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the operations conducted at the Hamilton Mine. Also, the methods used to backfill the spoil provided <br />for the mixing of the spoil to increase neutralization. Overall, should a spoil spring develop in the <br />future the impact is expected to be negligible. <br />The dry climate (12 inches annual precipitation) and the relatively small land area above Hamilton's <br />backfilled pit (59 acres), indicates a very low probability of a leachate plume forming down - gradient <br />from the pit. Further there were no water - bearing bedrock units in hydraulic communication with the <br />pit. There are several domestic wells within two miles of the disturbed area. The mine was situated <br />on top of a mesa overlooking Naturita Creek. The mine extended into shallow Dakota Sandstone but <br />did not intercept an aquifer. Given this, there is no potential for impacting domestic well water users <br />in the area. <br />Surface Water Impacts <br />Surface runoff from the proposed permit area flows north into Naturita Creek along Section 33 <br />Creek. Runoff also flows west to Bramiers Draw which terminates in the San Miguel River less than <br />one quarter mile below its confluence with Naturita Creek. Stream flow across and adjacent to the <br />permit area is ephemeral, resulting from snowmelt and storm activity only. Review of available <br />monitoring data and given the overall lack of surface water present at the site, the Division concludes <br />that there have been no impacts to surface water in or adjacent to the permit area resulting from the <br />Hamilton Mine operations. <br />Six surface water sites were monitored this year. Two monitoring sites are located in Bramiers Draw <br />to the west of the disturbed area; B -1 Upper Bramiers Draw, B -2 Lower Bramiers Draw. B -1 and B- <br />2 were reported as being dry since 1991 to when monitoring was suspended in at the end of 1998. <br />Each time the site was monitored in 2012, they were reported as dry. Another two monitoring sites <br />N -1 Upper Naturita Creek and N -2 Lower Naturita Creek were monitored twice in 2012. The sites <br />were dry when monitored in September, but they were flowing in the spring. The data collected at N- <br />1 and N -2 during the spring does not indicate the site has been impacted by the mining operation. <br />Monitoring site H -2 Lower Broad Creek appears to have flowed intermittently since monitoring was <br />initiated. This site was reported to be dry during 2012. Monitoring site S -1 Section 33 Creek was <br />reported to by dry each time the site was monitored since 1991. Overall it does not appear there is <br />evidence the surface water has been impacted by the mining operation at these monitoring sites. <br />During the mining and reclamation, surface water was routed through two sedimentation ponds, Pond <br />A and Pond B. Pond B was approved to be left as a permanent impoundment in accordance with <br />Section 2.05.3(4) of the permit. Exhibit 8 of the permit includes letters from the landowners who <br />wish the impoundment to be left in place and approval from Montrose County and the Division of <br />Water Resources. Pond A was reclaimed in 2010 as indicated in the Phase II observations section, <br />this pond was reclaimed in accordance with the permit and Rule 4.05.2(2). Based on the discharge <br />monitoring reports submitted to the Division, it does not appear water discharges from the site has <br />impacted the hydrologic balance. On August 9t', 2012 the Division received documentation from the <br />Operator that the Colorado Water Quality Control Division approved the termination of the Colorado <br />Discharge Permit (COG850024) for the site. <br />Page 14 of 16 <br />