Brushy Fork Stage 10D To 10F Proposed Stability Analysis

This Revision is proposed for two (2) purposes.  The first  area covered by this revision is the inclusion of Stability analyses for Stages 10D and 10F.  Previously, applications were submitted for Stages 9A through 10F, and the facility was approved through Stage 10C with a design crest elevation of 2090 feet.  Final approval for stages 10D through10F, has been postponed due to the development of excess pore pressures beneath portions of the upstream embankment in 2009.  Before final approval can be granted, an evaluation of slope stability is needed for Stage 10F that considers excess pore water pressures.  Accordingly, Stage 10F stability analyses have been included herein for review and approval of the facility to continue through Stage 10F.  Refer to attached Stability Analyses prepared and certified by Geo/Environmental Associates, Inc.

Additional precautions are proposed herein to address the pore pressures, but to allow for continued refuse placement so that the operation is not shut down.  These precautions are addressed in detail in the attached letter from Geo/Environmental Associates, Inc., “Response to MSHA Comments Stages 10D through 10F”.

Updated plan drawings are included as well which show  the proposed additional measures as contained in said letter.

No other revisions are proposed herein.