the most significant contributors to atmospheric Pb emissions. In 1993 transportation sources contributed 33% of the annual emissions, down substantially from 81% in 1985. Total Pb emissions from all sources dropped from 20,100 tons in 1985 to 4,900 tons in 1993. The decrease in Pb emissions from highway vehicles accounts for essentially all of this decline. The reasons for the decrease are noted below.
• #10: Source: NATIONAL AIR POLLUTANT EMISSION TRENDS, 1900 - 1998 United States Environmental Protection Agency Office of Air Quality Planning and Standards EPA-454/R-00-002 March 2000
• #11: Source: Latest Findings on National Air Quality: 1999 Status and Trends EPA EPA-454/F-00-002 Since the 1970 Clean Air Act was signed into law, emissions of each of the six pollutants decreased, with the exception of NOx . Between 1970 and 1999, emissions of NOx increased 17 percent. The majority of this increase can be attributed to heavy-duty diesel vehicles and coal-fired power plants. EPA has major initiatives to reduce emissions of NOx considerably from these sources. Emissions of NOx contribute to the formation of ground-level ozone (smog), acid rain, and other environmental problems, even after being carried by the wind hundreds of miles from their original source.
• #13: Between 1970 and 1999, U.S. population increased 33 percent, vehicle miles traveled increased 140 percent, and gross domestic product increased 147 percent. At the same time, total emissions of the six principal air pollutants decreased 31 percent.
• #14: EPA tracks trends in air quality based on actual measurements of pollutant concentrations in the ambient (outside) air at monitoring sites across the country. Monitoring stations are operated by state, tribal, and local government agencies as well as some federal agencies, including EPA. Trends are derived by averaging direct measurements from these monitoring stations on a yearly basis. The chart at above shows that the air quality based on concentrations of the principal pollutants has improved nationally over the last 20 years (1980–1999). The most notable improvements are seen for Pb, CO, and SO2 with 94-, 57- and 50-percent reductions, respectively.
• #15: Despite great progress in air quality improvement, approximately 62 million people nationwide still lived in counties with pollution levels above the national air quality standards in 1999. This number does not take into consideration the 8-hour ozone standard. Blue bars represent 8-hour standard for ozone.
• #16: http://www.epa.gov/airmarkets/cmap/mg_so2_before_and_aft.html This set of maps illustrates the geographic and temporal trends in state-level utility sulfur dioxide (SO2) emissions before and during implementation of Phase I of the Acid Rain Program. The maps illustrate total state-level utility SO2 emissions in 1980, 1990, and 1999. Total sulfur dioxide emissions were significantly reduced during Phase I of the Acid Rain Program. In the first five years of the program, Phase I sources reduced SO2 emissions by more than 50% from 1980 levels; total utility SO2 emissions (Phase I and II sources) were reduced almost 30% nationwide. Although most SO2 emissions occur in the Midwestern U.S., it is important to note that over time, this same region has also seen the most significant decrease in SO2 emissions in the country. The highest SO2 emitting states in 1980 (Ohio, Indiana, and Pennsylvania), have achieved an average reduction of about 40%, from 1980 levels. Acid rain causes acidification of lakes and streams and contributes to damage of trees at high elevations (for example, red spruce trees above 2,000 feet) and many sensitive forest soils. In addition, acid rain accelerates the decay of building materials and paints, including irreplaceable buildings, statues,and sculptures that are part of our nation's cultural heritage. Prior to falling to the earth, SO2 and NOx gases and their particulate matter derivatives, sulfates and nitrates, contribute to visibility degradation and harm public health.
• #17: Source: http://www.epa.gov/watertrain/agents/agents21.html Earth, as photographs taken from space clearly show, is the Water Planet. Water covers two-thirds of the planet's surface, and some of its subsurface too. It is essential to all forms of life and plays a vital role in the processes and functioning of the Earth's ecosystems. Water is the common element that links ecosystems. It links forest ecosystems of the interior mountains with the bays and estuaries along the coasts. It transports food, nutrients and other biologically important materials and organisms. It dilutes, moves and removes wastes; it cools organisms and the land, maintaining the climactic conditions that support and sustain life. Finally, water supplies energy to ecosystems because, through cooling and its motion, water saves energy that organisms and ecosystems would otherwise need to expend. People all over the planet are dependent on water to grow food, generate power, cool the machines of industry, carry wastes and much more. People use water in their personal lives for bathing and cleaning, recreating, drinking, cooking, gardening, and just for the pleasure of watching it. Water also provides habitat for fresh and salt water living resources. More than 97 percent of the Earth's water is saltwater in our oceans and salt lakes; water in icecaps/glaciers adds about 2.O percent more. Therefore, fresh water is very limited - water in lakes, streams and rivers makes up less than 0.01 percent of the Earth's water. Ground water - fresh water under the planet's surface-makes up another O.6 percent. In the United States over 250 million people depend on the freshwater in our rivers, lakes, streams and ground water supplies for their drinking water.
