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At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

Case Study in Corporate Memory Recovery: Hanford Tank Farms Miscellaneous Underground Waste Storage Tanks - 15344

In addition to managing the 177 underground waste storage tanks containing 212,000 m3 (56 million gal) of radioactive waste at the U. S. Department of Energy’s Hanford Site 200 Area Tank Farms, Washington River Protection Solutions LLC is responsible for managing numerous small catch tanks and special surveillance facilities. These are collectively known as “MUSTs” - Miscellaneous Underground Storage Tanks. The MUSTs typically collected drainage and flushes during waste transfer system piping changes; special surveillance facilities supported Tank Farm processes including post-World War II uranium recovery and later fission product recovery from tank wastes. Most were removed from service following deactivation of the single-shell tank system in 1980 and stabilized by pumping the remaining liquids from them. The MUSTs were isolated by blanking connecting transfer lines and adding weatherproofing to prevent rainwater entry. Over the next 30 years MUST operating records were dispersed into large electronic databases or transferred to the National Archives Regional Center in Seattle, Washington. During 2014 an effort to reacquire the historical bases for the MUSTs’ published waste volumes was undertaken. Corporate Memory Recovery from a variety of record sources allowed waste volumes to be initially determined for 21 MUSTs, and waste volumes to be adjusted for 37 others. Precursors and symptoms of Corporate Memory Loss were identified in the context of MUST records recovery.

Washenfelder, D. J.↗
DOE OSTI2015

Case study in corporate memory recovery: Hanford tank farms miscellaneous underground waste storage tanks - 15344

In addition to managing the 177 underground waste storage tanks containing 212,000 m{sup 3} (56 million gal) of radioactive waste at the U. S. Department of Energy's Hanford Site 200 Area Tank Farms, Washington River Protection Solutions LLC is responsible for managing numerous small catch tanks and special surveillance facilities. These are collectively known as 'MUSTs' - Miscellaneous Underground Storage Tanks. The MUSTs typically collected drainage and flushes during waste transfer system piping changes; special surveillance facilities supported Tank Farm processes including post-World War II uranium recovery and later fission product recovery from tank wastes. Most were removed from service following deactivation of the single-shell tank system in 1980 and stabilized by pumping the remaining liquids from them. The MUSTs were isolated by blanking connecting transfer lines and adding weatherproofing to prevent rainwater entry. Over the next 30 years MUST operating records were dispersed into large electronic databases or transferred to the National Archives Regional Center in Seattle, Washington. During 2014 an effort to re-acquire the historical bases for the MUSTs' published waste volumes was undertaken. Corporate Memory Recovery from a variety of record sources allowed waste volumes to be initially determined for 21 MUSTs, and waste volumes to be adjusted for 37 others. Precursors and symptoms of Corporate Memory Loss were identified in the context of MUST records recovery. (authors)

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DOE OSTI2017

Video Camera Improvements to Support Hanford Tank Farms - 17141

Hanford Tank Farms consist of 177 underground storage tanks that contain 56 million gallons of radioactive waste. The current mission is to safely manage this waste in preparation to feed the Waste Treatment Plant. Fulfilling this mission includes inspecting each tank regularly to ensure tank integrity and support ongoing operations such as transferring waste from older single-shell tanks to the newer double-shell tanks. Video cameras derived from commercially available equipment have provided the ability to remotely see inside the tanks, reducing some of the challenges of fulfilling this mission. However, there are many challenges and limitations with the currently used video systems. Among some of the challenges are limited tank interior entry points for camera deployment, high radiation dose rates, limited equipment longevity in the environmental conditions, need for high resolution image quality, low light conditions, and in-tank obstructions. Washington River Protection Solutions (WRPS) has identified and tested new video systems that will effectively manage these challenges and increase capability, efficiency, and improve safety. The new camera systems are planned for deployment to support the next Single Shell Tank Retrieval Project in the A/AX tank Farm complex. (authors)

