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<br /> <br />alkaline rock has been placed below the waste rock, or that such rock, if placed, has an adequate <br />amount of alkalinity to neutralize any excess acid. Furthermore, the Division also has not <br />received adequate information to know whether lime has been added to the high sulfur waste <br />rock disposal areas. <br />Section 10.2 of the permit stipulates that waste rock with less than 0.8% sulfur will be placed <br />in the Arequa Gulch or Victor overburden storage areas, only. Verification of the sulfur content <br />of the waste rock in these areas has not been received. <br />The Operator has noted (L.etter from J. Hardaway to B. Keffelew, Oct. 26, 1996) that waste rock <br />in the Arequa Gulch overburden storage azea has an "average" sulfur content of less than <br />0.1447% sulfur and that the "average" sulfur content of waste rock in the Iron Clad and Globe <br />Hill pits is 0.7993%. Averaging the sulfur content of the waste rock was not discussed in the <br />permitting process, and is not a condition of the permit. Furthermore, there is no evidence that <br />such a method will provide groundwater and surface water protection either from acid or from <br />dissolved metals. The Division, thereby, maintains that any standard mining unit having greater <br />than 0.H% sulfur is to be amended with lime, and that no standard mining unit having greater <br />than 0.8% sulfur is to be placed in the Arequa Gulch waste rock storage area. <br />Review of rock leaching data shows there is no direct correlation between percent sulfur and the <br />amount of dissolved metal. Therefore, blending high sulfur rock with low sulfur rock in order <br />to reach a composite average of 0.8% sulfur or less is not considered a valid assumption in <br />regazds to minimizing impacts to the hydrologic balance from dissolved metals. <br />Considering the observations identified above, the Division requires the following: <br />1. Within 15 working days of receipt of this letter, please fumish to the Division verification <br />that no waste rock having a standard mining unit content of 0.8%a sulfur or higher has <br />been placed in the Arequa Gulch overburden storage area. <br />2. Within 15 working days of receipt of this letter, please furnish to the Division verification <br />that all waste rock having a standard mining unit sulfur content of 0.8% or higher sulfur <br />has been amended with lime. Please indicate the amount of lime added to each unit. <br />3. If verification of either of the above two conditions cannot be furnished, please provide <br />adequate evidence that the waste rock has been placed in a manner whereby effluent from <br />the waste rock will be able to meet table value standards for surface water, and will be <br />able to meet groundwater conditions established by the Division, i.e., discharge standards <br />for the Carlton Tunnel. <br />Please be advised that the Division considers the above topic to be a troublesome matter. We <br />believe it is in the best interests of the operator and the public to get this matter resolved as soon <br />as possible. We trust that we can expect your full cooperation. <br />2 <br />