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Karen Garrison’s Blog

Can Nuclear Safety Be Improved Without Sacrificing Ocean Life?

Karen Garrison

Posted November 5, 2012

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I was just a child when scientists in St. Louis found radioactive material in thousands of baby teeth collected nationwide. People around the world were shocked to learn that fallout from nuclear testing had worked its way into the food chain, as dairy cows ingested radioactive material that landed on pastures. A test ban treaty is now in place, but decades later, we’re still living with the risks of nuclear power. The challenge is to reduce that risk in the safest and most effective way.

Right in our backyard, the Diablo Canyon nuclear power plant—near San Luis Obispo, California—has long caused concern because of its location between several active earthquake faults. As last year’s Fukushima nuclear disaster in Japan painfully reminded us, earthquakes and nuclear power plants can be a devastating mix, for both public health and ocean-dependent businesses.

Earthquakes pose a grave risk near the Diablo Canyon nuclear plant, with the closest fault—the Shoreline—running a mere 0.6 miles from the reactor. That’s why California energy agencies have recommended and PG&E has proposed the Central Coastal California Seismic Imaging Project (the project). Using high-intensity seismic surveys in ocean waters, PG&E intends to study faults and their connections deep under the seafloor near the plant.

No one disputes that nuclear safety should be a top priority. But in light of its impacts on marine life, the project raises serious questions about whether these survey techniques are absolutely necessary for ensuring the safety of the plant, and if so, whether less harmful alternatives are available.

As first proposed, the project would fire extremely loud air cannons in the water, causing significant impacts to vulnerable ocean creatures and ecosystems. The air guns would blast acoustic pulses of 230 to 250 decibels at the source every 15 to 20 seconds at all hours of the day for almost two months, over  393 square miles of ocean habitat. Just how loud is that? Imagine a jet taking off in your living room every 15 seconds, and multiply that by 100,000.

Point Buchon.jpg

Credit: Flickr / mikebaird

The resulting shock waves would particularly threaten the highly vulnerable Morro Bay harbor porpoise, and would also harm endangered blue, fin, and humpback whales and sea otters. The project would put sea birds, fish, squid, and other ocean life at risk, undermine the safeguards of Marine Protected Areas that local residents worked hard to create, and affect human communities that depend on thriving ocean life.

To my knowledge, a seismic survey of the contemplated duration and extent has never been conducted in such a rich and fragile nearshore habitat off California. PG&E has revised its project to phase it over several years, but it will still harm marine mammals, as well as sea life in Marine Protected Areas.

As for the need for the project, I have yet to find solid evidence it is necessary. Seismic surveys won’t, for example, answer the most influential questions for improving the hazard assessment at the plant—questions regarding the slip rates of the Hosgri, Shoreline, Los Osos and San Luis Bay faults, and whether the Los Osos fault angles toward the power plant, creating a higher risk.  Each of those questions can best be addressed by other types of studies that cause much less damage than offshore high-intensity surveys.

Fortunately, PG&E has just completed an array of other geophysical studies that focus on slip rates and other high priority uncertainties in the hazard assessment.  The revised project, by contrast, would address none of the top priority uncertainties. So the first step should be to integrate the results of other studies into the hazard assessment and take stock of whether questions critical to plant safety remain. If not, we will have avoided a great deal of damage to ocean creatures.

Are less harmful alternatives available if more information is needed?  An imaging technology called Marine Vibroseis that uses controlled vibrations rather than broad impulsive noise could reduce sound levels by orders of magnitude and substantially reduce risk for harbor porpoises and other species.  A non-acoustic technology called gravity gradiometry has reportedly allowed industrial clients to run fewer miles of airgun surveys by filling in gaps between tracklines.  Both warrant a close look.

Ensuring the safety of California’s nuclear plants is of the utmost importance. So is safeguarding endangered marine mammals and protected areas. At this point there is no need to choose between them because the case has not been made that the project is necessary to assure the safety of the plant or that it’s the least damaging option.

The Coastal Commission will consider PG&E’s permit application on November 14, 2012. Permitting agencies must take all necessary precautions to protect both our health and that of the fragile organisms in our oceans.  Given that less harmful studies likely will address high priority uncertainties in the hazard assessment, we urge the Coastal Commission to follow the staff recommendation and deny the permit.

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Susan HarnischNov 6 2012 07:03 PM

As a local resident, 20 mi from Diablo Canyon, where family has resided since 1924, I strongly appose further testing in order to permit this nuclear energy facility to go back online. 1) sonar/seismic testing will only prove it's on 13 dangerous faults, 2) testing is already known to destroy sea life for millenniums, 3) the effects of a nuclear accident would cause more world-wide devastation, 4) this proposal requires world-wide experts to look into it.

Francesca BologniniNov 8 2012 02:23 PM

As a person who originally opposed the concept of building a nuclear plant at the confluence of several faults, I see no safe way to operate such a facility. No existing test could possibly guarantee that a Fukushima sized event would not occur here. The only "safe" course of action is plant closure and clean up.

To conduct inconclusive tests in the name of "safety", tests whose only certain conclusions would be the locations of offshore oil deposits and in the process destroy an extremely valuable population of marine life, in all likelihood for well beyond my life time, is unconscionable . It seems extremely likely that we would be completely vulnerable to the prospect of off shore drilling, once our precious marine life was removed.

It is a sacred trust that we have to protect the well being of these creatures. This must be carried out vigilantly, in the face of fear mongering and greed, often at personal sacrifice and with a stout heart. I want to thank Ms. Garrison for her excellent piece, which spells out the inappropriateness to our "safety"of the proposed tests and their highly destructive nature.

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