State regulators have taken the rare step of placing an entire oil field under technical scrutiny following continued, uncontrolled releases of oily fluid at Chevron Corp. operations near McKittrick.
California's Division of Oil, Gas and Geothermal Resources said it is "exploring swift next steps" to investigate fluid releases at the Cymric Oil Field. The evaluation will be done with the help of scientists at the prestigious Lawrence Livermore and Lawrence Berkeley national laboratories in the Bay Area, DOGGR said.
The study was announced along with DOGGR's disclosures late last week that it has issued two notices of violation against San Ramon-based Chevron, which operates wells in Cymric that have recently been linked to "surface expressions," in which oil and water have flowed up from the ground and pooled on the surface.
Surface expressions have occurred repeatedly in Kern County but are now against state law under regulations that took effect April 1. State officials say none of the recent leaks have threatened drinking water, harmed humans or damaged the environment.
A DOGGR spokeswoman on Tuesday termed the division's move to study the entire Cymric field "unusual," saying it is intended to help the agency gather information about recent surface expressions.
A violation notice DOGGR sent Chevron Friday relates to a surface expression that has continued to release oily fluid at varying rates since 2003. It is located about 1,050 feet from the site of a large, high-profile leak that began in mid-May and has since released some 31,903 barrels (more than 1.3 million gallons) of oil and water through Aug. 20.
The notice said flow from the older leak has shot up from a daily average of 250 barrels (10,500 gallons) to 10 times that rate earlier this month. Chevron continues to contain and remove the fluid, which it has said is between 60 percent and 80 percent oil.
Terms of the notice call for Chevron to prove that a nearby steam- and oil-production project is confining injections to the intended zone underground. The company must also produce detailed paperwork on all wells within 1,200 feet of the site, share plans for new well-testing and turn over 10 years' worth of injection and production data on all wells within the 1,200-foot radius.
The other violation notice, filed Saturday, regards a much smaller surface expression that began Wednesday at a site 1,800 feet from the leak that started in mid-May.
The order instructs Chevron to give DOGGR an analysis showing why the leak occurred and what tests have been run there, as well as a list of what the company is doing to prevent future surface expressions.
The notice also requires Chevron to stop steam injections within at least 300 feet of the leak, and if the releases continue, to increase the radius to 600 feet or more.
Chevron emphasized in an email that the surface expressions have injured no one and have had no impact on groundwater, surface water, wildlife or agriculture. It also stressed that the leaks are contained, that the company reported them to the appropriate regulating agencies and that Chevron is working to manage the incidents.
At the smaller leak discovered last week, Chevron said, about 940 barrels (39,480 gallons) of oily fluid have come to the surface. It suggested that some blame may lie with the closure of nearby wells and halt of steam injections, all of which were done to stop the leak that first appeared in mid-May.
"These activities are thought to be redirecting energy in the reservoir, which could be a contributing factor to this new seep," the company said by email.
Chevron said the much older surface expression referred to in the other violation notice has brought up roughly 2 million barrels (84 million gallons) of fluid, all of which it said is collected and either pumped into a pipeline or removed with a vacuum truck. It added that the company is cooperating with regulators and conducting a thorough review to determine next steps.
"Over the years," the company stated, "the appropriate regulatory agencies have been consulted regarding the seep and have been involved at all steps of the processing and handling of (the surface expression's) fluids."