With construction of Los Angeles' newest high school nearly half done, school officials on Thursday disclosed that a new investigation of potentially explosive and toxic chemicals is required to ensure the safety of students and employees.
Environmental studies done during planning for the Belmont Learning Complex failed to detect problems with methane gas and other contaminants such as cancer-causing benzene at the former oil field where the school is now rising, officials said.
The new investigation and remedial work could extend construction time by several months and add millions of dollars to what has already become the most expensive high school in history, the district's environmental consultant said. So far, its cost is estimated at $200 million.
Construction has already been interrupted by the contractor's decision to wait for further testing before laying the concrete floor of a partially completed building of classrooms, said Angelo Bellomo, vice president of Environmental Strategies Corp.
The fear is that the concrete could block the escape of methane gas, causing it to accumulate in pockets that could ignite.
District Chief Administrative Officer David Koch conveyed Bellomo's recommendation for further study to the Board of Education in a letter Thursday.
Although the letter conceded that the high school would not open as scheduled in July 2000, it did not speculate on the length or the cost of the delay.
Board member David Tokofsky said he welcomed the heightened focus on student safety, which he believes had been brushed aside by "the expediency of the big project moving as fast as it possibly could."
Tokofsky said he and board member Julie Korenstein had raised questions about the dangers of construction in an oil field, but were ignored by district officials.
"Repeatedly there were analogies drawn to the Farmers Market explosion where the sidewalks caught on fire, just a year or two prior to the start of Belmont," Tokofsky said.
The 5,000-student facility is urgently needed to relieve crowding in one of the district's most heavily populated areas, just west of downtown. Once it opens, the current Belmont High, a few blocks to the west, will become a junior high school.
The developer is now exploring how the environmental work will disrupt its construction schedule.
"Right now it looks as if we can continue building the project and just modify our sequence of construction," said Ken Reizes of Kajima Urban Development.
Bellomo's assessment of the hazards at Belmont echoes a warning issued last month by the California Department of Toxic Substances Control. After reviewing partial records of the project, the state agency found that the potential hazards of building atop a turn-of-the-century oil field were not adequately studied before the start of construction on the 39-acre site.
The state review was prompted by Assemblyman Scott Wildman (D-Burbank), who has criticized the district's planning of the Belmont project and review of chemical hazards.
Acknowledging past lapses in environmental screening, district officials have agreed to let state inspectors take the lead in certifying the safety of sites for new schools.
Bellomo said the new Belmont inquiry began independently of state review after the construction firm detected methane "hot spots" this fall. Monitors detected methane "in places where we didn't expect to find it and concentrations we never expected to find."
A review of all available district documents revealed serious gaps in what was known about chemical hazards, Bellomo said.
An 11-acre portion of property initially purchased for a junior high school was extensively investigated with soil borings and vapor probes, Bellomo said.
But the addition of 28 acres, purchased when the district decided to build a high school, received less thorough scrutiny.
Three former oil wells were never located before construction began, Bellomo said. Another problem was the discovery of petroleum products floating on ground water near the surface below one of the buildings now under construction.
The source of the methane could be the abandoned oil wells or a natural seep of gas from deep oil deposits, Bellomo said. But the source could also be nearer the surface from oil byproducts left by drilling crews.
Methane poses a double hazard. When mixed with oxygen, either underground or at the surface, it can catch fire or explode. It also can carry other toxic chemicals such as benzene.
The initial exploration will involve drilling numerous holes to varying depths to collect underground vapors and soil samples and to monitor underground water.
Construction crews will have to avoid the drilling sites, and the contractor may decide to postpone any new work that could trap underground gas.
Once the problem has been characterized, the remedial work could include redrilling abandoned wells to fill them with concrete, installing pumps to suck vapor from the soil, removing contaminated soil and building collection systems under buildings to divert methane safely to the surface.
Bellomo said he is confident that technical problems can be resolved, reducing potential environmental risk to a very low level.