Two California biomass plants fined for emissions violations

After completing a joint investigation, the U.S. EPA and the San Joaquin Valley Air Pollution Control District ordered two California biomass power plants to pay combined civil penalties of $835,000 to resolve alleged violations of the federal Clean Air Act and district rules, including excess emissions of air pollutants such as nitrogen oxides and fine particulates. 

The settlements require Ampersand Chowchilla Biomass LLC to pay a total of $343,000 and Merced Power LLC to pay $492,000. The companies are also required to go through multiple steps to ensure future compliance, including installation of devices to improve monitoring and reporting of air pollutants, enhancing automation of the control systems for nitrogen oxides emissions and preparing more stringent control plans to minimize emissions of air pollutants.

Both plants have already made progress in complying with EPA orders. The agency reported that so far, each have installed controls that reduce emissions of nitrogen oxides by up to 180 tons per year and carbon monoxide by up to 365 tons per year. EPA and the district will continue to monitor both facilities for an additional two years to ensure completion of all requirements, EPA said.

Both Ampersand Chowchilla Biomass and Merced Power are refurbished 12.5- megawatt wood-fired power plants that began operating in 2008, and are located within 13 miles of each other in the San Joaquin Valley south of Sacramento. Owned by Global Ampersand LLC, the power they generate is purchased by California’s Pacific Gas and Electric Co.

EPA spokeswoman Margot Perez-Sullivan said the plants were investigated on a case-by-case basis so the agency could not presume anything about Clean Air Act compliance of the biomass power industry in general. She said due to the confidential nature of EPA’s enforcement issues, it could not provide any additional details on the investigation.