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LJ <br />' 3.0 HYDROLOGY AND MINE DEVELOPMENT <br />This monitoring period from October 1, 1996 to September 30, 1997 has provided the hydrologic <br />' information necessary to assess the adequacy of monitoring program, the adequacy of the <br />mitigative measures designed to protect the hydrology, and identify and quantify impacts that may <br />' have occurred during this period. <br />3.1 Mlning Related Hydrologic Impacts <br />' The only impacts identified to date include: <br />' • withdrawal of water for the mine from the lagoon adjacent to the White River thus <br />reducing the flow in the White River. WFU has legal right to this water. <br />' • Discharge of storm water from ponds RP2/3 and RP4 into Red Wash, a White <br />River tributary. <br />' • Decline in piezometric level in upper sandstone facies at 2-12U as the result of <br />' subsidence above longwall panel #1. This hole has been mined out. <br />• Decline in piezometric levels in monitor holes at the 2-7, 35-4 and 36-2 locations <br />' due to very nearby mining, although an increase in the water level at 35-4 and 36- <br />2 was noted this monitoring period. <br />' • Decline in piezometric level in "lower sandstone facies" as the result of leaking <br />exploration holes (drilled in 1978) that were intercepted by mining, and possible <br />' effects of longwall mining. <br />• Subsidence in Red Wash resulting in ponding of surface water. The ponds quickly <br />' fill with clay and silt with Red Wash maintaining its original channel. <br />' 3.2 Comparison of Projected Impacts Wlth Observed Impacts <br /> <br /> <br />1 <br />1 <br /> <br />The comparisons of the projected impacts (probable hydrologic consequences) with the observed <br />impacts are discussed in the following. <br />The water withdrawal rate from the lagoon in the White River Alluvium this reporting year (October <br />1, 1996 to September 30, 1997) was estimated at 109,075,285 gallons or 334.7 acre-feet) <br />acre-feet. This compares with an expected withdrawal rate of 598 acre-feet per year at full <br />production. Clean coal production during this reporting period was 860,502 tons in addition to <br />420,515 tons of bypassed (not cleaned but shipped) tons compared to projected full production <br />of 1.6 million tons per year. <br />18 <br />