Vit plant ramps up for next phase
Round-the-clock staffing is in place at the Hanford Waste Treatment and Immobilization Plant as Bechtel National Inc. prepares to process low-activity waste by 2023, but possibly as soon as 2022. There hasn’t been 24/7 staffing at Hanford in more than 20 years.
Earlier this year, the analytical laboratory at the plant entered its startup phase, marking the first major facility to begin full systems testing mode.
“We are in phases we have never been before,” said Staci West, Bechtel’s communications manager for the plant.
The overall goal is to process nuclear waste at the site using vitrification, a method of permanently disposing of waste by mixing it with glass-forming materials.
The planning and construction of the plant got underway nearly 20 years ago, at an expected cost of $17 billion, with the end result being the world’s largest radioactive waste treatment plant.
A project commissioned by the U.S. Department of Energy, the completed vit plant will process 56 million gallons of radioactive and chemical waste currently stored in underground tanks, following decades of plutonium production at Hanford. The existing tanks are not a long-term solution for the waste, as dozens are leaking and pose a threat to the environment.
The decadeslong project is a multi-phase operation, beginning with construction, followed by startup procedures, and an eventual transition to commissioning and operation. For example, the analytical laboratory on the vit plant site was only ready to move into the startup phase after 34 systems were tested, with the last being electrical. From there, the equipment and systems will be tested meticulously to ensure they are in working order before the lab enters the commissioning phase, which includes operations. Startup testing at the lab is expected to finish this year.
The first set of 22 commissioning technicians are on the job in the control room of the low-activity waste, or LAW, facility. Working alongside eight supervisors and four engineers, the staff will eventually grow to nearly 350 employees in the next 18 months.
Commissioning technicians are cross-trained on more than 200 systems in the LAW facility, effluent management facility analytical laboratory and other support facilities. Training is done in a 17,000-square-foot building with a full-scale functional replica of the LAW control room.
The purpose of the lab is to confirm that glass produced meets regulatory requirements and standards. Processing will take place during direct feed low-activity waste, or DFLAW, operations, bringing the waste directly from the tank farms, which are managed by Washington River Protection Solutions, and to the LAW facility. It requires the two to work in concert with each other.
“WPRS is also working to design and build the systems necessary to supply the vit plant with a steady diet of waste to support eventual operations,” said Robert Roxburgh, deputy manager of communications and public relations for WRPS. “The tank-side cesium removal system will separate both cesium and undissolved solid materials from radioactive tank waste, providing a low-activity waste stream that can be sent to the WTP for vitrification.”
Benefits of a DFLAW approach are touted as safe storage of long-term waste, reduction of any short-term risks to the environment by targeting mobile constituents, and the creation of additional double-shell tank space.
The analytical lab was intentionally built next door to the LAW facility, where technicians within the lab are expected to analyze about 3,000 samples each year. Since not all waste is identical, the process will determine what materials should be mixed with each sample to create a glass log that meets regulatory requirements. The logs will be stored on the Hanford site until a national repository is identified.
Bechtel and the Department of Energy are working to meet a court-ordered deadline at the end of 2023 to begin treating low-level waste. This date was determined through a consent decree in 2016, which set a legally-binding schedule to retrieve waste from the tanks and continue construction of the plant.
Plant operations were originally expected by the end of 2018 but after problems arose with the high-level waste and pretreatment facilities, the project shifted focus to DFLAW configurations instead. This now includes the Dec. 31, 2023, deadline for treating LAW, and a Dec. 31, 2033, deadline for treating high-level waste.
Goals for the remainder of 2019 include delivering all DFLAW major equipment and bulk materials, completing the startup of the analytical laboratory and installing equipment necessary for the final support structure, the effluent management facility, or EMF.
There are 20 support facilities that make up the Balance of Facilities, or BOF, on the campus, with 14 dedicated to low-activity waste and the remaining six to be built in future phases to treat high-level waste. The EMF is part of the DFLAW process, receiving secondary liquids generated from the LAW facility to be treated and transferred to the liquid effluent retention facility, which sends back any remaining concentrate to go through vitrification.
Bechtel is planning to simulate a loss of power during a test planned in fall 2020 to ensure the facility’s melters would remain functional despite a blackout. Bechtel leadership calls this a “crucial” test toward moving into the operation phase for the LAW facility. The melters are considered the heart of the vitrification process since they heat the waste and chemicals so they may be turned into glass form.
The loss-of-power test is one of many processes described as “methodical,” encompassing a series of reviews paired with rigorous documentation.
“As we meet different milestones, we can do the next set that we haven’t done before,” said George Rangel senior communications specialist at the vit plant.
Rangel said as crews prepare to hand over any facilities from startup testing to the commissioning phase, “workers are hands on to develop processes and procedures that will govern their work.”
As the procedures roll along, the plant’s workforce needs also shift.
Right now, about 2,600 people work at the site, but eventually that number is expected to fall to 1,500 to 1,800.
“Once we start operations, there will be a steady workforce for DFLAW,” West said. “It will be smaller than what was required to build it, but there will still be a steady workforce.” This includes transitions from construction workers to chemists, who will be needed on the commissioning team. Some of these chemists currently are working inside a lab at Columbia Basin College to ensure workers train on the same equipment they will eventually use in the analytical laboratory.
“In the next one to two months, some of those workers will begin working out of the lab for the first time,” West said.
Startup and testing also recently got underway for four utility buildings that are part of the support infrastructure that make up the BOF on the vit plant site, containing 56 systems. The utility buildings include the anhydrous ammonia facility, former glass storage facility, chiller compressor building and steam plant building. All are scheduled to complete the startup phase within 2019. Bechtel promotes that once complete, the BOF will have a chilled water system that could cool 23,500 houses, a fuel oil storage that could fill the gas tanks of 11,500 cars and a compressed air system that could fill the Goodyear blimp in three minutes. About half of the BOF systems are in the commissioning phase, another 24 are in the startup phase and the final five are preparing to be turned over from construction to startup.
When complete, the “first-of-a-kind project” will cover 65 acres and include four nuclear facilities covering pretreatment, the analytical laboratory, LAW facility and high-level waste facility, besides other operations and maintenance buildings, utilities and office space.
The footprint of the plant itself is equivalent to the size of 1.5 football fields and 12 stories high. Bechtel describes the vit plant as a “feat of engineering and construction at an unprecedented level,” making it the “largest undertaking of its kind and one of the Department of Energy’s most technically challenging cleanup projects.”