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In the Preliminary Adequacy Review Letter (PAR) of May 8, 1981, the Division <br />requested additional geologic cross sections and lithologic logs in order to <br />characterize the geology of the entire permit area, and particularly areas of <br />potential influence on the surficial aquifer. The information was submitted <br />by the applicant and has been incorporated into the application. <br />The PAR requested that an analysis of the "D" coal seam be submitted and <br />specified that both the "D" seam and "E" seam analyses should include percent <br />organic, percent pyritic, and percent sulfate sulfur. The "E" seam roof, <br />floor and coal sulfur analyses were submitted in the May 8, 1981 application <br />revision, and are listed in Table 2.04.6(2>(a)(iv)(D) of the application. The <br />Division further requested physical and chemical analyses of roof and floor <br />material associated with the "D" seam. The required information was included <br />in Appendic A of Volume 10 of the application, submitted November 23, 1983. <br />Analyses of roof and floor material associated with the "E" coal seam and <br />analyses of underground development waste which has been exposed to the <br />atmosphere indicate suspect SAR values. SAR values above 20 were reported in <br />both cases (see pages 67a-69 of Volume 10, and Table 2.04.9(1)(b)-4). The <br />applicant proposes to cover all underground development waste material with 4 <br />feet of non-toxic cover and topsoil. Analyses of "D" seam roof and floor <br />material contained in Volume 10 do not indicate acid-forming, sodic, or <br />otherwise inhibitory strata. <br />Pre-law surface mining activity in and adjacent to the surface facilities area <br />at Red Canyon has resulted in a mixing of geologic material, with piles of <br />overburden left adjacent to small mining and exploration pits. Previously, <br />Grand Mesa has filled in the abandoned strip pits with underground development <br />waste, and proposes to cover portions of the waste with material from the <br />abandoned overburden piles. During this five-year permit term, the applicant <br />proposes to expand the refuse pile onto previously undisturbed slopes to the <br />east of the facilities area. Additional non-toxic cover will be obtained from <br />subsoil and overburden stripped prior to placement of refuse. <br />Drawing 2.05.3(9)-2 contains refuse area cross-sections which indicate that <br />sufficient material will be available to provide a 3.5 foot refuse cover. The <br />total area extent of exposed coal waste which will require cover is <br />approximately 12 acres. The entire "refuse area", which includes the <br />overburden piles and existing and proposed portions of the underground <br />development waste pile, totals 20.28 acres (Table 2.05.3(5)-1), approximately <br />8 acres of which is overburden storage. The entire area will be graded and <br />revegetated as a part of final reclamation. <br />Subsoils at Red Canyon are clayey and slightly saline, and the overburden <br />proposed as non-toxic cover exhibits similar qualities (Table 2.04.9(1)(b)-4, <br />Site No. 0-6 and 0-7). The material is clay, with one EC value of 5.6 (0-7). <br />SAR values are very low and pH is moderate. The material is suitable for <br />non-toxic refuse cover (see also C.S.U. soils analytical evaluation, Figure <br />2.04.9(1)(d)-1). <br />The proposed operation is in compliance with the requirements of this section. <br />-13- <br />