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<br />D. Surface and Ground Water Monitoring <br />As a result of Technical Revision No. 13, approved March 27, 1995, all <br />ground water monitoring of the Rimrock site has ceased. The Division <br />finds that the mining operation has had no diminution of or degradation [o <br />the groundwater quantity or quality. Ground water monitoring well 29-4 <br />was sealed in compliance with Rule 4.07.3 in June 1995. (4.05.13(1)); <br />2. The applicant will conduct monitoring of surface water in a manner <br />approved by the Division. The monitoring plan was submitted under <br />2.05.6(3)(b)(iv) and includes the following (4.05.13(2)): Sediment pond <br />discharge shall be monitored and sampled in accordance with requirements <br />of the NPDES permit. Flow rates, field parameters and lab analyses aze <br />included. One flow event per quarter will be sampled in Engleville Gulch. <br />Parameters to be analyzed for are included in permit appendix No. 4. <br />(Permit Section 2.05.6.3.2) <br />IV. Topsoil <br />Baseline soil information is presented on pages 2.04.9 (1-5) of Volume I and Exhibits <br />(G) and (H) of Volume II[. Information regarding topsoil removal and storage is <br />provided on Sections 2.05.3(5) and 2.05.4 of the permit application Volume I. The <br />two major types of soil at the Rimrock mine are the Ayon and Capulin Groups. The <br />A and B horizon soil types from each soil group were sampled and analyzed by the <br />Colorado State University soil testing laboratory for pH, texture, Iron, Copper, <br />Calcium, Magnesium, Sodium, Zinc, Phosphorus and sodium adsorption ration <br />(SAR). <br />The A horizon averaged 6 1/4" in depth in four test locations. Since IS" of topsoil is <br />required for reclamation, the Division has allowed the operator to salvage all of the A <br />and B horizons of the Capulin soil and the A horizon of the Ayon soil. In addition, <br />soil in ephemeral drainage bottoms which averages up to 60" deep will be salvaged. <br />The addition of the drainage bottom soil, which is considered to be suitable topsoil, <br />will be sufficient to satisfy the IS" topsoil cover required for the reclamation. This <br />translates into approximately 10,775 cubic yards of Ayon soil and 32,260 cubic yards <br />of Capulin soil plus streambed soil. <br />Since the operator stripped only 1 l/2 acres at a time and hauled it directly to <br />backfilled areas, only one topsoil stockpile was condwcted, located northeast of the <br />pit area (Exhibit KK). Due to the fact that mining did not progress into or east of <br />Engleville Gulch, the quantity of topsoil salvaged was less than anticipated. All <br />topsoil salvaged was, however, replaced on the backfilled and regraded areas. The <br />Division conducted an inspection on November 12, 1994 and verified topsoil <br />17 <br />