SRS Reaches Milestone in Construction of Large-Scale Disposal Unit
Workers build the roof of the mega-unit Saltstone Disposal Unit (SDU) 7, at right. Construction of the SDU 7’s outer shell was completed Dec. 6. Also pictured are the construction sites for SDU 9, top, and SDU 8, left, along with the completed SDU 6, center.
AIKEN, S.C. – EM and its liquid waste contractor at the Savannah River Site (SRS) completed construction of the outer shell of the site’s second large-scale saltstone disposal unit on Dec. 6.
Saltstone Disposal Unit (SDU) 7 is a permanent disposal facility designed to hold 32 million gallons of saltstone, a non-hazardous waste form produced by mixing decontaminated salt waste from the site’s high-level tank waste with dry materials to create a cement-like grout.
The structure — 43 feet high and 375 feet in diameter — comprises 14 floor sections, 25 wall sections, and seven roof sections each made of high-strength, reinforced concrete. Two hundred and eight columns support the roof, and 1,915 tons of rebar reinforce the concrete in the SDU shell.
“We are pleased with the progress on SDU 7,” DOE-Savannah River SDU 7 Federal Project Director Shayne Farrell said. “Each step completed along the way is further proof of successfully continuing DOE’s waste disposition mission at the Savannah River Site.”
The next step, which is expected to be completed in the spring, involves wrapping the outside of the unit with seven layers — 341 miles — of steel cable for added strength. An interior rubber liner will be installed once the cable has been added.
SDU 7 is scheduled to be ready for operations by spring 2022.
Work is also ongoing on the next two mega-units, SDUs 8 and 9. A leakage detection system has been installed for SDU 8. This system, just like what was installed in the previous seven units, comprises a geosynthetic clay liner and high-density plastic liner sandwiched between two concrete layers called “mud mats.”
Initial excavation for SDU 9 has also been completed, and the leak detection liner and mud mat installation will follow. SDUs 8 and 9 are being built simultaneously, optimizing crews and resources and ultimately cutting costs.
SDU 7, as well as future additional SDUs, are being constructed to safely and permanently store the large volume of decontaminated salt solution to be generated at the Salt Waste Processing Facility (SWPF), the salt waste treatment facility currently undergoing testing and commissioning. Five SDUs are scheduled to be constructed in addition to SDUs 6 and 7.
SWPF will process salt waste at much higher rates than ever accomplished on-site by a previous pilot-scale facility, making the mega-SDUs critical components of waste disposition at SRS.
Savannah River Remediation (SRR) is EM’s liquid waste contractor at SRS.
-Contributor: Colleen Hart
Mock-ups Prove Effective in Testing Idaho Waste Treatment Facility
IDAHO FALLS, Idaho – EM and cleanup contractor Fluor Idaho have been working with a local small business to create mock-ups of critical equipment needed to treat 900,000 gallons of liquid radioactive waste from underground tanks at DOE’s Idaho National Laboratory Site.
Diversified Metal Products, an Idaho Falls-based metal fabrication shop, developed mock-ups of the Integrated Waste Treatment Unit’s (IWTU) primary reaction vessel, the Denitration Mineralization Reformer (DMR), and a process gas filter as EM prepares the treatment facility for operations.
The mock-ups have been used to test the ability to decontaminate the facility’s processing cells prior to changing filter bundles during eventual IWTU operations. They were also used to train radiological protection personnel and to develop remote tools for anticipated maintenance activities.
Engineers used the DMR mock-up to assess the capability to decontaminate the vessel during operations in the event that waste treatment operations are curtailed to replace equipment or to empty the reaction vessel, according to Fluor Idaho Chief Engineer Joe Giebel.
The engineers also tested decontamination technologies, which are needed so engineers and operators can replace equipment, such as valves, during actual waste treatment operations.
“The testing of both wet and dry decontamination technologies was quite successful using the mock-ups,” Giebel said.
Canister decontamination technology undergoes testing for use in the Intergrated Waste Treatment Unit at DOE’s Idaho National Laboratory Site.
The wet decontamination technique involves transferring liquid waste to a vessel so it can later enter the steam reforming unit. In the steam-reforming process, superheated steam enters small nozzles of the DMR to suspend and fluidize billions of tiny beads. Liquid waste is injected among the superheated beads, which are coated with the waste and converted to a carbonate product, like the creation of a pearl.
During dry decontamination activities, a dry vacuum system transfers a granulated solid waste from the DMR to a canister fill system.
“Using mock-ups has been beneficial in resolving technical challenges,” Giebel said. “Testing on a full-scale mock-up gives us a sense of realism that you can’t get from a computer-generated graphic.”
Diversified Metal Products previously worked with IWTU’s engineers on a mock-up of the DMR to create prototypes of the auger-grinder, which transfers treated waste material to downstream processes. Testing by the small business led to a successful design for the auger-grinder, with more robust “teeth” and an improved motor.
The IWTU has undergone six demonstration runs since it was built. During the latest 50-day run, operators converted more than 63,000 gallons of a liquid simulant into a dry, granular solid.
