TANK SPACE OPTIONS REPORT

A demonstration of As Low As Reasonably Achievable Control Technology (ALARACT) was performed for the existing Double Shell Tank (DST) farm primary ventilation systems in support of the Single Shell Tanks (SSTs) Interim Stabilization Project. The primary ventilation systems evaluated in this ALARACT are located at the 241-AW, AN, AP, and SY tank farms. Of these farms, only the AP and SY farms are scheduled to receive SST waste prior to new ventilation systems being installed at the farms. As a result, full evaluations were performed for the 241-AP and SY systems, whereas only partial evaluations were performed for the 241-AN and AW systems. The full evaluation included the evaluation of the stack sampling system, whereas the partial evaluation did not. Also, 241-AY and AZ are not scheduled to receive SST waste so they were both excluded completely from the evaluation. This ALARACT demonstration evaluated the ability of the abatement and control technologies in the DST ventilation systems identified above to function during SST waste transfers as part of the SST Interim Stabilization Project. Where available, field data (waste temperatures) gathered during actual saltwell pumping activities, were used to support this demonstration. Also used were other process data and equipment capacities associated with the system evaluation. Where actual field data were not available, conservative assumptions, based upon process knowledge and standard engineering calculation methodologies, were used. The DST ventilation systems were also evaluated for compliance against the technology standards identified in Washington Administrative Code (WAC) 246-247, Radioactive Air Emissions, as well as other governing codes and standards.

This document has two purposes: {sm_bullet} Describe how data generated by High Resolution REsistivity (HRR) leak detection (LD) systems deployed during single-shell tank (SST) waste retrieval operations are processed and evaluated. {sm_bullet} Provide the basic review requirements for HRR data when Hrr is deployed as a leak detection method during SST waste retrievals.

This document describes the baseline single-shell tank (SST) waste retrieval sequence for the River Protection Project (RPP) updated for Fiscal Year 2000. The SST retrieval sequence identifies the proposed retrieval order (sequence), the tank selection and prioritization rationale, and planned retrieval dates for Hanford SSTs. In addition, the tank selection criteria and reference retrieval method for this sequence are discussed.

The Hanford Site is a 560-square-mile (1,450-km2) complex established by the U.S. government in 1943 to produce plutonium for nuclear weapons, ultimately bringing an end to World War II. Plutonium production activities continued after the war through 1991, at which point the site’s mission changed from plutonium production to environmental cleanup and restoration. Production activities at the site resulted in a broad range of contaminated materials and facilities, including 57 million gallons of high-level (i.e., highly radioactive) nuclear waste in liquid and solid forms. The high-level waste was stored as it was created, first in single-shell tanks built between 1943 and 1964, then in more robust double-shell tanks constructed between 1968 and 1986. Due to waste leakage in a small number of single-shell tanks and the potential for additional single-shell tank failures, all single-shell tanks were removed from service by 1980. All pumpable liquid has been transferred to sound double-shell tanks. The double-shell tanks have either exceeded or are expected to exceed their design life, and are managed under a comprehensive integrity management program. Key features of the program include the application and optimization of a waste chemistry specification designed to minimize corrosion in the double-shell tanks, laboratory studies, and the installation of double-shell tank corrosion monitoring systems to improve the understanding of waste corrosiveness, the development and application of an extensive non-destructive examination program to detect excessive corrosion or other forms of double-shell tank degradation should they occur, and the development and application of a comprehensive structural analysis program. Together, these programs help to ensure the continued availability of the site’s double-shell tanks for the balance of the cleanup mission.

During most of the year, it is assumed that the vapor in the 177 radioactive waste tanks on the Hanford Project site contain a uniform mixture of gases. Several of these waste tanks (currently twenty five, 6 Double Shell Tanks and 19 Single Shell Tanks) were identified as having the potential for the buildup of gases to a flammable level. An active ventilation system in the Double Shell Tanks and a passive ventilation system in the Single Shell Tanks provides a method of expelling gases from the tanks. A gas release from a tank causes a temporary rise in the tank pressure, and a potential for increased concentration of hydrogen gas in the vapor space. The gas is released via the ventilation systems until a uniform gas mixture in the vapor space is once again achieved. This document describes the design of the Standard-B Hydrogen Monitoring System, (SHMS) and its components as it differs from the original SHMS. The differences are derived from changes made to improve the system performance but not implemented in all the installed enclosures.

