It seems there is reason to worry about water quality in these areas and with this type of mining:
Water emerges from the base of valley fills containing a variety of solutes toxic or damaging to biota (11). Declines in stream biodiversity have been linked to the level of mining disturbance in WV watersheds (12). Below valley fills in the central Appalachians, streams are characterized by increases in pH, electrical conductivity, and total dissolved solids due to elevated concentrations of sulfate (SO4), calcium, magnesium, and bicarbonate ions (13). The ions are released as coal-generated sulfuric acid weathers carbonate rocks. Stream water SO4 concentrations are closely linked to the extent of mining in these watersheds (11, 14). We found that significant linear increases in the concentrations of metals, as well as decreases in multiple measures of biological health, were associated with increases in stream water SO4 in streams below mined sites (see the chart on page 149). Recovery of biodiversity in mining waste-impacted streams has not been documented, and SO4 pollution is known to persist long after mining ceases (14).
Conductivity, and concentrations of SO4 and other pollutants associated with mine runoff, can directly cause environmental degradation, including disruption of water and ion balance in aquatic biota (12). Elevated SO4 can exacerbate nutrient pollution of downstream rivers and reservoirs by increasing nitrogen and phosphorus availability through internal eutrophication (15, 16). Elevated SO4 can also increase microbial production of hydrogen sulfide, a toxin for many aquatic plants and organisms (17). Mn, Fe, Al, and Se can become further concentrated in stream sediments, and Se bioaccumulates in organisms (11) (figs. S1 and S2).
A survey of 78 MTM/VF streams found that 73 had Se water concentrations greater than the 2.0 µg/liter threshold for toxic bioaccumulation (18). Se levels exceed this in many WV streams (see the chart on page 149). In some freshwater food webs, Se has bioaccumulated to four times the toxic level; this can cause teratogenic deformities in larval fish (fig. S2) (19), leave fish with Se concentrations above the threshold for reproductive failure (4 ppm), and expose birds to reproductive failure when they eat fish with Se >7 ppm (19, 20). Biota may be exposed to concentrations higher than in the water since many feed on streambed algae that can bioconcentrate Se as much as 800 to 2000 times that in water concentrations (21).
Potential for Human Health Impacts
Even after mine-site reclamation (attempts to return a site to premined conditions), groundwater samples from domestic supply wells have higher levels of mine-derived chemical constituents than well water from unmined areas (22). Human health impacts may come from contact with streams or exposure to airborne toxins and dust. State advisories are in effect for excessive human consumption of Se in fish from MTM/VF affected waters. Elevated levels of airborne, hazardous dust have been documented around surface mining operations (23). Adult hospitalizations for chronic pulmonary disorders and hypertension are elevated as a function of county-level coal production, as are rates of mortality; lung cancer; and chronic heart, lung, and kidney disease (24). Health problems are for women and men, so effects are not simply a result of direct occupational exposure of predominantly male coal miners (24).
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