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,. 3. The excavation and exposure of pyritic limestone and shale from the 4th Ridge area is still a concern with respect to the potential for producing acid-mine drainage and, therefore, possibly requiring a Designated Mining Operation status for the operation. It is understood that the operator has committed to removing and processing all pyritic material at the cement plant rather than stockpiling it. The Division, however, specific acid-base accounting tests to be performed on a representative suite of samples from Che pyritic 4th Ridge material to be exposed to surface water and oxidation during and after mining. In addition, the Division will require that the operator commit to a more substantial reclamation plan for the exposed pyritic limestone and shale in the 4th Ridge pit. The plan must insure that previously exposed pyritic rock is sufficiently neutralized (i.e. ripping and mixing lime in with pyritic material,...) before topsoil is placed on the material and revegetated. A minimum of 2 feet of topsoil or appropriate growth medium is probably adequate for this purpose. Perhaps the limestone fines from the cement plant could be used to effectively neutralize the pyritic pit bottom rock. The summary of chemical analyses of 4th Ridge material presented in Attachment 6 appears to be an abbreviated whole rock analysis of the rock (in percents? - no labels). This does not quantify how much Fe and S03 (sulfate sulfur) are present as sulfides which could produce acid runoff. The Division will require a quantification of pyrite content and sulfide species for the 4th Ridge material and associated waste rock to be exposed in the pit bottom (and walls?). With the appropriate data, the Division can make an informed decision as to whether the Dowe Flats quarry application should be exempt or not from Designated Mining operation status and requirements. 4. Exhibit H - Wildlife Information - In Rick Thompson's letter to SHB AGRA in Attachment 17, it is stated ' The black-footed ferret study will be conducted between December 1., 1993 and March 31, 1994 following current USFWS ferret survey guidelines.' Has the study begun and is it on track? Construction activity on site cannot begin until the Division receives and evaluates the results of the ferret survey and approves the initiation of construction activities. In the Division of Wildlife letter dated June 22, 1993 to Boulder County, it is stated that it is imperative that provisions be made for harvest of deer in the area. What are these provisions and have they been committed to by the operator? 5. Exhibit L - Reclamation Costs - Please specify the equipment type, combinations and sizes for the earthwork to be completed