Chapter 5 Threats
Fish and wildlife damage from exposure to coal ash slurry ranges from physiological, developmental, and behavioral toxicity to major population and community-level changes (Lemly and Skorupa 2012) . The earliest reported coal ash pond failure in North Carolina occurred in 1976 and resulted in selenium poisoning that extirpated 19 species of fish in Belews Lake (Lemly and Skorupa 2012) . Following a 2008 release of coal ash in Tennessee, an assessment of effects on aquatic species found low potential exposure risk to selenium in Tree Swallows and bats; to aluminum in Mink, Killdeer, Mallard, and Raccoon; and to arsenic in Killdeer (Meyer et al. 2014) . Other studies conducted by Bryan et al. (2003, 2012) evaluated the risk to birds attracted to coal ash settling basins for nesting and the exposure of nestlings to contaminated food. Results indicate arsenic, cadmium, and selenium concentrations were elevated in feather, liver, and carcass, but only liver selenium concentrations approached levels of concern (Bryan et al. 2003, 2012) . Exposure is suspected to occur from bioaccumulation concentrations in the food chain, primarily through insects consumed by insectivores and omnivores. Because selenium builds up through the food chain rather than through aqueous exposure, tissue selenium concentrations may increase gradually over a period of several years (Mathews et al. 2014) . Tissues from Raccoons exposed to coal ash showed higher levels of arsenic in hair, iron in muscle, nickel in hair, selenium in hair and muscle, strontium in hair, and vanadium in hair and liver when compared to unexposed animals (Souza et al. 2013) . However, long-term monitoring is needed to understand the factors that control when coal fly ash contaminants are more likely to biomagnify (Mathews et al. 2014) . Coal-fired power plants pump large volumes of water to produce electricity. Aquatic organisms can be entrained or impinged unless measures are sufficient to keep organisms from being impacted. After water is used for electricity production, it is returned to surface waters, but the temperature can be considerably higher than the temperature of the receiving waterbody. Heated discharge can create refugia for nonnative species and alter aquatic community composition. 5.5.3 Oil and Gas Extraction – Anticipated Impacts North Carolina has limited oil and gas reserves within shale deposits in the Triassic Basin of the Piedmont ecoregion, primarily in the Durham, Sanford, and Wadesboro subbasins of the Deep River Basin and in the Dan River Basin within portions of Stokes and Rockingham counties. Offshore oil and gas exploration continues to be debated, but no offshore extraction is currently allowed because it is generally controlled by federal regulations and processes. Two technological advances now make these oil and gas resources more accessible: horizontal drilling and hydraulic fracturing. Horizontal drilling allows access to a larger subterranean area with a single surface drilling location. This technique provides access to large subterranean areas that may be inaccessible otherwise, thereby increasing potential profits. Hydraulic fracturing, also known as fracking, is a well-stimulation technique in which pressurized water,
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2025 NC Wildlife Action Plan
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