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IV. Hydrologic Balance The Division is in possession of considerable water quality and water quantity data from the monitoring program approved in TR-14 to the SGC permit, but currently has no concise assessment from SGC of the impact of plugging on flow and water quality from other areas. If GKMC fails to adequately operate the American Tunnel water treatment facility, what are SGC's plans to address groundwater quality at the Gold King mine? SGC's placement of bulkheads in the Sunnyside Mine was approved in TR-14. TR-14, unlike most Permit Technical Revisions, was treated as an Amendment and required full Public participation and Board approval. Commitment #1 in the approval of TR-14 addresses how any surface expression of flows would be handled by the DMG. The voiuntary Consent Decree Agreement between SGC and CDPHE-WQCD resulted from the determination recited in Commitment #1 and SGC's efforts to satisfy the DMG and the CDPHE-WQCD on this issue. SGC and all regulatory agencies participated in this process. It is SGC's position that CDPI-IE-WQCD requirements have been fully satisfied by SGC's mitigation efforts and results with respect to any surface expression of groundwater flows, as evidenced by CDPHE's termination of the Consent Decree, also approved by the Court. Attached is the A-72 assessment graph used by CDPHE-WQCD to assess the final overall impact of plugging on flow and water quality. This assessment graph includes data for two yeazs after termination of the Consent Decree. The base line or predicted quality is as if all discharges from the Sunnyside Mine were receiving full treatment. SGC believes the current results indicate that SGC has minimized impact to the hydrologic balance. Additionally, the historic flow originating in the first 8000' ofthe American Tunnel could not have been affected by SGC's mining activities. This portion of the tunnel has always belonged to GKMC and has only been used by SGC for access to the Sunnyside Mine. This was originally recognized by WQCD- CDPHE in the form of a loading credit to the CDPS dischazge permit which is an attachment to the M- 1977-378 consolidated permit application (1987). TR-14 was a modification to the conceptual reclamation plan that supplied design details and moved the bulkhead location from neaz surface to 8000' in-bye. The monitoring period required by TR-14 lasted from 1996-2001. During this period, no drainage originated from the bulkhead (8000' in-bye) to the fault zones (3000' in-bye). Placement of bulkheads No.2 and No.3 were approved in TR-25 to further isolate the fault zone flow and near surface flows which existed historically from property not owned or disturbed by SGC. This approach also indicates that SGC has been sensitive to and successful in minimizing disturbance to the hydrologic balance. In regazds to the question concerning SGC's plans to address groundwater quality at the Gold King Mine in the event GKMC fails to adequately operate the American Tunnel water treatment facility, SGC does not have any plans nor does SGC's submitted data reflect a deterioration in water quality at the Gold King. SGC's monitoring data and analysis previously submitted to the Division in the 2001 Annual Report for TR-14 addressed this issue and contained the following analysis for Gold King water quality.