State Board Petitions




State Board Petition, Boyes Hot Springs, CA


Major Oil Company


The gasoline service station was divested by the oil company in 1991 and a new independent owner purchased the property and service station improvements.  The independent service station owner has operated a non‑branded service station from 1991 to the present.  The oil company had a previous petroleum hydrocarbon release they are responsible for and were performing assessment and routine groundwater monitoring and reporting work tasks.  Monitoring data for on-site wells near and downgradient of the site’s underground storage tanks (USTs) showed evidence of two methyl tertiary butyl ether (MTBE) releases from the independent service station owner’s tanks in 2001 and 2003.  Despite multiple meetings with the County Environmental Health Department (County), the preparation of a site conceptual model per the County’s request that clearly documented at lease two post-property divestment MTBE releases had occurred, and the County’s change of position from MTBE releases did occur to they did not occur on two occasions, the independent service station owner was not named a responsible party.


Prepare a formal petition to the State Water Resources Control Board (State Board) to name the independent service station owner as responsible party for the post-divestment MTBE releases that occurred at the site.


Trinity’s assertion of a second release at the site was based on two lines of evidence.
The first line of evidence was based on concentration trends for total petroleum hydrocarbons as gasoline (TPHg), benzene, MTBE and tert-butyl alcohol (TBA).  While TPHg and benzene concentration trends in site wells were decreasing, MTBE and TBA trends were increasing.  These trends suggested one or more releases involving MTBE and possibly TBA.  The second line of evidence was UST system leak test records, indicating failed tests in 2002 and 2004.  Trinity prepared a Petition to State Water Resources Control Board for Review of Action todemonstrate a second release occurred at the site.


  • The State Board adopted an Order based on their review of the Petition stating that there was reasonable and credible evidence that indicated there was a release of vapor-phase gasoline from the USTs that are currently located at the site.  Further, the State Board concluded that the independent property service station owner and operator should be added as a primary responsible party for the unauthorized release at the subject site.
  • The project is ongoing and following completion of an additional on‑ and off‑site soil and groundwater investigation the major oil company will hand over full environmental cleanup responsibility to the independent property owner and service station owner/operator.  The station owner intends to file a claim with the UST Fund for reimbursement of cleanup costs.