At the hot end of the Cold War: Cleaning Hanford’s water
In southeast Washington, where the Columbia River snakes southward to the Oregon border, a cluster of cities was formed in the mid-1940s with its fortune tied literally to a bomb. Richland, Pasco and Kennewick lie south of Hanford, where, from 1943 to 1989, the United States produced weapons-grade plutonium.
During production and subsequent to waste storage, chemicals and radionuclides leached into Hanford’s groundwater. Today, as the site is being decommissioned and decontaminated, the tri-cities are grappling with the knowledge that, 20 to 30 miles upstream, Hanford’s groundwater is migrating toward their primary water source: the Columbia River.
Unlike the western portion of the state, southeast Washington is arid, receiving only 7 to 8 inches of precipitation per year. As a result, the region relies upon the Columbia River for its drinking water, as well as for agricultural, industrial and recreational uses, and for aquatic habitat.
In addition to being a spawning run for Chinook salmon, the river supports crops ranging from dry land wheat and potatoes to soft fruits. Wineries dot the area, and grapes are one of the region’s major agricultural products.
Protecting the Columbia River will require containment and treatment of Hanford’s existing groundwater contamination and prevention of additional contamination from stored wastes. Cleanup is under way, but decades will pass before the U.S. Department of Energy (DOE), which owns Hanford, can complete its efforts.
In the meantime, tri-city officials are raising funds for the cleanup, actively monitoring its progress and looking ahead to land use plans and economic development. Furthermore, in addition to the real risks harbored at Hanford, officials are battling the threat of perceived risk, which could hinder their efforts to attract new industry, expand tourism and sustain sales of the area’s crops.
Hanford spans 560 square miles and is one of 16 sites that make up the United States’ nuclear “complex.” It, along with the Savannah River plant near Aiken, S.C., produced the nation’s supply of plutonium for nuclear warheads.
Today, Hanford “contains more than two-thirds by volume of DOE’s highly radioactive waste and one-third of all radioactivity created in the nuclear complex,” according to DOE. “It’s probably the most contaminated soil and groundwater site in the United States,” says Suzanne Dahl, project manager for the Washington State Department of Ecology (Ecology), the regulatory agency for Hanford’s storage tank cleanup.
During the production process at Hanford, uranium metal (a fuel rod) was enclosed in cladding and placed in one of nine nuclear reactors in the 100 Area, along the Columbia River. The uranium was irradiated within the reactor and then transported to chemical processing plants, where the cladding and uranium were dissolved and plutonium was recovered and purified. High-level waste resulting from the separation process was stored in underground tanks while less radioactive waste was released to the soil through cribs and trenches, all within the 200 Area or “central plateau.” (See the map on page 21.)
The environmental impact was, in some cases, immediate and expected. For example, the waste beneath the cribs and trenches bound to the soil, which provided a buffer to the groundwater. However, as production increased and more liquid was pumped through the site, the water table rose, and contaminants were pushed through the soil.
Approximately 440 billion gallons of liquid were discharged to the ground at the central plateau, says David Shafer, DOE’s vadose zone manager for Hanford’s high-level waste program. “There’s about 200 to 300 feet of soil between the surface and the groundwater to act as a kind of filtering mechanism for contaminants,” he explains. “And it certainly has some capacity to do that, but it doesn’t have an unlimited capacity, so there were contaminants from those liquid disposal sites that went straight to the groundwater.”
Today, more than 100 square miles of groundwater within Hanford are contaminated above drinking water standards. DOE has identified plumes containing chemicals such as chromium, carbon tetrachloride and nitrate, as well as radioactive contaminants such as technetium 99, cobalt 60, uranium, plutonium, strontium 90, cesium 137, iodine 129 and tritium. According to DOE, groundwater migration from 200 East to the Columbia River is projected to take 20 years, while migration from 200 West could take more than 100 years.
The contaminants of greatest concern to DOE and regulators are present primarily in the 100 and 200 Areas. In addition to the waste from the cribs and trenches, they include high-level waste from past leaks in the storage tanks and from spent fuel rods stored in one of the reactors.