This document is the master work plan for the Resource Conservation and Recovery Act of 1976 (RCRA) Corrective Action Program (RCAP) for single-shell tank (SST) farms at the US. Department of Energy's (DOE'S) Hanford Site. The DOE Office of River Protection (ORP) initiated the RCAP to address the impacts of past and potential future tank waste releases to the environment. This work plan defines RCAP activities for the four SST waste management areas (WMAs) at which releases have contaminated groundwater. Recognizing the potential need for future RCAP activities beyond those specified in this master work plan, DOE has designated the currently planned activities as ''Phase 1.'' If a second phase of activities is needed for the WMAs addressed in Phase 1, or if releases are detected at other SST WMAs, this master work plan will be updated accordingly.

One of the main functions of the River Protection Project is to store the Hanford Site tank waste until the Waste Treatment Plant (WTP) is ready to receive and process the waste. Waste from the older single-shell tanks is being transferred to the newer double-shell tanks (DSTs). Therefore, the integrity of the DSTs must be maintained until the waste from all tanks has been retrieved and transferred to the WTP. To help maintain the integrity of the DSTs over the life of the project, specific chemistry limits have been established to control corrosion of the DSTs. These waste chemistry limits are presented in the Technical Safety Requirements (TSR) document HNF-SD-WM-TSR-006, Sec. 5.15, Rev 25 (CHG 2001). In order to control the chemistry in the DSTs, the Chemistry Control Program will require analyses of the tank waste. This document describes the Data Quality Objective (DQO) process undertaken to ensure appropriate data will be collected to control the waste chemistry in the DSTs.

This mission analysis report for the Hanford Tanks Initiative (HTI) supports the Hanford Site`s Single-Shell Tank (SST) Waste Retrieval Program in its commitment to remove waste from the SSTs for treatment and final closure of the tanks. The results of the HTI will support the US Department of Energy`s (DOE) privatization of retrieval efforts. This report addresses the HTI problem statement: Alternative technologies to past practice sluicing (PPS) have not yet been demonstrated to remove the hard heel from a sluiced tank or to remove waste from a leaking SST. Nor have performance-based criteria for cleanout and closure been demonstrated to the degree necessary to validate them as technically and economically achievable. This report also defines the mission statement and mission boundaries; the known interfaces, both programmatic and project; the mission level requirements; the test and evaluation methodology; and measures of success.

This report summarizes the predictive methods used to ensure that waste transfer operations in Hanford waste tanks do not create waste configurations that lead to unsafe gas release events. The gas release behavior of the waste in existing double-shell tanks has been well characterized, and the flammable gas safety issues associated with safe storage of waste in the current configuration are being formally resolved. However, waste is also being transferred between double-shell tanks and from single-shell tanks into double-shell tanks by saltwell pumping and sluicing that create new wastes and waste configurations that have not been studied as well. Additionally, planning is underway for various waste transfer scenarios to support waste feed delivery to the proposed vitrification plant. It is critical that such waste transfers do not create waste conditions with the potential for dangerous gas release events.

