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III IIIIIIIIIIIIIIII <br />~/~`~/~• Cripple Creek & Victor Gold Mining Company 999 <br />1\ l\ A Joint Venture - Pikas Peak Mining Company, Manager <br />~~'t/~/ Operations Offlce Englewood Offlce <br />,(Ll~YST- P.O. Box 191, 2755 State Highway 67 5251 DTC Parkway, Suite 700, Englewood <br />Victor, Colorado 80860 Colorado 80111 <br />(719) 689-2977 • FAX (719) 689-3254 (303) 889-0700 • FAX (303) 889-0707 <br />March 29, 1994 <br />SENT BY FACS1~41LE AND REGULAR MAIL <br />Mr. Berhan Keffelew <br />Environmental Protection Specialist <br />Colorado Department of Natural Resources <br />Division of Minerals and Geology <br />Office of Mined land Reclamation <br />1313 Sherman Street, Room 215 <br />Denver, Colorado 80203 <br />RECEIVED <br />APR n 3 1995 <br />pivision of rvuneral5 is UBOlogy <br />Reference: Request to Use Another Pond as Source of Water for On-Permit Area Haul Road <br />Dust Control -Response To Your Question. <br />Dear Mr. Keffelew: <br />In reference to our request of March 28, 1995 and your telephone message of today, let me add <br />the following information: <br />The DeGussa test work was done on one Pond 4C sample which had a concentration of <br />about 28 mg/I WAD cyanide. DeGussa runs a test sequence which, having applied it to <br />numerous cases, results in very accurate projections of the application rate and the <br />reaction times. In this case DeGussa identitied a reaction time of l6 hours and achieved <br />WAD CN concentrations of 0. I I with applications of 2.5 grid 3.761bs/1000 gal 1ydrogen <br />peroxide and concentrations of 0.46 and 0.23 mg/I WAD CN with applications of 1.52 <br />and 1.88 Ibs/1000 gal. DeGussa therefore recommended an application rate of 2.5 <br />Ibs/1000 gal (0.3 gms/1000 I). Cripple Creek ~ Victor Gold 1.4ining Company then <br />applied hydrogen peroxide at the 2.5 lbs/1000 gal rate to another sample in December <br />1994 and obtained the 0.068 Ing/1 WAD CN result reported to you yesterday. <br />A March 1995 sample of Pond 4C demonstrated a much lower concentration of cyanide <br />in contrast to the 1994 sample assessed by DeGussa - 10.5 v. 28 111g/l. Therefore the <br />application rate of 2.5 Ibs/1000 gal will be conservative in terms of assuring a low <br />concentration of WAD CN. <br />If you require additional information, please let me know. <br />Si~t~erely <br />John E. Hat'daway <br />anager Environmental Affairs <br />FfLF.. CC.4 V31'IP.IX4 <br />