A matter of migration
Hanford’s cleanup efforts began in 1989, when the last of the site’s reactors was shut down. At the same time, DOE, Ecology and the U.S. Environmental Protection Agency signed the Tri-party Agreement, which set forth a 30-year plan for bringing the site into environmental compliance.
In addition to containing and treating the groundwater, DOE must decommission all of Hanford’s facilities; decontaminate and/or dispose of surface structures; remediate contaminated soil; and remove and store waste. All of those processes have the potential to release additional contaminants into the soil and groundwater, but, for now, groundwater project managers are focusing on three goals: pumping and treating existing contamination; removing and storing liquid waste from the underground storage tanks; and removing and storing spent fuel rods.
Last year, DOE completed installation of the site’s fifth pump-and-treat station, which, like its sister stations, is designed to contain rather than remediate the contamination plumes. “The pump-and-treat stations are not designed to clean up the groundwater to drinking water standards,” says Mike Thompson, groundwater project manager for DOE. “They’re only designed to contain the plumes and to stop the migration of the plumes and to reduce mass.
“We have three pump-and-treat facilities along the Columbia River: two for chromium, one for strontium 90,” Thompson explains. “In the 200 West Area, we have two systems: one for carbon tetrachloride and one for technetium and uranium.”
To date, DOE has pumped more than 120 million gallons of contaminated groundwater, which was filtered through resin beds and recharged into the aquifer. Thompson emphasizes that the process is an interim action until the contaminants are removed through either natural degradation or technological means. “The pump-and-treat systems have bought us time,” he says. “They’ve bought us time for the chromium along the river, for the carbon tetrachloride and for a very small plume of uranium and technetium.”
With the storage tanks, DOE cannot report the same progress. Although it plans to vitrify the waste in the tanks (turn it into glass for more stable storage), the vitrification plants will not be in place before 2003, Shafer says.
Of the 177 storage tanks at Hanford, 67 have leaked. Single-shell tanks (149) were built between 1943 and 1964 with design lives between 10 and 20 years. Double-shell tanks (28), designed to last 25 to 50 years, were added to the site between 1968 and 1986.
DOE reports that, together, the storage tanks contain approximately 55 million gallons of radioactive waste, totaling 214 million curies. (See the table on page 29.) Only the single-shell tanks have leaked – estimates range from 0.6 million gallons to 1 million gallons – and some of the contamination has reached groundwater.
The tank waste is moving at a much slower rate than the liquid waste at the crib sites, Shafer says. “The leaks in the tanks don’t have nearly the same hydraulic force behind them than the larger liquid discharges,” he explains. “But it’s very concentrated waste, so that’s why there’s concern about the fact that the tanks now are known to be contributing to groundwater contamination.”
“There’s a big unknown about how far these wastes have moved in the soil column,” Thompson says. “We’ve only drilled two characterization wells since 1989 that go through the tank waste to the groundwater. So the level of information that we have between the bottom of the tanks and the groundwater is really very minimal.
“What we need to thoroughly assess are the risks posed from what has leaked out of the tanks that has not yet gotten to the groundwater, because what we’re seeing now is just kind of the leading edge,” he adds. “So we need to be concerned about what has not gotten to the groundwater; what might leak out of the tanks during retrieval; and what is left behind – because we won’t be able to retrieve 100 percent of the waste.”
Although plans for vitrification are moving forward, the tank wastes must be characterized more fully before the plants can be built. Vitrification has been successful at Savannah River, but the technology must be adapted to handle Hanford’s particular forms of waste. In the meantime, DOE is pumping the waste from the single-shell tanks into the double-shell tanks.
Watchful, but not alarmed
Although they are the nearest downstream neighbors to Hanford, the 120,000 residents of Richland, Pasco and Kennewick are not alarmed by the groundwater contamination, says Kennewick City Manager Bob Kelly. “Given that the Hanford work force has been from this community, there probably has been some general underlying knowledge of a lot of the issues and problems located at the site,” he says.
