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C-81-012 New Elk Midterm. Kent Gorham 12 <br />a. Exhibit 30 is an original study for the RDA area, however, a theoretical stability <br />analysis for the Development Waste Pile cannot be located. Regardless, a new <br />stability analysis for the Development Waste Pile needs to be accomplished to include <br />a full set of laboratory tests since pond tailings are being added to the pile. The <br />addition of pond tailings can significantly alter strength pazameters as well as well as <br />other physical parameters density and compaction as evidenced by the unacceptable <br />proctor test results preformed on this pile on March 22, 1996. <br />The following recommendations orcomments listed below (a-d) are informational only. You may <br />or may not respond, as you see fit. <br />a. Permit page 2.05-51 refers to vegetative sampling for determination of reclamation success. <br />This page states that a minimum of 10 cover and diversity transects will be collected. <br />Please refer to the April 1995 DMG "Guideline Regarding Selected Coal Mine Bond <br />Release Issues", page 21. The Division recommends collection of a minimum of 15 sampE <br />observations for bond release data collection. Although Basin is not required to revise this <br />minimum data sample amount, the Division reminds Basin of the recommended statistical <br />sampling protocol. <br />b. Permit page 2.05-49 states that the operator will use straw or hay mulch. The Division's <br />experience is that when hay mulch is used, deer and elk are attracted to the newly <br />reclaimed site and rapidly remove the mulch component. The Division recommends the use <br />of Certified Weed Free straw mulch. <br />c. Due to a lack of available topsoil in the mine yard area, Basin has been approved to use <br />regraded yard material in lieu of topsoil in the East Portal facilities area. Sampling of this <br />material was conducted in July 1986 and December 1986. Results shown in table 17 <br />indicate that material found in the areas of samples 14, 15, and 16 exhibit elevated pH and <br />high SAR's. Additional amendments or topsoil importation may be necessary in those <br />location to assure vegetation establishment. <br />d. The Division has reviewed the seed mix found in Table 26. This appears to be a diverse <br />mix adapted to the site and the post-mining land uses. The Division does caution the <br />operator to use locally adapted cultivars. Some of the seed will be chaffy, Sideoats grama <br />and Mountain muhly, which will require special seeding equipment. Some seed requires <br />shallower planting depths than the majority of the seed and should be seeded at the <br />recommended depth (Sideoats grama and Blue grama). The shrub seed is recommended for <br />-12- <br />