It is still not clear if the leak was of propane or butane -- both materials are stored at the facility at 2110 N. Gaffey St. -- and an investigation continues into the cause of the incident, an air quality spokesman said Friday.
"We issued a violation (to the company) for what we call a public nuisance due to foul odors," said Sam Atwood, a spokesman for the South Coast Air Quality Management District.
The facility owners, Plains LPG, could not be reached for comment.
A violation is issued when the agency receives complaints from a "considerable number of people" and the source can be traced to a facility by an AQMD inspector, Atwood said.
"We ended up getting 37 complaints from a pretty wide area, including San Pedro, Carson, Torrance, Harbor City, Wilmington, Lomita and Rancho Palos Verdes," he said.
The agency also received complaints that day from four schools: Eshelman Elementary, Fleming Middle and Narbonne High schools in Lomita; and Hickory Elementary School in Torrance.
"We did take some air samples and they were mostly the kinds of levels you'd expect to see anywhere around Southern California," Atwood said. "There were a couple of compounds that were somewhat elevated, but they were not at levels that would be considered toxic in relation to state health or safety standards."
Some levels were sufficient, however, to have caused symptoms such as nausea and headaches, he said.
The complaints reported "foul odors of a various nature, including natural gas, propane, rotten eggs and suffer," Atwood said.
When the AQMD investigation concludes, the agency and company will then enter into negotiations for an out-of-court settlement, reached in "well over" 90 percent of cases, Atwood said.
"First they have to fix whatever problem caused the violation and we have to be satisfied that this is not something that's going to occur again," he said. "If the problem is with improper maintenance, we have to be satisfied that it's been remedied."
Established in 1976 by Petrolane and later operated by Amerigas, the facility is now owned by Plains LPG, which has a long-term lease on the land. The facility stores 25.3 million gallons of butane and propane in two large, double-walled storage tanks on the site.
The facility has come under fire through the years by community groups and others who believe it needs to be moved away from homes and schools.
When a gas line exploded in San Bruno in 2010, members of the San Pedro Homeowners United group renewed a call for the tanks to be moved, citing the potential danger that could come from earthquakes and terrorist attacks.
Currently, the plant is the subject of frequent safety inspections by several government agencies.
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