Supervisors OK Rules That Freeze Pollutant Discharge Levels : Air quality: The plan allows for economic growth through a system of credits for cutting emissions. The credits can be used for expansion or sold.

The Ventura County Board of Supervisors on Tuesday approved air-quality rules that freeze at today’s levels the amount of ozone-forming pollutants that business and industry can discharge.

The strict new standards, required by a 1988 state law, represent the first time fast-growing Ventura County has committed to holding air pollution from businesses at current levels even as the county’s population continues to grow.

The new rules allow for economic growth through a system in which companies that cut pollution--generally by using more efficient engines--earn credits that they can use to expand or can sell to other companies.

A version of this system was created in 1979 by the county’s Air Pollution Control District, and more than 1,000 tons of pollution credits have been accumulated by eight large companies, officials said. The going rate for a ton is about $10,000, they said.

The system approved Tuesday includes a new element--a so-called “community bank,” which will receive 25% of existing credits and 20% of all credits claimed by large companies from now on.

The community bank will distribute the credits free to small businesses, so they can continue to move into the county, and to enterprises that benefit the public.

The new rules are a key supplement to the county’s overall pollution-control plan, which was approved by the supervisors two weeks ago.

Even with the new rules and a variety of other pollution-cutting measures approved over the last year, Ventura County falls far short of meeting state and federal air-quality standards.

Altogether, the new strategies are expected to reduce pollution-causing emissions by one-third by the end of the century, far less than the 50% to 70% needed to meet federal and state standards.

And the new rules approved Tuesday call only for no net increase in pollution from business and industry, said Pat Baggerly, a director of the Ventura County Environmental Coalition.

“It’s not a decrease in pollution,” Baggerly said, “so it’s hard to say, ‘rah, rah.’ ”

The county violates federal standards for ozone, a primary component of smog, 44 days a year and more-stringent state standards 130 days a year, county officials said. Air pollutants in the county are otherwise within federal guidelines.

Ozone, created when nitrogen oxide combines with hydrocarbons in sunlight, can cause lung and respiratory damage.

Vehicles cause about 50% of the county’s ozone. The new rules place greater restrictions on a variety of other polluters that are stationary--everything from oil fields to power plants and dry cleaners.

For example, the new rules require that all businesses buy machines with the best available technology when they replace old equipment or expand operations.

This requirement prompted an objection Tuesday by a representative of the Navy’s Pacific Missile Test Center at Point Mugu. The Navy asked, but did not receive, an exemption from county rules for four diesel generators that it plans to replace at its San Nicolas Island tracking station.

“It turns out that those four engines out there are uncontrolled (for emissions), and are one of the largest sources of nitrogen oxide in the county,” said Keith Duval, a manager who oversees development of new pollution-control rules.

The estimated cost to replace the Navy generators with the best low-polluting equipment is $1 million, Duval said.

The Western States Petroleum Assn. has also said the best-technology requirement is unnecessarily costly.

“We wanted to be able to replace a steam generator with an identical steam generator if there was no net emission increase,” spokeswoman Aeron Arlin said in an interview.

The best-technology requirement might have a bigger impact on small dry cleaners, where replacement of older equipment would cost $5,000 to $10,000 but where low-pollution machines cost $20,000, Duval said.

Nearly all testimony at Tuesday’s hearing was about an obscure provision of the new rules that would have allowed owners of new landfills--not just existing ones--to receive pollution credits free from the new “community bank” because the methane gas flaring systems required at the dumps benefit the public.

Opponents said the provision was a subsidy for companies such as Waste Management of North America, which has proposed building a landfill in Weldon Canyon north of Ventura.

The supervisors rejected the provision, saying that it could possibly be added when the rules are revamped again within a year to include federal guidelines now being drafted.