California to allow underground storage of up to B20 blends

In California, the state has cleared the way for storing biodiesel blends of up to 20 percent (B20) in underground storage tanks, removing the last major barrier to satisfying the state’s thirst for biodiesel.

Through an effort lasting more than 10 years, the National Biodiesel Board, several member companies, and the California Advanced Biofuels Alliance provided the State Water Board with data necessary to demonstrate B20 compatibility in underground storage tanks.

The vast majority of diesel fuel is stored in underground storage tanks, particularly at retail fueling locations. Although biodiesel biodegrades in water as fast as sugar, regulators had concerns that any degradation of UST materials could allow diesel fuel to compromise the water supply.

The California State Water Resources Control Board amended California Underground Storage Tank (UST) Regulations on August 6. The regulations now say that diesel containing up to B20, meeting the ASTM standard for B20 (D7467), “shall be recognized as equivalent to diesel for the purpose of complying with existing approval requirements for double-walled USTs, unless any material or component of the UST system has been determined to not be compatible with B20.”

The language reverses the previous wording of the regulation, which in effect required tank owners to prove that every component of the tank was compatible.