Corps Makes Plant Improvements to Prevent Release of Oil into Tailrace Like most hydroelectric plants designed in the 1960s, the U.S. Army Corps of Engineers' 160-MW Truman Power Plant, near Warsaw, Mo., was built with a station drainage sump that collects all drainage from the plant. As designed, float switches activate sump pumps that discharge liquids directly into the tailrace. Because the system cannot distinguish between types of liquids, in the event of an oil leak in the hydroelectric plant, oil in the sump could be released into the tailrace. This situation was not environmentally sound and needed to be corrected.

The sump system was identified as a problem area in a December 1991 assessment of the plant by a district team that conducted record searches, interviews, and site surveys to determine any areas of environmental non-compliance.

Corps Installed Oil Skimmer

To eliminate the potential problem posed by the Truman Power Plant's sump system, the Corps took the initiative to make several improvements. For containment in the event of a spill, the district installed a Model 6V oil skimmer for the sump, similar to one used at the Corps' Clarence Cannon Dam, also in Missouri. The district also plugged a number of floor drains, and installed speed bumps, similar to those used in parking lots to slow traffic, for spill containment. Additionally, a cart-mounted skimmer is available to serve as a mobile spill control unit for spills elsewhere in the plant. Long-term plans call for oil detectors that will automatically turn off the sump's pumps and turn on the skimmer.

The oil skimmer, which features a floating tube-type collection system, recovers any oil that may have entered the sump through the plant's drainage system. A polyurethane tube floating on the sump surface attracts oil. A motor-driven pulley pulls the tube past two scrapers that remove the oil, and the clean tube then is returned to the sump. The oil drains into a storage barrel and is later placed into a waste oil sump for proper disposal. The skimmer can collect 20 to 30 gallons of oil an hour.

The district team suggested that most of the plant's floor drains be plugged to prevent hazardous substances such as oil, battery acid, and cleaning solvents from reaching the drainage sump. With unplugged drains the substances would freely mix with the sump liquid. All of that liquid would then be considered a hazardous waste, which would increase the amount of hazardous waste to be disposed of.

The plugs are removable; if a spill involving water or another non-hazardous substance occurs, plant personnel can remove the plug and allow the fluid to drain into the sump.
Containment of spills becomes especially important after floor drains are plugged. With that in mind, the Corps purchased rubber automotive speed bumps for spill containment within the Truman plant. The speed bumps are placed in, or in front of, doorways to keep liquids from spreading. The speed bumps--about 4 inches high--permit equipment to be moved about the plant and present a minimum tripping hazard for plant personnel. The Kansas City District learned about the speed bumps from another Corps district, which also uses them for containing spills.

The district is planning to place a permanent oil boom in the tailrace, and presently is designing anchors to secure the boom. Once installed, the boom will minimize the chance of a spill reaching navigable waters and will decrease the cleanup area.

As a result of the modifications at the Truman Power Plant, personnel are now better able to respond to an oil spill than in the past.

Top of Page

Return to Case History Listings Page