The Los Angeles County Department of Public Health ordered Southern California Gas Co. late Sunday to stop cleaning the homes of Porter Ranch-area residents affected by the gas leak at the company's Aliso Canyon facility, concluding that the utility's contractor was not properly trained or equipped to carry out the cleanup.
The cleaning program was ordered Friday by L.A. County Superior Court Judge John Wiley, who ruled that the firm must perform remedial cleaning for up to 2,500 homeowners.
The health department said it sent environmental health specialists to monitor the cleaning performed by the utility's contractor over the weekend and determined that the contractor and the gas company were not abiding by protocols set forth by the health department.
A spokesman for SoCalGas said the company is working with the Department of Public Health to "immediately" address issues raised during the first day of the cleaning program.
"We are committed to coordinating with the Department of Public Health as they continue to provide details about how they interpret their protocol," said Chris Gilbride, spokesman for the utility.
Public health officials said they had asked the utility to meet Monday and discuss how the firm can correct its cleaning methods.
"The work will not resume until SoCal Gas provides necessary assurance that it can carry out the cleaning in compliance with the Public Health protocol," the health department said in a statement.
Testing by public health officials showed that the indoor air of Porter Ranch homes had no contaminants, but surface dust had low levels of metal contaminants that are similar to those found in the fluid used in well drilling. Officials said that finding suggested the dust came from the Aliso Canyon facility.
The sprawling storage facility near Porter Ranch was where one of 115 wells began to leak in October, releasing an estimated 100,000 metric tons of methane before it was plugged in February.
During the four-month leak, thousands of residents in the upscale community were forced to leave their homes and seek temporary housing because of health complaints and illness.
Because of the dust, public health officials urged residents to undergo a thorough cleaning of their homes and replace filters used in air conditioning and heating systems before returning. Residents relocated to hotels have until Wednesday to request cleaning of their homes, and those in non-hotel housing have until Friday to request cleaning.
Residents have 48 hours to return once the gas company cleans their home, after which the utility is not obligated to compensate for housing expenses.