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were leaking as a result of increased hydrostatic pressures as the ground water was allowed to <br />return to its equilibrium level following the cessation of pumping. <br />The backfill in front of the No. 1 Mine portal seal was excavated to expose the seal and airshaft. <br />Two valved pipes were installed in the portal seal to control the seepage and route it to several <br />treatment ponds via a French drain. The seepage water entering the treatment ponds was treated <br />with sodium hydroxide in order to increase the pH and allow the iron to precipitate before the <br />water dischazged to the creek. The treatment system was later modified to increase the residence <br />time of the seepage water in the treatment ponds. This was accomplished by elongating the <br />treatment ponds to increase their volume. The longer residence time resulted in the iron <br />precipitating out of the water, to below the NPDES effluent limits, without the sodium hydroxide <br />treatment, and chemical treatment was discontinued. <br />A plan for backfilling the No. 1 Mine portal was approved with Technical Revision No. 20 on <br />October 1, 1998. The Division's inspection of October 26, 1998 confirmed that the No. 1 Mine <br />main alit and ventilation shaft adit were backfilled, graded and topsoiled. <br />The fmal reclamation of the loadout azea included grading and backfilling the disturbed azeas. <br />The azea was returned to its approximate original contours and restored to support agricultural <br />production. The loadout area reclamation was completed in 1987. <br />The main portion of the loadout was located north and east of the Roaring Fork River on land <br />known as the Diamond A pazcel. The Diamond A Pazcel was removed from the permit by the <br />Division's approval of TR-15 on February 1, 1994. <br />Findings of the <br />Colorado Division of Minerals and Geology <br />for <br />North Thompson Creek Mines <br />Explanation of Findings <br />Pursuant to Rule 2.07.6(2) of the Regulations of the Colorado Mined Land Reclamation Boazd <br />for Coal Mining, and the approved State program, the Division of Minerals and Geology or the <br />Board must make specific written findings prior to issuance of a permit, permit renewal, or <br />permit revision. These findings aze based on information made available to the Division that <br />demonstrates that the applicant will be able to operate in compliance with the Colorado Surface <br />Coal Mining Reclamation Act and the Regulations promulgated pursuant to the Act. <br />The findings in the following sections required by Rule 2.07.6(2) are listed in accordance with <br />that Rule. The findings and specific approvals required pursuant to Rule 2.07.6(2)(m) are listed <br />in accordance with Rule 4 and aze organized under subject or discipline subtitles. <br />10 <br />