Vinyl Chloride Detected in Houses Near Landfill : Environment: Low levels of the cancer-causing gas are discovered in three Montebello dwellings in the vicinity of a closed dump, one of the nation’s most polluted sites.

The U.S. Environmental Protection Agency has detected low levels of cancer-causing vinyl chloride in three Montebello homes near the now-closed Operating Industries Inc. landfill, one of the nation’s most polluted sites.

The levels detected during testing last month did not require evacuation of the residents, EPA officials said Tuesday.

“It was below the evacuation level but it was above a level acceptable to the EPA,” said Janet Whitlock, an EPA project manager.

The EPA has installed a vent pipe coupled with a fan under one of the homes to keep the contaminated air from seeping through the home’s foundation and into living quarters, Whitlock said. Similar systems will be installed in the other homes later this week.

Only small amounts of the gas are expected to be vented into the atmosphere, amounts that do not present a significant health risk, Whitlock said.

The EPA, citing reasons of privacy, did not release the addresses of the homes where the toxic gas was found. No vinyl chloride was detected in 34 other homes tested last month.

The EPA decided to test the homes after monitors on the perimeter of the landfill detected small amounts of vinyl chloride.

Vinyl chloride is used in the manufacture of plastic products that may have been dumped in the landfill. It also is created as chemicals break down in the landfill.

Air samples will be taken from another 50 homes near the landfill beginning this weekend. In all, the EPA plans to test about 200 homes by February.

The EPA also is monitoring for methane, a potentially explosive gas that is generated by decomposing trash. But high levels of methane were not detected in any of the 37 homes.

Hank Yoshitake, a community activist who campaigned to have the former dump cleaned up, said residents were worried but thankful the EPA has taken action to protect their health.

Yoshitake’s Yorktown Avenue residence, about half a block from the dump, was one of the 37 homes tested. No vinyl chloride was detected, he said.

“We’re always concerned about anything that is bad for the neighborhood,” Yoshitake said. “We’re relying on the EPA to find these homes that do have small traces and to mitigate it.”

The OII landfill is in Monterey Park, on Montebello’s northern border. It accepted industrial, residential and commercial waste from 1948 until it was shut down in 1984 amid community protest. Hazardous liquid wastes were dumped there from 1976 to 1983.

The site is on the national Superfund list, which identifies the most contaminated sites for priority cleanup. EPA officials say it will cost more than $200 million to make the site safe. That will include capping the landfill, which should be completed in about four years, and installing a gas control system to prevent leaks. Gas extraction wells are already on the borders of the landfill to limit emissions.

“The final remedy is under design,” Whitlock said. “That will ultimately take care of the landfill gas problem.”

A plant to treat leachate--a dark liquid generated by decomposing trash, liquid waste and rainwater--has been built at OII and is being tested. It is expected to go into operation in the next few months, said Roy Herzig, another EPA project manager at the site.

Testing continues to determine the extent of ground water contamination associated with the dump. Officials expect that the site will have to be maintained for at least 30 years.