Coal - Energy Policy Analysis: A Conceptual Framework - page 21

tions conducive to erosion. Soil removal from the area to be surface mined alters or destroys many
natural soil characteristics and may reduce its productivity for agriculture or biodiversity. Soil
structure may be disturbed by pulverization or aggregate breakdown. In arid areas like Montana,
it may take 150 to 200 years for biological productivity to recover (USGS 1979).
Air Quality
Removal of vegetative cover and activities associated with construction of haul roads, stockpiling
of topsoil, displacement of overburden, and hauling of spoil and coal increase the quantity of
dust around mining operations (Axtell 1978), especially in the western United States due to arid
climate and persistent winds. Dust degrades air quality in the immediate area, can have adverse
impacts on vegetative life, and may constitute a health and safety hazard for mine workers and
nearby residents (Murray 1978). Small dust particles less than ten microns, and especially those
less than two microns, are considered most dangerous to public health; they can be transported
up to twenty kilometers (about 12.4 miles) from mining operations (Dvorak 1977). The amount
of fugitive dust resulting from surface mining 100,000 tons of coal has been estimated at twenty-
two tons, 80 percent of which would settle within mine boundaries. Fifteen percent, or 3.3 tons,
would be dust of respirable size and might be carried further from the mine (Christman et al.
1980, 117).
Health effects on miners also include on-the-job accidents and exposure to high levels of noise
from use of some types of equipment (Christman et al. 1980, 117, 123). Noise from equipment and
vibration from blasting may also have detrimental effects on some nearby structures off the mine
site, thereby affecting the general public. Although these effects are regulated, noise, vibration,
and structural damage due to blasting continue to impose costs on some coal mining operations
in the United States today.
Water Quality
Surface mining can adversely impact the hydrology of any region. Deterioration of stream quality
can result from acid mine drainage; addition of heavy metals, toxic trace elements, and radioactivity;
high content of dissolved solids in mine drainage water; and increased sediment loads discharged
to streams. Waste piles and coal storage piles can yield sediment to streams, and leached water
from these piles can be acidic and contain toxic trace elements. Surface waters may be rendered
unfit for agriculture, human consumption, bathing, or other household uses. Controlling these
impacts requires careful management of surface water flows into and out of mining operations
(OSM 1979).
Flood events can cause severe damage to improperly constructed or located coal haul roads,
housing, coal crushing and washing plant facilities, waste and coal storage piles, settling basin
dams, surface water diversion structures, and the mine itself. Besides the danger to life and prop-
erty, large amounts of sediment and poor quality water may have detrimental effects many miles
downstream from a mine site after a flood.
Groundwater supplies may be adversely affected by surface mining (Dunrud 1976). These
impacts include drainage of usable water from shallow aquifers, causing loss of potable well-
water supplies; lowering of water levels in adjacent areas and changes in flow directions within
aquifers; contamination of usable aquifers below mining operations due to infiltration or per-
colation of poor-quality mine water; and increased infiltration of precipitation on spoil piles.
Where coal or carbonaceous shales are present, increased infiltration may result in increased