As thousands of residents continue to shelter away from their homes in the Porter Ranch area, local air regulators have proposed a framework for minimizing and capturing the leaking natural gas spewing from a storage facility near the community.
Part of the plan calls for burning off much of the natural gas, plus the additive that gives it its smell, before it can waft into the neighborhood. Many of the residents who have relocated have complained that odor gave them headaches, nausea, nosebleeds and other ailments.
The terms of the proposed abatement order — released by staff of the South Coast Air Quality Management District on Thursday evening — were agreed upon by attorneys for the district and the Southern California Gas Company.
A spokesman for the AQMD said the district is satisfied with the plan it has sent for potential modification and approval to its independent hearing board. The board will take testimony on the proposal this Saturday in Granada Hills, starting at 9 a.m. at Granada Hills Charter High School.
“We’re pleased that we have reached an agreement so that we can present to the hearing board a number of, we think, strict conditions that the Gas Company has said that they have agreed to abide by,” said AQMD spokesman Sam Atwood.
The proposal includes requirements that SoCal Gas attempt to minimize and capture the escaping gas as quickly as possible, expedite removal of the remaining gas, provide additional continuous monitoring of the leaking well and report on all aspects of the effort to AQMD officials.
Other requirements stipulate that SoCal Gas would pay for the AQMD to conduct additional monitoring of conditions at the site and in surrounding areas. It also commits SoCal Gas to pay for research into possible health impacts from the escaping gas, its associated byproducts and any methods used to mitigate the odorous compounds.
“Residents are very concerned about potential health effects,” Atwood said. “Public health officials have said that they don’t anticipate any long-term effects, but this would be one way to scientifically study the issue and give residents some better assurance of whether or not there are any potential health effects involved with this incident.”
Raul Gordillo, a spokesman for SoCal Gas, said his company plans to install a pipe near the leak that would transport some of the gas to units that would either incinerate the gas or filter out odorant materials.
"The system is designed to be installed in two phases and, when fully operational, may incinerate up to 20 million standard cubic feet per day (MMSCF/day) or filter up to 14 MMSCF/day of natural gas," he wrote in an email.
Atwood said the methods will not completely address all the escaping gas.
“It’s not anticipated that the Gas Company will be able to capture all of the gas that’s leaking, and I don’t think we know yet even what portion is capable of being captured. We’re still a little bit in the preliminary stage in this,” Atwood said.
Atwood said some portable versions of the equipment could be in place as early as next week. Other larger-scale equipment, capable of treating larger quantities of air, will be subject to permitting and public comment.
There will also be tradeoffs associated with burning some of the escaping gas, including emissions of nitrogen oxides, carbon monoxide, fine particles and volatile organic compounds.
“It will destroy the methane. It will reduce that potent greenhouse gas. It should destroy the odorous compounds. As a trade-off, it will — as any combustion process will — produce some air pollutants,” Atwood said.
The specific terms of the abatement order could be altered by the hearing board, though Atwood said, even as currently written, the order would be effective.
“We think that this proposed order for the Gas Company — if adopted by our independent hearing board — is going to impose some strict conditions. And in the end, we hope that is going to reduce the foul odors that residents have been subjected to over these past several months,” Atwood said.
Attorneys representing local residents in a class action lawsuit did not respond to requests for comment on the proposed order.
This story has been updated.