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• • <br />Memo to Steve Renner <br />Coal Basin Examination <br />page 4 <br />of an old topographic swale. I recommend that these seeps be <br />developed by excavating and backfilling them with gravel to promote <br />better drainage and decrease residence time for groundwater. This <br />should stabilize the material and help to prevent mine drainage <br />acidity problems. Finally, the small triangle of ground below the <br />newly aligned ditch should be graded to drain towards the southeast <br />and into the ditch. It will be difficult to achieve more than 1% <br />grade in this area. Hopefully by completing this combination of <br />improvements, less saturation will occur due to ponding of spring <br />melt waters in this poorly drained bog area. <br />Mr. Dulaney expressed his dismay at redisturbing the old access <br />road which he suggested had achieved the sort of natural slope <br />readjustment they believe all roads at Coal Basin should be allowed <br />to attain in final reclamation. Tony and I observed that the coal <br />refuse pile is required to have a permanent diversion. The <br />operators representatives also suggested they'd like to allow the <br />road to drain in "sheet flow" over the outslope and into Dutch <br />Creek, approximately 100 feet down its course from the disturbed <br />area. I believe this is not desirable and recommended against it <br />because "sheet flow" without a concrete pan or cleaned resistant <br />bedrock inevitably results in gully formation and increased <br />sediment generation. <br />cc: Tony Waldron <br />Larry Routten <br />Doc: M: \MIN \JAP \DUTCHCRK.WPF <br />JP /jp <br />