James H. Valentine
INEEL

Neil R. Davis
SRS

Karen Malone
West Valley Demonstration Project

P. Steve Schaus
Hanford

Eleven major Department of Energy (DOE) site contractors were chartered by the Assistant Secretary to use a systems engineering approach to develop and evaluate technically defensible cost savings opportunities across the complex. Known as the complex-wide Environmental Management Integration (EMI), this process evaluated all the major DOE waste streams including high level waste (HLW). Across the DOE complex, this waste stream has the highest life cycle cost and is scheduled to take until at least 2035 before all HLW is processed for disposal. Technical contract experts from the four DOE sites that manage high-level waste participated in the integration analysis: Hanford, Savannah River Site (SRS), Idaho National Engineering and Environmental Laboratory (INEEL), and West Valley Demonstration Project (WVDP). In addition, subject matter experts from the Yucca Mountain Project and the Tanks Focus Area participated in the analysis. Also, departmental representatives from the U.S. Department of Energy Headquarters (DOE-HQ) monitored the analysis and results.

Workouts were held throughout the year to develop recommendations to achieve a complex-wide integrated program. From this effort, the HLW Environmental Management (EM) Team identified a set of programmatic and technical opportunities that could result in potential cost savings and avoidance in excess of $18 billion and an accelerated completion of the HLW mission by seven years. The cost savings, schedule improvements, and volume reduction are attributed to a multifaceted HLW treatment disposal strategy which involves waste pretreatment, standardized waste matrices, risk-based retrieval, early development and deployment of a shipping system for glass canisters, and reasonable, low cost tank closure.

In 1944, the United States began reprocessing spent nuclear fuel from the many government nuclear reactors. These reactors were operated for a wide variety of reasons including research, tests, power, weapons production, and naval propulsion. The purpose in reprocessing was to extract reusable nuclear material from the spent fuel. In the Atomic Energy Act of 1953, the first cycle raffinate byproduct from reprocessing of spent nuclear fuel (SNF) was defined as high level waste (HLW), and HLW was produced at three of the government owned sites throughout the United States. These included the Savannah River Site (SRS) located in South Carolina, the Hanford Site located in Washington, and the Idaho National Engineering and Environmental Laboratory (INEEL). A fourth commercially licensed facility, the Western New York Nuclear Services Center (now the West Valley Demonstration Project) (WVDP) also reprocessed SNF and generated HLW.

The SRS began reprocessing operations in 1954. Between 1954 and 1992, 129,000 m³ of HLW has accumulated in 51 carbon steel tanks. SRS is the only site that will continue to generate HLW as it reprocesses the remaining "at risk" SNF. To prepare its HLW for disposal, the SRS Site Treatment Plan requires SRS to produce an average of 200 glass canisters through the Defense Waste Processing Facility (DWPF) per year until all the HLW is vitrified. Under the current schedule this will be completed in 2028. As of January 1998, 250 canisters have been produced or 4.2% of the total.

The Hanford site began reprocessing in 1944. Currently, 221,000 m³ of waste is stored in 177 carbon steel tanks. The Hanford Federal Facilities Agreement and Consent Order (also known as the Tri-Party Agreement) requires removal of waste from the single shell tanks by 2018; closure of single shell tanks by 2024; and completion of low activity waste and high activity waste immobilization by 2024 and 2028, respectively. Currently Hanford is in preconceptual design of the privatized immobilization facilities. Contract award is expected in May of 1998.

The INEEL began reprocessing in 1953. Between 1953 and 1992, 34,000 m³ of HLW was generated and stored in 10 stainless steel 1,100 m³ tanks. In contrast to other sites, INEEL stored its HLW as an acidic, liquid waste. Since 1963, the liquid waste has been converted to a granular solid through a calcination process, and the granular solid is stored in stainless steel tanks grouped together in vaults of four to seven tanks. As of January 1998, 4,000 m³ of solids are stored in 34 tanks and 5,300 m³ of liquid are stored in nine stainless steel tanks. By direction of a court order Settlement Agreement with the State of Idaho, the liquid will be removed from the tanks by 2012 and the solids processed and ready for transportation out of Idaho by 2035.

