County OKs More Homes Near Methane Gas Seepage

Seepage of methane from a closed landfill has raised concerns among some officials and residents at a housing development near Newport Coast Drive because high levels of the gas can explode if ignited under certain conditions.

But two county officials said Tuesday that the methane does not pose a danger to the residents who live in the luxury development.

The Orange County Health Care Agency is so confident in current methane controls at the landfill that it now agrees that building permits can be issued for 14 additional homes in the Rivage project, said Jack Miller, the county’s environmental health director. Until now, county concerns about the methane had delayed the permitting process.

The Irvine Co., which is building the homes, said that the methane remains about 30 feet below the surface and has not moved under the homes.

“But to ensure the public health and safety, extensive precautions are being taken to protect nearby homes and residents,” said Joe Davis, president of Irvine Community Development Co., in a prepared statement.

The county Health Care Agency issued a June order stating that a “potentially hazardous condition” existed at the landfill because of the leak and its proximity to proposed homes to the west.

All requirements of that order--issued to the Irvine Co., the county’s landfill agency and a private firm--have “been met or are on their way to being accomplished,” Miller said.

He said the term “potentially hazardous” in the June order referred to conditions at the Coyote Canyon landfill and not at the homes.

The Rivage homes, priced from $600,000 to $1 million, are being built on unincorporated Irvine Co. land near the former landfill, which the county operated from 1963 to 1990.

After the dump was closed, rules approved in 1995 required that the gas be controlled within the landfill boundaries, with regularly monitoring conducted.

When the Board of Supervisors approved the Rivage project in 1995, county officials and the Irvine Co. knew that some methane had seeped from the landfill site, an Irvine Co. official said.

The county imposed two requirements on the Irvine Co. at the time, said Tom Mathews, county planning director. First, the builder must prepare reports based on probes that methane is not exceeding the state-imposed level of 5% to 15% by volume in air, a measure used for gases, Mathews said.

Second, the homes were to be built with an elaborate system of barriers and vents, he said. Under the concrete foundation of each home is an impermeable membrane paired with a special venting system, he said.

“The Irvine Co. met all the county-imposed requirements in building the existing homes,” Mathews said.

The Irvine Co. said in a statement that “all home buyers are made aware of these systems, the presence of the landfill and the potential for methane migration in connection with the purchase of their homes.”

The Rivage homes are being built on a graded ridge near the landfill’s western boundary, with the nearest home about 250 feet away, according to the county’s June order.

That order was issued after testing in 1997 and early 1998 consistently showed “landfill gas had been and is still continuing to migrate off-site along the western boundary of the landfill,” the order states. “The levels of landfill gas were detected at levels between 5% and 70% of methane.”

The 70% figure came from a well that is several thousand feet away from the homes, said Irvine Co. spokesman Paul Kranhold.

County health officials emphasized that the methane remained 30 feet or more below ground and to officials’ knowledge has not moved closer to the surface. The gas appears to exist in pockets, which experts hope to remove through a so-called “air injection system” that has already been constructed. The county is evaluating the system and working out final details before it begins operations, Miller said.

Miller emphasized he believes residents are safe.”It was safe to occupy it, and it’s safe to continue,” he said.

One resident, Jean M. Donnelly, said that the presence of methane was disclosed to homeowners, some of whom then conducted their own research.

“I did consult environmental lawyers before we bought here,” said Donnelly, an attorney who moved into the neighborhood with her family in July. “A lot of people here looked into it extensively. They were convinced that the appropriate safeguards had been taken.”

Donnelly said she still feels comfortable that the methane seepage is being handled properly.

“I wouldn’t expose my children to a risk for a million dollars, if there was a risk,” she said. “We have confidence that it’s being handled properly.”