The presence of organic chemicals regulated under the Resource Conservation and Recovery Act (RCRA) Land Disposal Restrictions (LDR) adds complexity to treating and disposing of the low activity fraction of Hanford tank waste if a low temperature treatment method such as grouting is used (SRNL-STI-2020-00228). The complexity arises from the fact that the baseline vitrification method is considered by the Washington State Department of Ecology (Ecology) as providing adequate thermal treatment for organics; a status not automatically extended to a lowtemperature process, such as solidifying the waste in a cementitious waste form. In addition, the Environmental Protection Agency (EPA) LDR program is intended to ensure that wastes are properly treated prior to disposal. Proper treatment makes hazardous waste less harmful to groundwater by reducing the mobility and/or toxicity of the hazardous constituents in the waste. EPA guidance indicates that stabilization/solidification of waste for organics could be considered impermissible dilution under the LDR dilution prohibition. In addition, waste storage activities at Hanford have required transferring and blending waste within the tank system and these activities have potentially altered the concentrations of the hazardous constituents. The LDR dilution prohibition found in 40 Code of Federal Regulations (CFR) 268.3 states that “… no generator, transporter, handler, or owner or operator of a treatment, storage, or disposal facility shall in any way dilute a restricted waste or the residual from treatment of a restricted waste as a substitute for adequate treatment …”. Hence, if LAW is to be treated using low temperature stabilization (such as cementation), then it is important to demonstrate both how past storage activities have contributed to the removal (by vacuum evaporation), or destruction (by in situ decomposition) of the LDR organics and how future retrieval and waste feed preparation will contribute to their removal (by filtration and ion exchange). Demonstrating these processes helps validate that cementation without additional organic treatment does not necessarily represent impermissible dilution. To aid in implementing cementitious solidification of Low Activity Waste (LAW), WRPS has been developing a regulatory and processing LDR treatment variance strategy termed “Sampleand-Send” that relies, in part, on demonstrating that in situ decomposition reactions along with historic evaporation of tank waste has destroyed or removed most of the LDR organics possibly associated with Hanford Tank Waste (SRNL-STI-2020-00582, SRNL-STI-2021-00453, SRNL-STI-2022-00391). Under the Sample-and-Send concept, Hanford tank waste would be retrieved, processed through a Tank-Side Cesium Removal-like system, and staged as a candidate feed that would then be sampled to confirm the waste acceptance criteria is met for solidification in an LAW cementitious treatment facility. If it can be shown that LDR organics are at concentrations below the waste acceptance criteria (WAC) for cementitious stabilization and have been sufficiently removed (by historic evaporation or by filtration and ion exchange during Cs removal), destroyed (by historic in situ decomposition), or are not soluble in LAW above the WAC then additional organic treatment is not needed prior to creating a cementitious final waste form and the concept of Sample-and-Send would be proposed to establish a non-rulemaking site-specific treatment variance using the specified method of treatment “STABL” to remove sampling requirements of the waste form after treatment. Waste not meeting the WAC could either be routed to the Hanford Waste Treatment and Immobilization Plant for LAW vitrification, or further processed by evaporation or chemical oxidation before solidifying in a cementitious waste form. A key component in implementing the Sample-and-Send strategy is identifying which of the 207 LDR organic compounds associated with the RCRA Part A permit application waste codes for the Double Shell Tanks (DSTs) and Single Shell Tanks (SSTs) and any applicable Underlying Hazardous Constituents (UHCs) from 40 CFR 268.48 should be considered as potentially present and thus subject to regulation. In addition, it is also necessary to understand the solubility volatility, and reactivity of these compounds in LAW to identify which of the potentially present LDR organic compounds are not soluble above regulatory levels or are likely to have been removed by historic evaporation or destroyed by in situ decomposition reactions. If there are potentially present LDR organic compounds that have not been removed or destroyed and are soluble above regulatorily significant concentrations then a treatability variance may be needed for these species to eliminate any concerns pertaining to impermissible dilution. The spreadsheet accompanying this calculation report contains the data and logic computations needed to screen the list of 207 LDR organics associated with Hanford tank waste to identify those potentially present and to indicate which compounds may need to be included in a treatability variance.

