No matter how hard engineers and scientists work on the Hanford vitrification plant, it will never be perfect, said Frank Russo, Bechtel National project director.
But he is confident that the plant will operate safely and efficiently while protecting the public, the environment and the employees who operate the plant, he said.
His comments were in response to an internal Department of Energy memo made public Monday, in which DOE's engineering division director for the project criticized Bechtel's performance.
The memo called for Bechtel to immediately be removed as the design authority responsible for establishing the design requirements. Bechtel also is designing and building the$12.2 billion plant to turn up to 56 million gallons of radioactive waste left from weapons plutonium production into a stable glass form for disposal.
The memo, written by Gary Brunson to more senior Hanford DOE officials, listed 34 instances in which Brunson believed Bechtel provided design solutions or technical advice that was factually incorrect, not technically viable, not safe for future vitrification plant operators or otherwise seriously flawed.
"DOE engineering staff have uncovered findings at a nearly constant rate since 2008," Brunson wrote. "The rate of identification is constant, indicating systematic problems."
The issues raised in the memo are not new and have been addressed in concert with DOE, some as long as a decade ago, Russo said in a memo to Bechtel staff Tuesday.
Bechtel and DOE jointly have addressed and resolved issues throughout the course of the project, and the technical solutions found have been approved by hundreds of independent experts and external review teams, he said in the memo.
Some issues still need to be resolved and they are being addressed, including issues that have been reopened as new information has become available, he said.
Construction has ramped down at key parts of the plant now to resolve issues that include keeping high-level radioactive waste well mixed within the plant to prevent a nuclear reaction or buildup of flammable gases and to make sure the piping and vessels don't corrode over the 40-year life of the plant. Parts of the plant will be too radioactive for workers to enter to make repairs after operations start.
It's a one-of-a-kind plant with complex challenges and as issues are identified and solutions proposed, "people take very passionate positions," Russo said.
Bechtel provides information and perspective, but ultimately DOE makes the decisions, and those decisions never will have 100 percent acceptance, he said.
Construction on the plant began 10 years ago this month, with the design of the plant continuing to be developed.
The project is challenging, in part, because the 56 million gallons of waste are not homogenous. They were produced in different chemical processes as early as World War II and the chemistry of the waste continues to change, Russo said.
Rather than trying to address every worst-case scenario that is proposed now, Bechtel is proposing that the waste be "preconditioned" to meet set parameters before it is sent to the vit plant's Pretreatment Facility.
"If we choose to solve all potential variations within Pretreatment, some of them hypothetical, the discussion will go on for many years to come," he said. "We will never have 100 percent certainty years into operations."
The biggest risk is to leave waste sitting in aging, underground tanks, he said. Waste from older single shell tanks is known to have leaked in the past and waste in those tanks is being transferred into newer double-shell tanks until it can be treated at the vitrification plant.
But earlier this month, radioactive waste was found between the inner and outer walls of one of Hanford's newer double-shell tanks, raising questions about whether they are deteriorating.
Bechtel also responded to the DOE memo by releasing a point-by-point response to the 34 issues it raised.
The Washington State Department of Ecology still was going through the DOE memo Tuesday but said some of the issues raised were ones it was aware of and had been concerned about, said Suzanne Dahl, tank waste disposal project manager for the state, the regulator on the project.
The state pays keen attention to issues raised in the DOE memo, such as welds and material choices, as it issues permits for the project, she said.
The bottom line is the state expects DOE and everyone DOE chooses to employ to work together to finish a plant that will operate safely and productively for the 40 years needed to treat the waste, she said.
There are difficult tasks to be done, but we "think DOE and its contractors can knuckle down, fix problems and meet their obligations," she said.
DOE released a statement Monday saying that addressing vitrification plant challenges effectively will require more work by the contractor and improved oversight by DOE.
-- Annette Cary: 582-1533; email@example.com