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• > ~~~ <br />4. P. 3. The Operator states, incorrectly, that the water quality standard for Arequa Gulch <br />is 4.0 to 9.0. <br />5. P. 3. The Operator states, incorrectly, that an average concentration of 0.098 mg/L CN <br />based on 72 hour D.I. contatt tests meets water quality discharge standards. Samples of <br />shallow material cannot adequately represent the degree of pad detoxification. Deeper <br />samples must be tested if they are to be used on or off site, and all azeas (not the average of <br />azeas) must reach the Division's detoxification criteria of 0.2 mg/L WAD cyanide. <br />6. P. 4. Based on consultation with the WQCD, the Division have concluded that the <br />Operator's application of proposed ammonia standards to compliance is wrong. <br />7. P. 4. The Division stands by our original statement regarding chloride concentrations. <br />8. P. 4. The Operator's interpretation that there is not a point source discharge from the mine <br />materials referred to appears to be in direct opposition to interpretations made by the <br />WQCD. The Operator is advised to azgue their position to the WQCD. Meanwhile DMG <br />must accept the interpretations of the WQCD rather than the Operator. <br />9. P. 4. The Operator reiterates that some agreement was reached at the May 28 meeting <br />between them and the DMG that "temporary modifications" aze the applicable standards for <br />Arequa Gulch and that the temporary modification "rules" because it refletts ambient water <br />quality. The Division did not agree with this position, nor with the position that <br />measurements taken azound AG 1.5 represent "ambient" conditions, in the legal sense. <br />The Operator should recognize that cyanide measured at the AG 1.5 station comes from any <br />of three possible sources: the Carlton tailings, leaks from Pad 2, leaks from Pad 1, or any of <br />the downstream collection ponds. Thus, ambient criteria could not be applicable. The <br />Operator is to be cautioned that relocation of Pad 1 or Pad 2 waste to Arequa Gulch, where <br />it will drain into the Arequa Gulch underdrain, will not relieve the company from meeting <br />water quality standards. <br />10. P. 5. The Division anticipates that all future data reports will be accompanied by laboratory <br />verifications. This is considered a normal part of quality assurance, and should be instituted <br />by the company as standard prattice. <br />SUMMARY <br />Geochemical measurements based on Contact Tests of the Pad 2 ore exceed applicable standazds for <br />both surface and groundwater. Fluids passing through those materials and carrying metals or <br />cyanide in proportions represented by the Contatt Tests must be protetted from direct discharge <br />to either surface or groundwater. Otherwise, the materials should not be used for the purposes <br />proposed, and in the manner already in effect at parts of the mine. <br />