16 USA nuclear power plants vulnerable to flooding from dam failure

List of Reactors Potentially at High Risk of Flooding due to Dam Failure

Alabama: Browns Ferry, Units 1, 2, 3

Arkansas: Arkansas Nuclear, Units 1, 2

Louisiana: Waterford, Unit 3

Minnesota: Prairie Island, Units 1, 2

Nebraska: Cooper; Fort Calhoun

New Jersey: Hope Creek, Unit 1; Salem, Units 1, 2

New York: Indian Point, Units 2, 3

North Carolina: McGuire, Units 1, 2

Pennsylvania: Beaver Valley, Units 1, 2; Peach Bottom, Units 2, 3;

Three Mile Island, Unit 1

Tennessee: Sequoyah, Unit 1; Watts Bar, Unit 1

Texas: South Texas, Units 1, 2

South Carolina: H.B. Robinson, Unit 2; Oconee, Units 1, 2, 3

Vermont: Vermont Yankee

Virginia: Surrey, Units 1, 2

Washington: Columbia

(Source: Perkins, et al., “Screening Analysis,” July 2011) http://www.nationofchange.org/whistleblower-nuclear-regulators-suppress-facts-break-law-1354009225

Whistleblower: Nuclear Regulators Suppress Facts, Break Law, Nation of Change, William Boardman, 27 November “…….Event Unlikely, Would Be Sure Disaster South Carolina’s Oconee plant on Lake Keowee has three reactors, located 11 miles downstream from the Jocassee Reservoir, an 8,000 acre lake. As HuffPo put it:

…the Oconee facility, which is operated by Duke Energy, would suffer almost certain core damage if the Jocassee dam were to fail. And the odds of it failing sometime over the next 20 years, the engineer said, are far greater than the odds of a freak tsunami taking out the defenses of a nuclear plant in Japan….

“Although it is not a given that Jocassee Dam will fail in the next 20 years,” the engineer added, “it is a given that if it does fail, the three reactor plants will melt down and release their radionuclides into the environment.”

When the NRC granted an operating license to the Oconee plant in 1973, danger from upstream dam failure was not even considered, never mind considered a threat against which some protection was needed. The NRC and the plant’s owner both say the Jocassee Dam is not an immediate safety issue. Oconee’s initial license was for 40 years. It is now the second plant in the U.S. that the NRC has granted an extended license for another 20 years.

Union of Concerned Scientists Are Concerned

The Union of Concerned Scientists, which says it is neither pro-nuke nor anti-nuke, but committed to making nuclear power as safe as possible, has considered the risk factors for Oconee. The NRC wrote in 2009 that “a Jocassee Dam failure is a credible event and in 2011 wrote that “dam failures are common” – and that since 1975 there have been more than 700 dam failures, 148 of them large dams 40 feet or more high. The Jocassee Dam is 385 feet high.

For a dam like Jocassee, the NRC calculates the chance of failure at 1 in 3,600 per year – or 1 in 180 each year for the extended license. NRC policy, when enforced, requires nuclear plant owners to mitigate any riskthat has a 1 in 250 per years chance of occurring.

Oconee has three nuclear reactors, each of which is larger than the reactors at Fukushima, and so has more lethal radioactive potential. Duke Energy reported its own upstream dam failure calculations to the NRC no later than 1996 and the NRC has responded by requiring no safety enhancements to address the threat.

Noting that the upstream dam failure risk does not take into account possible earthquakes or terrorist attacks, the Union of Concerned Scientists wrote:

The 34 reactors of concern are downstream from a total of more than 50 dams, more than half of which are roughly the size of the Jocassee dam. Assuming the NRC’s failure rate applies to all of those dams, the probability that one will fail in the next 40 years is roughly 25 percent—a 1 in 4 chance.