Completing the steam plant and placement of structural steel in the main portion of the High-Level Waste Vitrification Facility were just two of the major construction accomplishments the Bechtel team made in 2013 at the Hanford Waste Treatment Plant.
In southeastern Washington State, Bechtel is designing, constructing and commissioning the world’s largest radioactive waste treatment plant for the U.S. Department of Energy (DOE). When complete, the Hanford Tank Waste Treatment and Immobilization Plant (WTP), also known as the Vit Plant, will process and stabilize 56 million gallons of radioactive and chemical waste currently stored at the Hanford Site.
Chief among the construction accomplishments was placement of the structural steel to the 77-foot level at the High-Level Waste Vitrification Facility. The building is among the core elements of the Waste Treatment Plant, which also includes the Pretreatment and Low-Activity Waste Vitrification facilities as well as the Analytical Laboratory.
“Construction is in full swing in most areas of the plant, including areas of High-Level Waste Facility not impacted by technical decisions,” said Bechtel’s manager of construction at the Waste Treatment Plant, Steve Overton. “In addition, we completed a substantial amount of work at the Analytical Laboratory, which puts us in a good position to complete construction of the Lab in 2014,” Overton added.
Another significant construction accomplishment in 2013 was the completion of the steam plant. The plant is part of the infrastructure necessary to support the four main Waste Treatment Plant facilities.
Vitrification involves blending waste with glass-forming materials and heating it to 2,100 degrees Fahrenheit (1,149 degrees Celsius). This mixture is then poured into stainless steel canisters to cool and solidify. In this glass form, the waste is stable and impervious to the environment, and its radioactivity will safely dissipate over hundreds to thousands of years.
While vitrification has been employed successfully at other radioactive waste clean-up sites, it has never been attempted at the scale of or on waste as complex as that stored at Hanford. The WTP Project is a feat of engineering and construction at an unprecedented level. It is the largest undertaking of its kind and one of DOE’s most technically challenging clean-up projects.
The WTP Project is equivalent to building two nuclear power plants and is being accomplished at a time when a new nuclear facility has not been built in the U.S. for decades. The construction site spans 65 acres and includes four major nuclear facilities – Pretreatment, Low-Activity Waste Vitrification, High-Level Waste Vitrification and the Analytical Laboratory. The largest of these structures, the Pretreatment Facility, has a footprint equivalent to four football fields and will be 12 stories tall when complete. Operations and maintenance buildings, service utilities and office space complete the complex that overall requires more than 260,000 cubic yards of concrete, 40,000 tons of structural steel, and more than one million feet of piping.
A leader in environmental cleanup and restoration of former nuclear weapon production sites, Bechtel has experience that includes the cleanup, remediation, and closure of high-level nuclear waste facilities in Washington State, New Mexico, and South Carolina.
Click here to watch video of the progress.