Earlier this year, the oil company Plains Exploration and Production (PXP) blasted water and chemicals more than one and half miles into the earth to force oil embedded in a sandstone formation to gush to the surface.
The process—known as hydraulic fracturing or "fracking"—has been debated in many U.S. communities where oil and gas deposits have been identified in recent years. But PXP wasn't fracking in the much-touted Marcellus Shale on the East Coast, where much of the controversy over fracking has centered. It was fracking two test wells in urban Los Angeles, where 300,000 people live within a three-mile radius.
The drilling was done less than a year after community and environmental groups reached a settlement with PXP, after complaining for years about pollution from the site.
Hydraulic fracturing, which is used to recover deeply buried sources of gas and oil, is emerging as a contentious issue in California. Nearly two-thirds of the nation's shale oil deposits are found in California, according to the U.S. Energy Information Administration, but most of it is hard to recover without fracking.
A recent report in Los Angeles Times revealed that the state is ill-prepared for a surge in this type of drilling, with regulators as well as residents struggling simply to define fracking, much less pinpoint where it is occurring.
The escalation of fracking is of special concern to Californians, because the process uses vast quantities of water, one of the state's scarcest and most precious resources. The most controversial form of fracking—high-volume, horizontal hydraulic fracturing— can require millions of gallons of water to frack a single well. Fracking in vertical, or conventional, wells can use up to hundreds of thousands of gallons of water.
Both types of fracking also inject chemicals with the water, raising concerns about the possible contamination of drinking water sources. The state already has identified many hotspots where groundwater has been tainted with agricultural chemicals, such as nitrates.
Fracking Renews Interest in Old Oil Field
The wells that PXP recently fracked are located in the Inglewood Oil Field, which has been operating in Los Angeles since the 1920s. It sits at the southern tip of a massive geologic formation known as the Monterey Shale, which extends up through parts of the central coast and San Joaquin Valley.
Sprawled across 1,000 acres of land, the Inglewood Field is the nation's largest urban oil field. Its boundaries are lined with neighborhoods whose residents, more than two-thirds of them non-white, have been complaining about pollution from oil drilling for decades.
In 2006 a release of noxious gases at the Inglewood Field galvanized community members and environmental groups to sue Los Angeles County, to force it to augment protections the county had previously created in partnership with PXP. The parties reached a settlement last year that further limited PXP's oil drilling activities, including reducing the number of wells the company could drill.
Production at the wells had also been declining in recent years, and the community thought the field would eventually close and their problems would disappear. But rather than tamping down on oil drilling, residents recently learned that PXP, which bought the oil field from Chevron in the mid-1990s, may be eyeing the oil field's untapped shale oil, which had once been considered too expensive to extract.
As part of the settlement agreement, PXP agreed to conduct a study that examined the feasibility and impact of current and future fracking at the oil field. It would be the first study to look at the impact of fracking in California, including its impact on groundwater.
Damon Nagami is a staff attorney with the Natural Resources Defense Council, which was a party to the lawsuit. He said the community that surrounds the oil field didn't learn about the test fracking until March 9, after the fracking was complete.
The two vertical wells were fracked in September and January. PXP shot as much as 168,000 gallons of water laced with chemicals into one well to a depth of about one and half miles, according to information disclosed by the company on the website FracFocus.
PXP "didn't do a good job of informing people this was happening. They could have gotten input from broad segments of the community before they fracked the test wells," Nagami said. He thinks that a broader discussion could have explored alternatives, such as using data from similar fracking operations elsewhere.
The office of the Community Health Councils, a local nonprofit that also participated in the settlement negotiations, is a half mile from the oil field.
"The community's impression was that things were winding down. The oil field was reaching the end of its life span," said Mark Glassock, a community advocate with the group. Nearby residents are now more concerned than ever about risks the oil field could pose to their health and their drinking water.
Impact on Water Resources
PXP declined to comment for this story, saying the company is waiting for the results of its fracking study, which are due in July. Under terms of the settlement, PXP and the Los Angeles County Department of Regional Planning, which oversees the oil field, can jointly select an independent peer-reviewer to review the findings.
The planning department deferred technical questions about the study to its environmental consulting firm, Marine Research Specialists. John Peirson, a principal of the company, said the water used to frack the wells came from a natural underground reservoir that lies deep beneath the oil field. He said that water from the reservoir contains so much saline that it can’t be used for drinking.
But another layer of water lies above the reservoir, and it is the safety of that water that worries Samuel Unger, executive officer with the Regional Water Quality Control Board, Los Angeles Region. He said that the groundwater may be a "tributary" to other water basins that provide some of the drinking water used by residents in the central area of Los Angeles County.
"Our [water] board is concerned about potential impacts to groundwater from oil field activities including the recent hydraulic fracturing activities," Unger said.
Tony Kovscek, an expert on hydraulic fracturing at Stanford University's School of Earth Sciences, said the fracking at the Inglewood Field is occurring so far below the groundwater basin that it's "unlikely the fracture will interact with groundwater." The key to keeping the process safe, Kovscek said, is making sure the wells are properly constructed and that the cement seal is intact.
"If that isn't done very well, that's when you get the potential for contamination," he said, noting that the 2010 BP oil leak in the Gulf of Mexico [the Macondo blowout] resulted from a cementing problem.
"The industry knows what to do to ensure it [a leak] doesn't happen," Kovscek said. "Do they do the test they are supposed to do and be vigilant?"
The California legislature is beginning to address some of the challenges presented by hydraulic fracturing.
Assembly Bill 591, authored by Assemblyman Bob Wieckowski (D-Fremont), would require that California producers register the chemicals they use in hydraulic fracturing projects on a public website and that state regulators identify which wells have been hydraulically fractured on its website.
A "notification" bill that is currently moving through the California Senate would also require energy companies to notify property owners before drilling or fracking occurs near their land. SB 1054, authored by state Sen. Fran Pavley (D-Agoura Hills), passed the Senate Natural Resources Committee on Tuesday.
This story was reported and written by Ngoc Nguyen at New America Media in collaboration with editors at InsideClimate News.