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~) CONTACT TESTS Regazding the "contact tests, the results indicate problems in two azeas: sampling methodology and analytical results. Sampling methodology: Because samples for "contact testing" were taken from depths of 8 to 14 feet, the results should not be applied to any material taken from depths greater than the depths that were sampled. If CC&V is utilizing materials from deeper reaches, those should be tested prior to application unless a demonstration of homogeneity can be made. Analytical Results: Surface Water. Cyanide exceeds primary drinking water standards in one case, and surface water standards in all six cases. Based on a hazdness of 400, metals concentrations including As, Cr, Cu Fe, Pb, Ag and Na exceed surface water standards. Analyses of Zn and Ni were conducted using detection limits too high to be evaluated. Measurement of pH, a surface water standard, was not conduced. Analytical Results: Groundwater. Cyanide exceeds primary drinking water standards in one case. All of the six measurements exceed primary drinking water standazds for nitrate (as N). Five of the six samples exceed primary drinking water standards for fluoride, and all exceed agricultural standards for fluoride. None of the samples have reported pH values, which is required for primary drinking water standards. Sulfate, a secondary drinking water standazd, was exceeded. in all six samples. Total dissolved solids exceed ambient water quality as defined by samples from the Carlton Tunnel discharge. Summary. Based on the analytical results from the Contact Tests and the high incidence of surface and groundwater quality standards exceedances, the Operator should not be applying Pad 2 materials to places where runoff will reach either surface or groundwater in concentrations typical of the analytical results. Alternatively, the material could be treated to remove the contaminants. OTHER NOTES 1. P. 3. The Operator disagrees with conclusions provided by the Division in our letter of May 30, and states that the Division agreed with the Company's position at the May 28 meeting. This is not true. The Division stands by our interpretation stated in the letter. 2. P. 3. The operator provides certain "pertinent" water quality standards applicable to Arequa Gulch and states that the pazameters and standard values are part of a mutual understanding between the Operator and the Division. The Division hazbors no such mutual understanding. 3. P. 3. The Operator states that the "pertinent" standards applicable to Arequa Gulch are for pH, CN, NH„ NOZ and C12. This is not the Division's understanding, as explained above.