Skip to content
Ralph Nader > In the Public Interest > Nuclear Earthquake

The first move the electric company that owns the Diablo Canyon plant in southern California took on hearing that an earthquake had struck the San Francisco bay area over 500 miles to the north was to shut the plant down. The reason: Diablo Canyon is an atomic energy facility.

It is remarkable how little attention the press has given to a recipe for disaster that is a combination of nuclear power plants and earthquakes. Yet, as colleague Ken Bossong of the Critical Mass Energy Project in ‘Washington. D.C. observed: “Numerous U.S. nuclear reactors such as Diablo Canyon in California, Indian Point in New York, and Millstone in Connecticut are constructed perilously close to known fault lines.”

Bossong’s points are so compelling that they are reported verbatim:

“Following an earthquake, a crack in the piping which carries cooling water to the reactor core could result in a rapid loss of coolant. Within minutes thereafter, the fuel rods in the core could melt leading to an explosion. Radioactive materials would almost certainly leak from the reactor under any circumstance and particularly if an explosion breached the reactors containment dome. According to government studies, a major nuclear accident of this sort could result in thousands of immediate, deaths as well as billions of dollars in property damage.

The nuclear industry maintains that nuclear reactors have been designed to Withstand earthquakes. However, this assumption is based on computer modeling which has been found to be faulty in the past. For example in 1979, the U.S. Nuclear Regulatory Commission (NRC) temporarily closed five nuclear reactors when it discovered that engineers had underestimated the stresses that piping in the reactors’ coolant systems might have to withstand in the event of an earthquake. Other nuclear plants, such as the Humboldt Bay reactor in northern California, have been closed after years of operating because they were belatedly found incapable of withstanding a severe, earthquake.

“The safety of nuclear reactors also presumes that individual components (e.g. piping, valves, electrical circuitry) have been specially engineered to certain seismic specifications. Yet, in the past year, the NRC has acknowledged that counterfeit and substandard parts have been widely used in the construction and maintenance of the nation’s nuclear reactors.

“Whether any nuclear reactor could withstand a quake that registers as high as 7.5 on the Richter scale is purely hypothetical since the nuclear industry has no experience with a quake of that magnitude. As was true for the ramp of Freeway MO which collapsed in San Francisco following a 6.9 quake, the seismic design systems of these plants could prove deficient in the event of a major earthquake.

“Yet, a 7.5 quake is not only very possible in California, the home of six commercial reactors, but also in the eastern United States where most nuclear plants are located and which experienced two of the strongest earthquakes in U.S. history in the 1800`s.

“Of at least equal concern are the radioactive waste storage pools located on the sites of most nuclear power plants. Since the waste stored in these pools can contain even more radioactivity than found in the reactors themselves, they pose an even greater risk of a catastrophic accident in the event of an earthquake. And, arguably, since these pools were originally designed as temporary structures, the construction of these pools vis-à-vis seismic criteria is more lax than for the reactors themselves.

“Likewise, the nuclear weapons production reactors operated by the U.S. Department of Energy pose an even greater safety threat since they are not required to meet the minimum seismic requirements established for commercial nuclear power plants by the NRC. For example, the Savannah River nuclear complex is situated 90 miles from Charleston, S.C. which experienced an 8.0 quake in 1886.

“Finally, the emergency evacuation plans developed for each nuclear plant largely discount the possibility of an earthquake. Nationwide, these plans assume that all persons within 10 miles of a plant (on average, about 6Q000 people) can be evacuated within an average of 5.1 hours. The evacuation plan for the Diablo Canyon plant, south of the area impacted in the quake, assumes this can be accomplished in 4.3 hours.

“However, it took hours to clear Candlestick. Park alone following yesterday’s earthquake. Likewise, the chaos caused by damaged roadways, overworked and impaired communications systems, and loss of electrical power graphically illustrate how absurd these nuclear plant evacuation plans are.

“A major nuclear accident following an earthquake is more likely a matter of time than merely a remote possibility. In light of this and other arguments, a strong case can be made for rapidly phasing out the use of nuclear power in the United States. For the moment, though, federal regulators should at least view yesterday’s earthquake as a final warning that seismic: standards and testing for all nuclear reactors as well as evacuation planning needs to be substantially upgraded before the next quake hits.”