_GENERAL DOCUMENTS - C1981017 ‎(286)‎

• Permit No: C1981017
• IBM Index Class Name: GENERAL DOCUMENTS
• Doc Name: Bid Documents ‎(IMP)‎
• Media Type: D
• Archive: No

Instability of Fill Slopes Below Portal Benches
Although the fill slopes below the portal benches are eroding, surface runoff is
presently being controlled in accordance with the approved State program. As with
the road cuts, I share your concern about the long-term stability of these slopes. OSM
is working with the State to maximize reclamation of both the portal benches and the
fill slopes consistent with State and Federal requirements applicable to underground
mining features created prior to the enactment of SMCRA but used after that date.
Contamination of the Crystal River
You express concern that discharges from the mine portals have contaminated the
Crystal River. Specifically, you note that OSM has identified salinity in mine
drainage, and that an employee of the Colorado Division of Wildlife believes that the
Crystal River may have been degraded by toxins originating from the mine site.
I agree that the mine has a history of noncompliance with effluent limitations and
performance standards related to protection of the hydrologic balance. However,
these violations pertain primarily to inadequate sediment control and discharges of coal
finds before the mine ceased operation in 1991. In September, 1993, OSM sampled
discharges from various locations within the permit area, but found no violations of
effluent limitations. Drainage from the rock tunnel adit contained a higher level of
sulfates than background levels in Coal Creek and Dutch Creek, but the discharge was
not causing or contributing to a violation of State water quality standards for these
streams or the Crystal River.
The study referenced by the Colorado Division of Wildlife employee mentioned in
your letter consisted of a two-year macroinvertebrate analysis of the Crystal River
watershed. It was conducted under the auspices of the U.S. Forest Service in 1989-90
when active mining was still in progress. The study found that macroinvertebrate
biomass and diversity in the Crystal River decreased significantly below the river's
confluence with Coal Creek. In discussing this decrease, the report states that "fi]n
addition to sediment impacts at the lower two stations, it appeared that there may be a
non-selective toxicant, possibly from chemicals used in the coal mine operation,
affecting these ecosystems." However, the report contains no discussion of or basis
for this conclusion. There was no analysis of water chemistry, and no attempt was
made to identify or verify the existence of the alleged toxicant. Nor does the report
explain why sedimentation alone could not have caused the observed decrease.
Furthermore, the report does not examine the origins of the sediment found in the
lower Crystal River. Since Coal Creek is located in a geologically unstable area, the
mining operation is not the sole sediment source and the extent of its contributions
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