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LJ <br />2.05.6(6) <br />Portions of Hubbard Creek and Hubbard Creek road are located in a zone <br />of greatest subsidence impact. For this reason, these areas will be protected <br />by a limited extraction zone. The limited extraction zone is defined by <br />extending a safety zone a distance of one hundred feet from the creek then <br />projecting a line down at the 25° angle of draw to the coal seam. <br />A detailed subsidence study for Terror Creek Reservoir dam will be <br />completed prior to mining within one mile of the dam which will occur late <br />2002 or early 2003. The study will establish baseline conditions, potential <br />mining-induced seismicityand potential translated effects. Deadlines for the <br />study and reports are presented in Stipulation No. 9. <br /> <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 Overburden <br />- ---" "'---- _ No. S rin s Ran a No. Ponds Ran e <br />Total Analyzed i 12 250 ft to 1950 ft 28 100 ft - 2200 ft <br />Less than 800' Overburden i 8 250 ft to 750 n 8 100 ft - 750 it <br />_____________________________l__________ <br />I ________________ _________ ____________-_ <br />Advance Only I 3 400 ft to 700 ft 3 350 ft - 700 ft <br /> <br />Secondary Mined i 3 250 ft to 750 ft 3 100 ft - 750 ft <br />Greater than 800' Overburden I 6 900 ft to 1950 ft 22 850 ft - 2200 ft <br />_____________________________l__________ <br />i ________________ _________ ______________ <br />Advance Only I 5 1400 ft to 1950 ft 12 900 ft - 2200 ft <br />-___-_-_ <br />Seconda Mined I 1 900 ft 10 850 ft - 1600 ft <br /> <br />This data provides significant validity to the Operators position that no <br />subsidence protection will be provided for springs or ponds unless they are <br />a decreed water right and only then if the spring or pond has an overburden <br />depth of less than 800 feet. <br />PR-08 <br />19PP,2ov6D <br />9~zs/o3 <br />2.05 - 109 - 07/03 <br />