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June 25, 2010 8 of 15 <br />"pump column" (a.k.a. "drop pipe") which is 3-inch diameter steel discharge pipe which threads into the <br />top of the pump. Each 10-ft segment of discharge pipe would weigh 79 pounds with couplings, for a total <br />weight of 3,950 pounds for all 50 pipe segments. A 600-ft reel of 0-gage insulated copper pump wire <br />would weigh 930 pounds. This equipment would have to be carried down the 45-degree slope of the <br />Sunshine raise. A pneumatic crane-like pulley system would have to be designed to hold the weight of the <br />pump column (pump, motor, discharge pipe, and electrical wire) as the pump was lowered into the shaft. It <br />is not clear that 10-ft of clearance exists in the old hoist room at the top of the shaft on the Steve Level. If <br />not, 5-ft joints of 3-inch drop pipe could be special ordered. In that case, 100 segments of pipe would need <br />to be connected as the pump was lowered into the shaft and the total weight would be greater (4,100 <br />pounds) due to additional couplings. Each joint or coupling represents a possible failure point. And <br />although the rock in the Schwartzwalder Mine is competent hard rock, there is no guarantee that the shaft <br />has remained (or will remain) open to that depth. <br />The second method would utilize a boom truck to install the pump through a hole drilled vertically into the <br />shaft from the hillside above the mine. The location of the shaft from the hillside would be difficult to <br />determine, and an underground survey would have to be conducted to tie in to the surface features (Figure <br />4). If the correct location could be identified, a drilling contractor would have to drill through 300 feet of <br />rock and open cavities without deviation to hit the 74-square foot target of the #2 Shaft (Figure 5). <br />Drilling through open cavities is often more difficult than drilling through competent rock, because there is <br />no hole to stabilize the bit and avoid deviation, and no means of flushing the hole to bring up cuttings from <br />around the bit. Without "return" of drill cuttings, a driller would be drilling blind into the rock below the <br />existing voids, with a high potential for getting the bit stuck in the hole. Few drillers may be willing to take <br />on this challenge, due to the high probability of damaging their equipment. If the hole could be <br />successfully drilled, steel casing would have to be set in the hole to keep the hole open and meet the <br />requirements of the Colorado well construction rules (2 CCR 402-2). Without a "bottom" of the hole, <br />sealing the annular space (as required by law) would be difficult. If well casing were successfully installed, <br />the pump could be set vertically from the surface, provided that the shaft remained open to a depth of 500 <br />feet below the Steve Level. Finally, a buried pipeline would have to be installed on the steep hillside <br />leading down to the water treatment plant.