Fracking isn’t used in San Luis Obispo County oil wells now, but it and other forms of well stimulation could be used here in the future.
Scientific studies, public records and comments made by industry representatives to trade publications show three key things about the drilling process that is used to increase oil and gas production:
- Fracking and other well stimulation treatments have been used in California for decades to increase well production.
- Fracking in California is different than in other places in the country, and therefore the environmental impacts are different.
- The use of fracking could expand in the Monterey Shale Formation — which stretches deep below the surface of much of California, including San Luis Obispo County — but its effectiveness in producing commercially-viable oil is uncertain.
The issue has come up as San Luis Obispo County residents consider how to vote on Measure G, which, if passed in November, would prohibit all new oil wells and well stimulation treatments including fracking in unincorporated areas of the county.
The No on Measure G campaign funded by oil companies has said that a ban on fracking is deceptive. Proponents say the measure would prevent fracking from ever happening.
Matt Cunningham, a paid spokesman for the No on Measure G campaign, said “There is no fracking in San Luis Obispo County. The geology of San Luis Obispo County doesn’t lend itself to fracking.”
Charles Varni, a spokesman for the Yes on Measure G campaign, agreed there is currently no fracking in the county and added, “we want to keep it that way. Once fracking starts, it is almost impossible to stop it and the negative impacts to groundwater quality and quantity.”
Fracking in California
What is fracking?
Hydraulic fracturing — commonly called fracking — sends a combination of water, chemicals and sand at high pressure deep into the earth until the surrounding rock breaks, causing fractures. The technology has often increased production by three to five times and is responsible for a natural gas boom from production in shale in Pennsylvania, North Dakota, Texas and other states.
However, people are concerned about intensive water use and pollution by chemicals said to be dangerous — potential impacts that the industry disputes.
An independent scientific assessment of the practice in California led by the California Council on Science and Technology resulted in a thorough peer-reviewed report in 2015. Here is what that committee of experts on oil and gas production, environment, water and geology found:
Where is fracking used in California?
Nearly all fracking operations in California are in the southwestern part of the San Joaquin Basin, specifically in oil fields in Kern County just to the east of San Luis Obispo County. It is generally used to extract more oil from fields where production has declined. From 2004 to 2014, one-fifth of oil and gas production in California came from wells stimulated with fracking.
Where will fracking likely be used in the future?
Future use of fracking will likely expand production in and near oil fields in the San Joaquin Basin that currently use fracking.
It could also be used to help produce oil from deep source rocks in the Monterey Formation. Producing oil resources from that shale formation will require innovative technology, likely including fracking. However, it is likely that future production will come from reservoirs with oil that migrated from the source rocks.
Parts of the Monterey Shale Formation underlay San Luis Obispo County in North County near Lake Nacimiento and in the southeast corner of the county near the Carrizo Plain. The formation underlays the Cuyama and Salinas basins that include portions within the county.
Is fracking in California the same as fracking in other regions?
No. Fracking in other regions is used to produce natural gas in horizontal wells more than 10,000 feet below ground. In California, current fracking tends to be used to produce oil in shallower, vertical wells at depths less than 2,000 feet below ground, because the geology is different.
How are the environmental issues different?
Shallow fracking in California tends to use less water per operation than in other regions — 140,000 gallons in California compared to 4.3 million gallons per well in the Eagle Ford Shale in Texas — but uses fluids with more concentrated chemicals than in other states.
There is a risk that fractures could accidentally contaminate drinking water aquifers above the operations.
What about acidizing?
Matrix acidizing is another well-stimulation practice used in California, but much less frequently than fracking, data show. The process involves injecting an acid solution at lower pressure into a formation to dissolve rock or other materials. Operators regularly use acid treatments for well maintenance. Acid stimulation is not considered useful now or in the future to increase oil and gas production because of the underlying geology of California.
Hopes for Monterey Shale Formation
Projections about a potential of 13.7 billion barrels recoverable oil in the Monterey Shale deposits led to talks about a new oil boom in California just a decade ago.
That changed with the U.S. Energy Information Administration slashed the estimates by 96 percent in 2014. Experts admit that the real amount of recoverable oil from the formation is unknown.
The Monterey Shale Formation causes a challenge to operators because of the geology. The layers of underground rock and oil are folded, as opposed to flat layers like in natural gas fields in Texas.
Still, some companies see potential, including the California Resources Corp., which has a goal of accelerating oil production in California, including unconventional sources, according to Natural Gas Intel’s Shale Daily.
While California’s oil production has declined over the decades, some industry leaders have said that it has growth potential, according to Oil and Gas Investor.