Hanford Challenge has joined criticism of the Department of Energy for spending eight years on a comprehensive study of cleanup of Hanford's radioactive tank waste without coming to a decision on how to treat all of the waste.
The report does not meet legal requirements, the group said.
Federal law requires DOE to select its preferred cleanup methods in environmental impact statements such as the newly completed Final Tank Closure and Waste Management Environmental Impact Statement, according to Hanford Challenge.
"The failure of the Energy Department to declare a cleanup preference for vitrifying much of Hanford's radioactive waste is an irresponsible waste of time and taxpayer money," said Tom Carpenter, Hanford Challenge executive director.
The study and resulting document, which Hanford Challenge counted at about 10,000 pages, cost $85 million.
The Seattle-based group also is questioning one of the conclusions that DOE did reach in the document -- a recommendation that once 149 underground tanks are mostly emptied, they remain in the ground.
The 1 percent of waste that could be left in the tanks plus the estimated 1 million gallons of radioactive waste that leaked from the tanks in the past will continue to contaminate the soil, the groundwater and the Columbia River for thousands of years without a more complete cleanup, according to Hanford Challenge.
"Priority must be placed on remediating leaked contamination to protect the groundwater and Columbia River," Carpenter said. "It will be expensive. However, protecting current and future generations, the Columbia River and ecosystem of the Hanford Reach is well worth it."
All the waste that has leaked from the tanks to the soil beneath them cannot be cleaned up if at least some of the tanks are not removed from the ground, Carpenter said.
Carpenter questioned the legality of not making a decision on how to treat all 56 million gallons of tank waste in the environmental study at a web-based briefing for the Hanford Advisory Board last week. The waste is left from the past production of plutonium for the nation's nuclear weapons program.
The $12.2 billion vitrification plant under construction may be able to treat as little as one-third of the low-activity waste in a reasonable time, and 90 percent of the waste in the tanks is expected to be separated out and classified as low activity waste.
The final report on the environmental study considers grouting the waste, using steam reforming to treat it, expanding the waste treatment plant to vitrify all the waste or using bulk vitrification to glassify the waste in large blocks the size of land-sea shipping containers.
However, the report does not pick a preferred alternative.
DOE has not publicly addressed the question of whether it was legally required to choose a method.
Instead, it sent the Herald a statement saying that "DOE believes it is beneficial to further study the potential cost, safety and environmental performance of alternative treatment technologies."
The Hanford Advisory Board in June recommended that DOE discontinue efforts to study bulk vitrification, grouting and steam reforming for tank waste treatment.
Washington state, the regulator for tank waste treatment, also does not support waste treatment methods that do not vitrify the waste, saying all would produce waste forms that would release more radioactive material to the environment that vitrified waste forms.
The study analysis clearly supports expanding the vitrification plant by adding a second Low Activity Waste Facility as the only environmentally protective option for supplemental treatment, according to the state Department of Ecology. It also said the report was incomplete without a recommendation for a treatment method.
Hanford Challenge called the decision to leave up to 1 percent of the difficult-to-retrieve waste in the tanks, add grout and bury the tanks in place a "disappointment."
If that happens, previously leaked waste beneath the tanks and the remaining 1 percent of the waste eventually would contaminate the Columbia River, it said, based on information in the study report.
The study report agreed that "past leaks are major contributors to potential long-term groundwater impacts."
DOE responded to Hanford Challenge's concerns with a statement saying that leaving tanks in place may require soil removal or treatment.
The soil is contaminated to 225 feet deep below some tanks, in part because of past practices of discharging contaminated liquids to the soil in central Hanford, according to the study report. But in other places, the contamination is not as deep.
The study report mentions options such as technologies that dry out soil between the ground surface and the groundwater, which could help keep contamination from spreading. In addition, other new ways to sequester the waste beneath the ground's surface without digging it up could be considered.
However, there are uncertainties about the effectiveness of using advanced technologies on contaminated areas, particularly with the size of contaminated areas unknown, the study report said.
DOE recommended against digging up the tanks, based on worker safety and technology concerns, according to the study report.