As crews inch toward a permanent seal of the Porter Ranch gas leak, Los Angeles County officials called Monday for a series of air-quality tests that will tell residents whether it's safe to return home.
Los Angeles County Supervisor Michael D. Antonovich joined the chorus of public officials pushing for additional air pollutant tests in Porter Ranch, saying the Department of Public Health should conduct spot checks in homes before residents return to the area affected by the methane leak.
After the leak at an Aliso Canyon well was reported Oct. 23, some Porter Ranch residents evacuated their homes complaining of dizziness, headaches and nausea. Before moving back, residents should know whether the methane plumes left any "residue" outside or in their homes, said Antonovich spokesman Tony Bell.
In an email Tuesday, a Department of Public Health spokeswoman said officials are reviewing Antonovich's request, and expect "to develop a proposed testing procedure within the next several days."
Sen. Barbara Boxer, echoing the concerns of resident groups, said the tests should be conducted by a private organization, the U.S. Environmental Protection Agency or the South Coast Air Quality Management District.
On Thursday, Southern California Gas Co. crews stemmed the plumes of methane by injecting heavy fluids and mud into a relief well that intercepted the damaged one. They have since replaced the temporary plug with layers of cement, which, once dry, should permanently seal the leak.
Gas leaks are invisible to the naked eye, but a dramatic infrared video released by state air-quality regulators last week showed gas billowing into the atmosphere. That's left some residents uneasy.
"We want to tell people that there's something there, or that there isn't something there," Bell said.
Once the cement inside the relief well dries, regulators with California's Division of Oil, Gas and Geothermal Resources will certify that the leak has actually stopped. That process could take several days.
After that, Porter Ranch residents who left the area for hotels and temporary apartments will have eight days to come back home. Anyone who signed a lease on a house or apartment will be allowed to stay through the end of the rental period.
A Southern California Gas Co. representative said Monday that the company is "working to stop the leak as expeditiously and safely as possible."
The AQMD and the California Air Resources Board say they will also continue to test the air for methane and other pollutants.
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