The Department of Energy’s Office of Legacy Management has scheduled repairs to the embankment of Chartiers Creek, near the disposal site in Canonsburg that processed uranium and other ores between 1911 and 1957.
Recent high flows in Chartiers Creek have caused a portion of the creek embankment to erode. About 1,200 lineal feet of the embankment needs repaired to prevent erosion from continuing and destabilizing the embankment.
“Our job is to make sure that creek doesn’t move. We’re trying to keep it contained,” said Ken Broberg, site lead for Navarro Research and Engineers Inc., a contractor for the Office of Legacy Management.
According to Broberg, the project will include replacing filter fabric, importing and placing riprap (rock) on the slope of the embankment, and adding vegetation to any areas that are disturbed.
The Canonsburg disposal site, off Strabane Avenue, houses a containment cell that holds about 226,000 dry tons of contaminated material, including uranium mill tailings, both from the site and off-site locations.
The disposal cell, which cost approximately $48 million, is designed to last between 200 and 1,000 years.
Ores processed at the site included vanadium (used to strengthen steel for use in the auto and railroad industries), radium and uranium.
In 1929, Vitro Chemical Co. acquired the site and produced uranium for the glass and ceramic industries. During World War II, the government enlisted the company to supply uranium for the Manhattan Project.
From 1942 until 1957, Vitro Corp. had a contract with the federal government to recover uranium from ore and scrap.
Milling operations at the site generated radioactive mill tailings, and some were shipped to Burrell Township to be used as additional fill in a railroad landfill.
The Office of Legacy Management anticipates the repairs will help stabilize the embankment. But, noted Broberg, the site lies within a flood plain, so further erosion is possible depending on flows through Chartiers Creek.
A buried riprap wall, approximately 850 feet long and 18 inches wide, is anchored into bedrock and provides an additional barrier.
“We recognize the creek is going to flood, that the creek is going to move over the years. The designers took all of that into consideration when they built the (containment) cell,” said Broberg.
The disposal site is inspected annually by the Office of Legacy Management, which also mows the grass twice annually. An herbicide company makes several trips throughout the year to control unwanted plants.
Legacy Management conducted several erosion control projects over the years, Broberg said. In 2005 and 2008, riprap was shored up on the embankment, and in 2017 repairs were made to areas where riprap was slipping.
The property is enclosed with a fence, and is posted with radiation warning signs.
Work is scheduled to start at the end of July and be completed in mid-June.