It all started when…

ExxonMobil’s history in Santa Barbara County dates back to 1968, when over the course of 14 years, the company consolidated more than a dozen offshore federal oil leases and organized them into a streamlined production unit known as Santa Ynez Unit (SYU). Today, SYU consists of three offshore platforms and an onshore processing facility located along the Gaviota Coast at Las Flores Canyon (LFC).  

SYU construction began in 1976 with Platform Hondo. Hondo began operating in 1981, producing oil for the domestic California market. In 1983, the Pacific Offshore Pipeline Company (POPCO) completed construction of gas processing facilities in LFC and began processing natural gas from Hondo for the local Santa Barbara County market. In 1987, Santa Barbara County Supervisors approved ExxonMobil’s permit to consolidate oil and gas processing in Las Flores Canyon and sanctioned oil transportation and sales via onshore pipeline. Construction in LFC began in 1989. Included in the onshore oil and gas treatment facilities were a network of pipelines, subsea power cables and communications links connecting the LFC facility and Platform Hondo with two new offshore platforms, Harmony and Heritage. In 1998, ExxonMobil purchased all the POPCO stock and the company remains an independent legal corporation. 

Initially production from Platform Hondo was processed aboard a large floating treatment and storage facility moored next to the platform in federal waters. Processed oil was then loaded onto oil tanker ships, which carried the oil to refineries in the Los Angeles market. Tanker operations continued until 1993 without incident. Since 1993, all SYU production has been processed at the Las Flores Canyon consolidated treatment facilities, enabling ExxonMobil to suspend its tanker operations. All of SYU’s oil production is now transported and sold via an onshore pipeline owned and operated by Plains All American Pipeline. This pipeline exclusively supplies California refineries with oil feedstock to make transportation fuels for the California market. The natural gas produced from the Santa Ynez Unit is purchased by local utilities and distributed directly to tri-county homes and businesses. Las Flores Canyon’s onshore facilities, visually hidden from the main roadway and coastline, as well as the three offshore platforms remained in continuous operation without incident until 2015. 

In May 2015, the Plains All American Pipeline that transported produced oil from ExxonMobil’s SYU, Venoco’s Platform Holly and Freeport MacMoRan’s Point Arguello Platforms experienced a leak. Production at all the ExxonMobil platforms and facilities was safely and temporarily suspended in June 2015. Subsequent efforts was initiated to place SYU into a preserved state. In 2016, Santa Barbara County Supervisors approved an emergency permit to de-inventory remaining produced oil stored at SYU. Oil transport by truck in 2016 from the Gaviota area to Santa Maria completed 2,500 deliveries and logged over 350,000 miles without an accident.

Since completion of de-inventory trucking operations, all SYU facilities and pipelines have been freed of hydrocarbons and fully preserved. SYU’s current preserved safe state requires ongoing inspection, maintenance and surveillance of all equipment. 

Description of facilities 

ExxonMobil’s Santa Ynez Unit (SYU) consists of three offshore platforms — Hondo, Heritage and Harmony — and an onshore oil and natural gas processing facility in Goleta, California. 

The platforms are located from five to nine miles offshore Santa Barbara County in federal waters. 

ExxonMobil owns and operates 16 federal leases. Subsea pipelines transport crude oil, natural gas and produced water from the platforms to the onshore processing facilities. 

Site history 

ExxonMobil and its predecessors have had a presence in the Santa Barbara region since the late 1960s. In 1970, the Santa Ynez Unit was formed, and production of crude oil and natural gas began in 1981. In 1993, the onshore oil treatment plant in Las Flores Canyon, along with the two additional platforms, Harmony and Heritage, started operations. 

In 2010, ExxonMobil’s advanced drilling technologies enabled the company to drill what was, at the time, the world’s longest extended-reach well from an existing offshore fixed platform drilling rig, increasing the company’s ability to produce more domestic oil supplies from existing facilities at SYU. The well, drilled from the Heritage platform, extends more than six miles horizontally and more than 7,000 feet below sea level. 

Production overview 

Between 1981 and 2014, SYU produced over 663 million oil equivalent barrels (oil and gas). Production was an average of 27 million cubic feet of natural gas and 30,000 barrels of oil and condensate per day (gross) in 2014. 

The processed crude oil was transported by pipeline to California refineries. Natural gas was sold for distribution to California homes and businesses.