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in direct hydraulic communication with Ralston Creek, AR:00083, and the alluvial fill material <br />has affected the water quality of Ralston Creek, AR:00203; 00043. Before the Hearing, Cotter <br />had scheduled partial source removal of the alluvium and fill for 2010. AR:00043; 00236. <br />For 26 years, Cotter has studied alluvial groundwater at the Mine, in detail, by <br />monitoring at twelve monitoring wells and one domestic well, including the collection of water <br />level and water quality data. AR:00056; 00205. The Division had determined the groundwater <br />point of compliance to be Ralston Creek at the lower property boundary, called SW-BPL <br />(Surface Water - Below Property Line). AR:00354; 00052. The new uranium standard for <br />groundwater is 0.03 mg/L. Alluvial groundwater flows to the southeast, the same direction as <br />Ralston Creek flows. AR:00932:12-14; 00502. Because all of the groundwater flow surfaces <br />and flows to Ralston Creek just upstream from SW-BPL, Cotter's groundwater compliance is <br />measured at SW-BPL. AR:00932:24-00933:6. <br />The Schwartz Trend is a natural geologic feature with uranium deposits and it intersects <br />Ralston Creek about 1,900 feet southeast of the Mine. AR:00078; Order ¶ 27, 00849. Based on <br />water quality monitoring and a gamma survey in and along Ralston Creek, the mine pool does <br />not contribute uranium to Ralston Creek via the Schwartz Trend. AR:00087; 00263; 00947:13- <br />25; 00950:16-00951:20; 00522. <br />The water quality in Ralston Creek fluctuates according to the season. AR:00261. <br />Lower concentrations of uranium appear in the spring when spring runoff results in dilution, and <br />higher concentrations appear in the fall when the creek is drier. AR:00931:8-00932:4. An <br />example is the concentration of uranium in Ralston Creek in April 2010, which essentially met <br />the stream standard for uranium of 0.03 mg/L. AR:00261; 00275-83; 00501. The May 2010 <br />8