• #21: Sources of point and nonpoint chemical inputs to lakes, rivers, and oceans recognized by statutes. Pollutant discharges from point sources tend to be continuous and therefore relatively simple to identify and monitor. Nonpoint sources, however, arise from a suite of activities across large areas and are much more difficult to control. Issues in Ecology Number 3 Summer 1998 Nonpoint Pollution of Surface Waters with Phosphorus and Nitrogen
• #22: Source: http://www.epa.gov/watertrain/modeling/ Urban runoff The dominant characteristic of urban land areas is a high percentage of impervious land cover. Precipitation runs off directly from impervious surfaces, rather than percolating into the soil, and can often transport significant pollutant loads. A more sophisticated, yet still simple, approach to estimating pollutant loads generated by urban areas is the use of buildup-washoff models, for which there is a well-developed literature (Novotny and Olem, Water Quality: Prevention, Identification, and Management of Diffuse Pollution). This approach is based on the observation that almost all runoff from urban areas comes from the paved or impervious area, and that most of the polluting material carried in runoff accumulates within 1 meter of curbs. Thus, between precipitation events, the model estimates the buildup or amount of material that accumulates per curb length. In addition to an increase with time, buildup may be correlated with other variables such as time of year, curb height, street width, traffic speed, atmospheric deposition rate, traffic emission rate, and frequency of street cleaning. The model then estimates the amount of washoff of material that occurs in response to a precipitation event. Washoff is correlated with rainfall intensity, and the amount of available accumulated solids. Buildup-washoff calculations can be implemented with simple equations, but require additional data, including estimates of buildup rates and the intensity and inter-event timing of precipitation. The buildup-washoff formulation is also used within more complex simulation models, such as EPA's SWMM. Note that a buildup-washoff formulation is, at least in part, a representation of the actual process of pollutant load generation, rather than simply an empirical average. Such a process-based modeling technique is inherently time-variable, because it depends on the time available for buildup, and the timing and characteristics of storms which drive washoff. Non-urban runoff Non-urban sources of runoff and pollution include agriculture, forestry, and other rural land uses. Non-urban areas are generally characterized by pervious surfaces, into which water may infiltrate. Pollutant loading is often separated into a dissolved component, which moves with the flow of water, and a sediment-attached component, which moves with the erosion of sediment. A simple process-based approach is to calculate the amount of runoff volume and the amount of erosion, the apply a concentration factor to estimate pollutant loads. Overland runoff is often estimated with the Natural Resource Conservation Service (NRCS) Curve Number method (Ogrosky and Mockus, 1964). This method relates runoff volume to precipitation volume, antecedent soil moisture conditions, and a so-called "curve number" (CN). CN is taken from tables compiled by NRCS and depends on land use, land cover, and hydrologic soil group. Erosion from non-urban pervious areas is often estimated using the Universal Soil Loss Equation (USLE) or one of its modifications (Wischmeier and Smith, 1978). The USLE includes factors for rainfall erosivity, soil erodibility, slope length and steepness, and land cover and management. Depending on the units used for erosivity, the USLE may be expressed on an annual or event basis. The USLE is designed to predict long-term average rates of soil losses from fields and other land uses. The rate of soil loss is not, however, the same as the yield of eroded sediment, as a substantial amount of the eroded soil may be trapped or redeposited before reaching a water body. Therefore, in watershed models the USLE is usually coupled with an estimate of fraction of sediment delivery ("delivery ratio"). In many watersheds, delivery of dissolved nutrients via ground water flux is also significant, particularly for nitrogen. At the simple process-model level, simple mass balance models of precipitation infiltration and ground water delivery to streams are often used to account for ground water loading. Use of process-based models In an attempt to reduce uncertainty in model predictions, we have moved to process-based models, albeit simple ones. These use mathematical relationships to convert data on land use, land cover, and time series of precipitation into estimates of time series of pollutant loads to a waterbody. With a process-based model of loading in hand, we can begin to examine specific management questions, such as the following: What effects can be expected from increasing development and impervious area? How much can increased street sweeping reduce loading from urban areas? What is the effect of various agricultural and erosion control practices on sediment and nutrient loads? What areas of the watershed generate the highest loads of pollutants? It should be cautioned that even the most sophisticated process-based models of nutrient loading contain many empirical parameters which cannot be measured directly. To increase confidence in model predictions, it will be necessary to go through a process of model calibration, in which model parameters are adjusted to provide a better fit to observations.
