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7. On Page D -5 under Item b, it is stated that the soils underlying the ore storage pad have <br />a high clay content, low permeability and limited downward mobility. Please disclose the <br />actual thickness / clay content underlying the ore storage pad. Also, have any boreholes <br />or test pits to determine the thickness of the high clay soil been completed to support the <br />claims stated above? <br />Twelve inches (30.5 cm) of compacted clay will comprise the clay liner for the <br />ore storage pile. For saturated conditions, clay typically has a hydraulic <br />conductivity of 10 E -08 cm /s. The unsaturated hydraulic conductivity for <br />partially saturated clay would be significantly less. Under a unit hydraulic <br />gradient and saturated conditions, both conservative assumptions, water would <br />only penetrate 0.03 cm during the 30 days the ore remained on the stockpile. No <br />boreholes have been drilled. Hydraulic and geochemical factors discussed in <br />length in the EPP support Cotter's position. <br />8. On Page D -5 under Item b, the applicant states that "A contractor will be used to haul <br />the ore from the surface ore stockpile area to the mill. The ore haulage contractor will be <br />responsible for a spill control plan. "Per the requirements of Rule 3.1.13 the mine <br />operator shall notify the Division of any toxic or hazardous substance, including spills of <br />petroleum products that occurs within the permit area. Please commit to the <br />requirements of Rule 3.1.13. <br />Cotter will notify the Division of any spill of a toxic or hazardous substance, <br />including spills of petroleum products, that occur within the permit area and <br />which would be required to be reported to any Division of the Colorado <br />Department of Public Health and the Environment, the National Response <br />Center, the Colorado Emergency Planning Commission, any local Emergency <br />Planning Commission, local Emergency Planning Committee, or the State Oil <br />Inspector, consistent with the requirements of Rule 3.1.13. The haulage <br />contractor will be responsible for any en -route spills occurring off -site. <br />3 <br />