Tank Waste Remediation System Research Articles

Allocating Vendor Risks in the Hanford Waste Cleanup

Organizations may view outsourcing as a way to manage risk. We developed a decision-analytic approach to determine which risks the buyer can share or shift to vendors and which ones it should bear. We found that allocating risks incorrectly could increase costs dramatically. Between 1995 and 1998, we used this approach to develop the request for proposals (RFP) for the US Department of Energy's (DOE's) privatization initiative for the Hanford tank waste remediation system (TWRS). In the model, we used an assessment protocol to predict how vendors would react to proposed risk allocations in terms of their actions and their pricing. We considered the impact of allocating each major risk to potential vendors, to the DOE, or to both and identified the risk allocation that would minimize the DOE's total cost—its direct payments to vendors plus the costs of any residual risks it accepted. Allocating inappropriate risks to the vendor would have increased costs because the vendor would add a large risk premium to its bids, while allocating inappropriate risks to the DOE also would have increased costs because the vendor would not take adequate risk-reduction measures. With the improved risk allocation, the RFPs resulted in bids that were acceptable to the DOE.

An updated cost study for enhanced sludge washing of radioactive waste

AbstractThis article updates previous cost savings studies conducted to evaluate the use of enhanced sludge washing (ESW) of high‐level radioactive waste at the United States Department of Energy Hanford Site. The cost savings estimate was updated using stochastic analysis based on new information from the Independent Review of Hanford High Level Waste Volume and the more recent Tank Waste Remediation System Operation and Utilization Plan. It is estimated that implementation of ESW in the tank waste remediation system (TWRS) at the Hanford Site can save approximately $4.8 billion compared to the use of an alternative, simpler water wash. The simpler water wash dissolution was found to be 85 percent as effective as the ESW dissolution. Further, the updated remediation cost estimate of $4.8 billion savings is uncertain only within ±$1.6 billion at the 95 percent confidence interval. © 2003 Wiley Periodicals, Inc. Reprinted from Remediation Volume 12, Number 2.

An Updated Cost Study for Enhanced Sludge Washing of Radioactive Waste

AbstractThis article updates previous cost savings studies conducted to evaluate the use of enhanced sludge washing (ESW) of high‐level radioactive waste at the United States Department of Energy Hanford Site. The cost savings estimate was updated using stochastic analysis based on new information from the Independent Review of Hanford High Level Waste Volume and the more recent Tank Waste Remediation System Operation and Utilization Plan. It is estimated that implementation of ESW in the tank waste remediation system (TWRS) at the Hanford Site can save approximately $4.8 billion compared to the use of an alternative, simpler water wash. The simpler water wash dissolution was found to be 85 percent as effective as the ESW dissolution. Further, the updated remediation cost estimate of $4.8 billion savings is uncertain only within ±$1.6 billion at the 95 percent confidence interval. © 2002 Wiley Periodicals, Inc.

Privatization

Following a thorough analysis of the components of the Tank Waste Remediation System (TWRS), the U.S. Department of Energy (DOE) decided that application of privatization techniques could save the Department money, improve the efficiency of its operations, balance, departmental budgets, and control cost growth. The TWRS glassification (vitrification) plants were proposed as potential privatization candidates. This article focuses on how different decision tools affected the development of the TWRS privatization project and how these tools provided decision-makers with the information required to negotiate and renegotiate the Contract and to decide whether the privatization project should continue or move to an alternative path (a nonprivatization contracting approach). In this case, the tools helped DOE with its decision to terminate the contract. While developed and perfected on TWRS privatization, these tools are applicable to other privatized business ventures requiring project finance.