• #23: Source: Water Quality Conditions in the United States: A Profile from the 1998 National Water Quality Inventory Report to Congress States, tribes, territories and interstate commissions report that, in 1998, about 40% of U.S. streams, lakes and estuaries that were assessed were not clean enough to support uses such as fishing and swimming. About 32% of U.S. waters were assessed for this national inventory of water quality. Leading pollutants in impaired waters include siltation, bacteria, nutrients and metals. Runoff from agricultural lands and urban areas are the primary sources of these pollutants. Although the U.S. has made significant progress in cleaning up polluted waters over the past 30 years, much remains to be done to restore and protect the Nation's waters. Findings Recent water quality data finds that more than 291,000 miles of assessed rivers and streams do not meet water quality standards. Across all types of waterbodies, states, territories, tribes and other jurisdictions report that poor water quality affects aquatic life, fish consumption, swimming, and drinking water. In their 1998 reports, states assessed 840,000 miles of rivers and 17.4 million acres of lakes, including 150,000 more river miles and 600,000 more lake acres than in their previous reports in 1996. After comparing water quality data to standards, states, tribes, and jurisdictions classify their waters into the following general categories: Attaining Water Quality Standards Good/Fully Supporting: These waters meet applicable water quality standards, both criteria and designated uses. Good/Threatened: These waters currently meet water quality standards, but water quality may degrade in the near future. Not Attaining Water Quality Standards/Impaired Fair/Partially Supporting: These waters meet waterquality standards most of the time but exhibit occasional exceedances. Poor/Not Supporting: These waters do not meet water quality standards. Water Quality Standards Not Attainable Not Attainable: The state has performed a use-attainability analysis and demonstrated that support of one or more designated uses is not attainable due to specific biological, chemical, physical, or economic/social conditions.
• #25: Bhopal 2000 people dead and 100,000 injured methyl isocyanate released from Union Carbide.
• #26: 21000 facilities were subject to TRI reporting for the 1997 reporting year
• #27: This figure illustrates on-site and off-site releases, on-site waste management activities, and transfers off-site for further waste management, reportable to TRI. Source: http://www.epa.gov/tri/tri98/pdr/chapter_1.pdf
• #30: Source: http://www.epa.gov/tri/tri98/data/datasum.htm In 1998, facilities reported a total of 7.3 billion pounds of releases to air, land, water and underground injection. The original industries reported approximately 2.4 billion pounds, or 32.6%, of the 7.3 billion pounds. Facilities in the new sectors reported almost 4.9 billion pounds, or 67.4%, of the 7.3 billion pounds. On-site releases were 93.9 % (6.9 billion pounds) of the total releases in 1998. Of these on-site releases, 62.8 % were to land, 29.9 % were to air, 3.9 % were to underground injection, and 3.4 % were to surface water. Reporting from the new industries accounted for 91.7 % of the land releases on-site, 38.8% of the air releases, 21.2 % of the releases to underground injection wells, and 3.5% of the discharges to surface water. Off-site releases were 6.1% (444 million pounds) of the total releases in 1998. Off-site releases result when a facility sends quantities of a toxic chemical to another facility, where they are then released. Of these off-site releases, 65.6 % (292 million pounds) were to landfills/surface impoundments. Of the seven new sectors, two sectors (metal mining and electric utilities) accounted for 93.9% of the 4.9 billion pounds of total releases from these newly reporting industry sectors. The metal mining sector reported 3.5 billion pounds, or 71.2 %, of the 4.9 billion pounds. On-site releases were 99.97 % of the metal mining sector’s total releases and 98.9% of these on-site releases were to land.
