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<br />acreage in, and around, [he limestone and dolomite areas. <br />7) Rule 6.4.4 -the DMG asked that the method of erosion control be adequately described in this <br />document (construction details, specifications for compaction, drop tube or spillway size, etc.). <br />Sifting through your response, I concluded that you intend to construct "A berm of at least three <br />foot in height and graded to 3:1.." "to prevent run off from the pad entering the stream." If a <br />significant precipitation event occurs, runoff will either pond up somewhere along the berm (and <br />possibly enter the stream) or the water will overtop the berm and enter the stream. Since ponding <br />seems most likely, you intend to construct a "decant pond." You state in your response that <br />"When I have the mapping done I will have the area of the siltation pond determined." No <br />information regarding the siltation pond was submitted with your latest response except for a <br />notation on the maps fora "drainage decant pond" and a "potential decant pond", along with the <br />approximate area of each pond. <br />In order to ensure that the decant (sedimentation) ponds are adequately constructed, the volume <br />of runoff from the 2 year 24-hour storm event reporting to the pond(s) needs to be approximated. <br />You provided information regarding the 2 year 24-hour event. You reported that the amount of <br />precipitation for this event equals 1.6 inches. You also say that the total amount of rainfall for <br />this event equals 26.67 acre feet. How did you calculate this number and is this the amount that <br />will flow to the decant pond? <br />If 26.67 acre feet of runoff is the estimated volume of water reporting to the decant pond then the <br />facility must be adequately constructed to contain this amount of water. Also, the facility must <br />contain an outlet (spillway, drop tube, culvert, etc.) that will adequately convey excess runoff <br />during precipitation events that exceed the designed storm event. Design criteria for the outlet <br />must be submitted to the Division for approval. <br />The blasting analysis (by Henkle and Associates) you submitted was incorrect because it did not <br />include Ms. Brown's structure. Since I sent you the wrong report, I inserted the correct blasting <br />report in your packet and have enclosed a copy for your files. Also, enclosed is a copy of a DMG <br />letter, dated October 3, 1997, which outlines a condition which is expected to be included in this <br />application involving pre-blast surveys of Ms. Brown's structure and potential flyrock problems. <br />Do not send the DMG letter. Include the pre-blast surveys and resolution of potential flyrock <br />problems in your response to this adequacy letter. <br />8. Rule 6.4.5 -the proposed post-mining land use for this operation is Wildlife Habitat. How will <br />the existing buildings/structures, or newly constructed buildings, benefit wildlife if they aze to <br />remain on site after mining ceases? You state in your February response that the crushing tipple <br />has historical value and that it should remain. The Division agrees. However, you also state that <br />"any structure that might be constructed to house and maintain equipment would remain if it <br />would facilitate a recreational use." Normally, wildlife habitat and recreational uses are not <br />compatible. <br />The proposed application does not address construction of new structures buildings. If new <br />buildings/structures are being proposed, you will need to provide construction specifications, <br />locations and whether they comply with local building and zoning codes. Also, final status of the <br />buildings will need [o be addressed. <br />