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<br />Peak Project Management, LLC <br />34115 County Road 20.8 <br />Trinidad, CO 81082 <br />RECE11/~E® (719) 846-4975 <br />SEP 13 2004 <br />Uiuision of Minerals and Geology <br />September 10, 2004 <br />Mr. Kent Gorham <br />Colorado Division of Minerals & Geology _ _ _ _ _ __ __,__ _ <br />- 1313 Shermah Street,-Room 215 <br />Denver. Colorado 80203 <br />Re: Lorencito Mine: Permit No. C-96-084 <br />Update on Maintenance Work <br />Dear Mr. Gorham: <br />Thursday I checked on the progress at Lorencito to determine the work completed and remaining to return <br />the surface drainage control facilities to their pre-100-yr 24-hr storm event status. The water levels in all <br />six ponds are now at or below their lowest weep holes. All culverts are fully open and any erosion damage <br />at the discharge ends has been mitigated. Ditches have been cleazed of major obstructions and breaches <br />have been repaired. <br />Ponds <br />The Pond 5 spillway was repaired. Damage may have been caused more by high water in the main Cow <br />Canyon drainage than from discharge over the emergency spillway. Pond 5 was inaccessible immediately <br />after the storm event but appears to have discharged. Minor erosion on the west embankment may have <br />been caused by pond out flow and still needs to be repaired (a couple of minor gullies 6-12" deep). <br />Pond 6 discharged only through the primary spillway. It was not discharging the next morning and was not <br />sampled. No work on this pond was required. Sediment had accumulated in the east ditch leading to the <br />pond. This has been cleared. <br />Pond 7 discharged over the emergency spillway. Rip rap that had shifted has been reorientated to maintain <br />good flow characteristic. No other work is needed. <br />The Pond 8 water level is 4" below the lowest weep hole. The erosion damage to the embankment outslope <br />and emergency spillway have been repaired. Rip-rap in the emergency spillway has been adjusted [o <br />promote better flow characteristics and the top surface of the embankment leveled (raised 2-4" in the area <br />above the primary discharge flume). _ <br />Pond 9A required no work. Water level is well below the lowest weep hole. <br />Repair work needs to be completed at Pond 9. The pond is dewatered to the lowest weep hole. It appears <br />that sediment has accumulated almost to the elevation of the lowest weep hole. This newly accumulated <br />