Following additional equipment modifications and installation of new filters to improve the efficiency of the process gas filters, the IWTU will conduct another run next year before actual waste treatment operations begin.
-Contributor: Erik Simpson
Basin Demolition Underway as Oak Ridge Heads Toward ETTP Cleanup Completion
Crews remove concrete subsurface structures of the K-832 basin. UCOR pumped nearly 2 million gallons of water from the basin before beginning demolition.
OAK RIDGE, Tenn. – A basin that once held cooling water used in Oak Ridge’s former uranium enrichment operations is being demolished as EM works to complete cleanup at the East Tennessee Technology Park (ETTP). Watch a video of the project here.
Workers have begun demolishing the K-832 basin in the Poplar Creek area at ETTP. It was used in conjunction with a pumphouse and cooling tower, both of which were demolished by EM crews in 2017.
The below-ground basin contained more than 2 million gallons of nonradioactive water. Oak Ridge cleanup contractor UCOR pumped out most of the water to prepare for demolition.
Workers shifted the remaining water to one end of the basin to continue dewatering as crews begin demolition on the other side of it. Remediation of the basin site is expected to wrap up early next year.
“EM and UCOR finished removing all of the major buildings in the Poplar Creek area earlier this fall, and now we are able to address the slabs and underground structures left behind,” said James Daffron, acting ETTP portfolio federal project director. “Removal of this basin is another step in restoring the environment and transforming ETTP.”
Crews finished taking down the last of the 11 main buildings in the Poplar Creek area in September. That effort, which began in 2017, eliminated the most contaminated facilities remaining at the ETTP and removed the last of the buildings associated with the site’s gaseous diffusion uranium enrichment operations.
Demolishing the basin is part of EM’s broader objective to finish major cleanup at ETTP by the end of next year — a goal known as Vision 2020. Environmental cleanup at ETTP is removing risks, transforming the landscape, and enabling land transfers that open the door for new economic development.
EM’s ultimate vision for ETTP is a multi-use industrial park for industry, historic preservation attractions, and conservation areas.
-Contributor: Wayne McKinney
EM Completes First Tank Closure Phase Using Innovative Technology at SRS
AIKEN, S.C. – EM recently declared the first phase of closure complete for an underground waste tank central to a pilot project designed to accelerate cleanup at the Savannah River Site (SRS).
The first phase of closure is known as bulk waste removal efforts. The demonstration project, called Tank Closure Cesium Removal (TCCR), was designed to speed removal of radioactive waste from the SRS underground tanks to support tank closures.
DOE-Savannah River Assistant Manager for Waste Disposition Jim Folk oversees the liquid waste program at SRS.
“Every milestone is carefully planned and executed, and this is another example of the great progress being made to ensure the safety of our workers, the environment, and our community,” Folk said. “It is exciting to see the use of innovative technologies leading to tank closure.”
Savannah River Site waste tanks nine through 12, during construction in 1953.
An aerial photo of Savannah River Site tanks nine through 12 in 2019.
TCCR is a waste treatment technology that uses filters, ion exchange columns, and a specially engineered resin to remove cesium — a radioactive chemical element — from the salt waste.
EM and Savannah River Remediation (SRR), the liquid waste contractor at SRS, completed bulk waste removal efforts for Tank 10 on Oct. 31, about a month ahead of a federal facility agreement milestone.
Tank 10 is one of 43 operational waste tanks that hold radioactive liquid waste at SRS. The bulk waste removal efforts for Tank 10 consisted of four campaigns. In 1967, one campaign removed sludge waste. The remaining campaigns removed salt waste through the addition of water to the tank, also known as salt dissolution, occurring between 1979 and 1982, in 2013, and in 2019. Low-level salt waste accounts for more than 90 percent of waste in the SRS tank farms.
During the 2019 Tank 10 bulk waste removal efforts, over 200,000 gallons of dissolved salt waste was processed and decontaminated through the TCCR unit and subsequently moved to Tank 50. Tank 50 feeds the Saltstone Production Facility, where decontaminated salt solution is to be mixed with a dry mixture that turns it into saltstone for permanent disposal in Saltstone Disposal Units (SDU).
“Completing Tank 10 bulk waste removal efforts ahead of the November 30, 2019, schedule date is one of many major steps in readying a waste tank for operational closure,” SRR Tank Closure and Regulatory Director Jhivaun Freeman-Pollard said.
“SRS is constantly looking for ways to improve processes and to ensure we are being good stewards of taxpayer dollars,” DOE-Savannah River Nuclear Materials Manager Maxcine Maxted said. “This reallocation of resources from HB Line to SRNL is an example of how we accomplish that.”
Shipping and receiving personnel with EM contractor Savannah River Nuclear Solutions (SRNS) had supported plutonium oxide production at HB Line, a chemical processing facility. The material was produced to make fuel for commercial power reactors, or shipped for disposal.
