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~' ~= M M they were collected, and provide any other pertinent information that would indicate that these samples are representative of the heap leach mass as a whole, if in fact they are to be used for permit-specific uses that will require representative sampling. Aor 13 Letter. Use of Pad #1 Material for Proposed Applications. It is proposed that material from Pad 2 "will be used to construct the Phase II toe berm, the Highway 67 realignment embankment, and will be used as a source of Select Structural Fill for the downstream face of Phase I Toe Berm." Notwithstanding that the geochemical assessment reported in Attachment #1 may be non- representative or inappropriate, and proceeding on the assumption that all units are in "ue/L," the results indicate that the Pad #1 material has the capacity to produce toxic drainage. [Toxic drainage in this context is taken to be that having water quality parameters which exceed the proposed "numeric standards" shown in the Stream Classifications and Water Quality Standards of the WQCC Proposal. The "Temporary Modifications and Qualifiers" were not applied for this assessment. (See later discussion for explanation.)] A comparison of data in Attachment 1 and the proposed "numeric standards" indicates there are water quality exceedances for pH, CN, NH„ NOz, CI. Based on the available geochemical data and knowledge that Pad #2 has not been completely rinsed, I must conclude that the Pad #2 material is geochemically unsuitable for any of the proposed uses identified in the May 2 Letter. Use of the Pad #2 materials in those locations apparently would cause discharges to Arequa Gulch to exceed the proposed "numeric standards" identified in the WQCC Proposal. Responses to DMG's letter of April 2, 1995. 1. All of the materials identified on page 4 of the May 2 letter, have been reviewed, and assessments were made on the basis of study and consideration of all of those. The remaining arguments and refutations expressed in this section do not compel me to revise previous interpretations about either the general state of the Cripple Creek ore and waste, the standards by which DMG must assess leaching tests, the results of the tests themselves, or the manner by which the leaching tests were used to determine whether the Cripple Creek ores and waste have or will develop the potential to generate acid and toxic materials. The argument, "ambient" water quality in Arequa Gulch should become the applicable water quality standard, would be compelling if it could be shown that the long-term standards which will be applicable to discharges to Arequa Gulch will be the ambient standards. This is not the case. If and when the ultimate standards for Arequa Gulch discharges are relaxed, the Division should re-visit the issues raised by the operator. 2. CC&V argue in their May 2 Letter that upland diversions, bactericides, and alkaline amendments are either too expensive, impossible to install or implement, will have no effect, or will not be necessary. It does not negate the Division's opinion, however, that the ore and 2