U.S. Water News Online
RESTON, Va. -- Cleanup standards for more than half a
million abandoned mines
scattered throughout the nation need to take into account local
geology as
well as results of human activities, according to a new report by the
U.S.
Geological Survey (USGS). As a case in point, the study cites
toxic
contamination from an open-pit gold mine at Summitville, Colo.
"The very names of creeks in the Summitville area -- Bitter Creek,
Iron
Creek, and Alum Creek -- suggest that the waters were naturally
contaminated
by metals that raised the acidity long before the recent Summitville
mine
opened," said Trude King, editor of the 38-page USGS report. "An
important
part of the remediation efforts at the mine has been determining the
natural
condition of the area," noted King. "Knowing the background levels of
metals
gives us an appropriate goal for remediation that is cost-effective
and
technologically feasible."
The USGS report "Environmental Considerations of Active and
Abandoned Mine
Lands: Lessons from Summitville, Colorado" notes that scientists
determined
that acidic contamination of water around the abandoned mine is the
result of
both the area's geology and of human action. When the mine closed in
1992,
the state of Colorado asked the U.S. Environmental Protection Agency
to take
over the site and stop the leakage of water contaminated with heavy
metals
and cyanide from reaching the Wightman Fork of the Alamosa River. The
total
cost of remediating the site has been estimated at $120 million.
Return to the U.S. Water News' Archives page
Or
Return to the U.S. Water News Homepage
uswatrnews@aol.com