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DOE OSTI2012

Vehicle Radiation Monitoring Systems for Medical Waste Disposal - 12102

Hospitals often declare their waste as being 'non-radioactive'; however this material often has excessive levels of radiation caused either by an accident or lack of control. To ensure the best possible protection against the accidental receipt of radioactive materials and as a safety precaution for their employees, waste-handling companies have installed large-scale radiation portal monitors at their weigh scales or entry gates of the incinerator plant, waste transfer station, and/or landfill. Large-volume plastic scintillator-based systems can be used to monitor radiation levels at entry points to companies handling medical waste. The recent and intensive field tests together with the thousands of accumulated hours of actual real-life vehicle scanning have proven that the plastic scintillation based system is an appropriate radiation control instrument for waste management companies. The Real-Time background compensation algorithm is flexible with automatic adjustable coefficients that will response to rapidly changing environmental and weather conditions maintaining the preset alarm threshold levels. The Dose Rate correction algorithms further enhance the system's ability to meet the stringent requirements of the waste industries need for Dose Rate measurements. (authors)

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DOE OSTI2017

Performance Assessment for the Waste Management Area C at the Hanford Site in Southeast Washington - 17515

An initial performance assessment (PA) of Single-Shell Tank (SST) Waste Management Area C (WMA C) located at the U.S. Department of Energy's (DOE) Hanford Site in southeastern Washington has been completed to satisfy the requirements of the Hanford Federal Facility Agreement and Consent Order (HFFACO), as well as other Federal requirements and State-approved closure plans and permits. The WMA C PA assesses the fate, transport, and impacts of radionuclides within residual wastes left in tanks and ancillary equipment and facilities in their assumed closed configuration, and the subsequent risks to humans into the far future. This PA focused on radiological impacts has been developed to meet the requirements for a closure authorization under DOE O 435.1 that includes a waste incidental to reprocessing determination for residual wastes remaining in tanks, ancillary equipment, and facilities. PA results indicate that the performance objectives and measures for the all-pathways dose, the air pathway dose, the radon flux, and groundwater protection are met for both the 1,000-year compliance time period (2020 to 3020) and the post-compliance period (3020 to 12020). The peak dose for the all-pathways analysis in the 1,000-year compliance period is associated with the air pathway, with the peak dose of 4 x 10{sup -5} mSv/yr dominated by tritium resulting from upward gaseous diffusive flux from the residual waste. The peak dose within the sensitivity/uncertainty analysis time period (1,000 to 10,000 years after closure) occurs at about 1,500 years after closure, and results primarily from a peak in {sup 99}Tc groundwater concentration at 100 m down-gradient of the facility. The peak total dose within the sensitivity/uncertainty analysis time period is 0.001 mSv/yr. For all of the sensitivity analyses and uncertainty analyses evaluated, the disposal system also met the performance objectives. In the uncertainty analysis performed with the system level model based on GoldSim{sup C}, the highest calculated groundwater dose in the compliance period was about 7 x 10{sup -4} mSv/yr, and the highest calculated peak dose in the sensitivity/uncertainty analysis period was 0.025 mSv/yr.Doses associated with hypothetical inadvertent human intrusion were calculated for all sources in WMA C and compared to the acute and chronic performance measures in DOE O 435.1. The calculated doses for acute and chronic exposure scenario from potential intrusion into a waste transfer pipeline remain below the DOE O 435.1 performance measure for the time period evaluated beyond 100 years after closure. Acute exposure from drilling into the waste yielded a dose of about 0.36 mSv after the assumed 100-year institutional control period, well below the 5 mSv performance measure for acute exposure. Chronic exposure to waste from drill cuttings in a rural pasture scenario resulted in a dose of about 0.08 mSv/yr after the assumed 100-year institutional control period, well below the 1 mSv/yr performance measure for chronic exposure. (authors)

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DOE OSTI2024

Analysis of Tank 38H (HTF-38-23-95, -96) and Tank 43H (HTF-43-23-93, -94) Samples for Support of the Enrichment Control and Corrosion Control Programs

Savannah River National Laboratory analyzed samples from Tank 38H and Tank 43H to support Enrichment Control Program (ECP) and Corrosion Control Program (CCP). The results indicate the concentrations of most soluble species in the Tank 38H surface sample increased significantly from the previous Tank 38H surface sample. The current Tank 38H subsurface sample shows similar Na, free hydroxide, and anions versus the previous subsurface sample. However, the 38H subsurface sample shows higher concentrations of Al, Ca, Fe, Mn, and Si vs. the previous Tank 38H subsurface sample. The current Tank 38H subsurface sample contained visible sludge solids in excess of the previous sample based on visual appearance. Weight percent solids measurements indicate presence of 3.0 ± 0.1 wt.% insoluble solids in the Tank 38H subsurface sample. The significant differences in the concentrations of major components between the Tank 38H surface and subsurface samples indicate significant stratification of solution species between these two locations within the Tank 38H. Savannah River Mission Completion (SRMC) personnel indicated that there were no tank-to-tank transfers into Tank 38H since early January 2023 and the 2H (16H) Evaporator was shut down on 3/26/2023 and has not operated since that time. There have been many pumped non-waste transfers of water from the H-Area diversion box 7 (HDB-7) sump into Tank 38 since the 3/26/2023 date.

