of the Guadalupe Restoration Project
Late 1940s The first commercial oil well was
drilled at Guadalupe.
Unocal purchased 51 percent interest in the Guadalupe
A refined petroleum hydrocarbon, referred to as "diluent"
(diesel/kerosene mix) was introduced at the site to assist
in thinning the crude to facilitate production and transportation
of the heavy crude oil. The diluent was transported to the
site by pipeline and truck and distributed within the oil
field by a system of storage tanks and pipelines.
March 1953 The site produced up to 2,000 barrels
per day from 34 oil wells.
June 1953 Unocal purchased the remaining interest
and became the operator.
1988 Expansion of the oil field has resulted in
up to 215 potential producing wells, with a peak production
of approximately 4,500 barrels per day. Unocal makes its first
report to state officials when employees note a petroleum
smell on the beach next to the Guadalupe Oil Field. The source
of the problem isn't determined, and the oil disappears from
the water in a few days.
1990 Unocal reported oil on the beach, shut down
field operations and permanently discontinued use of diluent.
For a short period of time, a segment of the field was put
back on production using warm water - not diluent - to make
1994 - February 1995 Under order from the U.S.
Coast Guard, Unocal conducted excavation activities at the
5X site. The County of San Luis Obispo issued Permit SLO P890275E
(Modifications #4 and #5) for the 5X Excavation Support Facilities.
Approximately 136,000 cubic yards of affected material was
excavated and treated using thermal desorption units (TDUs).
A total of ten extraction wells were installed on the upstream
side of the excavation area to collect diluent approaching
the excavation site. A total of about 250,000 gallons of diluent
was removed from the excavation area.
Spring and summer of 1995 The Santa Maria River
changed course and migrated north. Unocal, concerned that
the migration might continue and inundate the HDPE wall, developed
a plan to install sheet pile at the southwest corner of the
HDPE wall. A former production sump at the LeRoy Well #2 was
exposed approximately 800 feet south of the 5X HDPE wall.
March 26, 1998 County of San Luis Obispo certified
the Final Environmental Impact Report.
3, 1998 RWQCB issued Cleanup or Abatement Order
No. 98-38, for the Unocal Guadalupe Oil Field, outlining remediation
requirements for Phase 1.
May 15, 1998 Unocal submitted to the RWQCB an
Implementation Plan for the remedial actions mandated by Cleanup
or Abatement Order 98-38.
1998 Unocal reached a settlement of a civil suit
with the State of California stemming from diluent releases
at the Guadalupe Oil Field. The $43.8 million settlement includes
funding for restoration, replacement and rehabilitation efforts
involving natural resources at the Guadalupe Oil Field.
August 13, 1998 County Planning Commission approved
Unocal's permit application for the project.
22, 1998 The San Luis Obispo County Board of Supervisors
approved Coastal Development Permit/Development Plan D890558D
for the Unocal Guadalupe Oil Field Remediation Project with
6, 1998 RWQCB issued a revised Cleanup or Abatement
10, 1998 San Luis Obispo County Planning Commission
approved CDP/DP D890558D, which had been revised by County
Planning Staff in conjunction with the Coastal Commission
12, 1999 Unocal contributed $285,000 to the Guadalupe
Dunes Center, and $784,000 to Rancho Guadalupe Park as part
of the company's mitigation requirements to begin Phase I
work at the site.
20, 1999 Three recovery systems at the Compressor
Plant, Tank Battery 9, and Diluent Tanks areas and a biosparge
system at the Tank Battery 8 area were placed in full-time
2001 All beach excavations were completed, a landmark
event for the Guadalupe Restoration Project, which involved
over 10 years of planning, permitting, and implementation.
September 2001 - Twelve additional excavations were completed, bringing the total of removed hydrocarbons to over two million (2,000,000) gallons.
October 2001 - Excavations were halted while Unocal prepared plans for 8 possible alternative methods of treatment and/or disposal of the growing stockpiles of excavated material and submitted them in a Supplemental EIR (SEIR) to be evaluated by the agencies.
December 2001 - Removal of approximately 145 miles of
abandoned pipelines from the former Guadalupe Oil Field that
were used for transporting oil, natural gas, water and steam was completed.
May 2002 - Unocal began construction of the Hot Water Flooding/Steam Injection Pilot Test. Numerous delays caused the actual test to be postponed until october 2003. The injection phase of the test was completed in April 2004, and was followed by post-steam monitoring and biosparge activities. The test site was fully decommissioned in August 2004. Final reports on the Steam Pilot Test were ratified in December 2005.
2002 Unocal purchases the Guadalupe Oil Field,
consistent with its commitments to provide a site-wide conservation
easement that will assure permanent preservation of the unique
coastal dune ecosystem.
March 2004 - The "Site-Wide Screening Level Ecological Risk Assessment" was ratified and a brochure was published for public distribution.
September 2004 - Unocal donated $100,000.00 to the Dunes Center in the town of Guadalupe toward construction of its new Visitor Center.
September 2004 - Unocal filed Irrevocable Offers to Dedicate, granting Conservation and Open Space Easements to the US Fish and Wildlife Service for the property's inclusion into the Guadalupe-Nipomo Dunes Complex. Unocal will provide habitat management support for 25 years following acceptance of the easements.
July 2005 - The San Luis Obispo County Planning Commission approved the Supplemental EIR (SEIR). In conjunction with approval of the Santa Maria Landfill's SEIR incorporating the trucking of Non-Hazardous Impacted Soil (NHIS) for use as capping material for closed landfill cells, off-site trucking of stockpiled and future excavated NHIS was determined the most appropriate method of disposal for the Guadalupe Restoration Project.
July 2005 - Requests for Proposal were distributed to 6 contractors for bids on off-site trucking and the remaining Phase I excavations. The contract was awarded to RECON in December 2005.
June 2006 - The California Coastal Commission ruled against an appeal brought by a group of Santa Maria residents in an attempt to halt trucking through the city.
August 2006 - Trucking operations began for the transfer of NHIS to the Santa Maria Landfill.