Southern California Gas Company (SoCalGas) has been downplaying the number of air pollution tests indicating higher-than-normal levels of benzene spewing from its out-of-control gas leak near Porter Ranch, Calif., the Associated Press reported.
The natural gas leak has been billowing metric tons of greenhouse gases since Oct. 23, forcing the relocation of more than 5,000 homes in the Porter Ranch area, about 17 miles northwest of Burbank. The leak is being compared to BP’s Deepwater Horizon oil spill for its magnitude and environmental impact, prompting California Governor Jerry Brown to declare a state of emergency.
According to the AP, SoCalGas “understated the number of times airborne levels of the cancer-causing chemical benzene have spiked during the crisis.”
The company has been posting air sample results online twice daily. In its summary of the results so far, the SoCalGas said benzene has been detected at “extremely low concentrations … consistent with the levels expected for the area.”
The South Coast Air Quality Management District, which monitors air pollution and regulates its sources, says that average levels of benzene in the Los Angeles area are 0.1 to 0.5 part per billion. However, SoCalGas puts the average benzene level for the area at 2 parts per billion – up to 20 times the level cited by regulators.
Then, SoCalGas apparently used the elevated “standard” to make the gas leak seem less insidious. According to the AP, “SoCalGas originally said that benzene was found in amounts slightly higher than background levels in just two samples, both on Nov. 10. The suspect readings were 5.6 parts per billion in one gated development about a mile from the well and 3.7 parts per billion in the Porter Ranch Estates neighborhood of 1,100 homes.
“However, a more detailed look at the data by the AP and outside experts showed at least 10 other instances over seven days in November when benzene exceeded 1 part per billion,” the AP reported.
SoCalGas called the discrepancies “an oversight.”
The U.S. government and the World Health Organization (WHO) classify benzene as an undisputed cause of leukemia and other forms of cancer.
But the level of benzene exposure that is considered safe for humans seems to be a matter of opinion and can vary dramatically depending on who you ask.
SoCalGas puts that limit at 1,000 parts per billion over an eight-hour period. California’s environmental regulators set the limit at eight parts per billion for one hour of exposure for acute exposure and one part per billion over eight hours for chronic exposure.
According to WHO, there is no safe limit for benzene exposure.