West Valley began commercially reprocessing in 1966. Between 1966 and 1972, West Valley generated and stored 2,270 m³ of HLW in two carbon steel tanks through the reprocessing of approximately 640 metric tons of spent nuclear fuel. The Department of Energy (DOE) took over operation of the facility in 1982. The WVDP Act of 1980 assigned DOE the responsibility of vitrifying the HLW left from the commercial reprocessing operations, decontaminating and decommissioning the facilities used to process and store the HLW, and disposing of the waste generated as part of the vitrification. Until these responsibilities are fulfilled, DOE cannot return responsibility for the site to the state of New York. However, the WVDP Act contains no dates for any activity completion. From 1988 through 1995, the HLW was pretreated to remove the low activity fraction, which was blended with cement in 71-gallon drums now stored on site. Vitrification of the remaining high activity waste fraction began in June 1996. The schedule shows completion in June 1998, with planning underway for a smaller follow-on campaign to process high activity tank residuals. As of January 1998, 180 canisters (82% completion) have been produced.

Until December of 1996, each of these four sites was dealing with their HLW somewhat independently. Even though each was aware of the other's processes, very little was done to integrate. The need to integrate was mainly driven by the $56.5 billion life cycle cost associated with all the HLW programs; this is the highest cost of any waste stream managed under the DOE. DOE's Environmental Management (EM) division is responsible for HLW disposition. In 1996, EM initiated an integrated approach with teams looking at various waste streams. In the EMI effort associated with HLW, technical contract experts from the four DOE sites that manage HLW participated in the integration analysis: Hanford, SRS, INEEL, and WVDP. In addition, subject matter experts from the Yucca Mountain Project and the Tanks Focus Area participated in the analysis. Also, departmental representatives from DOE-HQ monitored the analysis and results.

After evaluating each of the site-specific HLW systems, the HLW EMI team developed a number of opportunities for integrating liquid waste treatment and disposal, and tank closure for HLW stored at SRS, WVDP, Hanford, and INEEL, as well as the INEEL calcined solid HLW and the Hanford cesium (Cs) and strontium (Sr) capsules. (Although some of these wastes do not meet the source-based definition of HLW as first cycle raffinate, they are managed in the DOE system as HLW). The potential cost savings and avoidances associated with implementing these opportunities are in excess of $18 billion. In addition, the HLW mission across the country would be completed seven years earlier, and a volume reduction of nearly 10,000 m³ of glass to the repository would be realized. Although the potential for cost savings is high, the barriers, such as shipping and stakeholder acceptance, are significant.

The EMI team used a systems engineering approach to develop the alternatives and eventually select a proposed path. Disposition maps were used initially to develop the baseline for each site, and these maps became a key to pulling together the entire HLW complex-wide picture. The disposition maps showing the baseline and selected alternative for each site is in Figures 1 through 4. Through the integration process, three viable alternatives were developed:

Maintain and process all HLW at the respective site location until time to ship to a federal repository. Cost savings are realized primarily for Hanford and Idaho, by using a standard HLW matrix and disposal form. This reduces the cost of an additional waste form. This alternative has the highest probability of success of the three alternatives developed, however, it also reflects the lowest cumulative cost savings.

Leverage of existing and/or common facilities on a regional basis for HLW processing and interim storage. Hanford and SRS would serve as the processing and interim storage facilities for HLW. On the western side of the country, the INEEL will dissolve the calcine waste and separate the Cs and Sr. If all the HLW in the complex were vitrified without separation before transportation to a final disposal in a federal repository, the amount of waste would be far beyond the storage volumes available. By separating out the material that can be disposed of in a Class A landfill, the volume and subsequently cost is greatly reduced. This material is the low activity waste (LAW), and the remaining material, high activity waste (HAW), will be vitrified. Separations can be done by several types of processes depending on the original waste type. In the extraction process proposed for the INEEL, the Cs and Sr will be extracted because they are high gamma emitters that will decay to insignificant levels in 200 to 300 years. By extracting these isotopes, the remaining process has a low radiation field, and this greatly reduces costs for facilities and handling equipment. The HAW fraction, without the high gamma emitters of Cs and Sr, would be shipped to Hanford for vitrification. This process simplifies the shipment to Hanford for vitrification and eliminates the construction of a vitrification facility at INEEL. On the Eastern side of the country, WVDP would ship vitrified waste to SRS for interim storage, eliminating the cost of a storage facility and the associated surveillance and maintenance costs. This will also accelerate the development of a HLW shipping system and approved shipping process for use by all sites. This alternative has a moderate probability of success with moderate projected cost savings.

Minimize the number of new facilities required in the DOE complex by implementing extensive transportation of previtrified HLW. This alternative proposes using WVDP to demonstrate vitrification of Hanford tank waste, and uses the SRS Defense Waste Processing Facility to vitrify the remaining pretreated Hanford and INEEL HLW. Dissolution and separation of radionuclides would reduce the volume of Hanford and INEEL HLW requiring immobilization and disposal. A privatized pretreatment facility would be built and operated at Hanford to process Hanford tank waste and INEEL calcine waste (INEEL calcine would be shipped to Hanford for pretreatment). This alternative assumes that existing transportation routes for nuclear fuel would be used and that the host states (New York and South Carolina) would be receptive to the extended operation of those sites to handle waste from other sites. This alternative has a low probability of success, but a high projected cost savings.

