Innovative technology - an electrical current melting contaminated earth into an impermeable glass slag - is the solution to the Wasatch Chemical toxic waste mess, the Environmental Protection Agency and state officials have decided.
Wasatch Chemical is an 18-acre site at 1979 S. 700 West, where some of Utah's worst soil pollution occurred.From 1957 to 1969, industrial operations at the site included producing bleach, refilling chlorine cylinders and packaging and distributing of acids, caustics and organic solvents. From 1969 to 1978, pesticides, herbicides, fertilizers, industrial chemicals and cleansers were formulated, blended and packaged. Agricultural chemicals were stored there from 1978 to the present.
Investigators discovered severe soil, surface-water and waste-sludge contamination at the site, according to a March 1990 report. Some groundwater laced with solvents escaped the site.
The Utah Health Department and EPA recently signed a record of decision selecting in-situ vitrification as the remedy process. Contaminated soil will be moved to one location - the "vault" where chemicals were once stored - and electrodes will be placed in. The electrical current will fuse the material into a glass substance.
The in-situ vitrification process at the site is expected to cost nearly $3.4 million.
"Contaminated soil, sludges and waste would be placed on and above the vault on Lot 6," says a work plan. "Destruction of the contaminants would be achieved as a result of the high temperature within the melt," expected to reach from 3,000 to 3,500 degrees Fahrenheit.
Presently, the site is owned by Entrada Industries Inc., a subsidiary of Questar, which is also the owner of Mountain Fuel Supply Co.
"The EPA evaluated it (in-situ vitrification) very carefully and decided it was a viable alternative to removing the contaminants from the site," said Entrada spokesman Curt Burnett. "We've looked at it carefully. Obviously we're not going to get involved with the process unless there is an excellent chance of it working correctly."
Renette Anderson, community relations coordinator for the state's Superfund cleanup programs, said the earth-melting procedure will take place repeatedly on each pile of material. "When it's completed, what we have left is a big chunk of glass," she said.
The contaminated groundwater will be pumped and treated to remove organic solvents. Then it will be discharged to a sewer system or a drainage ditch adjacent to the site.
Within the next three or four months, detailed decisions will be taken on how to proceed. Once the project begins, it may be completed in only a matter of weeks, Anderson said.