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DOE OSTI2018

ROV used in Sludge Retrieval and Treatment Project - 18575

The Orano-operated waste treatment site at La Hague, France, has treated large quantities of nuclear waste through-out its many decades of operation. During a period of over twenty years, a significant amount of the radioactive sludge resulting from the liquid waste treatment processes was placed into a set of adjoining tanks, called the STE2 silos. Now that those tanks are reaching capacity, a project has begun to retrieve this waste, transfer it to another location for homogenisation and characterization, and to then send it to another facility for conditioning and long-term storage. Because of the conditions inside and around these tanks, the waste retrieval process has many limitations. For example, the high radiation levels require that the retrieval be done efficiently, with a high removal rate and that operation be done remotely. The sludge retrieval tool will be operated and navigated while hidden inside the tank, under a significant amount of supernatant liquid, but needs to be accessible for maintenance and modifications and able to be transferred from one tank to the next. Additionally, the highly viscous consistency of the sludge requires special suction capabilities. All of these conditions need to be met, by a system that fits into the tanks' 900 mm (<3 ft) access ports. After almost three years of profound engineering, construction and testing efforts, a final design has been approved. The tool consists of a 250 kg (∼550 lb), remotely-operated vehicle (ROV) with an Archimedes-type screw attachment. It is delivered into and retrieved from the tank through a shielded glovebox that allows for maintenance and exchange of attachments. Sludge is sucked through a rotating screw and out a second tank opening with a consideration for limiting external water usage. To locate and navigate the tool, cameras detect LEDs attached to the ROV's buoys, and then calculate the ROV's position and orientation. With preliminary design and testing of the prototype complete, the project is preparing to award the ROV manufacturing contract and finalize the design of auxiliary systems, such as the rinsing and maintenance processes and localization instrumentation. After extensive final testing, the gloveboxes will be placed over the tanks in mid-2020, with entry into the first tank expected in April 2024. The ideas and experiences Orano is currently gathering during this effort will be of interest to laboratories and facilities that will soon be retrieving waste sludge from their aging storage tanks. (authors)

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DOE OSTI2020

System and method for recovering waste heat

A power generation system having a combustion engine with a Rankine bottoming cycle, the system including a first flow path for a process fluid and a second flow path for a working fluid, and a heat exchanger arranged along both the first and the second flow paths to transfer waste heat from the process fluid to the working fluid. The heat exchanger includes a first flow conduit being bounded by a first wall section and configured to convey the process fluid, a second flow conduit to convey the working fluid, the second flow conduit being bounded by a second wall section spaced apart from the first wall section to define a gap therebetween, and a thermally conductive structure arranged within the gap and joined to the first and second wall sections to transfer heat therebetween, the gap being fluidly isolated from both the process fluid and the working fluid.

