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Gold King Mines Corporation P.O. Box 299 Silverton, Colorado 81433 Telephone (970)387-5813 Fax (970)387-5760 ~~ oF~,~' ]~'~~® ~P 'a ~s~ November 17, 2003 Mr. Wallace Erickson, Reclamation Specialist Department of Natural Resources Division of Minerals and Geology Durango Field Office 701 Camino Del Rio, Room 125 Durango, CO 81301 RE: Koehler Tunnel Bulkhead Construction Certification Report Dear Mr. Erickson: Ate, ?~'~' .;. ~' x4d9 pry ale ~~de~ ~'~"°'"'~~~~%~~~~,~ ., $~ntiystc~e Nt~ne ~~ M -1977- 378 '' ygCVS~f S! ~' nsenfi ~ecre~ This letter report is to provide certification that construction of the Koehler Tunnel bulkhead meets or exceeds design criteria. Submittal of a construction certification report was committed to by Gold King in their contract for construction of the bulkhead with Sunnyside Gold Corporation. Pre-pour inspections were conducted by DMG and the design engineer, John F. Abel, Jr. P.E. on September 5, 2003 (letter report attached). No deficiencies were found in either pre-pour inspection. Bulkhead location The approximate center of the bulkhead, approximately six feet above the sill, on the air- side face (side towards surface) of the bulkhead is located at station 3+02 measured from the rock face at the portal at an approximate elevation of 11,200 feet. Samples of rock from both ribs and the back were taken and sent to testing laboratories to verify adequate rock strength for the bulkhead location. Cores were taken from the three samples tested to failure. The test results are attached and considered satisfactory. One core exhibited a low value failure. This failure was due to a combined shear/fracture failure and does not represent the strength of the rock in place. The construction stages for certification are listed below.