Monday, February 18, 2013

Hanford: A nuclear disaster in slow motion


A version of this article first ran in the December 2010 edition of the Oregon Insider, a private monthly digest of environmental management and regulatory news. With Hanford in the news this month for a newly reported single-shell container leak, it seems appropriate to publish an updated version of the story.

................................................................................................................................................... 

On Friday, February 15, Washington Gov. Jay Inslee announced the first confirmed leak of high-level radioactive waste at the Hanford nuclear site since 2005. The site of America's first nuclear reactor and one of the largest nuclear waste sites in the world has drawn relatively little of the renewed press scrutiny other nuclear facilities have faced in the wake of Japan's Fukushima meltdown. On the other hand, you might say that Hanford is always in the back of the Pacific Northwest’s mind. The name Hanford has become synonymous with the atomic age and radiation pollution. But how much does the region know about the intricacies of the massive and massively expensive ongoing cleanup effort?

Covering hundreds of square miles of sage-brush filled backcountry on the Columbia River in southern Washington, Hanford is the most contaminated site in the Western Hemisphere. Known by various names, including the Hanford Engineering Works, the Hanford Nuclear Reservation and finally the Hanford site, the complex comprises multiple nuclear reactors, processing plants, laboratories and associated buildings and waste dumps. Because of the nature of nuclear research and production undertaken during Hanford’s four decades of operation, the site’s contamination presents a hugely complex long term problem. While progress has been made, the $2 billion-per-year cleanup is behind schedule and over budget.

Background

The area that would become Hanford has a long history of human occupation. When Euro-American settlers came west in the1800s, they encountered several native nations and long-used indigenous campsites, villages and burial grounds throughout the area. Early farmers scratched a tough living out of the arid basin, cutting irrigation trenches by hand that the flood waters of the as-yet untamed  Columbia would inundate with mud at all-too-regular intervals. The federally-led depression era industrialization of the river promised a vibrant future to those who stuck it out, as dams and irrigation projects sprouted through the interior of the Pacific Northwest.

By the early 1940’s, about 900 ranchers, farmers and townspeople called the 625-square-mile area home. The 300-strong village of Hanford nested in a crook of the Columbia on the western bank of a deep bend in the river known as the Hanford Reach. The larger town of White Bluffs lay six miles up river. Windblown, ashy Columbia Basin soils greedily sucked up water and bedeviled farmers’ efforts to irrigate crops. Underground, water slipped through rifts and seams cut into the basalt bedrock, sliding into a maze of inter-connected and isolated aquifers in a water table that bubbled a scant few feet below the surface in some places and plunged over 250 feet into the earth in others, creeping down-slope to the river at a glacial pace. A drought-tolerant mixture of grasses, wildflowers, willows and shrubs struggled to anchor the dusty soil. Rats, rabbits and deer browsed through the unplowed country while eagles, hawks and a menagerie of lesser avian species wheeled overhead.

For U.S. Army General Leslie R. Groves and his staff, the isolated, sparsely populated countryside – close to the cooling waters of the Columbia and the vast power output of the Grand Coulee Dam – appeared tailor made to needs of the top secret Manhattan Project, America’s Promethean effort to beat Nazi Germany in the race to create a war-ending atomic super weapon. In early 1943, residents of Hanford, White Bluffs and the surrounding countryside learned that their homes and land had been vacuumed up by the secretive war effort as a veritable army of Manhattan Project scientists, engineers and workers swarmed in to create the Hanford Engineering Works. These workers built one of the world’s first functional, water-cooled nuclear reactors right next to the Columbia: a weapons plant that irradiated uranium to create the plutonium-239. The plutonium armed the 1945 Trinity test shot at the White Sands Proving Grounds in New Mexico – the world’s first nuclear explosion – and the 21-kiloton Fat Man nuclear device the U.S. Air Force dropped on Nagasaki, Japan on August 9, 1945.

After World War Two, the government used the Hanford site as the centerpiece of its cold war nuclear arms buildup, commissioning eight further weapons reactors along the river. Engineers from the Atomic Energy Commission (AEC), the bureaucratic ancestor of the Department of Energy (DOE), built five giant plutonium refining and fuel rod reprocessing facilities, along with numerous laboratories and workshops, in three main geographic areas around the site. Hanford eventually became host to a now-decommissioned, government-run experimental power production and fuel refining reactor, known as the Fast Flux Test Facility (FFTF). An operating commercial nuclear power plant owned by the Washington Public Power Supply System (WPPSS) sits on Hanford land leased from the DOE.

