Laserfiche WebLink
<br />c) Currently no ditches are shown on Map 16a along the southern <br />permit boundary to prevent water from draining into the tributary <br />of Bolton Draw prior to treatment in Pond A. If there are no <br />drainage structures here, make the appropriate demonstration for <br />a small area exemption per Rule 4.05.2(3). <br />RESPONSE <br />In this question, the Division expresses concern regarding <br />drainage along the southern boundary along the 120 Pit. <br />Review of the Current Mine Area Topography Map (Map R90-1) <br />submitted in conjunction with permit renewal on November 8, <br />1990 indicates that all drainage from this area currently is <br />captured by the 720 Pit. Additionally, review of Map 37a, <br />Kerr Mine Area Postmining Topography, indicates that all <br />drainage from this area will be collected by permanent ditch <br />PD-2 and routed to Pond A prior to release to the tributary <br />to Bolton Draw. Accordingly, there is no need for any <br />diversion ditch in this area since all drainage is currently <br />and will in the future be contained within the permit area <br />and/or treated in Sediment Pond A prior to release from the <br />permit area; no small area exemption demonstration is <br />necessary and no other responses are required since this area <br />is in compliance with regulatory requirements. <br />d) There needs to be a culvert to carry water from the east side of <br />the 720 overburden stockpile into Pond B across the pond A access <br />road. This road is used frequently enough that Kerr should <br />utilize best management practices to minimize disturbances to the <br />hydrologic balance by installing a culvert. Please design an <br />appropriately sized culvert and submit a schedule for its <br />installation. In conjunction with this drainage calculation, <br />design a ditch to carry the water in a non-erosive manner to Pond <br />D. <br />RESPONSE <br />An appropriately size culvert has been designed to carry <br />water across the Pond A access road adjacent to the 120 <br />overburden stockpile into Pond B as requested by the <br />Division. Although this road is used very infrequently and <br />is avoided when wet, Kerr has elected to prepare the <br />appropriate design as requested. The culvert design <br />indicates that an 18-inch CMP is necessary. Alternatively, <br />since this road is used only to access Pond A for water <br />monitoring purposes, Kerr may elect to pace 9lanking across <br />~ ~f f~, ~~ ~C } ~ <br />2 5 ctiC+~ <br />