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Scullion were 2 pg /L. It is anticipated that mining of the proposed lease would require <br />dewatering with discharge to a sedimentation pond tributary to the ephemeral Red Wash <br />drainage. No measurable levels of selenium were detected in ground water samples from an on- <br />lease test well. <br />Solid and liquid wastes from the Bonanza power plant are treated in a treatment facility that is <br />more than 10 miles from the White River in Utah. There has been no discharge of water from the <br />power plant since 1987. Selenium is not considered to be an issue in the combustion of coal. <br />Based on the values above, there is no evidence to suggest that current mine operations, mining <br />extension into the proposed lease tract, or power plant operation is contributing or would <br />contribute measurably to selenium concentrations in the White River. <br />The Environmental Protection Agency has required special design measures to reduce air <br />emissions at the Bonanza power plant to reduce air -borne pollutants, including mercury. Mercury <br />released from coal combustion at the power plant was measured at 2.11 pounds in 2011, a rate <br />(pounds Hg per gigawatt -hour) considered minimal for coal -fired generators and compliant with <br />Clean Air Act standards. Although Colorado pike- minnow with elevated mercury concentrations <br />(2 µg /g muscle plug, wet weight) were found in the White River in 2008, the source of exposure <br />is unclear. Monitoring of mercury levels in the White River has remained at or below 0.1 µg/l_ <br />since 1979. Measured mercury levels have been in a declining trend since 1993 (power plant <br />began operation in 1985) and have remained essentially zero since 2008. Similar to the <br />discussion regarding selenium, there appears to be no evidence suggesting that past or current <br />power plant operation, using coal from the proposed lease area, is contributing measurably to <br />mercury contamination in the White River. <br />In summary, development of the proposed coal lease acreage and continued fueling of the power <br />plant with this coal may affect, but is unlikely to adversely affect the endangered Colorado River <br />fishes or adversely influence critical habitat. Based on water quality monitoring data, there are no <br />indications that past, current, or proposed mining operations or ongoing power plant operations <br />have contributed to elevated mercury or selenium levels in the White River. Conversely, since <br />mining and power plant operations began mercury and selenium levels appear to have remained <br />static or declined. <br />The WRFO is aware of no further resource issues involved with the Proposed Action that could <br />reasonably influence downstream fisheries. The development and reclamation of widely <br />dispersed sub -acre surface facilities that are invariably sited on level terrain would progress at a <br />rate commensurate with their development over the past 30 years. The addition of sediments <br />originating from these diminutive sites would be indiscernible relative to background levels in <br />the Red Wash watershed, and the potential for long term accumulations of sites susceptible to <br />erosion is improbable given that site reclamation with perennial grasses reduces site <br />susceptibility to soil loss (i.e., on sites formerly influenced by invasive annuals). <br />White - Tailed Prairie Dogs <br />The Proposed Action would not be expected to have any substantive influence on prairie dogs or <br />their habitat. Based on raw probability, it is unlikely that more than 2 -3 acres of habitat would be <br />DOI- BLM -CO- 110- 2012- 0023 -EA 48 <br />