Hanford From Space Google Earth |
The last
several weeks we’ve been talking and reading about nuclear waste storage in
preparation for a forum Gallatin hosted in late September that included several
different points of view on the Hanford cleanup, in my mind the country’s most
important environmental project.
Gallatin
has a special resource on nuclear waste, John Kotek, the new head of our Boise
office. For the previous two years, John
was staff director for the President’s Blue Ribbon Commission on America’s
Nuclear Future where he worked with some top people who are struggling with the
complexities of finding a place to store the high-level detritus of the
country’s nuclear programs, nearly 70 years after they began. John, a nuclear engineer, also brings the
experience of administering the Federal Department of Energy contract for the
programs of the Idaho National Laboratory.
The panel
at the forum included our man Kotek as well as Jane Hedges, the Washington
State Department of Ecology manager who runs the state’s nuclear waste program
and represents the state’s interest at the Hanford cleanup site. Our third expert was Ward Sproat, who came
out of the civilian nuclear power industry in Pennsylvania and was appointed by
President George W. Bush to oversee the license application for the proposed
nuclear waste repository at Yucca Mountain.
Sproat is widely known within the industry to have turned that project
around, though Yucca Mountain has since been taken off the table by President
Obama at the urging of Harry Reid, Senator from Nevada and a staunch
opponent. Sproat has joined the Bechtel
National team working on the Waste Treatment Plant at Hanford, which will
stabilize nuclear waste and other contaminants there by fusing the waste into
glass logs.
Single-wall tanks under construction, 1944 Department of Energy |
We asked
each panelist to give a status report from their unique point of view. Hedges reported that the state sees
considerable progress in Hanford cleanup.
She cited as a key risk-reducing accomplishment the fact that most of
the liquids residing in the old single-wall waste storage tanks, have had their
liquids pumped into newer, double-wall tanks.
What remains in the old tanks is a semi-solid, dry cake-like substance
that contains a great deal of radioactivity but is far less likely to
leak. She pointed out, however, that the
double-wall tanks are also getting older and recently a leak was detected in
one of them – into the space between the two walls.
Cocooned C Reactor Department of Energy |
Hedges also
said that the process of cocooning the plutonium producing reactors was
continuing with six of the nine nuclear reactors sealed in cement and steel
that will isolate the hot reactor core for up to 75 years. Once sealed, the facilities are monitored
remotely for heat and moisture. Every five years, workers enter the structure
to evaluate its condition and to ensure there are no avenues for intrusion by
animals or the elements.
Making
plutonium at Hanford was a messy process that required nuclear reactors to
irradiate uranium fuel assemblies. Some
of the uranium in the fuel assemblies was converted to plutonium. The plutonium
was separated from the uranium using a caustic chemical slurry that created a
great deal of waste in the process. The
result is weapons-grade plutonium that is 93-94% pure and, when suddenly
compressed inside a weapon, initiates a chain reaction explosion of
considerable force. The bomb at Trinity, New Mexico was made with Hanford plutonium as was the bomb dropped on Nagasaki.
During
World War II and the Cold War that followed, many different reactors were
constructed and several different extraction processes used. The result creates huge technical challenges
to clean-up because the character of the waste varied from process to process.
Hedges said
that the vitrification process that has been chosen for Hanford is the right
technology, but because of the complexity of the waste, still faces technical
challenges to the mission of incorporating waste into glass logs for permanent
storage.
Sproat said
that the plant is now more than 60% complete.
The glass log technology has been successfully used in the US and in
France, but the combination of the wastes and chemicals at Hanford, the
different sizes of individual parts of the waste and other evolving information about
the character of the waste make it difficult to complete design and finish
construction of the vitrification plant.
Sproat’s company is involved in successfully decommissioning tanks and
vitrifying the waste at the Savannah River complex in South Carolina, although
the waste there is less complicated than the Hanford waste.