“We’re confident in the monitoring that’s going on now at the site. Although I think the announcement that the tank farms were actually contaminating groundwater (confirmed by DOE last November) may have raised a lot of eyebrows, it was certainly not a surprise to most of us here locally,” he says.
Residents are concerned, however, and their worries begin with Hanford’s on-site safety and the safety of the cities’ drinking water off-site. “Because most [of the Hanford] workers live in our communities, their health and safety are our concern as well,” says Richland City Manager Joe King. “Our concerns are that, first of all, the cleanup proceeds in a healthy and safe manner for the workers and the environment.
“All the communities around Hanford, and particularly those downstream, draw most of their drinking water from the Columbia River,” he adds. “So we are concerned about the impact that soil and groundwater contamination continue to have on the Columbia River.”
Richland is the only one of the tri-cities that monitors its drinking source independently of DOE. “We monitor the water quality at the pump house, where we extract water from the river. We also have several municipal wells scattered around the city, and those are constantly monitored,” King says.
Radioactivity has not been detectable “beyond background levels,” he notes. “I don’t know that they’ve gone down, but we’re talking about such small portions per volume of water that they’re not a health factor.”
“We can measure tritium and iodine 129 in the Columbia River at Richland,” Thompson says. “The background level for tritium is about 40 picocuries per liter, and we can measure a slight increase in that at Richland. But it’s still 1/250th of the drinking water standard. Iodine 129 is 1/10,000th of the drinking water standard, so it’s present in extremely low values.”
The most easily identifiable source of tritium is one of Hanford’s reactors, where the last of the spent fuel rods were stored in 1989. “In the past, it has leaked a lot of water, and there’s a significant plume of tritium underneath that site,” Thompson says. “Tritium actually becomes part of the water molecule, so it moves fairly quickly with groundwater, and it does go to the Columbia River.”
Although DOE is seeking a way to retrieve and store the fuel rods, the tritium is untreatable, Thompson says. “There’s really no effective treatment methodology or technology available for tritium,” he notes. “It’s got a little more than a 12-year half-life, so the best thing we can do is allow it to move with the water and let natural processes take care of it.”
Common economic purpose
In addition to monitoring its water source, Richland has joined Pasco, Kennewick, Benton County (Richland and Kennewick) and Franklin County (Pasco) on the Hanford Advisory Board, a 36-member group of stakeholders that monitors cleanup and advises regulators and DOE regarding priorities and budgeting. The jurisdictions also have formed Hanford Communities, with the sole purpose of representing the local government agenda. “We decided to join with other local communities because we needed a mechanism to sort through all of the information and pull out the stuff that is really pertinent to us as local municipalities,” Kelly says.
In both capacities – as members of the Hanford Advisory Board and Hanford Communities – the tri-city stakeholders lobby Congress for ongoing cleanup funds. Furthermore, Hanford Communities has undertaken educational programs and is working to enhance future economic development for the region.
“We have a $100,000 contract with the Washington State Department of Ecology that enhances the local government’s role in public education,” says Ben Floyd, economic development coordinator for Benton County. “We’re setting up a speaker’s bureau and producing videos [regarding Hanford’s cleanup] for a cable channel.”
Collectively and individually, the jurisdictions represented in Hanford Communities are working to expand their economic bases. As cleanup progresses, the Hanford work force (approximately 10,000 people today, according to Shafer) will decrease; that fact, as well as the likelihood that parts of south Hanford eventually will be opened up for industrial uses, is driving cities and counties to seek new businesses.
“There are anywhere from 5,800 to 6,000 fewer jobs at Hanford than there were four or five years ago,” Kelly says. “We know that, between now and the end of September, there will be additional layoffs.”
That is bad news for Richland, in particular. “Right now, about seven of every 10 of our households are directly employed at Hanford,” King says. “Employment has gone up and down over the years, but, when cleanup is complete, there will have to be some basic industry here to fill in the employment losses.”
