Local Oversight Program
Underground Storage Tank Clean-Up
Under contract with the State Water Resources Control Board (SWRCB), the Riverside
County Department of Environmental Health, Local Oversight Program (LOP) oversees the investigation
and cleanup of soil and groundwater contamination resulting from unauthorized releases of petroleum
products (gasoline, diesel fuel, waste oil, etc.) from leaking underground storage tanks
(USTs). The cleanup of these sites is necessary to protect the groundwaters of the State from
contamination and to protect the public from exposure to hazardous materials.
Reporting A Leak or Spill from an Underground Storage Tank
Owners and operators of underground storage tanks (USTs), as well as property
owners, have responsibilities under federal and state laws when an unauthorized release of
petroleum products (gasoline, diesel fuel, waste oil, etc.) from an underground storage tank (UST)
is discovered. These persons, or “Responsible Parties,” must report all unauthorized releases
to the Department of Environmental Health within 24 hours of the discovery of the release, spill,
or overfill from an UST, and must take any needed corrective action to stop the release and prevent
further impact to the environment. A written report documenting the release along with
an
Unauthorized Release Report
must be provided to the Department within 5 days of the release. Contamination
resulting from an unauthorized release must be adequately assessed and mitigated.
Investigation and Cleanup of Contamination from Underground Storage Tanks
When a release is reported to the Department, the site is entered into the Riverside
County Local Oversight Program (LOP) for oversight of the investigation and cleanup of
contamination. Responsible parties are required by law to take corrective actions to assess
and mitigate soil and groundwater contamination resulting from an unauthorized
release.
During each phase of assessment and cleanup, technical workplans and reports are
required to be submitted to and accepted by the LOP. Guidelines for implementing corrective
actions and preparing related documents in Riverside County are available to assist responsible
parties and consultants.
Click here to view the Riverside County Corrective Action Guidelines
. Responsible parties and consultants should refer to this document prior to
submitting technical documents or conducting any field activities in Riverside County.
Once assessment and cleanup efforts have been successfully completed, the Riverside
County LOP will issue a closure/no further action letter to the responsible parties. Should
there be changes in site usage or if additional contamination is discovered, the property owner
must contact the Department for an evaluation of the site. Based on the proposed use of the
site or extent of the newly identified contamination, the Department will determine if any further
action is required to protect public health or the environment.
Site Information, Public Notices and Landowner Notifications
Information regarding UST cleanup sites and proposed corrective actions at these
sites is available online. Click here to go to
public notices
. Responsible parties must notify all landowners of planned corrective actions
and prior to closure of the cleanup site. Click here for further
Landowner Notification
information.
Staff Assistance
Corrective actions at UST cleanup sites are overseen by LOP staff. Each site is assigned to a caseworker who will provide consultation and technical assistance to the responsible parties. Responsible parties are encouraged to contact the caseworker assigned to their case for assistance regarding all aspects of site cleanup. Go to our office locations page to contact the Local Oversight Program.