Laserfiche WebLink
F. 1 1 <br /> STATE OF COLORADO <br /> DIVISION OF MINERALS AND GEOLOGY <br /> Department of Natural RCSourCC; Post-it'Fax Note 7671 Ova cages► <br /> 1 313 Sherman St, Room 215 <br /> Deriver,Colorado 8020) v -'< '/ i 5t7✓t From l�IGl1 <br /> Phone (303)866-356 �:n/De Ft. , Co. �� <br /> FAY;(30})83: R106 Pnona r Phone DEPARTMENT OF <br /> Fax x , 7�� Z�! 7 s o Fax m NATURAL <br /> EZESOURCES <br /> DATE: UMay 30, 1996 Roy Rome, <br /> COI error <br /> �TO• Wall Erickson James S tocFhesd <br /> FROM: Allen Sorenson � > ^f).•r.r, <br /> RE: Mine Pool Alkaline injection, Sunnyside Gold Corp. , sunnyside <br /> Mine, Technica Revision TR-19, Permit No. 177-378 <br /> Injection of alkaline water into the mine pool to be created upon closing <br /> the valve at the American Tunnel bulkhead is seen as environmentally <br /> advantageous, and is a requirement of the settlement agreement between <br /> sunnyside Gold Corporation and the Water Quality Control Division. In <br /> thinking of possible disadvantages to alkaline injection, I considered the <br /> potential for high pH waters to cause deterioration of the concrete <br /> bulkheads that will impound the mine pool, and determined that this is not <br /> likely to occur. Deterioration of concrete structures can result from <br /> contact with inorganic acids, acetic and carbonic acids, and sulfates of <br /> calcium, sodium, magnesium, potassium, aluminum, and iron. The addition <br /> of high pH waters into the Taine pool will actually reduce the threat of <br /> concrete deterioration to be caused by acids, and the potential for <br /> concrete deterioration to be caused by sulfates was addressed during <br /> installation of the bulkheads by the use of a Type v (sulfate-resisting) <br /> portland cement. Also, the concrete mix used for the bulkheads was <br /> designed to result in a structure with extremely low porosity, which will <br /> provide additional resistance to chemical attack. <br /> Based on my review of the TR-19 application, as well as discussions with <br /> Harry Posey, I would recommend that the technical revision be approved <br /> without conditions. <br /> cc: Harry Posey <br /> Bruce Humphries <br /> C:\WP51\SGCTRI9 <br />