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2025

Slow Strain Rate Testing of A537 Tank Wall Material

At Savannah River Site (SRS), High-Level Waste is stored in below-grade carbon steel tanks. This waste in part consists of sludge, salt cake, and/or supernate. Preparation of this waste for future processing involves dissolution of the salt cake layer. The salt dissolution process can create conditions that leave the carbon steel tanks susceptible to localized corrosion. The salt to be dissolved contains high concentrations of nitrate, that once released, create an environment that may be conducive to pitting corrosion and/or stress corrosion cracking (SCC) of carbon steel. The salt dissolution process also liberates interstitial liquid trapped between the salt crystals. This liquid is initially high in nitrite and hydroxide concentration. High pH and greater ratios of nitrite to nitrate act as inhibitors to minimize corrosion of carbon steel in high nitrate environments. However, as dissolution proceeds, the concentration of nitrate will increase, while the hydroxide and nitrite concentration of the interstitial liquid will deplete and become insufficient to prevent the onset of corrosion attack. Tank blending and the addition of inhibitors are used to ensure adequate concentrations of hydroxide and nitrite. However, this is not desirable during salt dissolution as it can reduce process efficiency and increase the amount of waste that needs processing. This testing program was designed to examine the risk of SCC associated with utilizing the pitting factor (PF) and nitrite/nitrate (NO 2 - /NO 3 - ) ratio limits for handling dissolved salt solutions at an elevated temperature in the carbon steel waste tanks. The previously identified limits are a PF of 1.2 and an NO 2 - /NO 3 - ratio of 0.15. The results indicate that as long as the NO 2 - /NO 3 - ratio exceeds 0.1 and the PF is above approximately 0.8, there is a discernible safety margin between the open circuit potential (OCP) and the critical cracking potential (CCP) observed during applied potential testing. However, this margin, defined by the difference between the OCP and CCP, is relatively narrow, ranging from 0.1 to 0.25 volts. This small margin raises concerns about potential shifts in OCP during waste retrieval operations, which could inadvertently increase the risk of SCC if the OCP approaches or exceeds the CCP. These results confirm that dissolved salt solutions provide a potent chemistry that, under certain conditions, makes carbon steel susceptible to SCC. The next question to consider is the influence these results have on decisions for storage and retrieval of waste from the tanks. For Type III/IIIA waste tanks, the risk of SCC remains very low. First, and most importantly, the post-weld stress relief of the tanks has reduced the residual stress near the welds. Thus, without the stress component, SCC risk is minimized. The material of construction (A537 Carbon steel) for the Type III/IIIA tanks is superior to the steel in its resistance to SCC than the steel that was utilized for the Type I, II, and IV tanks (A285 carbon steel). From a chemistry control standpoint for a Type III/IIIA tank directly involved with handling dissolved salt solutions, the PF and NO 2 - /NO 3 - ratio limits may be utilized wherein chemistry control provides an extra layer of defense against SCC. Chemistry control for a Type III/IIIA tank minimizes the risk for a tank that may receive the dissolved salt solution, particularly if that tank is a Type I, II, or IV waste tank. On the other hand, if the dissolved salt solution is handled by a Type I, II, or IV waste tank the risk of SCC is real. The potent chemistry, absence of stress relief, and inferior material result in a condition that is conducive to cracking. Efforts should be made to either avoid transferring waste that may not meet the PF and NO 2 - /NO 3 - ratio criteria to one of these tanks or if it is unavoidable, take measures to minimize the consequences of a leak. As shown by these tests, even if the PF and NO 2 - /NO 3 - ratio criteria are met, there is a risk that the tank potential may be disturbed in the positive direction and the risk of SCC increase.

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DOE OSTI2016

Detection and Mitigation of Hanford Site Radioactive Waste Tank Surface Water Intrusion - 16396

The last single-shell underground radioactive waste storage tanks at the U.S. Department of Energy's Hanford Site, near Richland, WA, were removed from service in November, 1980. At that time the single-shell tanks contained 153,300 m{sup 3} (40.5 million gallons) of waste, including 34,400 m{sup 3} (9.1 million gallons) of liquids. Subsequently the Interim Stabilization Program and Waste Retrieval/Closure Project have removed 24,600 m{sup 3} (6.5 million gallons) of liquid from the tanks to reduce the potential for leakage to the environment. After interim stabilization, each tank was isolated by cutting and capping waste transfer lines, filling drains with grout, and covering likely surface water entry points. The minimum expected lifetime for the isolation features was 20 years, consistent with planned retrieval of all single-shell tank wastes by 2018. Since then the retrieval completion date has been extended. In 2011 the Tank Operating Contractor began a systematic review of the aging isolation barriers to determine if surface water was entering the single-shell tanks. This paper summarizes the results of the 2011 - 2015 activities including single-shell tank inspection results, methodologies used to identify intrusions and waste leaks masked by intrusion, and eventual deployment of a prototype forced ventilation exhauster in 2015 to evaporate water intrusion pools on the waste surface. Further efforts to limit water intrusion, including deployment of surface barriers, are discussed. (authors)