Dynamic Simulation of Hanford Tank Waste Remediation System

Cleaning up and disposing of approximately 50 years of nuclear waste is the main mission at the U.S. Department of Energy's Hanford Nuclear Reserva tion, located in the southeastern part of the State of Washington. A major element of the total cleanup effort involves retrieving, processing, and disposing of radioactive and hazardous waste stored in 177 underground storage tanks. This effort, referred to as the Tank Waste Remediation System (TWRS), is expected to cost billions of dollars and take approxi mately 25 years to complete. Several computer simulations of this project are being created, focusing on both programmatic and detailed engineering issues. This paper describes one such simulation activity, using the ithink™ computer simulation software. The ithink™ simulation includes a representation of the complete TWRS cleanup system, from retrieval of waste through intermediate processing and final vitrification of waste for disposal. Major issues addressed to date by the simulation effort include the need for new underground storage tanks to support TWRS activities, and the estimated design capacities for various processing facilities that are required to support legally mandated program commitment dates. This paper discusses how the simulation was used to investigate these questions.

PRIVATIZING GOVERNMENT OPERATIONS A SYSTEMS APPROACH

AbstractThe Hanford Area is a U.S. Department of Energy (DOE) reservation in Southeastern Washington, where the primary mission for nearly fifty years was production of nuclear weapons materials. It is now the nation's largest superfund site and its sole mission is environmental remediation of the mixed wastes generated during plutonium production. A large fraction of these wastes are stored in 177 underground tanks and are the subject of the DOE's Tank Waste Remediation System (TWRS) Program. Since its inception the TWRS Program has been managed by a Maintenance and Operations (M&O) contractor.The DOE is now considering the privatization of a portion of this program and has recently issued a Request for Proposals (RFP) seeking new, qualified, private vendors. Successful bidders will be expected to build waste processing facilities with their own financial resources and to recover their costs by charging fixed prices for the various products delivered to the DOE. Because the TWRS Program is such a large, complex, and expensive undertaking, the privatization initiative will be conducted in two phases: a small proof‐of‐concept phase, followed by full‐scale production. A primary objective of the proof‐of‐concept phase is to test this new contracting approach by determining the interest of private companies and demonstrating their technical capabilities.The key to a successful demonstration is establishing the right set of requirements to be satisfied by the private vendors. These requirements must be consistent with the existing requirements set developed over the past three years by the M&O contractor. This paper presents the results of a systems engineering effort that was conducted in support of the RFP preparation and had to be coordinated with an ongoing program. Much of the effort was focused on the specification of new proof‐of‐concept requirements that are directly traceable to corresponding requirements in the M&O's RDD‐100® database. A new functions and requirements database was created for this first privatization phase using CORE®, a systems engineering support tool, produced by Vitech Corporation.

Distribution of 14 elements from two solutions simulating Hanford HLW Tank 102-SY (acid-dissolved sludge and acidified supernate) on four cation exchange resins and five anion exchange resins having different functional groups

As part of the Tank Waste Remediation System program at Los Alamos, we evaluated a series of cation exchange and anion exchange resins for their ability to remove hazardous components from radioactive high-level waste (HLW). The anion exchangers were ReillexTM HPQ, a polyvinylpyridine resin, and four strong-base polystyrene resins having trimethyl, triethyl, tripropyl, and tributyl amine as their respective functional groups. The cation exchange resins included AmberlystTM 15 and AmberlystTM XN-1010 with sulfonic acid functionality, DuoliteTM C-467 with phosphonic acid functionality, and polyfunctional DiphonixTM with diphosphonic acid, sulfonic acid, and carboxylic acid functionalities. We measured the distributions of 14 elements on these resins from solutions simulating acid-dissolved sludge (pH 0.6) and acidified supernate (pH 3.5) from underground storage tank 102-SY at the Hanford Reservation near Richland, Washington, USA. To these simulants, we added the appropriate radionuclides and used gamma spectrometry to measure fission products (Ce, Cs, Sr, Tc, and Y), actinides (U, Pu, and Am), and matrix elements (Cr, Co, Fe, Mn, Zn, and Zr). For each of the 252 element/resin/solution combinations, distribution coefficients (Kds) were measured for dynamic contact periods of 30 minutes, 2 hours, and 6 hours to obtain information about sorption kinetics from these complex media. Because we measured the sorption of many different elements, the tabulated results indicate which unwanted elements are most likely to interfere with the sorption of elements of special interest. On the basis of these 756 measured Kd values, we conclude that some of the tested resins appear suitable for partitioning hazardous components from Hanford HLW.