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UST Program - Interim Regulations for UST Systems Storing Biodiesel Blends up to B20

UST Program – Interim Regulations for UST Systems Storing Biodiesel Blends up to B20

State Water Resources Control Board (State Water Board) regulations require that:

  • An Underground Storage Tank (UST) be approved by an independent testing organization;
  • An owner or operator use system components made of, or lined with, materials that are compatible with the hazardous substances stored in the UST;
  • The components approved for the installation of a UST system, on and after July 1, 2004, include a list of compatible products tested and the measured permeation rate of those products; and
  • The release detection equipment be tested by an independent testing laboratory and be approved to function with the substance stored.

With the exception of biodiesel blends up to 5 percent biodiesel (B5), USTs manufactured to date have not received independent testing organization approvals for biodiesel or other biodiesel blends. Further, leak detection methods/approvals have not yet been obtained for biodiesel or any blend of biodiesel.

These issues have contributed to the delay of more widespread use of biodiesel in California. Therefore effective June 1, 2009 emergency regulations are now in place which provide for a 36-month variance from the required independent organization certification of leak detection equipment with biodiesel and biodiesel compatibility with UST components. The interim provision specifically allows for UST systems to store biodiesel blends up to B20 in double-walled tanks, piping, and components that currently meet the operational permitting requirements for motor vehicle fuels (petroleum).

The documents listed below are excerpts from the complete rulemaking records, which is available for review upon request. Please direct questions on this regulation to Laura S. Fisher at lfisher@waterboards.ca.gov or (916) 341-5870.

Rulemaking Documents

Additional Resources