A county planning commission hearing to evaluate the plant?s noise impacts was delayed last week, so a planned Board of Supervisors meeting on March 24 has been postponed until after the commission hearing is held, county staff said.
The decision means the board?s 4-1 straw vote on the plant won?t be confirmed until late spring, which opponents hope buys them more time to convince at least two supervisors to change their minds.
But the project?s builder, Dutra Materials, said the delay allows the company to present revised noise mitigations for the 38-acre asphalt plant site, which would also include a concrete crusher that turns rubble into re-usable aggregate.
Company CEO Aimi Dutra said a soundwall within the site, between the railroad tracks and the Petaluma River, will be increased from 12 feet to 16 feet in height.
That will reduce noise heard at Shollenberger Park, across the river, to levels ?at or below? county noise standards, she said.
The environmental impact report for the project said as originally designed, noise standards would be exceeded at two locations along the park?s walking path.
The county planning commission hearing, now scheduled for April, will determine if the project can exceed noise standards for two riverside residences at Haystack Landing, a onetime shipping port near the Petaluma Boulevard South off-ramp of northbound Highway 101.
The project would produce 664,000 tons of material a year, including 225,000 tons of asphalt. About 150,000 tons of concrete would be brought to the site each year for recycling, which the company said would reduce the need to mine new material.
Supervisors tentatively approved the plant after a seven-hour hearing on Feb. 3, asking for additional enclosures and landscape screening to reduce the project?s impacts. Dutra said the company has agreed to those requests.
Opponents of the plant, meanwhile, say they are continuing to gather signatures from local residents, and are now asking teachers and parent groups to join their cause. The City Council voted unanimously in January to oppose the plant.
?Our message continues to be, it?s the wrong plant in the wrong place,? said Joan Cooper, of Friends of Shollenberger Park.
A group called Petaluma Moms for Clean Air is also opposing the plant, and asking local schoolteachers and parents to do the same. Organizer Julia Luna said 180 letters have already been sent to the county expressing concern about the plant?s emissions.
Although the EIR for the project found that harmful emissions and ?blue smoke? from the production of asphalt would be contained and not escape into the air, opponents fear the cumulative impacts of emissions from diesel trucks and machinery at the site.
The impact from diesel emissions at the plant itself would be insignificant, the EIR found, but could add to a cumulative impact on the region.
The county ?is not looking at the overall impacts from the entire area,? said Petaluma Mayor Pamela Torliatt, who serves as chair of the Bay Area Air Quality Management District?s board of directors.
Supervisors would have to adopt ?overriding considerations? in order to approve the plant?s ?significant and unavoidable? impacts, county staff have said.
Opponents say that step ? combined with the need to amend the county General Plan and zoning regulations to allow the plant ? shows that the project location is simply wrong.