The California Air Resources Board (CARB) has fined two solid waste collection companies: Redwood Debris Box Service Inc. of Burlingame, Calif., and Mountainside Disposal Inc./Price Disposal Inc. of Bakersfield, Calif., for violating air quality regulations related to diesel trucks they operate, CARB said.

Redwood Debris Box Service agreed to pay $39,250 for violating the regulations. Mountainside Disposal/Price Disposal paid its final payment of $38,625 in June for its violations. As part of the settlement, Mountainside Disposal also must ensure that staff members who are responsible for compliance with the diesel truck emission inspection program attend diesel education courses and provide certificates of completion within one year, CARB said.

Separate investigations by CARB showed each company failed to install legally required diesel particulate filters, which reduce harmful emissions, on its trucks by applicable compliance dates. Each company also failed to properly self-inspect its diesel trucks to ensure they met state smoke emission standards, CARB said.

Seventy-five percent of each fine, or a combined $58,405.75, will go to the California Air Pollution Control Fund, which provides funding for projects and research to improve the state’s air quality, CARB said. The rest will go to Peralta Colleges Foundation to fund emission education classes conducted by participating California community colleges under the California Council for Diesel Education and Technology program.

According to CARB, diesel exhaust contains a variety of harmful gases and over 40 other known cancer-causing compounds. In 1998, California identified diesel particulate matter as a toxic air contaminant based on its potential to cause cancer, premature death, and other health problems.