Laserfiche WebLink
Request for Technical Revision 13 <br />Cotter Corporation (Cotter) wishes to install a temporary water treatment plant (50 gpm) at Sump <br />Number One and begin treatment by July 3, 2010. Information relevant to this request is contained in <br />email correspondence between Cotter and WQCD personnel (see Attachment 1). <br />The following is a description provided by Water Treatment Technology, LLC (WRT): <br />WRT Temporary Treatment Plan <br />WRT will provide a temporary treatment system for the removal of uranium only <br />for a period of approximately 4 to 5 weeks. The system will be designed to handle a <br />continuous flow of approximately 50 GPM. <br />The equipment will consist of a pre-filtration skid utilizing bag filters with 100 <br />micron nominal filtration, followed by two treatment vessels operating in series. Each <br />treatment vessel will be approximately 63" diameter x 86" tall and will each contain <br />approximately 85 cubic feet of Z-920 Uranium Removal Media. Based upon an <br />anticipated flow rate of 50 GPM, raw water uranium level of 2,000 ug/L, and a raw water <br />sulfate level of 200 ug/L, this system should deliver treated water that contains less than <br />30 ug/L for the treatment period of about 4 weeks before the treated water uranium levels <br />may begin to increase above the 30 ug/1 level. Z-92 Uranium removal media is NSF <br />Standard 61 certified for the treatment of drinking water. No chemicals are used in this <br />treatment process. Each treatment vessel contains a safety discharge screen on the outlet <br />piping to prevent treatment media from exiting the vessel. This temporary treatment <br />system represents a scaled down version of the long treatment process that is planned for <br />this site. <br />Whetstone Associates has provided to Cotter its Technical Memorandum dated June 18, 2010 (see <br />Attachment 2), which also describes the system. <br />The following is additional information requested by the Colorado Division of Reclamation, Mining & <br />Safety (DRMS): <br />Interim Water Treatment <br />It is Cotter's belief that the most immediate and effective possible interim measure to rapidly reduce <br />uranium loading in Ralston Creek from shallow groundwater percolating through the alluvium and fill <br />is to temporarily install and operate a small portable water treatment system to intercept and treat <br />water reporting to Sump Number One. To meet the July 3, 2010 date, Cotter has procured temporary <br />water treatment equipment (50 gpm) and services from WRT for this purpose. <br />The 100 gpm water treatment system is scheduled to be operational by July 31, 2010. A conceptual <br />design drawing for this system is shown in the diagram below. The interim 50 gpm system will be <br />identical in function to the 100 gpm system, but will not include certain elements or components, such <br />as a surge tank. <br />2