This report was initially designed to provide a comprehensive review of potential leak detection technologies (LDTs). To this end, the report would contain several sections outlining the selection process. The purpose was twofold:(l) the reader would have a clear understanding of why specific technologies were recommended or not recommended, and (2) the reader could apply the same process in the future as new LDTs become available. Curtailment of project scope has prevented the development of the requisite judging criteria. The report has been modified accordingly. Section 2 of this report presents the baseline and guiding assumptions that were used to judge the LDTs. These assumptions include the environment where the technologies would be employed, the potential leak detection targets, and anticipated leak mechanisms. Section 3 presents a brief review of the methods used to arrive at the recommended LDTs. It also includes a description of the different technology families considered. Section 4 presents the recommended LDTs along with detailed descriptions of each that include sensitivities, operating parameters, and costs.

The majority of defense wastes generated from reprocessing spent N- Reactor fuel at Hanford are stored in underground Double-shell Tanks (DST) and in older Single-Shell Tanks (SST) in the form of liquids, slurries, sludges, and salt cakes. The tank waste remediation System (TWRS) Program has the responsibility of safely managing and immobilizing these tank wastes for disposal. This report discusses three principle topics: the need for and basis for selecting target or reference LLW simulants, tanks waste analyses and simulants that have been defined, developed, and used for the GDP and activities in support of preparing and characterizing simulants for the current LLW vitrification project. The procedures and the data that were generated to characterized the LLW vitrification simulants were reported and are presented in this report. The final section of this report addresses the applicability of the data to the current program and presents recommendations for additional data needs including characterization and simulant compositional variability studies.

The U.S. Department of Energy's (DOE) Office of River Protection (ORP) is responsible for the retrieval, treatment, immobilization, and disposal of Hanford's tank waste. Currently there are approximately 56 million gallons of highly radioactive mixed wastes awaiting treatment. A key aspect of the River Protection Project (RPP) cleanup mission is to construct and operate the Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the RPP mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA), i.e. December 31, 2047. Therefore, Supplemental Treatment is required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. The Supplemental Treatment chosen will immobilize that portion of the retrieved LAW that is not sent to the WTP's LAW Vitrification facility into a solidified waste form. The solidified waste will then be disposed on the Hanford site in the Integrated Disposal Facility (IDF). In addition, the WTP LAW Vitrification facility off-gas condensate known as WTP Secondary Waste (WTP-SW) will be generated and enriched in volatile components such as Cs-137, I-129, Tc-99, Cl, F, and SO{sub 4} that volatilize at the vitrification temperature of 1150 C in the absence of a continuous cold cap. The current waste disposal path for the WTP-SW is to recycle it to the supplemental LAW treatment to avoid a large steady state accumulation in the pretreatment-vitrification loop. Fluidized Bed Steam Reforming (FBSR) offers a moderate temperature (700-750 C) continuous method by which LAW and/or WTP-SW wastes can be processed irrespective of whether they contain organics, nitrates, sulfates/sulfides, chlorides, fluorides, volatile radionuclides or other aqueous components. The FBSR technology can process these wastes into a crystalline ceramic (mineral) waste form. The mineral waste form that is produced by co-processing waste with kaolin clay in an FBSR process has been shown to be as durable as LAW glass. Monolithing of the granular FBSR product, which is one of the objectives of this current study, is being investigated to prevent dispersion during transport or burial/storage but is not necessary for performance. FBSR testing of a Hanford LAW simulant and a WTP-SW simulant at the pilot scale was performed by THOR Treatment Technologies, LLC at Hazen Research Inc. in April/May 2008. The Hanford LAW simulant was the Rassat 68 tank blend and the target concentrations for the LAW was increased by a factor of 10 for Sb, As, Ag, Cd, and Tl; 100 for Ba and Re (Tc surrogate); 1,000 for I; and 254,902 for Cs based on discussions with the DOE field office and the environmental regulators and an evaluation of the Hanford Tank Waste Envelopes A, B, and C. It was determined through the evaluation of the actual tank waste metals concentrations that some metal levels were not sufficient to achieve reliable detection in the off-gas sampling. Therefore, the identified metals concentrations were increased in the Rassat simulant processed by TTT at HRI to ensure detection and enable calculation of system removal efficiencies, product retention efficiencies, and mass balance closure without regard to potential results of those determinations or impacts on product durability response such as Toxicity Characteristic Leach Procedure (TCLP). A WTP-SW simulant based on melter off-gas analyses from Vitreous State Laboratory (VSL) was also tested at HRI in the 15-inch diameter Engineering Scale Test Demonstration (ESTD) dual reformer at HRI in 2008. The target concentrations for the Resource Conservation and Recovery Act (RCRA) metals were increased by 16X for Se, 29X for Tl, 42X for Ba, 48X for Sb, by 100X for Pb and Ni, 1000X for Ag, and 1297X for Cd to ensure detection by the analytic laboratory used for the demonstration and, as with the LAW simulant, without regard to potential impacts on product durability response such as TCLP. Details of the ESTD testing that was performed in April and May of 2008 are shown in Table 1 as the Operational Summary. The first eight tests were performed on LAW using a Denitration and Mineralization Reformer (DMR) temperature of 725 C and different ratios of clay:simulant of 675 g or 640 g of OptiKast clay per liter of simulant. The last four tests were performed on WTP-SW (originally referred to as LAW-Recycle) using a DMR temperature in the range of 680 C to 700 C with a mixture of 45/55 Sagger/OptiKast clay with 307 g clay/L simulant. The coal feed rates used in the FBSR processing are also shown as noted at the bottom of Table 1. It should be noted that the carbon feed rates are averaged over those periods.

