FAQs
Q. What is coal ash?
A. Coal ash, which includes fly ash, is the residue of minerals and unburned carbon that remain following the combustion of coal in power plants to generate electricity. Coal ash is similar in consistency to talcum powder. With the installation of pollution control devices on power plants in recent decades, the residue collected by that equipment requires further management.
Q. Why can't Constellation Energy simply eliminate the production of coal ash?
A. Demand for electricity in Maryland and the nation continues to rise and the capacity to generate enough electricity is increasingly strained. Maryland's Public Service Commission has warned of potential brownouts in the near future because of insufficient electricity-generating capacity. While Constellation Energy is pursuing opportunities to create new generation capacity through means other than coal, such as nuclear and natural gas, the reality is that coal-fired generating plants remain essential to meeting Maryland's growing electricity demand. Coal ash is an inescapable result of coal combustion, so finding ways to manage and re-use coal ash are essential.
Q. What are the uses of coal ash?
A. Coal ash has a number of useful, eco-friendly applications. It is used to manufacture cement, concrete, asphalt and other building materials, to refill surface mines, and to create stable foundations for roads, embankments and pavements. The U.S. Environmental Protection Agency notes on its Web site that the use of coal ash and other coal combustion products "yields environmental, economic, and product-performance benefits." The reuse of coal ash saves "virgin resources, and reduces energy consumption and greenhouse gas emissions," says the EPA. Coal ash can be substituted for cement in making concrete, natural gypsum in making wallboard, and gravel in making roofing granules, reducing the need to mine these products and lessening the demand to open new mines that disturb the land and destroy wildlife habitats. Coal ash possesses cementing properties in the presence of lime, so adding it to cement yields concrete that is stronger and more durable.
Q. What happens to the coal ash Constellation Energy produces in its Maryland power plants?
Constellation Energy's coal-burning power plants in Maryland produce nearly 800,000 tons of coal ash and byproducts annually. Approximately 60 percent of that ash is used beneficially to produce such products as blasting grit, flowable fill, cement and concrete. Other ash is used as structural fill to reclaim surface mines or to provide backfill for road construction. Constellation Energy's beneficial use rate is well above the industry average of 43 percent. The remaining ash is properly disposed of in a permitted landfill.
Q. Who regulates coal ash disposal?
A. In Maryland, the Department of the Environment (MDE) regulates coal ash use in reclamation, and also regulates disposal. MDE requires pollution prevention measures, groundwater monitoring and dust control. Maryland state law specifies that coal ash is not a hazardous waste.
Q. What does the U.S. Environmental Protection Agency say about coal ash?
A. The EPA has conducted two regulatory determinations on the management and use of coal combustion products, and has determined that "these materials did not warrant regulation as a hazardous waste."
Q. Is coal ash toxic?
A. According to the U.S. Environmental Protection Agency, "studies and research conducted or supported by EPA, Electric Power and Research Institute (EPRI), government agencies, and universities indicate that the beneficial uses of coal combustion products have not been shown to present significant risks to human health or the environment. As with many other common substances, precautions and sound management practices should be applied when using coal combustion products."
Q. Should I be concerned about coal ash?
A. With proper handling and disposal, coal ash poses no danger to humans or the environment.
Q. Does coal ash contain mercury?
The coal from which coal ash results contains trace amounts of mercury. The EPA Web site cites studies demonstrating that the release of mercury into the environment from coal combustion products (CCPs) is "negligible."
Q. Does coal ash emit radiation?
A. Coal contains naturally occurring radioactive elements. The EPA has classified coal ash as “diffuse, naturally occurring radioactive materials,” which is the agency's most benign radioactive classification. The EPA notes that “the level of radioactivity in combustion products (such as coal ash) is about the same as the level found in surface rocks and soil. A long-term Tennessee Valley Authority study of a 42-acre site that used more than 1 million cubic yards of coal ash in structural fill indicated that ambient radon levels measured directly over the fly (coal) ash fill were comparable to the levels measured in control areas without fly (coal) ash.”
Q. Does coal ash pose an air-borne health hazard?
A. The EPA recommends that routine precautions be taken during transportation and delivery of dust-containing products such as coal ash. Risk assessments performed by EPA indicate that the placement of coal ash in surface mines or landfills does not present a significant airborne risk. MDE's chief public health officer does not consider dust levels at or near the BBSS site to be dangerous to public health.