Vulnerable to Vapors

As if earthquakes weren’t enough, there’s another invisible danger lurking beneath the Los Angeles Basin, from Newport Beach north to Newhall.

It is methane--a colorless, odorless, highly explosive gas naturally produced by the 70-odd oil fields on top of which much of the metropolitan area is built. The fields are primarily clustered along the area’s major fault lines, where oil seeps out of ruptured rock.

So, if your community is built on or near a fault, there’s a good chance it’s also sitting atop abandoned oil wells--and methane. If not properly vented, the gas can work its way through even concrete foundations and cause disastrous explosions.

For decades, as Los Angeles and its environs have evolved from an oilman’s Eden to developer’s heaven, three-quarters of the area’s 33,000 oil wells have been abandoned, and the risk of trapped methane gas under the surface has grown.

The latest example is the half-finished Belmont Learning Center in Los Angeles, a $200-million high school project that has been stopped in its tracks by belated official recognition that methane is seeping up from the earth beneath the site. If the methane problem cannot be solved, the school district may be forced to abandon the costly project.

Along the portion of Orange County’s coast that roughly coincides with the Newport-Inglewood fault, everyone from hospital construction teams to developers of gated communities are taking measures to reduce the threat of methane--or to harness it as an energy source.

The reason is simple: “The only open space left to build on . . . is the open oil fields, so people are building there,” said Richard Baker of the state Division of Oil, Gas and Geothermal Resources. Baker oversees construction permits for Orange and Los Angeles counties that make sure old wells are properly capped and vented.

Ironically, when it comes to methane, it’s better to have pumping oil wells in residential areas than abandoned wells without proper venting. Once a well is abandoned, or even sitting idle, “what Mother Nature did to create the oil field, Mother Nature is going to continue to do--fill that oil field back up,” Baker said.

And with the seeping oil come swelling methane fumes. If they find a weak link in an old well, where air mixes with the fumes, they can and do explode outward, ignited by as little as a light switch being flicked on.

“If you have oxygen and gas and a spark, you get an explosion,” Baker said.

It is impossible to know how fast an area of an oil field will repressurize, but there are telling examples.

In 1973, a Newport Beach cottage owned by a retired sea captain began filling up rapidly with crude oil.

The culprit was an abandoned oil well directly below.

The force of oil rising from the improperly sealed well cracked the concrete foundation and flooded the kitchen.

The house was partially torn down to get to the leaking well and properly cap it.

Several years earlier, a real estate agent preparing to show a house in Balboa Coves sparked an explosive fire by turning on a light switch.

No one was killed, but the house was gutted in the blaze, which was attributed to trapped methane from an old well.

The most damaging of such incidents in recent years was a March 1985 methane explosion in a discount clothing shop in the Fairfax district of Los Angeles that injured 24 people.

The explosion led to quick passage of legislation that set aside funding for testing and other steps to stem the threat.

He said an estimated 140,000 cubic feet per day of gas shoots out of the earth’s crust at that particular spot.

Today, as part of a $1-million methane mitigation project, the blue flame so familiar to longtime county residents is no more.

Instead, the fumes pouring out of the underground field are funneled through underground pipes, and scrubbed clean of the more toxic hydrogen sulfide.

Then they are either vented through a tall chimney, or funneled into pipes that run into hospital boilers.

Officials said the fuel will never provide all of the hospital’s power, but could help.

A thick plastic liner also was laid under the concrete foundation of a new administration building to prevent any methane seepage.

Hoag hospital is right across the highway from the neighborhood where the real estate agent turned on the light switch and blew up the house, and the hospital pumps out methane from under those houses now as a community service, according to Reveley.

No state law requires that permits be obtained to build on top of oil fields.

But many city and county building laws require approvals from the state oil and gas office before they will issue permits.

The office used to receive 40 or 50 applications annually 15 years ago. They now review 1,200 per year.

Each developer must obtain oil-well maps from the state office, then excavate the site to determine if and where the wells are on the property.

Any leaking well on the site, even if it is not near the planned building, must be reported immediately, and all wells under houses or businesses must be vented.

State engineers test for leaks and inspect capping and venting procedures before issuing a certificate that the developer must present to city or county building permit officials.

“We will always tell people, with the earthquakes, ground settling, all kinds of dynamics going on underground, the best way to mitigate is don’t build over oil wells,” Baker said. If they must build on them, then they need to vent, he said.

Upscale Huntington Place in Huntington Beach offers a good example. On the sidewalks in front of the million-dollar homes in this gated community are tall, spindly concrete structures that look like lampposts without the lamp on top. They are methane vents.

“We signed a disclosure report saying we’d been told that was to vent the gas,” said Cindy Lang, who moved in with her family two months ago.

“I’ve never noticed any smell or anything. . . . You could just worry yourself away about every little thing--earthquakes, floods, oil--or you can just live in the house you want and not worry.”

Times staff writer Edward Boyer contributed to this story.

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Oil and Trouble

Oil drilling is a century-old fact of Southern California life. Edward Doheny discovered oil in 1892 west of downtown Los Angeles, just blocks from the Belmont Learning Complex site. Pools of black gold may harbor the risk of potentially explosive methane that can seep to the surface, making measures to control it important in construction codes.