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DOE OSTI2017

Direct-Feed Low-Activity Waste: First Feed Flowsheet - 17108

In support of hot commissioning of the Low-Activity Waste Pretreatment System (LAWPS) and the Hanford Tank Waste Treatment and Immobilization Plant (WTP) LAW facility, the First Feed Flowsheet was initiated to project process stream characteristics and unit operation performance. The First Feed Flowsheet uses flowsheet models to simulate the preparation of the first feed campaign in Tank Farms and the subsequent feeding of the waste to the Low-Activity Waste Pretreatment System (LAWPS) and the WTP LAW facility. Three different models were used: a chemistry model of waste transfers developed in the Environmental Simulation Program (ESP), Washington River Protection Solutions' (WRPS') dynamic gPROMS{sup TM} LAWPS flowsheet model, and WTP's Dynamic G2 flowsheet model. Information from all three models showed favorable comparison of the waste feeds and secondary liquid wastes against waste compatibility assessment and waste acceptance criteria at multiple stages in the flowsheet. (authors)

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DOE OSTI2013

A Comprehensive Solution for Managing TRU and LLW From Generation to Final Disposition - 13205

A LANL multi-disciplinary team faced the challenge of building and delivering a waste information system capable of managing radioactive, hazardous, and industrial waste from cradle to grave. The result is the Waste Compliance and Tracking System (WCATS) a flexible, adaptive system that has allowed LANL to consolidate its legacy applications into one system, and leverage the advantages of managing all waste types within a single scalable enterprise application. Key functionality required for robust waste operations, include: waste characterization, waste identification, transportation, inventory management, waste processing, and disposal. In order to maintain data quality, field operations such as waste identification, surveillance checklists, wall-to-wall inventory assessments, waste transfers, shipment pickup and receipt, and simple consolidation operations are captured by the operator or technician using mobile computers. Work flow is managed via end-user defined work paths, to ensure that unit operations are performed in the correct order. Regulatory compliance reports and algorithms are provided to support typical U.S. EPA, DOT, NRC, and DOE requirements, including the EPA hazardous waste manifest, NRC LLW manifest, DOE nuclear material at risk, RCRA TSDF inventory rules, and so forth. The WCATS application has allowed LANL to migrate and consolidate its disparate legacy applications. The design and implementation is generalized so that facility owners can customize the user interface, setup facilities and unit operations (i.e., treatment, storage, disposal, characterization, and administrative), define inventory compliance rules, and establish custom work flow requirements. (authors)

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DOE OSTI2018

Integrated Salt Waste Processing at the Savannah River Site - 18549

An intricate shoring system to provide protection to the workers and to critical components in the area was designed and installed. Designing and installing shoring systems is commonplace around the world, but installing it adjacent to high-level radioactive waste transfer lines nearly twenty feet in depth with tolerances within one-one thousandths of an inch required a more robust design. Upon completion, approximately 671 square meters (or 7,225 square feet) of sheet piling was installed without issue. (authors)

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DOE OSTI2024

FIU Project1: Chemical Process Alternatives for Radioactive Waste [Slides]

"The U.S. DOE Hanford Site has the largest number of high-level waste (HLW) storage tanks and the largest volume of HLW in the United States. The safe storage, retrieval, treatment, and disposal of approximately 53 million gallons of highly toxic, high-level radioactive waste stored in Hanford’s 177 underground tanks are a national priority. Retrieval and treatment of waste from these tanks pose a considerable challenge. Florida International University has been conducting research on several promising alternative processes and technologies that can be applied to address several technology gaps in the current waste retrieval and conditioning plans. Specifically, FIU has been involved in: the evaluation of non-metallic materials in the waste transfer system, evaluation of alternative HLW instrumentation for in-tank applications and the development of technologies to assist in the inspection of tank bottoms at Hanford."

