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Condition #1: Baseline Water OuaJity Sampling <br />Baseline ambient groundwater conditions of the potentially affected aquifers shall be established <br />through sampling during a minimum of five quarters prior to mining. <br />Aquifers to be sampled shall include, but not necessarily be limited to, the St. Charles River alluvial <br />aquifer and the Dakota aquifer. During and after drilling of the supply well into the Dakota aquifer, logs of <br />those wells shall be examined to determine if water was encountered in the Codell Sandstone. Provided that <br />water is encountered in the Codell Sandstone, that unit shall also be monitored. <br />Groundwater samples shall be collected and analyzed from a minimum of eight separate events over a <br />time span of at least five quarters. DMG recommends sampling on a monthly basis for 24 months prior to the <br />beginning of mining. <br />Except as noted hereafter, all samples collected during the baseline water sampling program shall be <br />analyzed for the parameters listed in Tables 1, 2, 3 and 4 of the Colorado Department of Health and <br />Environment Water Quality Control Commission, Regulation 41, Basic Standards and Methodologies for <br />Groundwater. At the operator's discretion, groundwater samples need not be analyzed for the following: total <br />coliforms, CN (free), chlorophenol, color, corrosivity, foaming agents, and phenol. In addition to parameters <br />listed in the previously named tables, with exceptions, all samples shall be analyzed for ammonia. Samples <br />shall be analyzed by such methods so as to produce results with detection limits lower than the regulated value. <br />Upon adequate completion and submittal of baseline water quality sampling results, the Division shall <br />establish the following: <br />A) A list of indicator parameters to be analyzed from subsequent sampling; <br />B) Numeric protection levels; and <br />C) Sampling frequency, all in accordance with groundwater regulations. <br />All monitoring wells shall be permitted by and constructed in accordance with the Office of the State <br />Engineer. In addition, the location of the wells must be submitted to and approved by the Division prior to <br />construction. <br />l6 <br />