Drifting traces of radiation from Japan's battered nuclear reactors crossed nearly 5,000 miles of ocean last week to reach the West Coast and Washington state.
The impact is trivial, experts say – no risk to human health.
It’s less clear what the local risks would be if a superquake on the scale of the cataclysm in Japan struck Washington.
The state is home to one nuclear reactor and a vast storehouse of radioactive crud. A smaller heap of the same material, left over from a decommissioned reactor, is kept in Oregon. All three sites nudge the Columbia River.
Is it safe?
The people in charge say yes. The skeptics aren’t so sure.
The reactor in question is the Columbia Generating Station at Hanford, operated by Energy Northwest, a regional utilities consortium.
The crud (the biggest chunk) is 54 million gallons of high-level radioactive waste stored in 177 underground tanks at the Hanford Site near Richland, also known as the Hanford Nuclear Reservation. Some tanks date to World War II. Over the years, 67 of 177 tanks – more than a third – have leaked 1 million gallons of waste.
Miles downriver in Southwest Washington near Longview is a second radioactive storehouse: the grave of the Trojan Nuclear Plant, decommissioned in 1993, its landmark cooling tower demolished in 2006.
The old plant sat on the Oregon side of the river in the town of Rainier, shouting distance from Longview.
The Trojan reactor is gone, its bones shipped upriver to Hanford, but a mausoleum remains, a chamber of waste housed in dry-cask tanks that look like astro-eggs: white shells covering layers of concrete and steel.
HUGE QUAKE UNLIKELY
In one disaster-film scenario, an earthquake cleaves Grand Coulee Dam, and rattles Hanford like a box of marbles. Plant operators and quake experts say it’s unlikely.
The Energy Northwest plant, similar in design to the Fukushima Daiichi plant in Japan, but more than a decade newer, was designed to withstand a magnitude-6.9 earthquake near the plant, such as at Rattlesnake Mountain, said Brad Sawatzke, the plant’s chief nuclear officer.
“Our design and the way we operate the plant is safe for the public,” Sawatzke said last week.
About once a year Hanford has a magnitude 3 earthquake, but the largest since records have been kept was a magnitude-3.8 earthquake in 1973, said Alan Rohay, a Pacific Northwest National Laboratory researcher.
It occurred on the horn of the Columbia River and would have been felt in southern Hanford but would not have had an effect, he said.
A large quake – magnitude 7 – might be expected at Hanford every 5,000 to 10,000 years, Rohay said.
The Columbia Generating Station near the Columbia River was built to withstand floods caused by the loss of dams upstream, including the Grand Coulee Dam, he said.
Those assurances don’t satisfy Gerry Pollet, executive director of Heart of America Northwest, a nuclear watchdog group that keeps tabs on Hanford.
The prospect of an earthquake in or near Hanford raises “a huge risk,” Pollet said, especially in light of Energy Northwest’s plans to use plutonium fuel at the plant, which prompted Pollet’s group to sue the plant operators last week, citing lack of required disclosure.
Pollet points to the active plant and the prospect of a meltdown, but he also cites the vulnerability of old storage tanks and spent-fuel pools near the river.
“The tanks would not survive probably a major earthquake in the range that is potentially predicted now,” he said “Each of those tanks can contain as much radiation as the cores of several reactors, so that’s fairly frightening.”
At Trojan, there’s no plant left: only the dry-cask tanks stored on site.
“You’ve got fuel that’s at least 20 years old, so a lot of the radioactivity and the heat has already gone,” said Ken Niles, nuclear safety division administrator for the Oregon Department of Energy.
“You’ve got irradiated nuclear fuel sitting in very heavy shielded concrete and shielded steel casks sitting basically on a concrete pad. They could certainly tip over – you could probably postulate somehow one would at least rupture in part – but that’s probably the limit of what’s going to happen at Trojan.
“And the thing is that the fuel is a solid it’s not really generating gases.”
Lloyd Marbet, an Oregon environmental activist who watched Trojan for years, doesn’t dispute the description Niles gives, but he also notes that no one predicted the scale of the disaster in Japan.
“In all the history of this debate, a worst-case nuclear accident was always represented to be one reactor having a meltdown and, of course, the response was it was next to impossible,” he said. “Nobody ever, ever talked about four reactors.
“We do the best we can to control this technology, but time and again, we’re getting surprised. It seems to me it’s a time to become more humble about how we approach and represent our control over something that is as lethal as this.”
Sean Robinson 253-597-8486 Sean.firstname.lastname@example.org
The Tri-City Herald contributed to this report.