January 6, 2003
Playa Vista Buyers Will Test Capability of Methane Shield
Critics call high-tech safeguards unproven. Courts back experts who devised system.
By Marth Groves, Times Staff Writer
Copyright 2003 The Los Angeles Times
Along with fancy appliances, swimming pools and sunset views, buyers at Playa Vista will be getting a few items not on the usual homeowner wish list: a huge rubber-like barrier beneath their homes, pipes that slice through outer building walls to rooftop vents, and a vast network of detectors and alarms.
Why all the high-tech hardware at the sprawling Westside development, which has just welcomed its first homeowner?
Because an undetermined amount of methane lies beneath the 2,500-plus townhomes, condos and houses under construction at the site, which is south of Marina del Rey at the foot of the Westchester bluffs.
Just how much danger the gas poses is the focus of die-hard opponents, who contend that it could accumulate to explosive levels inside buildings at the site.
Development of Playa Vista — on one of the largest parcels remaining on the city's choice Westside — has dragged on for a quarter-century because of challenges on issues from air quality and traffic to destruction of wetlands and endangered species.
In recent years, a few opponents have seized on the methane deposits, and the purported danger of explosion, as possibly their best hope for stopping the project. Their intense scrutiny prompted a review by city building officials and engineers that eventually led to a thorough revision of the city's code for gas-prone construction zones.
There is almost no common ground between opponents and those who favor the project.
Over the last decade, government agencies and courts have ruled repeatedly in Playa Vista's favor on methane and other issues. Engineers, builders and consultants for the project have joined the city of Los Angeles in saying the safety measures are the most elaborate the city has ever required — more than enough to prevent an explosion.
Foes of the development, however, continue to question how tests were conducted. They also say that the systems for monitoring and mitigating methane are unproven and could fail, threatening a deadly explosion in new homes and offices.
Raymond S. Chan, chief of the engineering bureau for the city's Department of Building and Safety, said residents and neighbors should not be concerned. "I would feel very safe putting my family in any building at Playa Vista," he said.
The opponents remain adamantly unconvinced.
"Where's the proof that any of this works?" asked Patricia McPherson, a longtime critic. "There's the illusion that there's some safety there, when there really isn't."
Quake Danger Cited
Opponents say one major danger is Southern California's unpredictable geology. A big earthquake, they contend, could damage the gas barriers and venting systems or rupture the underground layers of rock, sand and gravel through which the methane travels.
Moreover, they note, the task of keeping up the many vents, alarms and fans — at an unknown cost — will fall in coming decades to homeowner associations. Laypeople, Playa Vista detractors contend, are ill prepared to handle the job of maintaining such complex, technical systems.
But city officials say they are confident that the work can be done, with homeowners hiring consultants to keep the systems up to snuff.
In a sense, the new community's residents will be test subjects. Playa Vista's buildings are the first that must comply with detailed new citywide rules for "gassy" sites. In the next few weeks, officials expect to present the 50-plus pages of guidelines and a methane ordinance to the City Council, and they are bracing for a storm of protest from builders.
That methane exists at Playa Vista did not surprise engineers and geologists. Southern California has been one of the world's richest areas for oil production, which can be associated with the gas.
Consultants hired by Playa Vista suspect that the gas comes from the Pico Sands Formation, which extends from 500 to 3,000 feet below the surface. Gas gradually works its way to the surface along cracks or weaknesses in the rocks, occasionally bubbling up in creeks or pooled rainwater.
McPherson and her supporters contend, instead, that much of the methane at the construction site comes from a Southern California Gas Co. storage reservoir west of Lincoln Boulevard. That storage field is a natural formation more than a mile below ground where 7 billion cubic feet of gas can be held.
Project opponents allege that the gas mixes with toxic oil field gases and migrates eastward to Playa Vista — presenting a much larger hazard than would pockets of naturally occurring methane.
In reaching their conclusion, they have drawn in part on the opinions of M. Rasin Tek, a chemical engineer who consulted for the gas company in the early 1990s. In a 2000 deposition, Tek described the Playa del Rey gas storage reservoir as being "a little notorious" for allowing more gas seepage than a typical storage field.
Tek said Dennis D. Coleman, whose Illinois company analyzed hundreds of gas samples taken from Playa Vista, would back up his contention that the gas storage field was the likely source of Playa Vista's methane. But Coleman said his evaluation showed no evidence that gas around Playa Vista had come from the gas company's storage field.
Playa Vista and Southern California Gas Co. also strongly dispute Tek's theory, citing an analysis that they say proves conclusively that the Playa Vista methane is different from the gas from storage. Even some leading environmental groups opposed to Playa Vista — including Environment Now, Santa Monica BayKeeper and Wetlands Action Network — say the gas does not appear to be coming from the storage field.
One measure of the level of controversy attending Playa Vista has been a long-running feud over the work of Victor T. Jones III, the city's independent "methane peer reviewer" on the project from 1999 to 2001. Jones has been derided and praised by both sides.
In a 2000 report, Jones identified two sizable concentrations of underground methane, far more than the developer had reported. He advised that no building be allowed on the gassiest land.
Now Jones says his early fears have been laid to rest by numerous scientific assessments and by the city's decision to require the numerous safety measures he recommended. He once believed that gas was migrating to the surface along a "Lincoln Boulevard fault." He now says he agrees with geologists who found no evidence of such a fault and with gas analysts who say the gas company storage field is not the methane source.