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DOE OSTI2020

Implementing Mixed Reality Tools to Support Mission Delivery at Hanford - 20520

Mission Support Alliance's (MSA) Public Works and Information Systems organizations have been working with Microsoft Corporation to develop and implement mixed reality operational solutions using their HoloLens technology. This collaborative effort is intended to drive innovative solutions and significantly improve MSA's efficiency in performing work at the Hanford Site. HoloLens, a mixed reality tool, is a commercial off-the-shelf technology that combines a head-mounted viewing screen with applications to help people and organizations learn, communicate, and collaborate more effectively through the use of mixed reality. https://microsoft.com/en-us/hololens MSA's initial pilot successfully demonstrated its ability to use mixed reality utilizing HoloLens' advanced features in a variety of ways, illustrating the potential efficiency gains previously stated as goals of this pilot. These achievements include the development of proprietary technology that allows synchronization between a HoloLens device and a mobile device or alternate global positioning system (GPS) device. This synchronization enables the HoloLens device to access real time GPS location data anywhere on the Hanford Site. This real time location data, combined with MSA's improved Hanford Geographical Information System (GIS) data, enables the mixed reality pilot application to identify underground utility systems as well as related utility attributes. This ability will aid utility workers in several areas, including excavation activities, the placement of large cranes, identifying interactions and conflicts with future underground utility placements and, eventually, recognizing and de-conflicting tank waste transfer system valve alignments. The HoloLens mixed reality application is also able to provide full or small scale holographic images of a facility's digital twin. This feature will allow MSA's Water and Sewer Utilities team to train and validate procedures associated with the new water treatment facility virtually, before it is constructed. This reduces the amount of time it takes to complete the training and procedure validation, and accelerates the overall construction schedule. (authors)

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DOE OSTI2025

FY24 Task 5: Leachate Disposition

Directly feeding sludge solids to the high-level waste (HLW) Waste Treatment Plant represents an alternative flowsheet seeking to initiate sludge processing as soon as possible. Key processing functions previously captured during baseline pretreatment operations include leaching and washing prior to solids concentration. These operations should be considered in the potential direct feed flowsheets to maximize waste feed loading, minimize HLW volume, and mitigate corrosion challenges associated with vitrification of high phosphate and fluoride concentrations. Additionally, single-shell tank (SST) retrievals and waste transfers to double-shell tanks (DSTs) in a direct feed flowsheet would likely also benefit from some level of leaching, washing, and solids concentration in order to reduce DST space and mission duration. These operations could occur in a new facility or potentially in available DSTs. If washing and leaching are utilized, an effective disposition pathway for the wash water and leachate solutions are needed. Three target species that benefit significantly from leaching and washing are phosphate, fluoride and aluminum. Phosphate (PO 4 3- ) and fluoride (F - ) can contribute substantially to the amount of carrier fluid needed for dissolution, and the resulting volume of liquid generated. Disposition of this retrieval solution should be evaluated in order to prevent crystallization of these anions throughout system processing. Since there is a high probability that any retrieval solutions will be at or near their PO 4 3- and F - solubility limits, evaporation or blending with a high Na supernate (>3.5 M) is not recommended for the wash water streams without a method to remove precipitants prior to solution disposal. Additionally, aluminum present in the southeast quadrant of the Hanford site represents roughly 60% of the waste solids in the initial processing tanks. These aluminum solids are in the form of gibbsite (Al(OH) 3 ) and can pose significant challenges for processing due to the fast-settling times and high solids loading associated with these materials. Easily remediated by caustic addition to the solids, these wash solutions could be processed through crystalline silicotitanate (CST) ion exchange columns to prepare the supernate solutions for disposition. The current target for feed conditions to the Low Activity Waste (LAW) melter are waste streams that contain nominally 5-6 M Na. Fractions within the tanks contain upwards of 0.2 M phosphate and fluoride in solution at 3.5 M Na. Concentrating these solutions above 5 M Na would result in an exceedance of the solubility limits, and potential for uncontrolled precipitation of the phosphate and fluoride crystal material. The resulting crystalline salt material is typically sodium fluoride phosphate, also referred to as natrophosphate (Na 7 FPO 4 ·19H 2 O). Salt phases are of importance in tank waste due to their chemical reactivity, which can result in precipitation, dissolution, or transformation, impacting any downstream processes (Bolling et al. 2020, Russell, Snow, and Peterson 2010). Salt generation and precipitation could pose challenges by causing system plugging and melter corrosion if left in the supernate stream, or limit sodium molarity of the supernate that would be accepted without incident in waste operations. To understand the impact of this salt generation, the crystallization of natrophosphate in multiple simulant feed matrices was studied to understand the implications of various tank waste supernate chemistries. Three matrices were examined: high PO 4 3- /low F - , low PO 4 3- /high F - , and an average matrix. Subsequent testing was performed with the average matrix with the inclusion of CsNO 3 , and a final run with the average matrix including CsNO 3 and a 137 Cs spike for tracer purposes.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Accelerating Hanford Site Cleanup through Operations Research Modeling - 20238

