Geology and unconventional oil extraction

Most of us use all manner of petroleum products. I am grateful for the opportunities and materials provided by petroleum.

At the same time, I want to preserve our water quality and avoid the irreversible hazards that would result from contaminated water escaping from deep rock formations into the groundwater.

During intensive oil removal processes, steam or water mixed with chemicals and sand are injected deep into the ground under high pressure.

Both Santa Barbara County Action Network and the local chapter of the Sierra Club support a reasonable and safe increase of already approved oil extraction, to generate tax revenues and increase the volume of cash flow to well-paid workers and into the local economy.

Favoring caution and restraint, however, both organizations support the initiative to ban fracking, which is to be decided by the voters in the November election.

Bear in mind the initiative does not interfere with current and already approved future oil-production projects and related employment incomes.

The local geology makes intensive oil extraction techniques risky. To better understand the hazards, I refer to sections of John McPhee’s book, "Annals of the Former World," for a geologist’s description of the rock strata under our feet on the Central Coast. They are not neatly horizontal, but are tortuously bent, folded, rotated and faulted due to very active plate tectonics.

Neat, horizontal layers might serve to confine injected materials. However, given the geological layer orientations that result from plate tectonics, injected steam, liquids or solids may sometimes not travel in the directions intended. In turn, oil, gas and produced water — possibly laden with toxic substances — might also follow unintended paths along faults or in geological layers leading upward, sideways or along continuous paths for long distances.

Although McPhee makes no reference to oil extraction, it follows that numerous flow paths permitting escape of toxic materials from the depths to near the surface are to be expected if enhanced pressurized injection is widely used. This could push toxic materials into groundwater situated hundreds of feet above the oil being extracted.

In fact, we recently saw cyclic steam extraction cause an increase in seeps, or "surface expressions," in an oil field south of Orcutt, where 96 wells were drilled using this technique. According to an article in the Santa Maria Times on March 8, seeps always occurred naturally at the site, but the number of them increased as the cyclic steaming project came on line. No one knows what route the oil took to reach the surface.

The oil company gained emergency permission to place seep cans to contain the oil. They then got permission to drill another 96 wells to attempt to alleviate the hazard they had exacerbated.

North County proponents of cyclic steaming argue that the oil being produced lies far below the groundwater we use for farming and urban uses. But even the slightest risk is too much, and because of the geology of the area, there is some risk.

If our aquifer is contaminated, it would be the ruin of Santa Maria Valley’s livability and agricultural productivity. Since these intensive extraction methods put our water at risk, we want to see these methods banned now to avoid damage that cannot be undone if failures occur in spite of the best efforts of the oil and gas producers.

Let’s continue a moderate level of oil extraction, but without fracking, cyclic steaming or related methods.

Jerry Connor is North County vice president of the board of directors of Santa Barbara County Action Network (SB CAN). He can be reached at jerry@sbcan.org. Looking Forward runs every Friday in the Santa Maria Times, providing a progressive viewpoint on local issues.

http://santamariatimes.com/news/opinion/editorial/commentary/geology-and-unconventional-oil-extraction/article_4635f667-8ec7-5cf6-91cf-7f27759d6e06.html

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Santa Barbara County Action Network
Santa Barbara County Action Network (SBCAN) works to promote social and economic justice, to preserve our environmental and agricultural resources, and to create sustainable communities.