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Inadequate Support of Conclusions• Required Levels of Detection In the November 1, 1994 memorandum, Dr. Posey states that "Part of CC&V's conclusions, and procedural decisions depending upon those, aze not supported by the data disclosed. CC&V was cautioned to analyze the humidity cell leachates with an eye toward surface water quality standards. Required detection levels should have been at or below water quality table value standazds. In general, this was not done." Dr. Posey does not provide any information that demonstrates that the information submitted by the Cripple Creek & Victot Gold Mining Company ("CC&V") does not support the conclusions reached in CC&V's submission of October 7, 1994. I will repeat the Executive Summary of that submission below for convenience and clarity. (Dr. Posey succinctly summarized the Summary at the bottom of the first page of his memorandum.) If there aze specific conclusions and proposals in the CC&V submission regarding the approach CC&V has proposed to manage excess overburden that aze not supported by the report and these aze identified by the OMLR and accompanied by specific recommendations from Dr. Posey for data that aze needed to support the conclusions, CC&V will strive to obtain those data. "Executive Summary "Data for humidity cell tests performed on representative samples of the various rock materials to be excavated from the Cresson Mine are reported. The humidity cell data indicate a future tendency of certain of the rock types to produce, in the laboratory tests, acidic waters and some sulfate anions. Concentrations, nonetheless, approximate those of ground water and surface water currently found in the immediate area. In fact, testing, using the meteoric rinsate methods of hydrogen ion and sulfate testing of underground development rock from historic mining indicates an identical tendency. This tendency, which is the production of moderate pH dischazges, arises from low concentrations of sulfur-containing minerals, almost singularly pyrite, which occur naturally in concentrations ranging from almost 0 (zero) to 1 percent in the majority of the samples and from 2 to 3 percent in the most sulfitic rocks. As a result, there is historically localized lowering of pH and concurrent increase in sulfate in certain baseline ground water and in the spring in Arequa Gulch (Station AG-1). Such waters also have slightly elevated levels of zinc (on the order a few parts per million). However, the Cripple Creek Mining District as a whole does not produce abnormal water quality for this terrain within the volcanic caldera, or diatreme. The water generally meets primary drinking water standazds. "Given the lack of adverse impact on water quality created by the last 100 years of mining in the District, excavation and replacement of additional rock materials by the Cresson Project is not anticipated to adversely modify the 2