LIVERMORE, Calif. - Lawrence Livermore National Laboratory's technology was instrumental in cleaning up Southern California Edison's Visalia Pole Yard, which is scheduled to be taken off the Environmental Protection Agency's Superfund list this week.
LLNL, a National Nuclear Security Administration laboratory, used dynamic underground stripping (DUS), a Lab-developed steam-cleaning technology that not only cleaned the site more than 100 years sooner than originally estimated, but also saved millions of dollars.
Southern California Edison had used the Visalia site for 80 years to treat utility poles by dipping them into creosote or pentachlorophenol, which by the 1970s, had seeped into the subsurface soil and groundwater to depths of approximately 100 feet (30 meters). The Visalia pole yard bore the distinction of being one of the original Superfund sites. Twenty years later, Southern California Edison was looking for a faster and more efficient way to treat the soil and groundwater.
And that's where Livermore geophysicists Robin Newmark and Roger Aines entered the scene. The duo, along with LLNL and UC Berkeley colleagues, had developed DUS, which was first successfully used in the cleanup of an underground gasoline spill at Livermore Lab in 1993.
They found that contaminants were removed 50 times faster than with the pump-and-treat process. The cleanup at the Livermore site, estimated to take 30 to 60 years with pump-and-treat, was completed in about one year. In 1996, regulators declared that no further remedial action was required. It served as a proof of concept to use the same method at other contaminated sites.
"It cleaned it up in no time," Aines said. "We thought the same method could be used at other sites."
Later, Livermore scientists developed hydrous pyrolysis/oxidation (HPO), a process that
converts contaminants in the ground to benign products such as carbon dioxide, chloride
|Contact: Anne Stark|
DOE/Lawrence Livermore National Laboratory