More Study Urged on Oil Well Hazards to Metro Rail

The danger of chopping into old, uncharted oil wells during tunneling for the proposed Metro Rail subway was among concerns expressed Monday by an independent panel of experts reviewing the safety of the project.

Wrapping up its second day of public hearings on the subway, the panel of geologists, engineers and mining experts agreed that the Southern California Rapid Transit District should further investigate ways of detecting abandoned wells and handling potentially explosive gases that could be spewed into the tunnel during construction.

While concluding that the $1.2-billion first segment of the subway can be constructed safely, the 10-member panel identified several areas where additional study is needed.

The panel’s report is expected to be forwarded to the Los Angeles City Council for review and action in the next few weeks. Made up of appointees of Council President Pat Russell and Rep. Henry A. Waxman (D-Los Angeles), the panel was created after Waxman, an influential supporter of the project in the past, raised questions about the safety of tunneling through underground gas pockets. Much of the route is in Waxman’s district.

RTD Battling Administration

The panel’s concern about abandoned oil wells comes as the RTD is battling Reagan Administration opposition and struggling to secure multiyear funding from Congress so construction on the much-delayed project can begin early next year.

Noting there are many old, unidentified wells in the Los Angeles area that were poorly sealed when they were shut down, one panelist, engineering geologist Eugene Waggoner, said the old pipes are a “chaotic mess.”

While panelists agreed that it is unlikely, they expressed concern that the huge tunneling machine could unexpectedly rupture an old well casing, which could act as a “pipeline” from a lower gas field and release high pressure methane. If the gas is ignited--possibly by sparks from the machine striking the well casing--there would be an explosion or fire that could injure workers, panelists said. Such an explosion would almost certainly be confined to the tunnel, panelists said.

Even if the gas were not ignited, it could pose a hazard to workers by displacing oxygen deep in the tunnel, panelists said.

RTD officials acknowledged that old wells pose a special problem, particularly because there is no proven way to detect them ahead of the tunneling machine. “We know they’re out there,” said James Crawley, director of engineering for the transit agency, which will build and operate the downtown-to-North Hollywood subway. “But we’re dealing with an unknown. (The risk) is difficult to quantify.”

Crawley and other RTD engineers have argued that they will address the problem by heavily ventilating the digging area, extensively using gas monitors, providing workers with air supply packs and drilling probe holes ahead of the tunneling machine.

But the panelists said Monday that more work needs to be done to locate the wells and prepare for a worst-case possibility.

Other recommendations by the panel include more study of how to:

- Quickly identify when the tunneling machine is crossing an active earthquake fault that could act as a conduit for methane gas.

- Better identify where the water table is in relation to the tunnel route.

- Improve plans for evacuating the handicapped and elderly from the trains in an emergency.

- Provide a completely independent backup power supply to run the extensive tunnel ventilation system in the event of an areawide power outage.