Before plutonium enrichment came to a halt with the end of the cold war in the late 1980s, the complex processed 20 million pieces of uranium metal fuel, according to DOE records. Exempted from all federal, state and local environmental standards by the 1952 Atomic Energy Act, the desert lands surrounding the complex became one vast waste dump for radioactive material created on site:  enriched uranium and mixed radioactive byproducts of the production and enrichment cycle such as neptunium, plutonium and americium—known as transuranic waste (TRU)—construction equipment, tools and clothing “crapped up” with radionuclides during use at Hanford.

Pollution levels

Workers poured at least 450 billion gallons of radioactive or chemically contaminated liquid wastes directly into the soil at numerous sites, according to the DOE, which ran the complex for much of its history. The resulting contaminated groundwater plume, covering 230 acres, continues to leach deeper into the ground and stream down slope towards the Columbia.

At least 70,000 drums of plutonium-contaminated waste, plus uncounted metal, wood and cardboard boxes of solid wastes disappeared into more than 40 miles of unlined trenches scratched into Hanford’s powdery soil. The three billion metric tons of contaminated soil could fill a standard football field-sized container 2,000 miles high, as journalist Michael D’Antonio visualizes in his narrative history of Hanford’s effects on the surrounding community, Atomic Harvest.

Workers pumped 53 million gallons of the most highly radioactive liquid waste into 177 underground tanks of various sizes stored in the center of Hanford in “tank farms” of two to 16 tanks. Between 1944 and 1954 the site’s operators built 149 single-shelled, steel and concrete tanks (SSTs) ranging in size from 16 tanks of 54,500 gallon capacity to 25 behemoths capable of swallowing a million gallons of waste each.

Over time, workers pumped different types of high-level nuclear waste (HLW) into the tanks and from tank to tank, sometimes without documenting their actions, creating a strange brew of radionuclides and toxic chemicals that mixed and precipitated and bubbled, forming hard crusts and thick slurries of waste material. Some tanks contained isotopes such as zirconium-95 and niobium-95 that self-heated the slurry to a constant boil. Others produced enough volatile hydrogen gas to threaten spontaneous explosion.

Starting in the 1950s, the tanks began to rupture and leak. By 2000, 68 tanks had leaked at least a million gallons of highly radioactive liquid into the ground, contaminating water in the vadose zone between the ground’s surface and the saturated zone or aquifer. Between 1968 and 1986 engineers built 28 million-gallon-plus double-shelled tanks (DSTs) and began pumping wastes in from the SSTs, a laborious, time-intensive process than involves shooting high-pressure, low volume streams of water into the tanks to break up precipitated material and hard crusts.

For most of its life as a nuclear weapons facility, the Hanford site operated under a strict veil of secrecy. AEC scientists at the site assiduously monitored radiation levels on site and in the neighboring farms and communities, publicly claiming that radiation levels released from the complex were safe while secretly studying the deleterious effects of radioactive Hanford byproducts on humans and animals. They cataloged the airborne release of over 1 million curies of radioactive material from regular plant operations, accidents and experiments such as the now-infamous 1949 “Green Run” test of Soviet-style nuclear fuel reprocessing, which released perhaps 8,000 curies (estimates vary widely) of cancer and thyroid disease-linked radionuclide iodine 131 into the atmosphere. Three Mile Island, the nation’s sole commercial nuclear accident, by contrast, released between 15 and 24 curies of I-131.

At the same time, the riverside nuclear reactors and other facilities released waste streams into the river. Seeps containing radioactive strontium 90, tritium and uranium found their way into the pools of the Columbia Reach, the final free-flowing section of the river above Bonneville Dam and the spawning grounds for perhaps 80 percent of the river’s remaining salmon.

