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Mr. J. David Holm Water Quality Control Division Page 6 CMLRB, all of the correspondence and submittals pertinent to TR-26 have been specifically sent to the CCCD, PAES and other project opponents. Discharge Point 002 Given the fact that the TR-26 response activities comprehensively addressed both the groundwater issues and the surface water implications of the conditions in the alluvial aquifer, BMG concurred with the terms of the draft permit which contemplated the incorporation of the TR-26 response activities into the CDPS permit as a BMP for the purposes of addressing the surface water issues. Many of the comments were based upon a misunderstanding or mischazacterization of TR-26 and the complex geohydrology surrounding the West Pit, and proposed solutions involving either the identifcatioa and monitoring of surface seeps and/or the identification of certain groundwater monitoring wells surrounding the West Pit as "outfalls". As described in more detail in the attached memorandum, both of these approaches would be entirely inappropriate and ineffective given the progress of implementing West Pit response actions at the site. [See response to RMC General Comment 1, Attachment A, pp. 8 through 9] We would suggest that a much more effective approach to address DP-002 would involve a more definitive delineation of the obligations of the permittee with respect to the control and monitoring of DP-002. Specifically, we would propose that DP-002 remain as an outfall which is controlled by a BMP-oriented approach which specifies that the water level in the West Pit must be maintained at an elevation of 8583 feet above mean sea level (amsl) as a thirty (30) day average measured at the backfill groundwater monitoring well BF-4. This water level will maintain the hydraulic gradient in a direction from the Rito Seco to the pit thereby assuring that the potential for the West Pit to function as a source for future potential contamination of the surface water is eliminated. The hydrologic basis for this conclusion is set forth in Section 3.0 of TR-26. The monitoring plan approved for TR-26 is designed to monitor the effectiveness of this response activity with respect to the protection of both surface water and groundwater