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several feet deeper within the well and pumping resumed on September 28, 2011. <br />• Sump 8: Installed on approximately November 12, 2010. Pumping was initiated <br />November 16, 2010, but pumping was soon terminated due to very low water <br />recharge rates. A special low -flow pump (rated at several gallons per minute) was <br />installed and regular operation of this sump resumed on September 28, 2011. <br />• Sump 9: Sump 9 was installed on November 10, 2010 using a spare pump and 48- <br />inch corrugated steel conduit that was obtained and manually slotted at the mill in <br />Canon City. Pumping was initiated November 17, 2010. Burial of piping/electrical <br />infrastructure for permanent winterization was performed in conjunction with <br />installation of Sumps 5 and 8. Groundwater extraction in this area of the site was <br />originally conceived as simply placing a pump in the existing pond in the area of the <br />formerly lined emergency overflow retention pond. It was later determined, however, <br />that more effective groundwater capture could be realized by placing a simplified <br />sump within an existing trench located upgradient near the concrete retention ponds <br />(this trench had been used as part of construction- related dewatering efforts). <br />• Sump 10: In late June 2011, a 48 -inch corrugated HDPE casing pipe, left over from <br />earlier sump construction activities, was placed during pond backfill efforts at the <br />eastern end of the pond in order to continue monitoring groundwater levels and water <br />quality in this area of the site. After initial analytical water quality results from this <br />location were obtained, a spare pump was installed and spare piping was constructed <br />above ground to temporarily enable pumping from this location to the water treatment <br />plant (pumping was initiated late in the day on July 1, 2011). No French drain will be <br />installed in association with this sump. Sump 10 will be converted into an official, <br />permanently winterized sump in October 2011 and added to the quarterly <br />groundwater monitoring program beginning this quarter. Bonding for this <br />winterization will be posted with DRMS prior to construction. <br />2) Request: A complete map of all sumps and related features that have been installed at the <br />site. The map must accurately depict the locations of all sumps as built, including locations <br />of all associated pumps, piping and power distribution, whether buried or on ground surface. <br />Also include on the map the treatment discharge outfall, the piping between the treatment <br />plant and the outfall site, and the location of all monitoring wells. <br />Response: See Figures 1 through 3. <br />3) Request: The total quantity of uranium removed to date by the water treatment system since <br />June 2010, and the quantity of uranium currently being stored on site. <br />Response: As of September 16, 2011, approximately 1,440 pounds of uranium have been <br />removed from alluvial groundwater and prevented from migrating to Ralston Creek. This <br />represents the total amount of uranium stored on site (as of 9/16/11). <br />4) Request: The current and historical pumping rates from each sump, the current and <br />historical uranium concentrations from each sump, and if available the historical mass of <br />uranium captured by each sump. <br />4 <br />