Arco Dumping of Oily Waste Called Danger to Sewage Plant
An Atlantic Richfield Co. refinery in Carson improperly discharged millions of gallons of oily waste directly into county sewers, threatening explosions at a nearby treatment plant and resulting in the dumping of 350 million gallons of inadequately treated sewage into Santa Monica Bay, the Los Angeles County Sanitation District said Tuesday.
The county ordered the refinery’s connection to the sewer closed Tuesday until the company corrects the problem that caused the spill.
The oil spill occurred early Saturday morning and forced the closure of the sewage treatment plant’s secondary treatment system for 1 1/2 days. That resulted in the illegal sewage discharge into Santa Monica Bay, district spokesman Joe Haworth disclosed.
He added that refinery personnel apparently were unaware that they were pumping untreated oily waste directly into the sewer system until they were informed by sanitation district inspectors who had traced the source to Arco by late Saturday morning.
“We have suspended their permit and not allowed them to discharge into the sewer until they prove to us they have a fail-safe system and this will never happen again,” Haworth said.
Arco spokesman Al Greenstein said the suspension of the firm’s discharge permit would not interrupt refinery operations. He said that Arco expects the problem to be fixed within several days. In the meantime, he said oily wastes can be retained in holding ponds at the refinery or, if necessary, trucked to disposal sites.
The refinery, which employes 1,100 workers and was built in the 1930’s, processes 215,000 barrels of crude oil a day into gasoline, diesel and jet fuel.
Haworth said meters at the sewage treatment plant, which is also in Carson and processes effluent from other sources besides the refinery, detected explosive levels of gases about 4:30 a.m. Saturday. The plant’s secondary treatment system relies on pure oxygen, and operators, fearing an explosive mixture of the gas and oxygen, shut it down.
“All you have to do is imagine (the combination of) that explosive stuff and pure oxygen,” Haworth said.
With the secondary system out of service, only partially treated sewage was processed through the plant and dumped into the bay.
Federal and state ocean discharge requirements mandate that at least two-thirds of the sewage from the plant undergo secondary treatment to reduce the amount of organic material entering the ocean.
Haworth said sanitation district workers are still skimming the oil out of the plant. Greenstein said that Arco has taken out 150 vacuum truckloads of oily waste totaling 630,000 gallons from the plant.
Greenstein said that the oil company is not yet certain how the incident happened. But Haworth said the waste was funneled into the sewer through a temporary refinery pipe that Haworth said was not equipped with monitoring devices intended to measure the ratio of oil to water. The permanent discharge pipe, which has such a device, was being repaired at the time, Arco officials said Tuesday.
Both Arco and the sanitation district said that no oil appeared to have been discharged into the ocean.