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2.05.6(6) <br />No limited extraction zones are proposed for any of the ponds except Pond <br />P-1 because they all lie in zones of minor subsidence impact. <br />A limited extraction zone was established along the bleeder entries in the <br />vicinity of Freeman Gulch and the vent shaft in Freeman Gulch. This limited <br />extraction zone was established to assure subsidence does affect the <br />stability of adjacent old landslides to the extent their deformations were <br />renewed. <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 seismicity and potential translated effects. Deadlines for the <br />study and reports are presented in Stipulation No. 9. <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 />• <br />TR-031 <br />2.05 - 108 - 02/04 <br />/~ P~R6 VED <br />S ~ ~ ~~d 4 <br />