The U.S. Department of Energy (DOE), Office of River Protection (ORP), is responsible for the remediation of the Hanford Site tank farms, including the 53 million gallons of highly radioactive mixed waste contained in 149 single-shell tanks (SST) and 28 double-shell tanks (DST). ORP manages the River Protection Project (RPP). Under the RPP, wastes retrieved from the tanks will be partitioned to separate the highly radioactive constituents from the very large volumes of chemical wastes that exist in the tanks. The volume of waste is the result of chemicals used in various Hanford Site processes, chemicals that were added to the tanks to reduce tank corrosion, and chemicals used in reprocessing and extraction of cesium and strontium. The highly radioactive constituents are to be vitrified, stored onsite, and ultimately disposed of as high-level waste (HLW) in the offsite national repository. The less radioactive chemical waste, referred to as low-activity waste (LAW), also would be vitrified and then disposed of onsite in trenches that comply with the Resource Conservation Act of 1976 (RCRA) and in compliance with DOE O 435.1, Radioactive Waste Management.

This report details the development of a reconfigurable in-tank robotic cleanup system called Houdini{trademark}. Driven by the general need to develop equipment for the removal of radioactive waste from hundreds of DOE waste storage tanks and the specific needs of DOE sites such as Oak Ridge National Laboratory and Fernald, Houdini{trademark} represents one of the possible tools that can be used to mobilize and retrieve this waste material for complete remediation. Houdini{trademark} is a hydraulically powered, track driven, mobile work vehicle with a collapsible frame designed to enter underground or above ground waste tanks through existing 24 inch riser openings. After the vehicle has entered the waste tank, it unfolds and lands on the waste surface or tank floor to become a remotely operated mini-bulldozer. Houdini{trademark} utilizes a vehicle mounted plow blade and 6-DOF manipulator to mobilize waste and carry other tooling such as sluicing pumps, excavation buckets, and hydraulic shears. The complete Houdini{trademark} system consists of the tracked vehicle and other support equipment (e.g., control console, deployment system, hydraulic power supply, and controller) necessary to deploy and remotely operate this system at any DOE site. Inside the storage tanks, the system is capable of performing heel removal, waste mobilization, waste size reduction, and other tank waste retrieval and decommissioning tasks. The first Houdini{trademark} system was delivered on September 24, 1996 to Oak Ridge National Laboratory (ORNL). The system acceptance test was successfully performed at a cold test facility at ORNL. After completion of the cold test program and the training of site personnel, ORNL will deploy the system for clean-up and remediation of the Gunite storage tanks.