Final Report: Coal Combustion Wastes: New Concerns About an Old Problem

EPA Grant Number: R827581
Title: Coal Combustion Wastes: New Concerns About an Old Problem
Investigators: Congdon, Justin D. , Hopkins, William A. , Rowe, C. L.
Institution: Savannah River Ecology Laboratory
EPA Project Officer: Stelz, Bill
Project Period: August 15, 1999 through August 14, 2000
Project Amount: $67,698
RFA: Futures: Detecting the Early Signals (1999) RFA Text |  Recipients Lists
Research Category: Water , Sustainability , Land and Waste Management , Ecosystems , Ecological Indicators/Assessment/Restoration


Until recently, the effects of coal combustion residues on wildlife appear to have been underestimated. Recent studies indicate that disposal of coal combustion residues in aquatic systems may pose significant physiological and ecological problems that warrant attention from the scientific and regulatory communities. The objective of this project was to compile a comprehensive review and synthesis of the literature on coal combustion residue disposal in the aquatic environment. The synthesis will provide a statement of current views on the environmental effects of coal combustion residues, based on recent, peer-reviewed studies. The manuscript also will provide a guide for future environmental research needs associated with increased coal combustion in the future.

Summary/Accomplishments (Outputs/Outcomes):

The extensive literature review was completed to produce the synthesis of information on coal ash. More than 300 documents were received on a wide array of topics pertaining to chemical, biological, and ecological aspects of coal ash disposal practices. The final synthesis provides an overview of research related to environmental effects of disposal of coal combustion residues (CCR). The review and synthesis focused directly on aspects of CCR that have the potential to negatively influence aquatic organisms and the health of aquatic ecosystems. The synthesis identified major issues of concern, as well as areas that are in need of further investigation.

Intentional or accidental release of CCR into aquatic systems has generally been associated with deleterious environmental effects. A large number of metals and trace elements are present in CCR, some of which are rapidly accumulated to high concentrations by aquatic organisms. Moreover, a variety of biological responses have been observed in organisms following exposure to and accumulation of CCR-related contaminants. Fish kills and complete extirpation of some fish species have been associated with CCR release. In fish and other organisms, CCR exposure has led to numerous histopathological, behavioral, and physiological (reproductive, energetic, and endocrinological) effects. CCR also may have indirect effects on aquatic animals mediated by changes in resource abundance or quality. Recovery of CCR-impacted sites can be extremely slow due to continued cycling of contaminants within the system, even in sites that only received CCR effluents for short periods of time (~ 8 months in Martin Creek Lake, TX, for example).

The literature synthesis reveals important considerations for future investigations of CCR-impacted sites. Many studies have examined biological responses to CCR with respect to Se concentrations and accumulation, because of teratogenic and reproductively toxic effects known to be associated with this element. However, the complex mixture of metals and trace elements characteristic of CCR suggests that biological assessments of many CCR-contaminated habitats should examine a variety of inorganic compounds in sediments, water, and tissues before causation can be linked to individual CCR components. Most evaluations of effects of CCR in aquatic environments have focused on lentic systems and the populations of animals occupying them. Much less is known about CCR effects in lotic systems, in which the contaminants may be transported downstream, diluted or concentrated in downstream areas, and accumulated by more transient species. Although some research has examined accumulation and effects of contaminants on terrestrial and avian species that visit CCR-impacted aquatic sites, more extensive research is needed in this area. Effects in terrestrial or semiaquatic species range from accumulation and maternal transfer of elements to complete recruitment failure, suggesting that CCR effects need to be examined both within and outside of the aquatic habitats into which they are released. Requiring special attention are waterfowl and amphibians that use CCR-contaminated sites during specific seasons or life stages and are highly dependent on aquatic habitat quality during those periods.

Whether accidentally discharged into natural aquatic systems or present in impoundments that attract wildlife, CCR appears to present significant risks to aquatic organisms. Effects may be as subtle as changes in physiology or as drastic as extirpation of entire populations. When examined as a whole, research on responses of aquatic organisms to CCR suggests that decreasing the use of disposal methods that include an aquatic slurry phase may alleviate some environmental risks associated with the waste products.

Journal Articles on this Report : 1 Displayed | Download in RIS Format

Other project views: All 8 publications 1 publications in selected types All 1 journal articles
Type Citation Project Document Sources
Journal Article Rowe CL, Hopkins WA, Congdon JD. Ecotoxicological implications of aquatic disposal of coal combustion residues in the United States: a review. Environmental Monitoring and Assessment 2002;80(3):207-276. R827581 (Final)
  • Abstract from PubMed
  • Supplemental Keywords:

    fossil fuel, electricity, water pollution, heavy metals, arsenic, cadmium, selenium, ecotoxicology, sublethal effects., RFA, Scientific Discipline, Air, Waste, Ecosystem Protection/Environmental Exposure & Risk, Bioavailability, climate change, Fate & Transport, Ecological Risk Assessment, Atmospheric Sciences, Chemistry and Materials Science, Incineration/Combustion, Exp. Research/future, Futures, coal combustion wastes, emerging environmental problems, coal ash, fate and transport, environmental monitoring, trace elements, chemical composition, contaminant uptake, exploratory research, fossil fuel, water pollution, ecotoxicology, public policy, coal combustion, futures research, heavy metals

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    Progress and Final Reports:

    Original Abstract
    2000 Progress Report