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either straighten or remove the damaged casings. The effort failed; SCC was able to get a <br />variance from the State Engineer's office from their abandonment requirements because it <br />was not possible to run tremmie pipe down to properly abandon them. Pond 016A was built <br />in 2004, and SCC abandoned the wells in 2007. The wells were cemented in from 40' bgs to <br />ground surface but continue to flow (we believe subsurface from the point of the broken <br />casings). To rectify the. situation, SCC installed a substantial French drain to collect the <br />seeping water and direct the flow to the Pond 016 inlet which is located downstream of <br />Pond 016A dam. The site was capped and backfilled after installing the drain. Given the <br />condition of these wells, it is imperative that the abandoned wells and French drain not be <br />disturbed. Please modify the Remediation Plan to clarify that grading will not take place in <br />the immediate vicinity of the abandoned wells to ensure that repair activities do not disturb <br />the wells or drain. <br />5. The fifth full paragraph on NWCC page 5 indicates that channel PM-2 should be excavated <br />into "competent bedrock materials". Test Holes 12 and 13, which are near to the proposed <br />realignment of PM-2, are logged on NWCC Figure #2. In these holes, weathered claystone <br />was encountered at -10 feet beneath the surface, and claystone bedrock was present at 13 <br />to 17 feet below the ground level. Please provide additional information on SCC's plan to <br />ensure that PM-2 will be excavated into competent material. <br />6. Although not stated directly, the NWCC report seems to imply that relocated Channels PM- <br />2A and PM-2 will now serve the dual purposes of transport of surface water runoff and <br />interception of subsurface water that is flowing into and out of the shrub plot landslide. <br />Please verify that this is or is not the intent of the proposed plan. <br />7. Construction of PM-2 across the toe of the shrub plot landslide may contribute to additional <br />loss of stability in the slide mass due to the removal of any materials now acting as a <br />buttress. Subsequent downhill movement of the mass could encroach upon the PM-2 <br />channel and create a damming effect. Please address the possibility of this scenario <br />occurring. <br />8. The current application does not propose the construction of any ditches or channels to <br />divert surface or subsurface flow away from the eastern two-thirds of the shrub plot <br />landslide. While regrading the area is not yet feasible, would installation of a cutoff channel <br />be possible with TR-73? <br />9. Page 1 of the text states that the new road will be approximately 20 feet wide. Please add a <br />typical section for the road to this map, showing the proposed configuration for both cut <br />and fill situations, with roadside ditches and proposed surfacing material and thickness. <br />10. The Division was unable to find details with the TR-73 application that describe how the <br />road will be constructed to comply with the requirements of Section 4.03.2 - Access Roads. <br />Please provide the details and required commitments, or direct the Division to the place in <br />the current permit where these items are already addressed.