Southern California Cleanup Project Embodies the DTSC Mission
In mid-July 2015, the project team that provided environmental oversight for cleanup of a chemical distribution facility in San Bernardino County notified the community that the “corrective action” associated with the project was complete.
This was a routine announcement for Environmental Scientist Stephanie Lewis and others overseeing the work. It was significant, however, for current and future workers on the 4.3-acre Ashland Inc. property in Colton. Past site operations included a polyester resin plant, which generated styrene, polymers, silica, organic acids and ethylene wastes. These wastes were sent to an onsite incinerator, and others were stored in a hazardous waste storage area.
A Consent Agreement in 2005 required facility owners to draft several documents, and conduct soil, soil gas and groundwater investigations to determine if past site activities contributed to contamination.
These activities identified concentrations of naphthalene, cadmium, and lead in soil and benzene in soil gas. Further investigations concluded that these concentrations were limited but would require the use of a land-use covenant to restrict use to industrial purposes.
Confirming the concentrations help protect employees, while the land-use covenant adds another layer of public protection. In addition to the investigative confirmation sampling, two human health risk assessments verified the sampling conclusions.
“This kind of work goes to the heart of what DTSC does,” Lewis said. “The business can continue operate, current and future employees are protected and the land-use covenant prevents any future public exposure by restricting use.”
This Colton property is one of hundreds of cleanup projects that DTSC is involved with at any time. They come in a variety of sizes and are all over the state. Typically, the Department completes an average of 125 cleanups per year.