Water Is Tested : Solvent Leak at Northrop Taints Soil

A toxic industrial solvent being stored at Northrop Corp.’s plant in Newbury Park, near Thousand Oaks, has leaked into surrounding soil to a depth of at least 60 feet, health officials said Friday.

But test drillings in the area thus far have not found any contamination of water supplies, said Dana Determan of Ventura County’s environmental health division.

The cleanup could take several years, “possibly more if there is significant ground water contamination,” Determan said.

The leak of methyl ethyl ketone, a common industrial cleaner, was discovered six weeks ago when Northrop dug up five aging storage tanks no longer in use, Northrop spokesman Greg Waskul said.

“Four of the steel tanks had holes in them,” Waskul said. “Our people immediately began checking to determine the extent of the leakage.”

Tentative Plan on Way

He said Northrop on Monday will deliver a tentative cleanup plan to officials from the county, the State Water Quality Control Board and the California Department of Health Services.

Northrop employs 2,300 at the plant in Newbury Park, making it Ventura County’s largest employer. The division manufactures target drones for the U.S. Navy and parts for Boeing 747 airliners and F-5 fighter planes.

Determan, a senior sanitarian for the county, said that the contamination extends beneath the plant itself but that it was “very unlikely” that work at the plant would will be disrupted.

He said the nearest water well thus far discovered is about two miles from the plant and ground water near the plant “apparently flows away from that well.”

Further Reports Awaited

But he said state and county officials are not yet convinced that no wells have been contaminated and are awaiting further reports from survey teams.

Determan said that ground water in the vicinity of the plant usually begins about 60 feet below the surface but that several 60-foot holes dug by Northrop had yet to uncover any water.

Determan said he expects Northrop to propose a series of extraction wells to clear up the contamination over several years.

Northrop will pay the estimated cleanup cost of at least $250,000, he said.

Waskul said Northrop installed the tanks in 1961 when the plant was founded.

He said they were pulled out because “across the county steel tanks of this type and age have been found to leak almost 50% of the time, so our people thought we ought to check on them.”