GENERAL42100

• Permit No: M1988112
• IBM Index Class Name: General Documents
• Doc Date: 8/9/2000
• Doc Name: FAX
• From: STATE OF COLO NATURAL RESOURCES SECTION
• To: JIM DILLIE
• Media Type: D
• Archive: No

The Division did not include in the Order all the data upon which it relied in
malting its w ester quality impact and penalty determinations. Since the Order was signed.
much of this information has been provided to individuals representing CCCD and PASS
upon their request. It is available for any member of the public to inspect. Any
interested person should call Carla Lenkey, Enforcement and Compliance Specialist at
[phone], or write to her at: Water Quality Control Division, 4300 Cherry Creek
Drive South, Denver, Colorado 80246-1530.
As detailed above in Response #3, the Division believes that sufficien:
information exists to conclude that surface seeps from the West Pit have ceased. There is
also sufficient evidence to document that dischazges entering the Rito Seco fr~>m the
alluvium have ceased. The Division relies on documentation from Battle Mo~mtain's
hydrology consultant (Januazy 25, 2000 memorandum and supporting documentation
from Jim Finley, Shepherd Miller, Inc., to Bill Lyle of Battle Mountain) chat the
hydraulic gradient has been reversed as anticipated in TR-26, thereby eliminating the
flow of groundwater through the "window" from the Pit. As for the contaminated
groundwater plume in the alluvial aquifer, the Division relies on results from the TR-26
geohydrologic characterization, monitoring, and containment program to support its
finding that the plume remaining afrer hydraulic gradient reversal has not adversely
affected surface waters.
7. CCCD and PASS asserted that the settlement fails to consider relevant
information provided in the MLRB record for the San Luis Facility, for example, a
specification in the MLRB Permit that the mine would be a "zero dischazge facility."
The Groups also claimed that concerns regarding interaction between the West Pit and
the alluvial aquifer were so substantial during MLRB proceedings that the slurry wall
was included as part of the MLRB application and permit as a preventative measure.
The Division conducted an extensive review of all the relevant parts of the MLRB
record in making its penalty determination under the Order. It is the Division's
understanding that the "zero dischazge facility" reference in the MLRB Permit deals with
the "closed loop" cyanide benefaction process which vas conducted within contained
systems, and disposal of the associated tailings in a lined facility, neither of which is
associated with discharges from the West Pit.
The Division's reading of the MLRB record on the slurry wall issue indicates that
the wall was a contingency considered for controlling inflow and stabilizing'he south
wall of the West Pit, anticipating that the Pit was to be left unfilled. The concern was that
without a slurry wall under those circumstances, water from the Rito Seco w~~uld actually
flow into the pit. At the time Battle Mountain made the proposal to backfill rite West Pit
under TR-18 to its MLRB Permit, it withdrew the slttrry wall concept as no 1 anger
necessary. It is the Division's understanding that the slurry wall was not considered as a
water quality control measure in either the original MLRB permit or TR-18 to that
permit. The Division has confirmed its understanding with DMG. The Divi>ion,
therefore, believes that references in MLRB's record with respect to construe:tion of a
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