AUGUSTA – Ten percent of all the vehicles sold in Maine will likely have to meet strict new emissions standards beginning in 2009, according to the air quality program unanimously adopted by the state Board of Environmental Protection Thursday.

State environmental officials called the quotas – requiring six percent of all cars and trucks to have the newest emissions control technology, with an additional four percent of vehicles achieving the cleanliness achievable today only by gasoline-electric hybrids – “reasonable, flexible and achievable.”

The plan in question is known as the zero-emissions vehicle program, which is part of a set of California emissions standards that states can adopt. The air pollution controls are stricter than those mandated by federal law.

Maine has not been able to comply with the ZEV program in the past, because only fully electric cars, which aren’t practical for Maine’s geography and climate, met the requirements, according to Ron Severance of the Department of Environmental Protection.

California has since changed ZEV requirements to allow hybrids and clean-burning gasoline cars to count toward the 10 percent so long as 250 fuel cell vehicles are on the road nationwide by 2008.

Seven states, including California, have ZEV plans in place. The clean vehicles that meet the standards already are on Maine roads, Severance said, but more are needed to reap the environmental benefits.

Automakers who testified at Thursday’s meeting disagreed, arguing that Maine’s plan sets the bar too high, too fast. However, they declined to provide details about their production and sales estimates, saying that the revelation of such information could place them at a competitive disadvantage.

The board decided Thursday that a state compromise to allow automakers the chance to bank credits for compliant vehicles sold over the next five years sufficiently eased the industry’s burden to comply with the new requirements, which start in model year 2009.

Representatives of Daimler-Chrysler and General Motors were not satisfied, however, arguing that automakers deserved more opportunity to earn credits to place Maine on a level playing field with the states that adopted ZEV earlier and predicted that they would be unable to meet the standards.

They argued without success that the board should allow a second public comment period on the merits and shortcomings of the credits plan and offered to work with DEP in a stakeholder process to rewrite the plan.

Environmental groups, including the Conservation Law Foundation and Natural Resources Council of Maine, countered that clean vehicle technology has increased tremendously since California established its program, making it far easier for today’s companies to meet the emissions quotas without a running start.

Auto dealers could not sway the board when they argued that it might not be possible to sell the required number of clean cars – which would total about 5,500 vehicles, based on last year’s sales figures.

The demand for such vehicles is not guaranteed in Maine, where trucks make up 60 percent of all sales, said Tom Brown of the Maine Auto Dealers Association.

In response, Severance cited the six-to-eight-month waiting list for hybrids at some Maine dealerships and the fact that many of the most popular compact cars and small sedans already sold here actually meet the clean gasoline standard. Among those vehicles are some models of the Ford Focus, Subaru Legacy, Toyota Camry, Nissan Sentra, Dodge Stratus and Honda Accord.

“These cars don’t need an incentive to be sold. They’re being sold now,” he said.

Because it represents a major change to state law, the ZEV program must now be considered by legislators. If lawmakers approve the plan this winter, the quotas will take effect with the 2009 model year.

The board also gave unanimous approval to two other measures designed to reduce the emissions that contribute ozone problems, particularly in southern Maine, where pollution lingers above what is permitted by the federal Clean Air Act. All three measures approved Thursday are included in the state’s climate action plan, a blueprint for reducing Maine’s contribution to global warming, which is slated for release this morning.

Dozens of paints, varnishes and other products that meet the definition “architectural coatings” must now be formulated to reduce emissions of volatile organic compounds, chemicals that contribute to the greenhouse effect as well as increasing ground level ozone.

Pollution control technology will be required on the engines of heavy-duty diesel trucks (those weighing more than 14,000 pounds). The filters are set to be required federally, but 13 states are considering their own rules for fear the Environmental Protection Agency will bow to industry pressure and not implement the new standard. With this modern engine technology and the low-sulfur gasoline set to be mandated nationally by 2006, pollutants like nitrogen oxides and soot would be reduced by 90 percent, according to the DEP.