HYDRO25121 - Laserfiche WebLink

Home Browse Search

TEL No. Jun .20.88 644 P.02 ~ ~ III Illlllllllllllll 999 STATE OF COLORADO DIVl510N OF MINLRALS AND GEOLOGY 13x1 trulnlCnl u( NJ W ral RnsuurrCx 131 i 5hrq,l,in SL. Ruam 21 5 Ui~n~ Cr. Colas aAn 0020.3 Phonr. (4U 4) OLL-J S W f AX: UOb 617-P I b4 DATE: May 30, 1995 N'1' CI TO: Berhan Keffelew (`\\ R~NRa~~~~~:~ /'~- ` ~~~ ynnn S LorhhceJ FROM: Jim Pendleton ~' i,~....!]~- F,.r„li~~lra.r,^ Mkharl 6. LLmE Divi>iw~ L3vcal.n RE: Suggested me nt to CRESSON Stipulations ( ermit No. M-80-244) 9. If free or WAD cyanide is detected in the effluent from the Arequa Gulch underdrain in concentrations that exceed concurrent applicable water quality standards for Arequa Gulch, or in any of the monitoring wells surrounding the heap leach, the Office will conclude that heap leach containment has been lost. If free or wAD cyanide-contaminated effluent .enters the leak detection system trenches and sumps at a rate exceeding one (1) gpd per acre, the Office will conclude that heap leach containment has been lost. The operator shall notify the Office within 24 hours in the event of any of these occurrences. Further, the operator shall irnmediately cease application of leaching solution to the heap leach and initiate detoxification within one week. Detoxification shall continue until an acceptable remedy has been approved by the OMLR and irnplemented by the permittee. All fluid volumes collected from the leak detection sumps shall be inventoried by sump weekly and reported to the OMLR in writing once a month. All contaminated fluids (those fluids containing free or WAD Cyanide exceeding applicable water quality standards for Arequa Gulch) from the Arequa Gulch underdrain shall be collected, stored (not to exceed 60 days), detoxified and released. Under no circumstance shall any of this contaminated effluent be Introduced into the heap leach. The permittee shall develop a plan for the collection, storage, detoxification and disposal of all fluids collected from the Arequa Gulch underdrain. No leaching solution shall be applied to the heap leach facility until this plan has been approved by the Office.