LITHOGENIC ATMOSPHERIC PARTICULATES IN THE VICINITY OF MOUNTAINTOP COAL MINES, WEST VIRGINIA, USA

Mountaintop removal mining (MTM) is a widely used method of coal extraction in the U.S. Appalachian region, exposing coal for production by excavation of coal overburden using explosives. Residents living near MTM operations are potentially at risk because many of these communities are located in narrow hollows immediately below mountaintops being worked for coal. Epidemiologic studies show disparities in certain cancer rates and mortality, and the rates of birth defects, respiratory disease, cardiovascular disease, and kidney disease, in areas with ongoing MTM compared to non-MTM areas [1].

In the present study, we investigate the air quality impact of MTM by comparing the amount and geochemical characteristics of atmospheric particulate matter (PM) collected in active MTM areas in south central West Virginia with in-state controls having underground coal mining or no mining whatsoever. The study is part of a collaborative investigation of environmental factors that may contribute to health disparities associated with MTM. Air quality sampling consisted of coarse (> 2.5 µm) and fine (≤ 2.5 µm) PM samples collected in 24-hour increments over five separate one-week periods between June, 2011 and May, 2012. We did not attempt to synchronize PM sampling with MTM blasting events.

PM results are consistent with episodic input of lithogenic (rock-derived) material from local sources. Relative to a non-mining control, PM samples from two MTM sites, collected in June, 2011, show pronounced enrichment in elements associated with crustal sources (Ga, Al, Ge, Rb, La, Ce), without enrichment in anthropogenic elements (V, As, Cd). In August, 2011, PM samples collected at the same two MTM sites do not show enrichment in crustal elements, suggesting that local PM contribution is intermittent. Passive samplers were deployed at three MTM sites and controls from May to August, 2012, to obtain PM samples integrated over longer periods. Preliminary results show higher dry deposition fluxes at the MTM sites, for both crustal and anthropogenic elements. Elevated ambient PM is associated with adverse health outcomes, including higher rates of respiratory and cardiovascular diseases [2].

[1] Hendryx, M., in press, J. of Rural Healthdoi:10.1111/jrh.12016.

[2] U.S. EPA, http://www.epa.gov/air/particlepollution/health.html