Laserfiche WebLink
PERMIT #: M-1977-300 <br />INSPECTOR'S INITIALS: MAC <br />INSPECTION DATE: June 3, 2015 <br />OBSERVATIONS <br />The inspection was conducted by Michael Cunningham and Wally Erickson of the Division of Reclamation, <br />Mining and Safety (Division). The Operator was represented by Ken Mushinski. The primary purpose of the <br />inspection was related to Technical Revision No. 22 (TR22). <br />The Operator submitted TR22 to allow for the installation of a grout curtain in the Sump 10 area, which is <br />located on the south side of Ralston creek and immediately to the southeast of the water treatment plant <br />(WTP). The Sump 10 area has been collecting water mine water at a rate of approximately 30-40 gallons per <br />minute. The majority of the water in Sump 10 is coming from core holes which were drilled in 2012, but which <br />were never grouted. Currently the water is captured and treated before it is discharged into Ralston Creek. <br />The water from the mine contains manganese and sulfates, both of which lead to a decrease in efficiency of <br />the ion exchange treatment system. <br />The Division approved TR22 on April 27, 2015 which allows the Operator to install a grout curtain in this area <br />in an effort to reduce the infiltration of mine water into the sump. The initial grouting pass will consist of 19 <br />holes to be drilled on 10 foot centers to a depth of approximately 35 feet. After the initial 19 holes have been <br />grouted, the Operator will perform packer tests to determine the effectiveness of Phase 1 of the project. <br />Phase 2 will consist of drilling up to 19 additional holes if the results of Phase 1 indicate mine water is still <br />seeping into the sump. In addition, the existing core holes drilled in 2012 will be grouted. The entire project is <br />expected to take approximately 3 weeks to complete and a copy of the grouting as -built report will be <br />provided to the Division within 30 days of completion of the project. During the inspection the Division <br />observed the drill rigs setting up in preparation of drilling for Phase 1. <br />The timing of the project is related to floods of 2013, which washed out the access road and forced the <br />Operator to evacuate the site. The mine access road is owned by Jefferson County and is maintained by the <br />Operator. The Operator worked with Jefferson County and Denver Water to formulate a plan for <br />reconstructing the access road. Reconstruction of the road has included clearing substantial amounts of <br />debris, reinstalling culverts and raising the overall grade of the road. The exceptionally wet spring has delayed <br />efforts to complete the project. Currently the road is traversable; however, the Operator still has to raise the <br />grade of several sections and has to complete grouting at a couple of the installed culverts. It is anticipated <br />that the road work will be complete within a month. <br />Prior to reconstruction of the access road, the Operator was able to access the site through an alternate route <br />that crossed through Jefferson County Open Space. However, the Operator was unable to transport the <br />chemical reagents used in the reverse osmosis WTP and therefore this component of water treatment at the <br />mine has been suspended since the flood occurred. The reverse osmosis WTP will be brought back on-line <br />once the grouting project is complete. The Operator informed the Division that the waste resin from the ion <br />exchange system will be sent to an out of state facility for disposal; the disposal of the waste resin is regulated <br />through the CDPHE Radioactive Materials License (RML -369-03). <br />Page 2 of 5 <br />