HB Line personnel required unique certifications and equipment to support shipping and receiving of special nuclear materials. That mission ended last year and the facility is being placed in safe shutdown status. When the need to support SRNL shipments became apparent, HB Line operations personnel were made available for that work, and have completed 13 safe shipments for the laboratory since November 2018.
“Our folks were interested in helping out, and it made sense based on the infrequency of our HB-Line specific shipments in support of safe shutdown,” SRNS HB Line First Line Manager Brooks Hubbard said. “It afforded us additional opportunities to remain proficient in shipping and receiving operations. Working with SRNL, we developed a plan to have our employees support the nuclear material shipments.”
The need for personnel for the SRNL shipments resulted from a multi-year project to relocate analytical, environmental monitoring, and other services from SRNL laboratory facilities to SRNL’s central location a few miles away. The move is expected to reduce costs due to those laboratory facilities being placed in surveillance and maintenance mode.
“Part of the modification project requires F/H Laboratories to ship nuclear materials from their location to SRNL’s main location,” Hubbard said. “Since that capability did not already exist, SRNL would have had to hire and train personnel and purchase a transport vehicle, which would have cost significant amounts of money and delayed SRNL operations. However, when HB Line personnel learned of the transportation needs, they stepped up to offer their help.”
Woodie Melton, director of SRNL Analytical Laboratories, commended the HB Line staff for helping SRNL.
“I want to thank the HB Line staff for their responsiveness in meeting SRNL’s critical need to get these materials transported,” Melton said. “Your lining up of resources and changing facility priorities is really appreciated.”
-Contributor: Lindsey MonBarren
Crews Mark 1 Million Miles of Safe Driving at Hanford Disposal Facility
Hanford Site workers with contractor CH2M HILL Plateau Remediation Company recently marked three years and 1 million miles of safe driving to support operations at the site’s disposal facility for low-level waste, the Environmental Restoration Disposal Facility.
CHPRC’s safe driving record goes back to August 2016, when the contractor took over operations of the site’s disposal facility for low-level waste after the previous contractor’s contract was completed.
Since ERDF began operating in 1996, the facility has received more than 18 million tons of contaminated soil, debris and solid waste from cleanup — most of it from areas along the Columbia River. The 107-acre facility — roughly the same area as 52 football fields — has supported the demolition of more than 800 facilities and remediation of more than 1,300 waste sites.
“ERDF has been a critical component of Hanford’s cleanup strategy for more than 20 years,” said Mark French, RL project and facilities division director. “The facility played a key role in moving most of the contaminated material away from the Columbia River, and it will continue to support our risk-reduction work on Hanford’s Central Plateau, where much of the nation’s plutonium was produced.”
The Environmental Restoration Disposal Facility supports cleanup efforts across the 580-square-mile Hanford Site. Since 1996, more than 18 million tons of contaminated soil, debris, and solid wastes from cleanup activities have been safely disposed of at the 107-acre facility.
Since the facility began operating in the 1990s, ERDF drivers have logged nearly 30 million miles in support of environmental cleanup efforts across the 580-square-mile Hanford Site.
“I couldn’t be more proud of our team,” said Tammy Hobbes, CHPRC vice president for the river risk management project. “Seeing the ERDF trucks moving across the site has become a daily reminder of the ongoing progress in Hanford cleanup.”
-Contributor: Lynn Tegeler
Oak Ridge Contractor Named One of America’s Safest Companies
UCOR Safety & Health Operations Manager Chris Thursby and UCOR Chief of Staff Ashley Saunders accept an award as one of America’s Safest Companies for their work conducting environmental cleanup in Oak Ridge.
OAK RIDGE, Tenn. – The magazine EHS Today has named EM’s Oak Ridge cleanup contractor UCOR one of America’s Safest Companies.
Each year, EHS Today recognizes companies with exceptional occupational safety, health, environmental, and risk management efforts. UCOR was one of 16 companies recently honored at the publication’s safety leadership conference in Dallas. EHS stands for environmental health and safety.
EHS Today identifies companies that meet criteria for America’s Safety Companies, such as support from leadership and management for environmental health and safety efforts, employee involvement in those efforts, innovative solutions to safety challenges, and good communication about the value of safety.
UCOR employees ensure safety as they conduct complex and challenging deactivation and decommissioning work at Oak Ridge.
Oak Ridge became the first site in the world to remove all of its gaseous diffusion uranium enrichment buildings, and next year, Oak Ridge is set to become the first site in the world to complete major cleanup of an entire uranium enrichment complex.
EHS Today’s recognition of UCOR’s safety program comes on the heels of DOE’s recertification of the company’s Star status. That’s the highest level of recognition for contractors through the Department’s Voluntary Protection Program (VPP). UCOR also recently received its third consecutive Star of Excellence Award from the VPP.
“We have 1,800 people working across ETTP, ORNL, and Y-12,” UCOR President and CEO Ken Rueter said. “ETTP, in particular, presented formidable cleanup challenges with the legacy buildings and structures with significant radioactive and chemical hazards. So, ‘Safety is a prerequisite to all we do’ quickly became our mantra.”