The ash from municipal solid waste (MSW) incinerators contains very high levels of toxic metals, according to a study by the Environmental Defense Fund (EDF), a traditional environmental group based in New York City.
The study provides fuel for a heated debate occurring now in Washington, DC, where federal officials are trying to decide whether to define MSW incinerator ash as a "hazardous waste" or not. If MSW incinerator ash is defined as a hazardous waste, its disposal will be expensive; if it is not defined as a hazardous waste, its disposal will remain cheap. The financial feasibility of incinerating MSW will be heavily impacted by the decision.
Incinerating MSW looks like an extremely lucrative technology and large firms, such as Westinghouse, and pushing their way into the business in hopes of making a killing.
The EDF study shows that MSW incinerator ash contains "very high levels" of lead, arsenic, cadmium and mercury, all of which are toxic metals. EDF gathered data from the federal Environmental Protection Agency (EPA), from five state governments, and from two private firms. The data represented Extraction Procedure (EP) tests conducted on ash resulting from the incineration of municipal solid waste. The EP toxicity test is an official EPA test used to determine whether a substance is legally definable as a "hazardous waste" or not under the Resource Conservation and Recovery Act (RCRA).
MSW ash has two components: it is 10% fly ash and 90% bottom ash. EDF found that "all available results from the testing of MSW incinerator ash indicate the routine presence of very high levels of several toxic metals." Specifically, EDF found that lead and cadmium levels in the fly ash portion of MSW often exceed the limits required for classification of the waste as "hazardous" under Subtitle C of RCRA.
EDF has sent its results with a letter to over 100 MSW incinerator owners/operators, urging them to have EP toxicity tests conducted on their ash residues. EDF will gather the results from these tests, if results are released by the owners/operators, and will issue another report.
For further information, contact Michael Herz, Environmental Defense Fund, 257 Park Avenue South, NY,
NY 10010; phone: (212) 686-4191.
--Peter Montague, Ph.D.
Descriptor terms: ash; msw; incineration; studies; edf; federal; hazardous waste; toxic waste; epa; toxicity; resource conservation and recovery act; rcra; cadmium; lead; ep toxicity test;