An earthquake of sufficient destructiveness to take down the electrical grid as well as destroy vulnerable access points to the plant on the adjacent Interstate 5 could, however, cut SONGS electric supply. If the water in the spent fuel pools ceases to be circulated by the pools’ electrical systems, the increasingly hot water will evaporate off and the rods will alight in a 900 degrees Celsius (1,173 degrees Kelvin) nuclear fire that cannot be extinguished with any amount of fresh or salt water.
SCE has failed to implement expensive but more secure “dry casking” of spent nuclear fuel rods. The company says that fuel assemblies should stay in the pools for 7 to 10 years to cool down enough to be put in the sealed casks that cost $1 million each. So instead of dry casking rods years past being ready for it – SONGS opened in 1968 – SCE has kept loading more fuel rods into pools designed for fewer of them. According to the NRC, fuel rod assemblies can be transferred to dry casking within five years of being removed from the reactor.
“Only 25% of San Onofre’s highly toxic spent fuel is stored in dry casks,” PSR-LA said addressing the threat. “The remaining fuel is stored in pools, which remain vulnerable to earthquakes and power failure. If exposed, the fuel can self-ignite and release vast amounts of lethal radiation.”
That means that SCE, which has a 78.1 percent stake in SONGS and a $2.7 billion fund to completely cleanup and decontaminate the complex, hasn’t fortified its intensely radioactive rods that have to be kept out of the environment for up to a million years. The company says it needs $300 million to complete the fund. SCE is not alone in this venture, as San Diego Gas & Electric owns 20 percent of SONGS and 1.79 percent is owned by the city of Riverside.
“The high level waste–the spent fuel rods–has no place to be disposed of at present and will have to be put into dry cask storage on site for an extended period,” Hirsch said. Hirsch has analyzed the vulnerability of the spent fuel pools for decades and suggests that the dry casks be housed in hardened accessible bunkers with low profiles to protect against any number of terrorism scenarios.
It is a recommendation that has added urgency since the Friends of the Earth study was released. Called Reducing the Hazards of High‐Level Radioactive Waste in Southern California: Storage of Spent Power Reactor Fuel at The San Onofre Nuclear Station, [2.29 MB] the report revealed sourced information that 73 percent of the spent nuclear fuel at SONGS still sits in the two pools adjacent Units 1 and 2.
Cesium-137 makes up about 43 percent of the medium and long-lived radioactivity in the spent fuel, 168 million curies of which are in the pools. That amount of Cs-137, with a half-life of 30.2 years, is six times more than was released by all above-ground nuclear weapons testing and nearly 89 times the amount released by the Chernobyl nuclear meltdown in Belorussia in 1986.
The FOE report cited an NRC 2007 report emergency planning and response exercise in an imagined scenario of an earthquake at San Onofre severe enough that it cracks a pool which drains and catches fire. The NRC postulated that six hours after the spent fuel pools water drained, the exposed rods would catch alight sending about 40 million curies of cesium into the air.
“This is 150 percent more than released by all atmospheric nuclear weapons tests,” the FOE report says. “The resulting doses to people living within a 10‐mile radius would be in the lethal range.”
The fallout from such a spent fuel pool fire would impact Southern California far more than the Fukushima nuclear disaster initially impacted Japan. Around 80 percent of the March 11, 2011 triple meltdown airborne radioactivity blew over the Pacific Ocean to the east of the site with the remaining isotopes from the destroyed reactors raining down on Japanese land.
Even with that ratio, the government created a 12.4 mile evacuation zone that is a no-go area without official permission to enter. About 156,000 people remain displaced by the disaster, the worst nuclear catastrophe ever suffered on the planet, as of early 2013.
San Onofre would likely see the opposite ratio of fission fallout over land and water with most of the deadly cargo moving east over land before falling out. The city of San Clemente, two miles to the north of SONGS along the coast, could bear the brunt of this fallout though the prevailing west wind usually doesn’t blow from San Onofre into town. It usually blows through the plant towards the bulk of Camp Pendleton and Riverside Country to the east.
Nearly 65,000 people live in the tony coastal enclave and some have expressed concern about evacuation routes should SONGS start releasing radiation for any reason. The notoriously crowded San Diego 405 Freeway is the only real escape route which makes rapid evacuation of the city challenging at best.
One of the weightiest problems SONGS’ spent fuel poses is its weight, literally. San Onofre has so many tons of highly radioactive artificial isotopes on site that it makes the facility one of the largest radiation waste storage sites in the country. Unit 2’s core has yet to be removed and weighs in at over 112 tons with Unit 3’s core coming in at 91.5 tons. Respectively, the Units 2 and 3 contain 566.6 and 644.9 tons in their spent fuel pools. Unit 2’s core is still too hot to remove from the reactor core. It weighs another 112.4 tons.
Amazingly, SPFs across the United States don’t have “defense-in-depth” redundant nuclear safeguards. Unlike the nuclear reactor cores themselves, the pools are relatively light on containment. The SONGS pools are 17.5 feet off the ground in a seismically-reinforced building with a 3.16 inch welder liner plate made of stainless steel.
