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Potential Effects on Ground Water <br /> Colowyo's operations may affect bedrock ground water of one formation, the Williams Fork <br /> Formation, which contains the ten coal seams to be mined and is the surface outcrop on the <br /> permit area. However, impacts to the Williams Fork are deemed minimal because water <br /> produced from coal zones is of known poor quality (documented in USGS and U.S. <br /> Environmental Protection Administration (EPA)reports) and well yields are low. <br /> There is little development of the ground water resource in the local area. The wells that have <br /> been completed in the Williams Fork interbedded sandstones yield less than five gallons per <br /> minute and their uses are limited to domestic and/or livestock use. Nearby residents haul <br /> drinking water supplies from Craig and Meeker. <br /> The lack of a continuous, regional ground water system on the property within the stratigraphic <br /> section of the Williams Fork Formation was documented in the 1979 report prepared by Leonard <br /> Rice Consulting Water Engineers (Exhibit 7A of the PAP). <br /> In addition, 17 test holes were drilled and their corresponding records collected when the <br /> property was originally explored. All well data confirmed that where water was encountered it <br /> was limited both vertically and laterally and it was encountered under perched conditions (a <br /> discussion of well test data is in Section 2.04.7 of the PAP). <br /> A slight potential for degradation of alluvial ground water was recognized in the 1982 Findings <br /> Document. A plan to monitor alluvial ground water on Good Spring and Wilson Creek was <br /> developed by Colowyo. Results of monitoring in AHRs indicate some detectable impacts on <br /> alluvial ground water to date. A slight increase in TDS at the New Good Spring Well from 1989 <br /> to 2012 is not significant. An increase in TDS in Gossard well from 1983 to 2006 was detected, <br /> but the concentrations have been decreasing in recent years. <br /> Pursuant to Rule 2.07.6(2)(c), the assessment of the probable consequences of the proposed <br /> mining operation and the assessment of the probable cumulative impact of all anticipated mining <br /> in the area on the hydrologic balance, as described in Rule 2.05.6(3), have been made. The <br /> proposed operation has been found to be designed to prevent material damage to the hydrologic <br /> balance outside the permit area. <br /> During the review of PR-02, the Division further evaluated potential impacts to groundwater <br /> within and adjacent to the permit area and with regard to establishing groundwater points of <br /> compliance. Three specific zones of groundwater that have the potential to be impacted were <br /> evaluated. These include bedrock groundwater, backfill and excess spoil groundwater, and <br /> alluvial groundwater. A synopsis of the Division's review is provided below. <br /> Bedrock Groundwater <br /> The Division has determined that coal mining operations at the Mine do not have the potential to <br /> Proposed Decision and Findings of Compliance January 5,2023 <br /> Permit Renewal No. 8 Page 141 <br />