• #31: Source: http://www.epa.gov/tri/tri98/data/datasum.htm The Toxics Release Inventory (TRI) is a publicly available database that contains information on specific toxic chemical releases and other waste management activities reported annually by certain covered industries as well as by federal facilities. This inventory was established under the Emergency Planning and Community Right-to-Know Act of 1986 (EPCRA), which requires facilities to use their best readily available data to calculate their releases and waste management estimates. If facilities do not have actual monitoring data, submitted values are derived from various estimation techniques. There are now nearly 650 toxic chemicals and chemical compounds on the list of chemicals that must be reported to EPA and the States under the EPCRA/TRI Program. A facility must report to TRI if it meets the following three criteria: • Conducts manufacturing operations within Standard Industry Classification (SIC) codes 20 through 39 and, beginning in the 1998 reporting year, if it is in one of the following industry categories: metal mining, coal mining, electrical utilities, RCRA Subtitle C hazardous waste treatment and disposal facilities, chemicals distributors, petroleum terminals, and solvent recovery services; (Also, federal facilities must report to TRI regardless of their SIC code classification.) • Employs 10 or more full-time equivalent employees; • Manufactures or processes more than 25,000 pounds or otherwise uses more than 10,000 pounds of any listed chemical during the reporting year.
• #32: About 7.6 billion tons of industrial solid waste are generated and managed on-site at industrial facilities each year. Almost 97 percent is wastewater managed in surface impoundments; the remainder is managed in landfills, waste piles, and land application units. Most of these wastewaters are treated and ultimately discharged into surface waters under Clean Water Act permits issued by EPA or state governments (National Pollutant Discharge Elimination System or NPDES permits). These wastes come from the broad spectrum of American industries. This guidance is not designed to address municipal wastes or wastes defined as hazardous under federal or state laws. Source: Guide for Industrial Waste Management EPA530-R-99-001
• #33: Source: Green Products by Design: Choices for a Cleaner Environment Much of the solid waste produced in the United States is not directly generated by consumers. Municipal solid waste, the focus of much public concern, represents less than 2 percent of all solid waste regulated under RCRA. in contrast, Industrial activities produce about 700 million tons of hazardous waste (a) and about 11 billion tons of non-hazardous wastes (b). NOTE: All numbers are estimates. The non-hazardous waste total has been rounded to reflect uncertainty. Much of the “solid” waste defined under RCRA, perhaps as much as 70 percent, consists of wastewater. The terms hazardous and non-hazardous refer to statutory definitions of Subtitles C and D of RCRA, respectively. The mining wastes shown in (b) exclude mineral processing wastes; the oil/gas wastes in (b) exclude produced waters used for enhanced oil recovery; the “other" category in (b) includes wastes from utility coal combustion. Figure: Adapted from U.S. Congress, office of Technology Assessment, Managing Industrial Solid Wastes From Manufacturing, Mining, Oil and Gas
• #34: MSW does not include wastes from other sources, such as construction and demolition debris, automobile bodies, municipal sludges, combustion ash, and industrial process wastes that might also be disposed in municipal waste landfills or incinerators. Source: CHARACTERIZATION OF MUNICIPAL SOLID WASTE IN THE UNITED STATES: 1997 UPDATE Prepared for U.S. Environmental Protection Agency, Municipal and Industrial Solid Waste Division, Office of Solid Wast, Report No. EPA530-R-98-007
• #35: Source: Municipal Solid Waste Generation, Recycling and Disposal in the United States: Facts and Figures for 1998 EPA530-F-00-024 In the United States, we generated approximately 220 million tons of municipal solid waste (MSW) in 1998--an increase of 4 million tons from 1997. The recovery rate for recycling (including composting) continued to grow but at a slower rate. In 1998, the nation’s overall recycling rate was 28.2 percent. This is up 0.8 percent from the previous year. MSW generation in 1998 remained relatively stable, at 4.46 pounds per person per day. Over the last few decades, the generation, recycling, and disposal of MSW have changed substantially. MSW generation has increased steadily from 1960, when it was 88 million tons per year. The generation rate per person, just 2.7 pounds per person per day in 1960, grew to 3.7 pounds per person per day in 1980; reached 4.5 pounds per person per day in 1990; and is now 4.46 pounds per person per day. Figure is from the Characterization of Municipal Solid Waste in the United States 1997 Edition