The Hanford Site cleanup effort will require the integration of dozens of unique facilities and processes, many of which will be first-of-a-kind in implementation and design. Each facility will be governed by its own set of operating logic, configured with a unique array of unit operations, and subject to a set of constraints that will affect its behavior. The collection of facilities have multiple points of interface, making the operations of any one facility potentially significant to the operations of other up- or downstream processes. It is therefore highly desirable to accurately predict these operations, as it allows for Site officials to identify and preempt bottlenecks and vulnerabilities before they unexpectedly inhibit the cleanup mission. With the quantity and complexity of the processes that will be on Site, building a pen-and-paper or even a spreadsheet-assisted model of the cleanup mission quickly becomes overwhelming in scope and inaccurate in execution. The Engineering organization for the Site's Tank Operations Contract (TOC) has therefore implemented the use of operations research (OR) modeling to simulate and predict future operations of Site facilities. These models are created using a discrete event simulation tool that allows for the development of detailed, versatile, and robust models. Not only can these models account for complex logical behaviors, but they can also simulate process details down to the level of vessel sizing, labor utilization, equipment reliability, and resource availability. To date, the TOC has developed OR models for several facilities on Site, including for single-shell tank (SST) farms, double-shell tank (DST) farms, the Effluent Treatment Facility (ETF), and the waste transfer system. These models have focused on identifying bottlenecks and operational constraints, and have been used to quantify the effects of implementing process changes. This latter point is particularly valuable, as it allows for several alternatives to be studied in a virtual setting before committing resources to making a change in the field. The decision to develop OR models has gained tremendous support from the Site's stakeholders and the U.S. Department of Energy (DOE) management, and has prompted the use of the tool to support additional internal and external initiatives. Recently, an initiative was proposed to use the models to help identify and provide quantitative backing for risks and opportunities for the TOC. This application of OR could not only help inform how the TOC manages its risks (e.g. quantities and types of spare parts), but could also help drive process improvements whose benefits might otherwise be hard to quantify. The models have also been used to drive the TOC's cloud computing, artificial intelligence (AI), and machine learning (ML) initiatives. These initiatives will not only improve the ability of the TOC to more rapidly respond to the needs of its customers, but it will also aid in the ability of the TOC to analyze and improve the processes it studies. Partnership with two external software development and consulting companies (Lanner and Ynformed) has furthered not only the application of AI and ML within the TOC, but has also spurred the development of new/improved software tools and platforms used by the companies. These partnerships have proven to be mutually beneficial and productive, and have set a precedent for the types of gains that can be made by exploring such options. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Implementing a Low-Activity Waste Direct Feed Capability in the Waste Treatment and Immobilization Plant Project - 15594

The current design of the Waste Treatment and Immobilization Plant (WTP) requires that all waste be processed through the Pretreatment (PT) Facility. The U.S. Department of Energy (DOE) has developed a strategic, phased approach to completing the WTP Project, beginning with feeding some liquid waste from the tank farms to the Low-Activity Waste (LAW) Facility, bypassing the PT Facility. To accomplish this, the DOE Office of River Protection (ORP) will construct a new capability outside WTP to remove cesium and solids from the liquid portion of the tank waste before transferring that waste to the LAW Facility. This new capability, referred to as the Low-Activity Waste Pretreatment System, is outside WTP and not included in the project's scope. The primary driver for the Direct-Feed LAW (DFLAW) approach is to enable commissioning of the LAW Facility for low-activity waste processing before the PT and High-Level Waste Facilities are complete and operational. As such, the functions intended to be provided to the LAW Facility by the PT Facility and the common functionality with the High-Level Waste Facility must be refined and modified. The DFLAW approach will provide necessary systems and facilities to replace these enabling PT Facility functions until the PT Facility is completed and commissioned. In February 2014, ORP requested the WTP contractor to develop separate contract modification proposals for completing: (1) the LAW Facility, Balance of Facilities, and Analytical Laboratory work scope in the current contract through hot commissioning in a manner to accommodate a phased start of the WTP mission; and (2) initial planning and design for incorporating a permanent capability to accommodate DFLAW in the WTP. (authors)

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