Gasket Rupture Halts Test Dig at McColl : Pollution: The EPA invites the public to tour the site today to hear about precautions for protecting Fullerton neighborhoods.

A test dig that began Thursday at the McColl toxic waste site came to a temporary halt Friday after a gasket broke outside a three-story tent erected to contain potentially harmful gases.

The problem was minor and no harmful gases were released, said John Blevins, an Environmental Protection Agency section chief.

The dig is scheduled to continue six days a week until sometime in the last week in June. The EPA will dig up about 135 tons of waste as a dress rehearsal for its preferred cleanup method, which involves digging up and burning an estimated 150,000 tons of waste.

Today, the EPA is inviting the public to tour the McColl site, on the south side of Rosecrans Avenue near Sunny Ridge Drive. Displays and officials will be on hand from 10 a.m. to 2 p.m. to explain the test and safety precautions designed to keep harmful levels of gases from escaping into surrounding neighborhoods.

The dig is taking place inside a sealed white tent pitched over one of the 12 toxic waste pits at McColl. Workers inside the tent wear protective clothes and breathing gear.

Air leaving the tent is filtered to remove harmful gases, and sensors have been installed to detect any leaking gases, EPA officials said.

The dump was created in the 1940s, when oil companies producing high-octane aviation fuel deposited refinery wastes in 12 sumps on land leased by oil industry consultant Eli McColl. Oil-drilling mud was later added.

The site lies beneath a vacant field and part of a golf course at the Los Coyotes Country Club and is bordered on three sides by homes in northwest Fullerton.

Since about 1978, residents of homes built just east of McColl have complained about odors and health problems that they say are caused by toxic gases from McColl. Two rounds of lawsuits over McColl have resulted in more than $24 million in settlements from developers and the oil companies alleged to have created the wastes.

Residents upset with delays in cleaning up McColl have been pushing for a solution. The EPA has said it will decide the best method for cleaning up McColl in the spring, although a complete cleanup will take at least seven years.

Before cleanup takes place, the EPA plans to try to force a consortium of five oil companies to pay cleanup costs. The oil companies, however, do not believe that they are responsible for cleaning up McColl, said William Duchie of Shell Oil, a spokesman for the companies.

“We don’t believe we are responsible parties, and we believe a court will find we’re not,” Duchie said.

Under federal law, the EPA has to show only that the companies produced the wastes that were dumped at McColl, said Jerry Clifford, deputy director of EPA’s hazardous waste management division.

If the companies refuse to pay for the cleanup, Blevins said, the process will probably be delayed during the resulting legal fight, but cleanup planning, a process that will take about two years, could continue during that time.

The companies--Atlantic Richfield, Phillips Petroleum, Shell, Texaco and Union Oil--have offered to seal off the waste permanently under layers of natural and artificial material. But state and federal officials have said they want the wastes removed.

The EPA is trying to force the companies to take over maintenance at the site, which includes a 24-hour guard and tests on ground water to see whether toxins are leaking.

The companies have until Monday to respond to the EPA’s demand, Clifford said.

The companies were preparing their response Friday, but will not release their decision until next week, Duchie said.