The wall of silence separating the spreading environmental disaster and the public began to crumble as area residents like wheat farmer and Hanford neighbor Tom Bailie started publicly questioning the Hanford complex’s effect on their health.  Reporters posed tough questions about issues like the so-called “death mile” around the site where almost every household suffered from some kind of cancer or radiation-linked disease. The wall came crashing down in 1986 when Hanford manager Michael Lawrence released 19,000 pages of previously classified documents in an attempt to create a climate of public trust and open dialogue between the complex’s leadership and the community. Reporters and activists combed through the documents, uncovering Hanford’s polluted history one leak, discharge and accident at a time.

At the time, the concerns of Hanford “downwinders” – those in the path of the site’s prevailing winds – centered on the massive amounts of radionuclides, I-131 in particular, that the nuclear reactors and processing plants leaked into the air over time. While studies show a clear link between the quickly decaying, highly toxic I-131 and certain cancerous tumors and thyroid disease, it is much more difficult to quantify its effect on the downwinders. The Hanford Environmental Dose Reconstruction Project (HEDR), a local epidemiological study of radiation exposure funded by the DOE before the Centers for Disease Control assumed control, concluded that any potential risk for greater thyroid disease from Hanford’s I-131 emissions was too low to be observed. The National Academy of Sciences (NAS) examined the study and concluded in part that the study used a too-small sample size and overstated its results. Litigation between downwinders affected with thyroid diseases and cancers and the DOE and the contractors that operated Hanford throughout its active years is ongoing.

Cleanup

Beginning in 1989, the mission at Hanford shifted radically, from creating weapons grade plutonium and conducting nuclear research to cleaning up the massive harm done to the 586-square-mile site (part of the original 625-square-mile has been turned back to civilian use) over the preceding four decades. In May 1989, the DOE and the federal Environmental Protection Agency (EPA) signed the Hanford Federal Facility Agreement and Consent Order, or Tri-Party Agreement, with Washington State’s Department of Ecology (Ecology) in response to litigation by the state attorney general’s office over the Hanford cleanup. The agreement helps coordinate the actions of these agencies, which use the authority of three different federal laws to manage the cleanup. While the DOE works under the aegis of the Atomic Energy Act to control nuclear material, the Comprehensive Environmental Response Compensation and Liability Act (CERCLA), known as the Superfund law, directs the EPA’s actions to remediate the site. Under the Resource Conservation and Recovery Act (RCRA), states with hazardous waste laws as tough as the federal standards can assert jurisdiction as the enforcement authority for toxic waste cleanups, as Ecology does at Hanford. The Tri-Party Agreement ranks cleanup priorities, establishes responsibilities and budgets the work, according to the DOE.

The Tri-Party Agreement also provides Ecology with court-enforceable milestones for specific DOE tank farm cleanup actions, says Andrew A. Fitz, senior counsel in the attorney general’s Ecology Division. In 2008, the state attorney general’s office again filed suit against the DOE for missing various Tri-Party Agreement-mandated cleanup milestones, including pushing back the completion date for a Tank Waste Treatment and Immobilization Plant (WTP) that would melt wastes pumped from the tank farms and enclose them in bricks of borosilicate glass for eventual transport and storage in a deep geological storage vault as mandated by the 1982 Nuclear Waste Policy Act (NWPA).

The WTP had originally been scheduled to go online in 2009, but numerous delays pushed that date back to 2011 while the expected cost of the plant ballooned from just over $4 billion to $12.4 billion. The DOE wanted to push that milestone back to 2019, and delay final cleanup of the tank farms from 2018 to 2040. Though experts at Ecology agreed with the federal agency that the work would probably take that long, state regulators worried that without enforceability the timeline would soon be pushed back even further. “I had every confidence that in five years those dates would have slipped into the future,” Fitz said about the WTP competition and operation dates the DOE had volunteered.

The DOE and Washington State settled the case in the fall of 2010 with a consent decree that, while accepting the DOE’s dates, adds new cleanup milestones, creates court enforceability for the first ten years and requires the DOE to work with Ecology to push cleanup dates forward if new technologies or efficiencies can speed up the work. Environmental advocates, however, are not totally satisfied with the consent decree, which pushes final cleanup of the leaky tank farms decades into the future. “The river is at great risk, the health and safety of the Northwest is at risk and the timeline for dealing with these issues does not reflect the urgency of the problem,” said Gerald Pollet, J.D., co-founder and executive director of Heart of America Northwest, a non-profit advocacy group focused on the Hanford cleanup.

