The report gives results of a survey of the flue gas desulfurization (FGD) system on Unit 6 of Louisville Gas and Electric Co.'s Paddy's Run Power Station. The closed-loop system, which was started up in April 1973, uses a slurry of carbide lime in a marble-bed scrubber. The carbide lime, a waste by-product from a nearby acetylene manufacturing plant, contains 90-92 percent calcium hydroxide, 2-2.5 percent silica, 3-8 percent calcium carbonate, and 0.1 percent magnesium oxide. Sludge is stabilized by mixing thickener overflow with carbide lime before vacuum filtration. The sludge, containing about 40 percent solids, is trucked to a nearby 10-acre borrow pit, used as a landfill area. The Paddy's Run Station is used primarily to meet summer peaking loads. Boiler No. 6 is operated infrequently because of its low thermal efficiency (heat rate is about 13,000 Btu/kWhr). On the basis of the performance at Paddy's Run, Louisville Gas and Electric Co. is pursuing plans to install similar carbide lime FGD systems at other power stations.