Regional processing. The alternative that was selected for further evaluation is known as the preferred alternative and was developed from the elements of the three original alternatives. As with the second alternative, this is based on a regional approach. The significant changes and savings would be at the two western facilities, Hanford and INEEL. The strategy has the following features:

• Use existing INEEL Cs and Sr Storage Capacity facilities - INEEL currently has empty tanks located in vaults, and this facility would be used for long term storage of Cs and Sr from both Hanford and INEEL. The two isotopes decay to insignificant levels in 300 years. In addition, the Cs and Sr capsules currently stored in the Hanford Waste Encapsulation and Storage Facility would be transported to the INEEL and stored in this facility.
• Accelerate Calcine Separations of INEEL HLW - Accelerate the current plan for retrieving the HLW calcine and separating it into a high activity fraction and a low activity fraction and transport the HAW fraction to Hanford.
• Use Hanford Vitrification Capabilities for INEEL HLW - Vitrify the high activity waste fraction from INEEL in the planned facilities at Hanford and store it until shipped to a federal repository along with the vitrified Hanford waste.
• Reduce Hanford HLW Volume - Hanford waste would be processed through an aggressive pretreatment similar to the process proposed at the INEEL. This enables better separation of the LAW fraction, reduction of waste volumes, and better dissolution of solids in the high-activity sludge. This significant volume reduction of the vitrified waste would reduce federal repository disposal costs.
• Implement Risk-Based HLW Retrieval and Tank Closure - Focus on removing waste from tanks that pose the highest health and safety risks. This activity would mainly be applied at Hanford and INEEL, although the other two sites would benefit to a lesser degree to the integrated closure activities.

• WVDP HLW Canisters to SRS - Develop and deploy a process for shipping vitrified HLW canisters to SRS for interim storage. This could complete the WVDP mission eleven years early as the vitrified canisters would be stored at SRS and transported with the SRS vitrified waste to a federal repository. The shipping casks and procedures developed to support this activity would be used at Hanford to transport the Hanford and INEEL vitrified product to a repository.

Although the strategies for the HLW Complex Integration have the potential for life cycle cost savings and avoidance of $18 billion, several major issues require resolution:

• Transportation of HLW Between Sites - Spent reactor fuel is routinely transported via shipping routes throughout the US. Even though the HLW would be in a solid form, this type of waste shipment has not been done on a routine basis. The technology and regulations are such that the waste can be shipped, but fear and public perception currently restrict any shipments.
• Stakeholder Interests and State Equities - The general consensus of the stakeholders is that they do not want the wastes left in their state nor do they want to be a "dumping ground" for other states wastes. Even though the waste would be brought in only for processing before being transported to a repository, the concern is that the waste would never leave. For example, the State of Idaho has to accept Hanford's Cs and Sr and store INEEL's Cs and Sr. In return, the INEEL HLW will be removed from Idaho seven years ahead of the Settlement Agreement date and up to 40 years earlier than the vitrified HLW is scheduled for transportation to a repository. INEEL waste is required to be "road ready" by 2035. The State of Washington would have to accept the INEEL HLW for vitrification and storage until shipped to a repository.

The Office of Environmental Management continues to be driven to do more with less. Integration across the DOE complex for HLW provides an opportunity to achieve full waste and material disposition within tight fiscal constraints. The HLW across the DOE complex carries with it the highest life cycle cost of over $56 billion and the most distant schedule completion date of 2035. This recommended integration of the HLW brings an opportunity to reduce the life cycle cost by $18 billion and improve the schedule by at least seven years. Significant break- throughs will be required to complete the HLW mission across the complex. The technical solutions are very achievable but, require cooperation between sites and stakeholders. To move forward, process flow sheets have to be further refined along with costs and schedules, and equity issues have to be resolved.

These initiatives provide an opportunity to solve a complex problem that is costly and time consuming. This contractor integration effort has been a crucial step to solve the HLW problem on a complex-wide basis, and feedback from decision makers and stakeholders will determine the extent to which these integration opportunities will be implemented in the area of DOE's HLW program.

1. A Contractor Report to the Department of Energy on Environmental Management Baseline Programs and Integration Opportunities (Discussion Draft), INEL-EXT-97-00493, May 1997.

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