Environmental Problems, Their Causes, and Sustainability 1

plant expansions, or sell them to other utilities, privatecitizens, or environmental groups.Proponents argue that this system allows the marketplaceto determine the cheapest, most efficient wayto get the job done instead of having the governmentdictate how to control air pollution. Some environmentalistssee this cap-and-trade market approach as animprovement over the regulatory command-and-controlapproach, as long as it achieves a net reduction in SO 2pollution. This would be accomplished by limiting thetotal number of credits and gradually lowering theemissions cap or annual number of credits, as has beendone since 2000.One of the neat things about the SO 2 emissionsmarket is that anyone can participate. Environmentalgroups can buy up such rights to pollute and not usethem. You could personally reduce air pollution bybuying a certificate allowing you to add 0.9 metric ton(1 ton) of SO 2 to the atmosphere and hanging it on thewall. You can purchase these certificates and give themaway as birthday or holiday gifts. See http://www.epa.gov/airmarkets/ for a list of brokers and other sellersof SO 2 permits.Some environmentalists criticize the cap-andtradeprogram. They contend that it allows utilitieswith older, dirtier power plants to buy their way outand keep on emitting unacceptable levels of SO 2 . Thiscould lead (as it has) to continuing high levels of airpollution in certain areas or “hot spots.”This approach also creates incentives to cheatbecause air quality regulation is based largely on selfreportingof emissions. To help keep the system honest,the environmentalists call for unannounced spot monitoringby the government and high fines for cheaters.In addition, the success of any emissions tradingapproach depends on how low the initial cap is set andthen on how much it is reduced annually to promotecontinuing innovation in air pollution prevention andcontrol. Without these elements, these critics say thatemissions trading programs mostly move air pollutantsfrom one area to another without achieving anoverall reduction in air quality.Good news. Between 1980 and 2002, the emissionstrading system helped reduce SO 2 emissions fromelectric power plants in the United States by 40%. Andthe cost of doing this was less than one-tenth the costprojected by industry because this market-based systemmotivated companies to reduce emissions in moreefficient ways.The EPA has also created an emissions tradingprogram for smog-forming nitrogen oxides (NO x ) in anumber of states in the East and Midwest. Emissionstrading may also be implemented for particulate emissionsand volatile organic compounds (VOCs) and forthe combined emissions of SO 2 , NO x , and mercuryfrom coal-burning power plants.This combined emissions trading scheme, proposedby the Bush administration in 2001 under itsClear Skies initiative, is strongly supported by the electricpower industry. The initiative aims for a 70% reductionin emissions of mercury, sulfur dioxide, andnitrogen oxides by 2018. But critics call this the DirtySkies plan, largely crafted by the country’s biggest airpolluters. According to Frank O’Donnell, executive directorof the Clean Air Trust, the Clear Skies plan was“drawn up by and for the big polluters.” Critics claimthat the plan will set caps too low, allow emissions oftoxic mercury to triple by 2013, cause a 50% increase inSO 2 emissions, and require no controls for reducingemissions of the greenhouse gas CO 2 .Environmentalists and health scientists are particularlyopposed to using a cap-and-trade program tocontrol emissions of mercury by coal-burning powerplants and industries because it is highly toxic, fallsout of the atmosphere fairly near such facilities, anddoes not breakdown in the environment. Coal-burningplants choosing to buy permits instead of sharply reducingtheir mercury emissions would create hot spotswith unacceptably high levels of mercury.Bad news. In 2002, the EPA reported results fromevaluation of the country’s oldest and largest emissionstrading program, in effect since 1993 in southernCalifornia. The EPA study found that this cap-andtrademodel “produced far less emissions reductionsthan were either projected for the program or couldhave been expected from” the command-and-controlsystem it replaced. The study also found accountingabuses, including emissions caps set 60% higher thancurrent emissions levels. Cap-and-trade programsneed to be carefully monitored.xHOW WOULD YOU VOTE? Should emissions trading beused to help control emissions of all major air pollutants? Castyour vote online at http://biology.brookscole.com/miller14.How Can We Reduce Outdoor Air Pollutionfrom Coal-Burning Facilities? PreventionIs BestThere are a number of ways to prevent and controlair pollution from coal-burning facilities.Figure 20-17 (p. 456) summarizes ways to reduce emissionsof sulfur oxides, nitrogen oxides, and particulatematter from stationary sources such as electric powerplants and industrial plants that burn coal.Good news. Between 1980 and 2002, emissions ofSO 2 from U.S. electric power plants decreased by 40%,emissions of NO x emissions by 30%, and soot emissionsby 75%. Emphasis has been on output approachesthat add equipment to remove some of the particulate,NO x , and SO 2 pollutants after they are produced (Figure20-18, p. 457). Pollution can also be reduced at thehttp://biology.brookscole.com/miller14455