A third
component of the discussion was what to do with the waste after it is
processed. For now, and for the
foreseeable future, Kotek said high-level waste and commercial nuclear fuel
rods will have to stay in place. He said
the Blue Ribbon Commission had come to the conclusion that a top down,
federally mandated site solution would be riskier and more expensive and Kotek
said that the commission was recommending a consent-based approach. He said that recent successful public
processes in Finland, Sweden and Spain led the commission to believe that there may be a better way to talk to communities about hosting nuclear waste storage.
Kotek said the Commission also recommended a change of governance for nuclear waste storage, from the federal Department of Energy to a new, single-purpose government corporation with responsibilities to “site, license, build, and operate facilities for the safe consolidated storage and final disposal of spent fuel and high-level nuclear waste at a reasonable cost and within a reasonable time frame.”
Legislation to accomplish this task has been introduced in the current session of the Congress and will spark a long-needed conversation about United States’ goals for its nuclear waste programs. We tend to think of Hanford as focused on turning highly radioactive waste into glass logs, but the cleanup is an enormous undertaking with many components and a cost of two billion dollars/year.
Hanford B Reactor, the First Plutonium Reactor Department of Energy |
Good and convenient sources allow the lay person to get a grasp on the history of waste at Hanford. In 2003, the Pacific Northwest National Laboratory wrote a short history of waste at Hanford and set out just what kind of materials were put into the 1600 disposal sites that served nine nuclear power plants and five plutonium processing facilities. Used in tandem with the Department of Energy’s Hanford website, it is possible to update and enrich this remarkable history.
“From 1944 through the late 1980s, Hanford generated nearly
525 million gallons of high-level tank waste.
Liquid evaporation, discharge to the ground, chemical treatment and tank
leakage reduced this volume by 90%— to 54 million gallons. This is about 60% of the tank waste existing across
all U.S. Department of Energy nuclear activities. Today, this waste contains
about 195 million curies of radioactivity and 220,000 metric tons of
chemicals,” the PNNL report says.
Hanford Tank Complex, About 1953 |
“Even with
149 tanks, the volume of chemical wastes generated through the plutonium
production mission far exceeded the capacity of the tanks. Some of the liquid
waste did end up being put into holding facilities and some was poured into
open trenches. Some of the wastes that were put into the tanks didn’t stay
there, as the heat generated by the waste and the composition of the waste
caused an estimated 67 of these tanks to leak some of their contents into the
ground. Some of this liquid waste migrated through the ground and has reached the
groundwater.”
With the shutdown of the N Reactor in 1987, no more
plutonium has been made there. Over the
years the double-wall tanks have received liquids originally put into the single-wall
tanks, providing better protection.
PNNL’s 2003 history reported that no double-wall tank had leaked, though
some of those were reaching their design life.
As Jane Hedges reported during the panel discussion, a double-shell tank
was recently found to have leaked into the space between the inner shell and
the outer shell.
Spent nuclear fuel was stored on site as well, about 2,100
tons. The fuel was irradiated in the N
Reactor, the dual-purpose reactor that produced plutonium for weapons and steam
for electricity. The fuel was then moved
to two aging, water-filled concrete basins and never reprocessed, sitting in
the water for years. The report says
that some of this fuel corroded and radionuclides migrated to the local soil
and ground water. However, after 2003, that basin water was treated and
disposed (Hanford cleanup treats 28,000,000 gallons of water each year) and the
fuel assemblies have been taken out and stored in carbon steel tubes. They reside today in what is called the
“Canister Storage Building,” where it and Waste Treatment Plant steel canisters
holding vitrified waste will be stored until a national repository is built.
There has also been some progress made in stabilizing the
old single-wall tanks. By the middle of
last month, three single-wall waste tanks had been emptied this year, bringing
the number of emptied tanks to ten. Some
contain small amounts of material that has hardened on the floors of the tanks
and will require additional work before full decommissioning.
