The leaking, 40-year-old gas pipeline that prompted last week's evacuation of about three dozen Arvin residents, some of whom had been sickened, was never inspected because, at just 3 inches in diameter, the pipe falls below state and federal standards that would require such testing, officials said this week.
The field-gas pipeline is not covered under federal regulations by the U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration for a second reason as well: Because it is neither a transportation line nor a production line, PHMSA spokesman Damon Hill said, federal regulations do not apply.
Those factors didn't make some of the displaced Arvin residents any less sick, though. Subjected to toxic gas levels as high as 13 times the upper safety threshold established by the U.S. Environmental Protection Agency, many have complained of headaches, nosebleeds and coughing over the past several weeks and months. The gas-level reading was taken by by the Arvin Bucket Brigade, a local nonprofit that gathered and then sent the air samples to a state facility for testing.
The California Department of Conservation's Division of Oil, Gas and Geothermal Resource requires only that pipelines be regularly tested if they are more than 4 inches in diameter. The leaky pipeline, owned by Petro Capital Resources LLC, is only 3 inches in diameter.
The line that leaked is a low-pressure transfer pipeline that carries gas associated with oil production from one oil field to another. It carries that gas to a location where it can be flared off.
DOGGR believes it was built in the early 1970s. PCR has owned it only since 2012.
DOGGR has no record of the line ever being tested for leaks by PCR or any of the line's prior owners. It is unclear how long the line has been leaking, but some residents said they've smelled the gas for years.
PCR Production Manager Jeff Williams, who said his company has workers out at the oil wells every day, couldn't explain how it had been overlooked for so long.
"I can't really answer why it went unnoticed, " Williams said.
When PCR bought the lease, no map was provided and the owners were told the line ran south, according to DOGGR officials. Once the leak occurred, PCR learned that the line actually ran north.
It was Southern California Gas Co. that initially detected the leak, which led to the mandatory evacuation of eight homes March 18.
On March 12, Southern California Gas was performing routine checks for leaks on its nearby natural gas lines, said Javier Mendoza, spokesman for the company.
When the instruments detected gas, the Southern California Gas workers realized it was not coming from one of their pipelines. Southern California Gas then notified the city of Arvin and Kern County Fire Department.
Kern County Fire responded March 12 after receiving the call but at the time did not realize the line, which is about a half-mile long and runs beneath Varsity Avenue, was impacting neighboring homes, Kern County Fire spokesman Brett Grassi said.
It wasn't until March 17 that the homes on Nelson Court were tested and low levels of gas were found. Tests revealed that detectable amounts of flammable gases registered in 53 percent of the air space in one home; another home had detectable levels in 51 percent of its air space, Kern County Public Health Services Director Matt Constantine said.
The department responds whenever a 5 percent or higher reading occurs.
With the exception of the Varsity Avenue pipeline, all of PCR's lines are on rural, undeveloped land or undeveloped agricultural land and are both above and below the surface, Williams said.
Experts say while testing underground is more difficult, it can be done without digging up the line.
Randy Adams, who is retired from Bakersfield's DOGGR, said the standard way to test an underground line is a pressure test.
The company would connect a pressure device to one end of the line, block the other and fill the line with air, he said. Any pressure loss indicates a leak, Adams said.
The line has had a succession of owners over the years. Prior to PCR, Decker Brothers Inc. owned the line from 1998 to 2012; D & Y Oil Co. owned it from 1983 to 1998; Ed Green Operator had it from 1973 to 1983; and Gary Drilling Co. owned it until 1973, but records are unclear who built or bought it.
Toxins found in one Nelson Court house included methane, benzene, n-hexane, heptane and n-octane, according to the Arvin Bucket Brigade, a nonprofit independent air-testing program helping pollution-affected residents.
Four companies in Arvin have wells within city limits. PCR owns three wells, Sun Mountain Oil & Gas owns five wells, Vaquero Energy Inc. owns one well and Green Earth Resources Inc. owns one well.
Advanced GeoEnvironmental Inc., a private company, and Kern County Environmental Health are continuing to monitor for flammable vapors in the homes.
Installation of a primary vapor extraction system is under way and should be completed by the end of next week, according to a Kern County Fire news release. In the interim, the temporary home remediation system is currently in place and continues to dissipate trapped gas in the soil.
Advanced GeoEnvironmental Inc., hired by PCR, will continue to collect soil samples and wells for the primary extraction system will be installed starting Sunday. Completion of the system is expected by the end of next week, according to the news release.
PCR is paying for the evacuees' stay at the Residence Inn Bakersfield and offers $50 per day per person for expenses. The company has reportedly spent more than $30,000 on the displaced residents.
The cause of the leak will be investigated by Kern County Fire, Kern County Environmental Health Services and DOGGR, officials said.