More than a month after a methane explosion rocked the Fairfax area, officials of the Los Angeles Unified School District have found high levels of the potentially dangerous gas under the asphalt-covered playground of nearby Hancock Park Elementary.
School Safety Supervisor Jack Waldron said that the 440 children attending Hancock are in no immediate danger because the methane is not seeping into the school building where it could become trapped and explode as it did on March 24 in the basement of a discount clothing store a quarter of a mile away. The school, not affected by the blast, was closed for three days.
Seepage Monitored Daily
The gas seepage at Hancock Park is being monitored daily at 46 holes scattered around the school yard. Because the gas dissipates rapidly in the open air, officials said it poses no health problem for children. However, several trees and other plants are stunted and dying.
Concern that other schools in the district--located near oil fields, former oil drilling sites and landfills--may be endangered by the seepage of methane prompted district officials to announce plans to survey 181 school sites. The names of the schools--including more than 40 in the western section of the district--were released Friday. Hancock Park is the first school on the Westside to be monitored daily.
"We are concerned about the kind of situation we had in the Fairfax area and we felt it was prudent to take a look at all our schools in areas where there may be migrating gas (underground)," Waldron said.
Gas in Gym
A few days after the Fairfax explosion, the district detected methane in the gym of Francis Polytechnic High School in Sun Valley. A similar problem was discovered in Arminta Street School in North Hollywood. Both schools are located near landfills.
To identify the 181 school sites located near possible methane sources, the district obtained geological records and information from municipal sanitation departments. School officials will drill holes in the ground and insert hand-held probes to measure gas levels at each school.
Methane, a principal ingredient of natural gas and a byproduct of decomposing trash, is potentially explosive in concentrations of between 5% and 15% of the air. Above 15%, it will not explode, but it will burn. "You need to have the right amount of methane and an ignition source for it to explode," Waldron said.
Ignited by Spark
Fire officials believe that the March 24 explosion in Fairfax was the result of methane fumes from an old oil and natural gas field that seeped through a clay dome 50 feet below the earth's surface. Some of the gas became trapped in the basement of a discount clothing store and was ignited by an electric spark.
Not Certain of Cause
Bill Piazza, a school safety environmental specialist who tests the gas levels at the Hancock school, said officials are not certain why the gas has been detected in high levels in the school yard but not inside or under the school just a few feet away.
"We are just finding out about this," Piazza said. "We just don't know that much" about the potential for explosion from underground gas deposits.
He said district officials plan to look at geological studies done when the school was built in the 1930s. "Maybe they knew something back then that could help us now," he said. "We found that the ground in the yard is moist and damp, but the ground under the school is more solid. . . . It could be that the gas cannot penetrate the soil under the school."
Waldron said the district plans to eventually replace its current method of "manually" reading gas levels with a computer monitoring system that will produce printouts on gas movement.
Westside-area school officials plan to survey Arlington Heights, Baldwin Hills, Bancroft Junior, Blend Special Education, Burroughs Junior, Canfield Avenue, Carthay Center, Coeur D'Alene, Fairburn Avenue, Fairfax High and Hollywood High.
Also Laurel, Le Conte Junior, Los Angeles High, Marina del Rey Junior, Melrose Avenue, Mt. Vernon Junior, Palms, Queen Anne Place, Rosewood Avenue, Santa Monica Boulevard, Selma Avenue, Short Avenue, Van Ness Avenue, Vine Street and Warner Street.
Also Westminister Avenue, Westside Alternative, Wilshire Crest, Wilton Place, Windsor Hills, Charnock Road, Gardner Street, Grand View Boulevard, Mar Vista, Overland Avenue, Palms Junior, Playa del Rey, Roscomare Road, Richland Avenue and Venice Skills Center.