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2.05.6(6) <br />Pond P -1 is located in a zone of greatest subsidence impact. For this <br />reason, this pond will be protected by a limited extraction zone. The limited <br />extraction zone is defined by extending a safety zone a distance of fifty feet <br />around the pond and then projecting a line down at the angle of draw until it <br />intersects the coal seams. <br />Pond P -2 is located in a zone of intermediate subsidence, however the <br />overburden below P -2 is nearly 1,000 feet. For all practicable purposes P -2 <br />is in a zone of minor subsidence. Therefore, no limited extraction zone will <br />be provided for Pond P -2. <br />Ponds P -3 through P -6 are located in a zone of minor subsidence in an area <br />of overburden greater than 1,000 feet. Therefore, no limited extraction zone <br />will be provided for Ponds P -3, P -4, P -5 and P -6. <br />Five additional ponds are located within the permit boundary in zones of <br />minor subsidence. They are Pond 33 -3, Spring /Pond 33 -5, Pond 33 -7, <br />Spring /Pond 34 -2 and Spring /Pond 34 -11. Two ponds are located outside of <br />the permit boundary in zones of minor subsidence. They are Pond 32 -3 and <br />Spring /Pond 33 -6. Refer to Map 9, Hydrologic Location Map for location <br />information. <br />In the mine expansion area to the west there are forty (40) monitored springs <br />with ponds and ponds located within the permit boundary. See table at the <br />end of this section. There are three of the hydrologic features that have <br />overburden less than 800 feet. Pond 8 -4 has and overburden of 350'. Pond <br />17 -1 has an overburden of 450 feet. Spring 21 has an overburden of 475'. <br />Pond 8 -4 and Spring 21 overly the south mains so they by default are <br />located in a limited extraction zone. Pond 17 -1 is near some of the old <br />Bowie No. 1 mine workings that are within the permit boundary. Because of <br />its location, Pond 17 -1 will not be undermined by the Bowie No. 2 mine <br />workings. Therefore, the three hydrologic features that have low overburden <br />will not be affected by subsidence. <br />PR -14 2.05-159- 03/14 <br />