Board Backs Regulation of Oil Rig Emissions : Environment: Supervisors grant the new authority to the county’s air quality district. Federal approval is expected.

Ventura County air pollution officials may soon have the power to order reduction of smog-forming pollutants at four offshore oil rigs, which would end a long battle over control of offshore air pollution.

The Ventura County Board of Supervisors on Tuesday approved a procedure that allows the county’s Air Pollution Control District to impose the same air pollution controls on the offshore rigs that it already does on onshore operations.

However, final approval of the district’s new authority will not come for another 60 to 90 days, when the U. S. Environmental Protection Agency is expected to grant permission, county officials said.

Even then, Unocal Corp. and Chevron USA, which each operate two of the four platforms off the county’s coastline, will have until September, 1994, to meet the new requirements imposed by the district.

The stronger regulations are required by amendments to the Clean Air Act, passed by Congress in 1990, which give the EPA authority to regulate air emissions at the offshore rigs. The action taken by the supervisors sets the stage for the EPA to pass that authority on to the local district.

The plan to give the district the new regulatory power met no resistance Tuesday from Unocal Corp. or Chevron USA.

Jim Lovins, environmental specialist for Chevron, said local control--rather than EPA control--of the new regulations will cut down on red tape and time for industry officials.

“It will take out one level of government review,” he said.

“We don’t see a problem,” Unocal spokeswoman Janet McClintock said.

That is not to say that oil company officials are happy about the stronger regulations. They voiced heavy objections two years ago when the regulatory authority over air pollution from offshore platforms came under the EPA’s wing. Before that, it had been the responsibility of the Interior Department’s Minerals Management Service, which also is charged with promoting oil and gas leasing.

Chevron expects to put $1.3 million into retrofitting platforms Gail and Grace so that they comply with onshore air pollution regulations, Lovins said.

For Unocal, the cost of upgrading platforms Gina and Gilda will be less than $500,000, McClintock said. It will cost the company another $50,000 a year to continue to stay in compliance with the regulations, she said.

The two companies are working on compliance plans, due by September, 1994, which will detail how they will reduce air pollution from the platforms and the boats that service them.

If the plans satisfy district officials, they will issue new operating permits.

“The law is here and we’re making it as easy as possible for them to comply,” said Richard Baldwin, the county’s air pollution control officer. “Nonetheless, they have to comply.”

In general, applying onshore air-pollution regulations to the offshore platforms is expected to reduce the ozone-causing pollutants that they emit by about 75%, county officials say. Those pollutants--some of them caused by diesel engines on the platforms that generate electricity to pump oil from beneath the ocean floor--are carried onshore by prevailing winds.

“We have a serious air quality problem,” said Baldwin. “We have some of the highest ozone levels in the nation.”

However, ozone-causing pollutants from the platforms represent less than 1% of the county’s inventory of known pollutants, according to county officials.

The four platforms are located four to 12 miles offshore and fall within a 28-mile enforcement area. The new regulations cover a variety of operations on the platform--everything from modifying gas-powered turbine engines to checking for leaking valves and pipe connectors.