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reclaimed since the implementation of the interim regulations. Some geologic <br />surface modeling software is capable of delineating areas steeper than. specified <br />grades. Since photogrametic data is available for the reclaimed topography, if <br />accurate, this can be used instead of the transects. All areas must meet the <br />approved plans. <br />5. Prior to bringing in the heavy equipment for additional grading, those areas <br />that need work should be surveyed and marked on the ground as well as on a map. <br />This should be submitted to the Division with a description and maps showing the <br />additional work necessary. <br />6. The Division is concerned that ditch B-2 and the associated benching that <br />traverse the backfilled west highwall at the 720 pit may require extensive earthwork <br />to reclaim after it is no longer needed. Also, this ditch is costing backfilling <br />resources to maintain this bench. The Division is concerned that this is more trouble <br />than its worth, especially south of the 720 pit highwall notch. Also, there are even <br />longer slopes north of the location where this ditch turns east that do not benefit from <br />this ditch (see page 3 for more detail). Is it feasible to remove this ditch? If so is <br />pond A large enough to accommodate the extra drainage? The final drainage <br />control imprint must be in place prior to phase I release. This includes all comments <br />made on page 3 of this report. <br />Hydrology <br />7. During the inspection, the operator mentioned that a geo-textile would be used <br />to line steep slope drainage channels. This should be submitted as a (MR, TR <br />Dave?) revision with supporting calculations. <br />8. Erosion was noted in the drainage channel above pond A. Sections were <br />noted to have grades of 6% and 8%. The operator said that these grades will be <br />lessened during final grading. What will the maximum grade for this channel be, and <br />will this area require suitable channel protection? Proper riprap installation may be <br />preferable. <br />Slope Stability <br />9. Numerous settling cracks were noted along the backfilled highwall of the 720 <br />pit. The Division feels that a slope stability analysis should be done to assure that <br />there is a sufficient safety factor. <br />Overburden Geochemistry <br />10. The permit calls for sampling for overburden toxicity in the reclaim areas. <br />Samples have been taken by the operator but results have not come back from the <br />lab. The Division wishes to see the sampling results when available and would like <br />Marr Strip, Bond Release 6 May 24, 1994 <br />