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APPENDIX C
VALLEY FILL LEACH AREA No. 2
CLOSURE PLAN
July 1995
APPENDIX C
VALLEY FILL LEACH AREA No. 2
CLOSURE PLAN
July 1995
Valley Fill Leach Area 2 Plan and Compliance Schedule for Post-Closure Monitoring
1.0 General
This plan and compliance schedule for Valley Fill Leach Area 2 (VF2) has been prepared to comply with the requirements of Section 5.0 of the March 12,1992 Stipulation and Consent Order,
Docket No. GW-90-03-A. This plan also supercedes all other similar descriptions and details that may have been submitted and/or discussed concerning the post-closure monitoring of VF2.
The requirements for ground water quality monitoring are applicable only to monitoring well MW-9.
2.0 Closure Approval
The closure of VF2 was conditionally approved by the Utah Department of Environmental Quality - Division of Water Quality in correspondence dated May 30, 1995. Item 8 of that correspondence
required the preparation and submittal for approval of a post-closure monitoring plan. This fulfills that requirement. Final closure approval was given for VF2 by UDWQ in March 2001.
3.0 Facility Post-Closure Monitoring Plan and Schedule
3.1 Closure and Monitoring Schedule
Physical closure of VF2 commenced in June 1995 with the conditional approval from the UDWQ dated May 30, 1995. The schedule called for the completion of all VF2 shaping, contouring,
cover placement and seeding by October 1995. Barrick completed the required 5-year post-closure monitoring of the leakage collection system in April 2001 and installed drillouts through
the liner to provide free draining of infiltrated meteoric water. Barrick demonstrated that post-closure monitoring results met previous modeled predictions for the system. Long term
physical, facility water, and ground water quality monitoring will continue, as described in Section 3.2, through the term of the permit.
3.2 Water Quality Monitoring
Appendix A to Permit UGW450002 is the Water Quality Assurance - Quality Assurance/Quality Control Plan (QA/QC Plan) developed for the Barrick Mercur Mine. All specific components related
to the monitoring of water quality from the ground water quality monitoring of well MW-9 can be found in Appendix A to the permit. Please note that the reporting of data to the UDWQ
will be consolidated whenever possible.
3.2.1 Ground water
The ground water quality monitoring program involves only monitoring well MW-9 pursuant to the Stipulation and Consent Order. Details of this program can be found in Appendix A. A summary
is as follows:
( Semi annual sampling & water elevation readings will be obtained through the life of the permit.
( Water quality analysis will be for water chemistry specified in Appendix A.
( Reports to UDWQ will be on a semiannual basis as required by the permit Part I.I.1.
3.2.2 Facility
Facility monitoring involves cover monitoring and collection of water levels
from the cistern drillouts. A summary is as follows:
3.2.2.1 Former Production Cistern
( The former production cistern was abandoned with the approval of the Executive Secretary following the 5-year post-closure monitoring that was completed in April 2001. Two drillouts
were installed in 2001 to allow for free draining of the former cistern. Water levels will be measured on a quarterly basis.
3.2.2.2 Leakage Collection System
( The leakage collection system pumps and electric paneling were removed following the completion of the 5-year post-closure monitoring period. The leakage collection system is in-place.
UDWQ approval will be necessary prior to any sampling, monitoring, or reporting modifications or abandonment of the system.
3.3 Facility Physical Monitoring
Post-closure physical monitoring will be principally designed to satisfy the requirements of the Utah Department of Natural Resources - Division of Oil, Gas & Mining (UDOGM) and the
Utah Department of Environmental Quality - Division of Water Quality (UDWQ).
Monitoring of the revegetative effort is required by UDOGM for a minimum of three years or until adequate plant growth has been attained, is self-propagating, and is in accordance with
the surety bond release provisions. Monitoring of facility stability, erosional impacts, and general security matters will be maintained until all Mercur site responsibilities have been
accomplished by Barrick. Long term physical monitoring of VF2 will generally consist of inspections for cap erosion, quarterly water level measurements in cistern drillouts, settlement,
animal burrows, drainage ditch integrity, and plant growth. Immediate repairs will be undertaken as necessary to return the spent ore cover to the original post-closure conditions.
Access to the closed and reclaimed VF2 will be limited under the current conceptual post-closure public access corridor plan. Barrick’s conditional use permit with Tooele County and
agreements with adjacent landowners will be refined prior to December 1997.