OCR

be placed to an exact grade, it was important that the thickness did not go below four inches, in order to preserve the waterproof qualities of the floor. Joints in the two courses were overlapped by three feet, to ensure a perfectly watertight seam. The hugh paving operation was spread over two seasons. Fall comes early to the exposed Ozark mountains , and during the winter of 1962-1963 the site was virtually abandoned to the wild turkeys, deer, and hibernating rattlesnakes which were the only signs of life on the desolate mountain. In May 1963 paving began again and was finished in a few weeks. With the power station and lower reservoir situated on the Black River completed, ail that remained was to fill the gigantic reservoir and make necessary leakage repairs. There was some leakage in various places as might be expected when, first putting a large structure of this type in operation. When drained for inspection, some ruptures were discovered in the floor. These were located where rapid emptying had caused hydraulic back pressure. Also, some were located where there had been entrapped air in the subbase. Other leaks were discovered in the copper expansion joints in the concrete facing. Ruptures in the floor were repaired by spraying with RC-4 Asphalt and rolling after applying a layer of fine traprock. Choice of Asphalt Upheld Of the choice of asphalt for the floor lining, R. N. Weldy, Chief Engineer of the project, said "It has done everything we expected of it. We were fortunate in selecting the asphalt because it has been excellent as construction platform. Cars, trucks, and heavy equipment have traveled over it with making repairs. Other types of floor seals which we considered would not nave held up under this traffic." The formal opening of the new power station was held in October 1963, with local, state, and national dignitaries present. As the generators pulsed into life to send current swiftly toward distant St. Louis, witnesses of the official opening far outnumbered the workers who will staff the new complex. Only a shift of maintenance men will be required to attend the plant, while the generating and pumping operations will be controlled by pushbutton from Union Electric's Osage Plant at the Lake of the Ozarks and the load dispatcher's office in St. Louis. The power company officials estimate the money saved by curtailing the expansion of expensive steam power plants, plus the more efficient equipment which will be available when it does become necessary to expand the steam plants, will make Taum Sauk a bargain at 50 million dollars.