Within the next several weeks, a four-acre site in Visalia, California, that had been brimming with creosote and other chemicals is expected to be formally removed from the Environmental Protection Agency’s Superfund national priorities list, the rogues’ gallery of the nation’s most polluted sites. For 80 years Southern California Edison, the site’s owner, had used its facility there to treat utility poles. Back in 1997, SCE had already been remediating the subsurface for 20 years with conventional processing, and it was looking at another 30-60 years to finish the job.
Then along came a technology invented by two geophysicists at Lawrence Livermore National Laboratory (LLNL) to clean up a decades-old gasoline spill on the lab grounds. Known as dynamic underground stripping, the new process dramatically accelerated the pace of contaminant removal from 10 pounds a week using conventional means to an astounding 46 000 pounds per week. The key...