"I'm not concerned with the project's safety," Jones said.
But Jones began working last spring as a part-time consultant for Playa Vista, a development that has reinvigorated opponents' claims that he is biased.
"For Victor Jones to be a consultant for them ... demonstrates that we have no real scientific and independent peer review," McPherson said.
Playa Vista officials said they hired Jones knowing that having the public's once "independent" reviewer on its payroll could look like a conflict of interest.
"We thought about this carefully," realizing opponents could say that "we were, in fact, co-opting him," said David Nelson, Playa Vista's vice president of environmental affairs. "We came to the conclusion that a sufficient amount of time had passed.... He's a smart guy, and he knows the site."
Methane is odorless and nontoxic. Its explosive potential was demonstrated in spectacular fashion in March 1985 when a worker punching a time clock (as one version goes) ignited methane that had accumulated in the basement of a Ross Dress for Less store in the Fairfax District.
The explosion injured 22 people and opened fire-belching fissures in the earth. The Fire Department let huge volumes of methane burn off for days.
More recently, the discovery of methane beneath the half-finished Belmont Learning Complex in downtown Los Angeles has created a controversy over whether the school can be safely completed. With the recent revelation of a fault below the $175-million high school, school district officials once again say they are leaning away from completing the project in its current configuration.
Still, city officials say Playa Vista, unlike Belmont, was built with ample advance knowledge and study. They credit McPherson and other opponents of the project with making their analysis the most thorough in Los Angeles history.
State rules require that buyers at Playa Vista be informed about the existence of methane beneath their homes.
The document for Tapestry townhomes includes a paragraph advising homeowners that they will be responsible for the costs of continuously running the methane-dispelling exhaust fans in crawl spaces. Buyers of Capri homes are advised that their detached single-family dwellings, priced at almost $1 million, have been designed with a gas-impermeable membrane and ventilation pipes.
The developer is not required to inform renters of such potential hazards, and has not.
The mitigation measures at Playa Vista represent a shift for city officials, who have made only limited demands in the past on builders with regard to methane, and only in the Fairfax District, Chan said.
"It's layer upon layer upon layer of redundancy," said Glenn D. Tofani, president and principal engineer of Geokinetics Corp., an Irvine company that is installing mitigation systems at Playa Vista. "It adds $10 to $15 per square foot to the cost of building, a cost that's passed on to customers."
Many of the mitigation measures will be invisible to residents because they are underground. Beneath the below-ground parking garages of the condos, pipes installed in gravel-filled trenches are designed to collect methane.
Above the gravel and pipe, builders have laid a membrane that has the appearance of thick stiff tar paper or a big sheet of rubber, depending on the type used. The membrane is designed to provide a gas-tight lid below the building.
The concrete foundations at Playa Vista are typically a foot or so thick — thicker and more heavily reinforced than those in most other Southern California buildings, Tofani said.
In areas with the greatest concentrations of methane, some pipes reach a full 50 feet underground, to "seek out" gas in a gravel zone that lies well below the water table.
Those pipes are designed to carry the gas to a series of solid, vertical "vent risers" that extend through the building walls and vent out the top of the building or come up directly through the ground.
Individual components of the system are furiously contested by opponents: The membrane could break and be difficult to repair, they say. The 50-foot vent wells will become clogged with groundwater and silt, they insist.
Nelson, the development's vice president for environmental affairs, said engineers have figured out how to pressurize the wells to keep them open.
Inside many of the venting pipes are gas detectors and flow meters, which monitor the concentration and rate of flow of any gas that is present. Gas detectors also are installed in underground or ground-floor parking garages.
Meeting Strict Standards
All parking garages must be ventilated, but the standard is stricter at Playa Vista. Should methane accumulate to 5,000 parts per million, the system is designed to activate the building's ventilation. That is just 10% of the so-called lower explosive limit of 50,000 parts per million.
If the gas reaches 25% of the lower explosive limit, an alarm is set to sound throughout the building and will be relayed to the Fire Department.
Playa Vista has established a secure Web site where voluminous methane readings for the development's visitor center and the already occupied Fountain Park Apartments are available to fire officials, Nelson said. Interviews with city officials revealed, however, that they have not yet agreed on how to deal with what will be a mountain of data.
Lloyd K. Fukuda, an inspector in the Fire Prevention Bureau, said most of the responsibility for monitoring the system and readings will rest with the developer and the Playa Vista homeowner associations.
"The Fire Department never agreed to monitor a Web site," Fukuda said. "Our responsibilities are to deal with an emergency if it does occur."
The city's fire marshal, Chief Jimmy H. Hill, later sought to clarify: "We don't know the level of responsibility that will be required. When the site is thoroughly built out, then we'll know" whether it is necessary to monitor gas levels daily or quarterly. "It would be speculative and a dire prediction to say what level the Fire Department needs to play at this time."
Methane readings from the visitor center and the Fountain Park Apartments, north of the for-sale housing under construction, have hovered close to zero for months on end, according to the company's secure Web site.
Inside the glossy visitor center on Lincoln Boulevard, prospective residents tend to show more interest in floor plans and prices than in methane. Playa Vista President Steve Soboroff views that as confirmation that all of the scrutiny is paying off.
"When people make a choice to live in what was the No. 1 oil-producing region in the world," Soboroff said, "then why not live in the place that has done the best mitigation and the place that has set the standard?"
Publish Date: January 6, 2003
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