REV13408 - Laserfiche WebLink

Home Browse Search

observations shall be conducted starting as soon as slopes are suitable and shall be made over a minimum of 6 months. The observations shall be of slopes placed at the angle of repose and as long a slope (crest to toe) as is planned for the Project. If the observations show that the ten- footdistance is not needed to control ravelling, maintaining the distance shall not be mandatory. Those currently existing areas where the toe of the outslope may be less than 10 feet from the edge of the liner, other than roadways, will be identified by CC&V on a map and in writing. Backfilling of Mines: CC&V has obtained clarification from the OMLR that the questions related to backfilling were based on a concern that such backfilling would result in surface water outflow from the mine without proper planning for that outflow. CC&V, therefore, agrees that any backfilling of mines, except that conducted at the Globe Hill and Ironclad Mines, will be limited to that which does not raise the level of the backfilled surface to or above the elevation(s) that would cause surface water runoff from the backfill to flow past the outline of the mine excavation, unless an acceptable drainage plan is submitted to the OMLR. CC&V has reworded the statement provided in response to item No. 3 in its November 11, 1998 letter to the OMLR to read as follows: "CC&V has been required to not backfill new surface mined areas with significant amounts of materials subject to the following criteria: CC&V will continue to backfill the former Ironclad and Globe Hill Mines. CC&V also is authorized to place overburden into surface mines in a manner than does not raise the elevation of the backfilled material to or above the elevation(s) that would create the potential for surface water to run off to areas outside the boundaries of the mine excavation unless asurface-water drainage plan for the runoff has been accepted by the OMLR. Slope Requirements for Overburden Storage Areas: CC&V wishes to add the following to summarize and clarify the post-mining, reclamation slopes for reclaimed lands on Overburden Storage Areas: "The reclaimed slope on the northeast side of the Arequa Gulch Overburden Storage Area will not exceed 2.OH:1.OV and the reclaimed slopes of the Squaw Gulch and the remaining slopes of the Arequa Gulch Overburden Storage Areas will not exceed 2.SH:1.OV. Reclaimed slopes will be graded so as to achieve a stable landform that meets the post-mining land use(s)." Generalized cross-section diagrams of slopes that meet these requirements for the 2.SH:1.OV criterion are provided as Attachment 1. Post-mining highwall berms: For simplicity, CC&V has agreed that the most suitable post- mining protection around the crest of mine highwalls that have not been backfilled is an earth berm. CC&V agrees that these betms, when required to provide a barrier to trespassers, will be constructed as shown in Attachment 1 to CC&V's letter of November 11, 1998 ("Design 2