Progress

Despite numerous delays and cost overruns, the DOE and its Office of River Protection, created especially for the Hanford cleanup, have made significant strides in decontaminating some areas. In an effort praised by non-profit groups that monitor the Hanford cleanup and act as environmental and public health advocates, the DOE’s contractors have removed 2,300 tons of plutonium-rich spent nuclear fuel rods stored underwater in two million-gallon concrete basins, known as the K-Basins, 400 yards from the Columbia. The basins, built adjacent to the K-East and K-West reactors in the early 1950s, had passed their 20-year anticipated service life and were degrading. The K-East Basin had started to leak contaminated sludge into the ground. To date, all of the spent fuel rods have been removed to dry storage for later processing and one basin has been removed.

In another important cleanup step, safety workers have removed all pumpable liquids from the SSTs, leaving them in what is termed an interim stabilized state. In that condition some liquid wastes – as well as the thick slurries and hard crusts of precipitated chemicals that have built up over time – remain in the tanks. “A tank is considered interim stabilized when it contains less than 50,000 gallons of drainable liquid and less than 5,000 gallons of liquid floating on top of the waste,” as stated in an Oregon Department of Energy (ODOE) white paper on tank waste threats. The ODOE estimates about 30 million gallons of waste remain in the SSTs.

The DOE’s contractors have also retrieved 20 tons of plutonium, including weapons-grade material, from the massive Plutonium Finishing Plant, stabilized and packaged the material and shipped it all off site. The plant, formally a high security area, has been decommissioned and its equipment demolished. The building itself is slated for demolition next year.

Crews have also tackled the vast effort of remediating the 800 known dumpsites at Hanford and 500 riverside facilities. Over half of the waste sites, 482, are now cleaned and 52,000 of the estimated 70,000 drums of plutonium-contaminated waste have been retrieved. 214 buildings near the Columbia have been demolished and 10 million tons of soil and debris removed for storage in the onsite Environmental Restoration Disposal Facility, a lined landfill presently covering the area of 35 football fields that accepts low-level radioactive, hazardous, and mixed wastes according to the DOE’s website.

Five of the nine reactors along the river are now in interim safe storage, their associated buildings and outer layers demolished and the reactor cores cocooned inside a new shield building with temperature and moisture monitoring equipment. The cocooning process should give stabilized radioactive elements in the reactor cores 75 years to cool and decay while permanent storage plans evolve. Workers are now cocooning two more reactors, while B-Reactor, the world’s first full-scale nuclear reactor, has been given National Historic Landmark status and may be included in a proposed Manhattan Project National Park.

Treatment efforts are underway to deal with the spreading contaminated groundwater plume. “We have hundreds of wells across the site to monitor groundwater in places of known contamination, suspected contamination and places where waste might travel,” said Richland-based DOE spokesperson Geoffrey Tyree. Six groundwater treatment facilities on site have cleaned 630 million gallons of contaminated ground water this year, a rate of 53 million gallons per month, and 4.6 billions gallons overall. But Tom Carpenter, executive director of the non-profit Hanford Challenge, warns that the water treatment plan, which only affects the easiest to reach groundwater, may be ineffectual. “Eventually those plumes of contaminated groundwater will recontaminate any area that has been cleaned (between the plume’s present location and the river) and contaminate the river way above drinking water standards,” he said.

Despite the obvious signs of progress, Hanford remains the country’s most complexly contaminated and radioactive site. A 2010 analysis of DOE documentation by former department official Robert Alvarez – which the Energy Department does not dispute according to the New York Times – ups the suspected amount of plutonium waste at Hanford to 11,655 kilograms from the DOE’s claimed 3,919. According to these figures, the plutonium in Hanford’s dirt is equivalent to between 36 and 1,800 World War II-vintage atomic weapons.

Reports on radioactive wild animals from rabbits to mud-dabber wasps appear in the news media, demonstrating the still-contaminated and contaminating nature of the complex. On Nov. 18, the DOE reported contaminated soil emitting radioactivity ten times the lethal limit beneath a building 1,000 feet from the Columbia. Though the contamination is currently capped by the building, once used to examine spent fuel rods, and does not appear to have entered the groundwater, the incident stands as a stark example of the potential for deadly surprises at the Hanford site.

No comments:

Post a Comment