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• 2.05.6(6) <br />Regarding the Bruce Park Dams, the GEI Consultants Inc. report referenced <br />above concluded the main dam and saddle dam would be stable under the <br />assumed seismic loadings and mine workings within 1300 feet of the dam(s). <br />If the subsidence monitoring program shows that material damage to the <br />Bruce Park dams and/or Bruce Park landslide is occurring or is going to <br />occur, the mine plan will be amended. The edge of the mine workings will be <br />moved further away from the Bruce Park Dam and Bruce Park landslide <br />which will move the effects of subsidence and mine induced seismicity <br />further away from the dam and landslide. This subsidence control plan for <br />the Bruce Park Dams and Bruce Park landslide is only required if the <br />monitoring program under Rule 2.05.6(c) shows material damage or <br />diminution of use. <br />Experience at the Bowie No. 1 Mine supports the position that springs and <br />ponds will not be damaged by the effects of subsidence. Under similar <br />geologic conditions, the Bowie No. 1 Mine mined under numerous springs <br />• and ponds with no reported detrimental effect on any of the resources. <br />During the period from 1980 through 1997, as presented on the following <br />table, a total of 12 springs and 28 ponds were undermined. Six springs and <br />six ponds were undermined at depths of less than 800 feet of overburden. <br />Yet there was no detrimental effect on any of the springs or ponds. <br />Bowie No. 1 Mine Hydrologic Monitoring Summary <br /> Overburden No. Overburden <br /> Springs Range Ponds Range <br />Total Analyzed 12 250 ft to 1950 ft 28 100 ft - 2200 ft <br />Less than 800' Overburden 6 250 ft to 750 ft 6 100 ft - 750 ft <br />Advance Only <br />----------------------- 3 <br />----- 400 ft to 700 ft <br />------------ 3 <br />---- 350 ft - 700 ft <br />---------- <br />Secondary Mined 3 250 ft to 750 ft 3 100 ft - 750 ft <br />Greater than 800' Overburden <br />----------------------- 6 <br />----- 900 ft to 1950 ft <br />------------ 22 <br />---- 850 ft - 2200 ft <br />---------- <br />Advance Only 5 1400 ft to 1950 ft 12 900 ft - 2200 ft <br />Secondary Mined 1 900 ft 10 850 ft - 1600 ft <br />• <br />PR-11 <br />2.05 - 114 - 11 /08 <br />~~PRoV£~ <br />