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MERCURY

Mercury (Hg) is a toxic metal that causes severe neurological damage in humans, particularly in fetuses and young children. Regulators want to control emissions from utility powerplants, which emit 48 tons of mercury annually, the country's single largest source of mercury pollution. The United States has about 1,200 coal-fired power plants, many built in the 1960s.

One promising technology for eliminating mercury from utility smokestacks is Activated Carbon Injection (ACI), a state-of-the-art technology that removes 80 percent of the mercury from stacks.  It is being tested at Gaston 3, a coal-burning power plant located in Alabama owned by Southern Company.  The process:

Stack flue gas passes through an electrostatic precipitator, then activated carbon dust is injected into the flue gas and particles of mercury cling to the carbon, which is then trapped by a second filter (baghouse) that collects it and is then discarded as toxic waste. This combination, which exists at only two plants nationwide, performs better than other configurations. Gaston 3 is a small plant at 270 megawatts. The combination mercury elimination unit cost $500,000, has a 40-foot carbon silo and a rubber hose to carry the carbon to the injector nozzles.

Unfortunately, neither ACI nor any other current technology can achieve the targets mandated by the Clean Air Act -- a 90 percent reduction in mercury emissions by 2007. Instead, the Bush administration wants to use a "cap-and-trade" program whereby companies either control their own mercury emissions or buy "allowances" from other companies that have already controlled their emissions.  The new EPA regulation proposes a new target, a 29 percent reduction by 2007 and an industry-wide reduction of 70 percent by 2018.

 Picture of Mercury

Carbon injection has its disadvantages. Baghouses are expensive and carbon for the system costs approximately $600,000 per year. There are currently a limited number of carbon suppliers and the quantities needed to supply more than 1,000 plants are not available. Plants without baghouses also cannot resell fly ash from their precipitators as a concrete additive because tests have shown that the activated carbon interferes with chemicals used in making concrete.

Innovative pollution control equipment will not be ready to approach 90 percent removal for years.  One-size-fits-all approach does not work. Technology to remove SOx and NOx extracted one type of ionized mercury compounds such as mercury chloride or mercury oxide, but does not work in removing elemental mercury -- the vaporized metal. Power plants emit both pollutants in varying proportions depending on coal type, flue-gas temperature and plant configuration.

Coal switching is complicated by different types of mercury and amounts of sulfur in coal from different regions.  Western coal emits high levels of elemental mercury.  Appalachian bituminous coal emits high levels of ionized mercury.  Appalachian coal has more sulfur, which would require plants burning it to install expensive "scrubbers" to avoid emissions that cause acid rain worse.

Environmental controls account for one fourth to one third a power plant's cost. A full suite of controls, including precipitator, baghouse and SOx and NOx equipment, could cost more than $80 million at Gaston 3.  Large 1,000 megawatt power plant controls can run as high at $300 - $500 million.

New Information on Mercury Pollution from Vehicles

According to a new analysis by the Clean Car Campaign, a record 18,000 pounds of mercury pollution was released into the environment last year in the U.S. when scrap vehicles were recycled.  An estimated 259,000 pounds of mercury have been released into the environment over the past 30 years.  Most troubling, according to the analysis, is that an equal amount could be released over the next two decades if programs are not put in place to recover the mercury in vehicles before they are scrapped. View the report.

EPA Issues Report on Mercury In Lakes

The Environmental Protection Agency has determined that more than half of all freshwater fish it sampled from America's lakes could be unsafe for women of childbearing age to eat twice a week. EPA has not established a safe limit for freshwater fish and mercury levels outlined in the report will not necessarily make consumers sick. The EPA has determined there is no health risk for women and children eating less than 0.1 micrograms of mercury per kilogram of body weight per day, but less than half the fish in the new survey met that standard, assuming two fish meals a week. 

More than three-quarters of the fish sampled had mercury levels that may be unhealthy for children younger than 3. The data, collected between 1999 and 2001 on 2,547 fish from 260 lakes, are part of the first-ever nationwide study the EPA has conducted on freshwater fish in an ongoing four-year project.

EPA and the Food and Drug Administration have warned pregnant and nursing women and young children against eating more than a small amount of canned albacore white tuna once a week because of mercury contamination, based on analyses of commercial saltwater fish sampled from the marketplace.

As of 2002, 43 states had warned residents to limit how much freshwater fish they consume, restrictions that encompass 30 percent of the nation's lakes and 13 percent of its rivers.

According to the EPA, some mercury exposure comes from industrial air pollution that mixes into water and gets into the food supply when it builds up in fish. Coal-fired power plants are the greatest U.S. source of mercury pollution. <NITF>President Bush has proposed regulations that would reduce pollution from mercury plants by 70 percent by 2018.

Mercury, a metal, is toxic and can cause neurological and developmental problems in children.

AAEA Organization Goals:

1. Protect the environment.
2. Promote the efficient use of natural resources.
3. Enhance human, animal and plant ecologies.
4. Increase African American participation in the environmental movement.
5. Deliver information and services directly into the black community.
6. Clean up neighborhoods by implementing toxics education, energy, water and clean air programs.
7. Include an African American point of view in environmental policy decision-making.
8. Resolve environmental racism and injustice issues through the application of practical environmental solutions.