Laserfiche WebLink
RGRASSYSCREEK MINE ~~~~~~~® <br />ADEQUACY RESPONSES <br />TO CMLRD 9/13/91 COMMENTS NOV 2 6 1991 <br />OCTOBER, 1991 Mtned Land <br />Reclamation Division <br />PI <br />1) Please submit the !rand-drawn topography maps, derived by ACZ so that we <br />may evaluate the hydrologic design calculations jot Pits 5 and 6. The map <br />should be su6mitred in some type of fonnal format, and it should be <br />certr~ed as being a reasonable approximation of existing topograplry. A <br />more detailed map is not being required. Hand drawn maps will not be <br />used ro assess achievement of approximate original contour. <br />Response: Neither survey nor aerial photogrammetric documentation <br />is available to map the current configuration of Pits 5 and 6. <br />Postmining drainage designs for these areas are based on a hand- <br />drawn map developed through interpretation of existing surface <br />features, typical slopes, and blending with known contours on the <br />perimeter of disturbance areas. The hand-drawn representation of <br />current Pit 5/6 topography has been inserted into the most current <br />Rockcastle base to develop the Postmining Drainage and Sediment <br />Control Map, (Map R-1) which accompanies these responses. This <br />map includes an appropriate certification noting the source of mapping <br />information. <br />2) The previous submittals proposed permanent retention of all upland <br />diversion ditches at Pits 5 and 6. Retention of upland diversion ditches is <br />not consistent with the regulations, and does not constitute a maintenance <br />free reclamation configuration. As such, we requested a revised engineering <br />plan far Pits S and 6 wl~iclt plans for elinrination of all upland diversion <br />-1- <br />