The Maine Energy Recovery Co. will pay a $38,700 fine for failing a stack test at its Biddeford waste-to-energy plant last August.

The Maine Board of Environmental Protection this morning approved an agreement with the company on the fine. The fine also covered 23 other violations, including exceeding carbon monoxide emission standards 20 times and nitrogen standards three times during six years, said Bryce Sproul, licensing and enforcement director with the state’s air quality bureau.

The company passed a second stack test in October. The company was fined $1,000 for each day it was out of compliance with emission standards. MERC general manager Ken Robbins called the agreement fair.