This year, a titanium metal production facility that will produce 100 jobs initially is opening in Richland, King says. He adds that the city recently has developed raw land by installing the infrastructure necessary for additional industrial sites.
“Kennewick tends to be more of a regional retail and commercial center,” Kelly says. “But we’re also interested in expanding our light industrial or manufacturing base.”
“We’re trying to get basic manufacturing – metals industry, food processing – and also focus on tourism,” Floyd says. “We’ve got really a kind of bread and wine basket in the region that people aren’t particularly aware of.” The region’s tourism also is driven by pleasant weather, the Columbia River’s recreational value and golfing.
Holding people still
Joint marketing is under way to promote the tri-cities regionally and nationally. “We have undertaken these marketing efforts, not so much to try to convince anybody not to be afraid of what they hear, but to promote the positive aspects of the area,” King says.
Public misinterpretation of reports from the Hanford site is an ongoing source of consternation for local officials. “The actual risk is the perceived risk,” Shafer explains.
“Information is not always either reported in its entirety or understood by the people who read it,” King says. “You’ve got a constant stream of [information] coming out, and, every time it does, it fills headlines. And people who don’t live here and don’t deal with this every day get quite alarmed. That hurts our image, and it hurts our ability to attract new industry and tourism.
“We have to say, ‘Wait a minute. Yes, contamination enters the river, but it hits the river in a very small quantity, and it’s immediately diluted by the huge volume of the river. There’s nothing different about the water quality by the time it gets 20 miles downstream to where we extract it for drinking.’ It’s hard to hold people still long enough to explain that.”
Floyd views public reaction as a special problem for the counties. Thus far, crop sales have remained healthy, but that balance could shift suddenly, he notes. “If something happens, if you have a tank leak or an explosion, whether the problem was real or perceived, I think we’d see an impact,” he says.
“With the latest hype on the groundwater (DOE’s confirmation that tank waste had contributed to the groundwater contamination), for the first time, folks in agriculture have raised concerns about the fact that they’re pulling water out of the Columbia River. They don’t want to see some sort of backlash similar to what happened with the Alar scare,” he says.
Into the next century
Monitoring cleanup, educating constituents and overseeing economic planning in the shadow of Hanford are likely to remain top priorities for tri-city officials well into the next century. “Some of the cleanup activities are going to take 50 odd years,” Dahl says. “Just to retrieve all the tank waste and put it into glass is a 30-, 40-year project.”
In the meantime, local officials are looking forward to the day when portions of Hanford will be designated as wildlife preserves, recreation and tourism venues, and industrial sites. “We’re trying to get some consistent land use designations that we agree with,” Floyd says. “Then we can start figuring out how we can realize those designations.”
Only the 200 Area seems to be out of question for future land use, Shafer says. “It’s the area of the site that probably will always remain under some type of institutional control,” he says. “It’s unlikely we’d ever be able to release it; it’s simply that contaminated.”
According to Thompson, containment will be DOE’s only feasible option in the 200 Area. “That groundwater is contaminated to the point that it will not be suitable for cleanup,” he says. “We’ll have to contain it and keep if from spreading across the site.”
Throughout the rest of the site, however, DOE is optimistic. “Through a combination of containment actions and source removals, we think that, with time, a good portion of the Hanford site groundwater will actually come back into standards again,” Thompson says.
Already, DOE is getting some help from Mother Nature. “One of the best things we did in the Hanford cleanup was stop the discharge of water to the soil here,” Thompson says. “Because of that, the water table’s dropping and the groundwater is going into tighter and tighter formations. We hope that, through a combination of natural processes and some of the actions that we’re taking, we’ll be able to contain that to a reasonable buffer zone around the 200 Area plateau.
And past it all – beyond the contamination, the science, the engineering and the cleanup – the Columbia River flows south to the cities that depend upon it for their futures as surely as they did for their pasts. “The Columbia River is an absolutely incredible resource,” Thompson says. “We have a big responsibility to protect it from the Hanford site. That is the number one goal in all of our minds; it is the ultimate goal of everything we’re trying to do.”