Low Level Nuclear Waste Disposal, Hanford 1950 Department of Energy |
Handling
radioactive materials creates radioactive garbage. Refrigerators, ovens, old
clothing, shoes, pumps, equipment, vehicles, railroad cars – all the tools of
long-ago experimentation and testing must be buried or put into containers for
storage and future disposal.
Plumes of
radioactive and hazardous material are moving toward the Columbia River from
land disposal and leaks. Depending on
the contaminants, some move slowly and others move with considerable
speed. The cleanup effort must monitor
these plumes and manage their movement.
The PNNL history
says that 110 million curies of radioactivity were discharged into the
Columbia, a significant number, though a large percentage of the discharge was
in elements with short half-lives.
Magnesium, for example, with a half-life of just over two and a half
hours, accounts for two-thirds of the curies discharged into the river. The history says that the largest releases
into the Columbia occurred in 1963 when eight reactors were working and
plutonium production was at its zenith.
In those days, a typical resident, according to PNNL, would receive one
to five millirem/year over normal background radiation, a relatively small
amount. However, a frequent user of the
Columbia who worked on the river and has a significant amount of fish in his diet
would have experienced a 50-130 millirem dose, 15%-45% above background
levels. The PNNL study says that Native
Americans exposed to those 1963 levels and who also consumed a lot of river
fish would have been exposed to fifty times more radiation than exists in the
natural background. Today, none of the
reactors built for plutonium production are working and two-thirds are cocooned
and none of the plutonium reprocessing plants are operating. Called canyons, because of their length and
high walls, these plants remain shut down but still are highly radioactive.
A Hanford
cleanup agreement between the Department of Energy, the Environmental
Protection Agency and the State of Washington Department of Ecology was agreed
to in 1989 with the leadership of then Attorney General Chris Gregoire and was
updated in 2009 with a court-supervised consent decree. The agreement covers many different disposal
sites across the reservation. Most of
these materials will have to remain on site until a national nuclear waste
repository is found, studied, approved, permitted and built.
The clean-up at
Hanford is a legacy issue, depending on stable funding over many years – the
current schedule calls for continued intense efforts along many fronts. Not all of these fronts have a secure
end-date. Also, future funding for
Hanford cleanup and for a new, national repository to store what is removed at
Hanford depends on the congressional appropriations process, even though
commercial nuclear plants set aside today some $750 million a year for a
national repository. This money is
considered revenue by the federal government and is not, as originally
contemplated, a fund of its own. Getting the money requires the appropriations process.
Making funding even more difficult is the fact that the federal
government is completing some of its cleanups in other parts of the
country. Twenty-nine states were part of
America’s nuclear program and needed various levels of cleanup. Today, however, 15 of those have moved from
cleanup to monitoring, making the issue less urgent to Congressional
delegations in those states where the cleanup is finished.
Seventy years ago, in December 1942, a group of scientists toured the Hanford Site, one
of a handful of sites under consideration for the world’s first plutonium
factory. They knew that the science of
nuclear energy was widely shared among scientists and academics around the
world before World War II and that the Nazis both knew about the atom’s
potential as a weapon and had demonstrated great innovation and success making
new weapons. They knew that in December
1942, the Germans appeared to be in command at Stalingrad, owned nearly all of
Europe and the Mediterranean Sea and were raining bombs on London. The scientists were in a hurry to produce an
American atomic weapon and left us a shorter war and highly contaminated place
in the center of our state next to our great river.
Under the
best of circumstances, cleanup will be ongoing well into the middle of this
century with the areas under active cleanup becoming smaller and concentrated
toward the center of the site, away from the river. In a way, it is a kind of cathedral. People working on it today will never see it
finished, though it is one of the most significant public works our country will ever do. It creates amazing and difficult management
problems that require a focus on tomorrow’s end game while solving today’s immediate and difficult problems.
Department of Ecology Waste Program Website
Short History of Hanford Project
Department of Energy Hanford Cleanup Website
Vitrification Plant Summary
Department of Ecology Waste Program Website
Short History of Hanford Project
Department of Energy Hanford Cleanup Website
Vitrification Plant Summary