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TR-38 PRELIMINARY ADEQUACY REVIEW <br />1. The NWCC report was submitted as a "stand-alone" document for insertion in a <br />permit attachment. The report contains consultant recommendations concerning <br />further monitoring, evaluation, and possible remediation approaches. However, <br />the submittal did not provide commitments and schedules from SCC, other than <br />the generalized cover letter reference to submit "follow-up recommendations and <br />plans ...once the remaining evaluations and assessments have been completed". <br />Please provide the Division with commitments addressing the proposed <br />schedule of monitoring, data collection, and additional field investigation, a <br />specific schedule for submittal of remediation plan designs (designs to be <br />provided within a future TR application), and proposed schedule for <br />construction of any approved remediation measures. This information <br />should reflect the findings and recommendations of the NWCC report, but <br />should be presented as SCC permit commitments, within appropriate permit <br />narrative or attachment sections, separate from the NWCC report. <br />2. The application did not specifically address the measures that have been or will be <br />taken to ensure both short term and long term sediment control compliance for the <br />Pond 12 watershed, as specified in the NOV CV-2008-001 Abatement Step No. 2. <br />We are aware that certain "on the ground" and permitting steps have been taken to <br />address these issues, including completion of a sediment survey for Pond 12, <br />construction of new Pond 12A, and inclusion of proposed sediment control plan <br />modifications in TR-37. We are also aware that the final sedimentation control <br />plan for the Pond 12 watershed may be modified in the future, depending on the <br />details of the final slide remediation plan. <br />Please address "short and long term sediment control measures for the Pond <br />12 watershed" for insertion in the permit, along with the scheduling <br />commitments requested in Item 1, above. Include references as appropriate <br />to pertinent sediment control plan maps and details (approved and "under <br />review"), as well as measures that have been implemented in the field. <br />3. The Division is concerned that the additional data anticipated this spring may not <br />be sufficient to allow for completion of the required analysis and mitigation. <br />Four of the eight test holes drilled between June 30`h and July 2' d, 2008 were <br />"cased with slotted and solid 2-inch diameter PVC pipe so that groundwater levels <br />and soil movements could be monitored after the drilling was completed." The <br />other four holes caved in, and test pits were backfilled. None of the four cased <br />holes had exhibited slide movement as of the time the report was submitted, <br />meaning that we do not yet know the location of the failure plane of the slide. <br />This information, as well as observations of groundwater and surface water <br />movements will be critical to developing remediation plans for the slide.