Response to comments by Dunford and DeForest et al.
ABSTRACT The comments by Dunford and DeForest et al., while projecting an illusion of science-based critique, are really about protecting a corporate agenda to maintain the status-quo of minimal regulations governing coal ash disposal in the United States. In our reply, we expose this agenda through factual information that counters every allegation and assertion, which were clearly intended to minimize and downplay historical and current impacts of coal ash toxicity to fish and wildlife. We issue a challenge to the Utilities Solid Waste Activities Group, who paid for the comments opposing our paper. Rather than using your energy and funds on attempts to discredit our report, please take the high road in representing your membership by vocally supporting operational changes and regulatory steps that will expedite the end of surface impounded coal ash.
- Environmental Science & Technology 05/2013; 47(19):11363-11364. DOI:10.1021/es3053575 · 5.48 Impact Factor
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ABSTRACT: The combustion of coal to generate electricity produces about 130 million tons of coal combustion residues (CCRs) each year in the United States; yet their environmental implications are not well constrained. This study systematically documents the quality of effluents discharged from CCR settling ponds or cooling water at ten sites and the impact on associated waterways in North Carolina, compared to a reference lake. We measured the concentrations of major and trace elements in over 300 samples from CCR effluents, surface water from lakes and rivers at different downstream and upstream points, and pore water extracted from lake sediments. The data show that CCR effluents contain high levels of contaminants that in several cases exceed the U.S. EPA guidelines for drinking water and ecological effects. This investigation demonstrates the quality of receiving waters in North Carolina depends on (1) the ratio between effluent flux and freshwater resource volumes and (2) recycling of trace elements through adsorption on suspended particles and release to deep surface water or pore water in bottom sediments during periods of thermal water stratification and anoxic conditions. The impact of CCRs is long-term, which influences contaminant accumulation and the health of aquatic life in water associated with coal-fired power plants.Environmental Science & Technology 09/2012; 46(21). DOI:10.1021/es303263x · 5.48 Impact Factor
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ABSTRACT: An 18 month investigation of the environmental impacts of the Tennessee Valley Authority (TVA) coal ash spill in Kingston, Tennessee combined with leaching experiments on the spilled TVA coal ash have revealed that leachable coal ash contaminants (LCACs), particularly arsenic, selenium, boron, strontium, and barium, have different effects on the quality of impacted environments. While LCACs levels in the downstream river water are relatively low and below the EPA drinking water and ecological thresholds, elevated levels were found in surface water with restricted water exchange and in pore water extracted from the river sediments downstream from the spill. The high concentration of arsenic (up to 2000 μg/L) is associated with some degree of anoxic conditions and predominance of the reduced arsenic species (arsenite) in the pore waters. Laboratory leaching simulations show that the pH and ash/water ratio control the LCACs' abundance and geochemical composition of the impacted water. These results have important implications for the prediction of the fate and migration of LCACs in the environment, particularly for the storage of coal combustion residues (CCRs) in holding ponds and landfills, and any potential CCRs effluents leakage into lakes, rivers, and other aquatic systems.Environmental Science & Technology 12/2010; 44(24):9272-8. DOI:10.1021/es1026739 · 5.48 Impact Factor