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INTRODUCTION <br />•' During the heavy spring runoff of 2011, the Yoast Mine reclaimed areas experienced numerous <br />new and reactivated landslides, slumps and mudflows. A site visit and meeting was held on July <br />6 and 7, 2011 with Jill Carlson (Colorado Geological Survey), Sandy Brown (DBMS), Susan <br />Burgmaier (DRMS), Brian Len (NWCC) and SCC personnel to discuss and identify areas of <br />instability. SCC has prepared the following documentation to: 1) indentify unstable areas within <br />the disturbance boundary; 2) document present conditions of each area; and 3) present a <br />remediation plan/approach for each area. This proposed plan is based on a report prepared by <br />Jill Carlson (CGS), the report is attached for reference. <br />0 <br />AREAS TO BE REPAIRED /STABILIZED <br />• Neck Pit Slide <br />— Problem: This is a large rotational surface failure in an un- mined area. Minot fill was <br />placed during reclamation to reduce the road grade through the area, but the width of the <br />slide area is much wider than the area that received the fill indicating that the 2011 slope <br />movement cannot be specifically attributed to mining activity. Toe bulges have caused <br />road damage. <br />Remediation: Regrade the head scarp; install trench drains to reduce water saturation and <br />reseed the area. <br />Status: Work has been initiated and will be completed in 2012. <br />• Pond 012 Slide Area <br />— Problem: This was a large unstable slope on the north side of the pond that encroached <br />on the pond and the drainage channel above the pond. <br />Remediation: The slide area was excavated and reconfigured according to an approved <br />remediation plan <br />Status: A majority of the work has been completed, but final completion was delayed <br />during the winter of 20011/12 at the recommendation of the Division for further <br />observation in the Spring. Once acceptable stability has been achieved final grading, <br />topsoil replacement and reseeding will be completed. <br />• Pond 013 Slide Area <br />Problem: The slide is situated on or near a final pit highwall and access road ramp. The <br />slide are contains disturbed and undisturbed area on a steep side slope. The slide <br />continues to move as it reaches equilibrium and has partially blocked a permanent <br />drainage channel. <br />During the latest inspection, SCC learned that the area was historically mapped as <br />containing a mud flow, landslide deposits and generally unstable slopes (Madole, Colton, <br />TR -51 20 -2.1 11 /I1 <br />