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<br />• <br />\J <br />JOHN F. ABEL, JR. <br />MINING ENGINEER <br />Mr. Larry Perino <br />Sunnyside Gold Corp. <br />P.O. Box 177 <br />Silverton, CO 81933 <br />Dear Larry: <br />370 LOOKOUT VIEW COURT <br />GOLDEN, CO 80407 <br />303279-4907 <br />FAX 278$163 <br />JFAbeI]®aCM.com <br />November 15, 2002 <br />This is the letter report you requested concerning my <br />inspection on November 12, 2002 of the completed preparations for <br />filling the third American Tunnel Bulkhead at approximately Station <br />3+75. The constructed (as built) bulkhead forms and rebar <br />installed equal or exceed the bulkhead design detailed in my <br />January 15, 2001 letter report. The 13-ft height of the American <br />Tunnel at the bulkhead location is less than the 15-ft design <br />height, apparently the result of decreased overbreak and ballast <br />thickness in the floor. The nominal 12-ft design width of the <br />tunnel is greater than the actual measured maximum 11-ft 9-in <br />tunnel width within the bulkhead forms. The measured 11-ft 2-in <br />bulkhead thickness exceeds the 11-ft design thickness. The as <br />built center to center spacing of the #10 rebar in the downstream <br />cage is 6-in, which is closer than the specified 7-in spacing. <br />Therefore, 2.590 square inches of tensile reinforcement was <br />provided per foot of tunnel width when only 2.177 square inches was <br />specified. All of these differences increase the allowable load <br />carrying capacity of the bulkhead by 39.2 more than the bulkhead <br />design. The rebar cages are 3.5-in from the bulkhead faces is as <br />specified in the design report. <br />I arrived at the bulkhead location at 7:00 a.m. and entered <br />the bulkhead for the inspection at approximately 7:30 a.m. Most of <br />the #10 bars had been tied into the downstream cage at the minimum <br />3.5 inches from the face of the downstream bulkhead form. Only the <br />final three horizontal bars had not been tied into the downstream <br />cage in order for final access for cleaning and initial filling of <br />the form. The horizontal bars were hanging above the access and <br />inspection opening, ready for installation when the concrete pour <br />reaches that elevation. The three vertical bars that had. been <br />spread sideways for access to the form were tied into the cage near <br />the floor. They will be pulled back and tied into the cage ~as the <br />concrete rises in the form. The downstream #10 tension bars were <br />measured on 6-inch centers and the minimum 3.5-in spacing of the <br />rebar cage from the bulkhead forms, as specified. The #6 shrinkage <br />