Spent fuel pools aren’t required to have emergency power back-up to make sure the water keeps circulating in the pools should the electricity go out. Some U.S. reactors recently were found to even be lacking gauges which indicate the water levels in the pools. One pool dropped to a potentially dangerous level because nobody bothered to look at it. Indeed, the FOE report says, there are nuclear reactor complexes that have suspect water restoration capabilities.
SCE’s SONGS video says that San Onofre has a 7-day supply of emergency generators fuel. A possible case of sabotage was discovered by SCE in October 2012 when it found someone had poured radiator fluid into one of the generator’s oil-based fuel supply. ABC 10News in San Diego reported last November 30 that the mixture would have caused more wear and could have precipitated the failure of the generator if it hadn’t been detected in a monthly check of the fuel supply. 10News also reported other suspicious acts at SONGS including important bolts that upon inspection were found to be loose and a package looking like a pipe bomb found onsite.
Clearly, reactors rank over spent fuel pools in regards to safety and have the giant concrete domes at San Onofre to prove it. Ironically, the pools catching fire would release vastly greater amounts of radiation into the environment than would a total core meltdown.
Fukushima Dai-ichi’s Unit 4 spent fuel pool has threatened to collapse for over two years but is now being buttressed by a superstructure being built around it. Nuclear experts and pundits alike have predicted that the top third of Japan, including Tokyo, would be lost if Unit 4’s pool crashes to the ground and ignites setting off an unforgettable fire. SONGS has twice as much spent fuel assemblies stuffed into its pools than Fukushima Dai-ichi does.
The fuel assemblies are incredibly hot and kill quickly. A “fresh” spent fuel assembly just out of a SONGS reactor would be radiating in excess of 10,000 rems per hour (100 Sv/hr). At three feet, a person would be fatally irradiated within minutes. Even after 100 years, standing within three feet of the bundle would incur a life-threatening dose.
San Onofre’s spent fuel rods actually pack an extra punch. For 16 years SONGS utilized a contamination-concentrating high “burnup” nuclear fuel that saved SCE considerable amounts of expense. The fuel rods were left in the reactor longer to get the most out of the Uranium-235 energy. It also left them more intensely radioactive than normal spent fuel rod assemblies.
This has increased the temperature and radioactivity in the pools of hot rods. Once dry casked, says the FOE study, these hot boxes need to remain in surface storage to monitor and manage their radiation for up to 150 years before final internment at a high-level radiation dump somewhere yet to be determined.
There is little space left in SONGS’s two spent fuel pools according to 2001 figures. The Unit 1 pool was around 80 percent full and the Unit 2 pool was 82 percent filled. This was 12 years ago. Now stuffed with higher burn up rods, the pools are under even greater stress to cool and clean the circulating water. Neutron absorbing panels are deteriorating and in some cases bulged causing the spent fuel assemblies to be wedged into the under water storage racks. These panels were made initially to help soak up some of the extra radiation generated from the rods by placing them so close together.
“The conservatism/margins in spent fuel pool (SFP) criticality analyses have been decreasing,” says a 2010 NRC report. “The new rack designs rely heavily on permanently installed neutron absorbers to maintain criticality requirements. Unfortunately, virtually every permanently installed neutron absorber, for which a history can be established, has exhibited some degradation. Some have lost a significant portion of their neutron absorbing capability. In some cases, the degradation is so extensive that the permanently installed neutron absorber can no longer be credited in the criticality analysis.”
Worse yet the panels just get in the way of air circulation in case of emergency water loss according to the NRC. In the tightly-packed pool, the fuel assemblies are almost as close to each other as they were in the reactor core, about 9 to 10.5 inches apart. With the panels inserted, air and water circulation are restricted more which could lead to higher temperatures of the pool water.
“Conspicuous in its absence was any mention or discussion in the aftermath of the Fukushima accident by the NRC of reducing the density of spent fuel pool storage, which is substantially greater at U.S. reactors than at the Fukushima site,” says the Alvarez FOE report. “For instance the two pools at SONGS hold a comparable amount of spent fuel as the four damaged reactors at the Fukushima site. Underscoring the NRC’s conflicting claims about spent fuel pool dangers, the U.S. District Court of Appeals June 8, in a lawsuit brought on by Beyond Nuclear and the Natural Resources Defense Council, vacated the NRC’s ‘Waste Confidence Rule,’ found that the NRC had not provided adequate assurance regarding the safety of high‐density spent fuel pools.”
The NRC is playing a nuclear game of ‘chicken’ when it comes to spent fuel pools and it temporarily lost one round June 8. Until the commission produces remedies that will satisfy the court, it can’t license new reactors. Even with that obstacle, where a permanent U.S. repository for the radiating rods and other nuclear detritus can’t be agreed upon, the NRC is still on the hunt to build more nuclear reactors.
“The NRC is participating in pre-application reviews of the DOE’s Next Generation Nuclear Plant (NGNP),” said the NRC in a June 24 report obtained by EnviroReporter.com. “The NGNP would use nuclear fuel comprised of Tristructural-Isotopiccoated fuel particles contained in either fuel pebbles or prismatic fuel assemblies.”
The maximum storage capacity in all operating U.S. reactors will be exhausted by 2015. Yet in response to the historic Court of Appeals Ruling, the NRC took a chapter out of the Environmental Protection Agency’s playbook, as EnviroReporter.com exposed in EPA Nukes Radiation Rules, and simply moved the goalposts and changed the rules.