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overlying Brushy Basin shale of the Morrison Formation, more frequent sampling of <br />background groundwater quality is not recommended. <br />Final permit limits will be developed once 8 -10 samples have been collected from the <br />monitoring well network. Intrawell statistical methods will be applied and /or other <br />best practices consistent with EPA guidance (EPA 2009). Final permit limits applicable <br />at the compliance wells will be developed on an intrawell basis, based on these <br />statistical evaluations. This statistical analysis will be conducted by Denison in <br />consultation with DRMS, and will be provided to DRMS in a report for review and <br />approval. Although permit limits will not be applicable to the upgradient and <br />intermediate wells, statistical analysis based on 8 to 10 quarterly samples will also be <br />performed on those wells, on an intrawell basis, to determine baseline conditions. <br />These statistical analyses will also be presented in the final report. <br />Assessment of Potential Mining Impacts Using Upgradient and Intermediate Wells <br />As discussed in Section 8, the ambient water quality in close proximity to the <br />underground workings shows elevated levels of uranium, vanadium and other <br />elements that are naturally associated with the uranium and vanadium <br />concentrations. This is likely attributable to a combination of natural and <br />anthropogenic factors. The Statement of Basis for the BSGW addresses this issue as <br />follows: <br />The Commission intends to allow for flexibility in locating the point or points <br />of compliance within the specified area. After the point or points of compliance <br />are determined, applicable ground water quality standards are to be met at <br />these locations. Mining activities are recognized to occur within ground water <br />bodies and that water quality within the disturbed area will obviously change. <br />The point(s) of compliance established outside the area anticipated to be <br />disturbed may protect the water body while allowing the mining activity. <br />Accordingly, the permit limits will not apply to monitoring wells located within the <br />mine permit boundary. The upgradient and intermediate monitoring wells will be <br />used to better understand spatial variability in groundwater quality, to understand <br />the effect of the Sunday Mines Complex on groundwater quality over the life of the <br />mine, and to facilitate evaluation of any additional environmental management <br />activities that may be necessary to protect groundwater resources in the future. <br />The intermediate wells will be located within areas planned to be mined in the future, <br />which will require that the wells be abandoned prior to cessation of mining. Data <br />collected from the intermediate monitoring wells will be assessed and summarized in <br />the annual groundwater monitoring report. Similarly, results from the Topaz <br />monitoring well stipulated by BLM will be assessed and summarized in the annual <br />groundwater monitoring report <br />C \ Users \cwoodward1Desktop \Sundays1FINAL - Environmental Protection Plan Sunday Mines Revised January 2012 docx <br />11 -9 <br />