Summary
Section 3125 of the National Defense Authorization Act (NDAA) for Fiscal Year 2021 (Public Law 116-283) calls for a Federally Funded Research and Development Center (FFRDC) to “conduct a follow-on analysis to the analysis required by section 3134 of the National Defense Authorization Act for Fiscal Year 2017 (Public Law 114-328; 130 Stat. 2769) with respect to approaches for treating the portion of low-activity waste at the Hanford Nuclear Reservation, Richland, Washington, intended for supplemental treatment.”1 The analysis “shall be designed, to the greatest extent possible, to provide decisionmakers with the ability to make a direct comparison between approaches for the supplemental treatment of low-activity waste at the Hanford Nuclear Reservation based on criteria that are relevant to decisionmaking and most clearly differentiate between approaches.” For the criteria that Congress wants considered, see Appendix A, which provides the complete texts of sections 3125 and 3134.
As with section 3134, section 3125 specifies that the National Academies of Sciences, Engineering, and Medicine (the National Academies) “conduct a review of the analysis” performed by the FFRDC that is independent of and concurrent with the FFRDC’s analysis and intended to improve the quality of the analysis. The U.S. Department of Energy (DOE) has contracted with Savannah River National Laboratory (SRNL), an FFRDC, to provide the required analysis. SRNL assembled a team of experts from SRNL, other national laboratories, and from outside the national laboratories’ network to perform the analysis. The Statement of Task (SoT) for the National Academies’ review is provided in Appendix B.
This second review report from the National Academies in response to the congressional mandate addresses the SoT given to the committee.
- Does the FFRDC’s report clearly lay out a framework of decisions to be made among the treatment technologies, waste forms, and disposal locations?
- Does the FFRDC’s report consider in its analysis all the elements, criteria, and factors specified in section 3125 of the National Defense Authorization Act of 2021?
- Does the FFRDC’s report provide additional analysis for the grout treatment approach as identified in the FFRDC report for section 3134 of the National Defense Authorization Act of 2017?
The committee’s comments in this second review report are based on an FFRDC report received April 12, 2022, titled “Follow-on Report of Analysis of Approaches to Supplemental Treatment of Low-Activity Waste at the Hanford Nuclear Reservation.” This 191-page report (Bates, 2022a, referenced in this review as Volume I) has 579 pages of supporting information (Bates, 2022b, referenced in this report as Volume II). Presentations supporting the material were provided by the FFRDC during a public meeting to discuss the reports in Richland, Washington, April 26-28, 2022.
As specified in section 3125, the National Academies’ committee is not charged to evaluate the supplemental treatment approaches or to recommend any particular approach, but is instead to review the FFRDC’s analysis. The FFRDC’s task is to provide data and analysis that will enable DOE, with congressional oversight, to decide on an approach, or some combination of approaches, to treat the supplemental low-activity waste (SLAW) by converting it into a waste form suitable for disposal.
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1 According to DOE’s Radioactive Waste Management Manual, low-activity radioactive waste means the waste that remains after as much of the radionuclides as technically and economically practicable have been removed from the tank waste, and that when immobilized in waste forms, may be disposed of as low-level waste in a near-surface facility if the waste meets criteria in the Waste Incidental to Reprocessing determination. Supplemental treatment refers to processing of the low-activity waste that is excess to that portion to be treated by vitrification in the Waste Treatment and Immobilization Plant.
As discussed in the first review report (NASEM, 2022), the impact of treating SLAW has ramifications across the entirety of the Hanford operations to meet the milestones of solidifying wastes for permanent disposal. As part of the directive, the FFRDC has selected four alternative approaches that are most likely to succeed because they have been demonstrated at other DOE sites including the Savannah River Site (SRS) and Idaho National Laboratory. The baseline alternative is vitrification with disposal at the Integrated Disposal Facility (IDF) at Hanford. The three others are treatment using fluidized bed steam reforming methods with on-site disposal (IDF), off-site grouting and disposal, and finally a phased approach that begins with off-site grouting and disposal and then transitioning to on-site operations. Section 3125 specified the requirement for “criteria that are relevant to decisionmaking and most clearly differentiate between approaches.” The criteria used by the FFRDC are:
- Long-term environmental and safety effectiveness
- Implementation schedule and risk
- Likelihood of successful mission completion
- Life-cycle costs
- Securing regulatory permissions
- Public acceptance
Notably, a recurring theme in the FFRDC report is the ongoing discussions with the Washington State Department of Ecology. DOE Hanford, its contractors, and regulators are working toward issuing the Resource Conservation and Recovery Act of 1976 (RCRA) Permit Modifications needed to allow disposal of vitrified LAW and associated grouted secondary solid waste at IDF.
Chapter 2 contains findings and recommendations from the committee’s review. Captured here is a summation of significant themes in the FFRDC analysis that the committee chooses to highlight. Based on the committee’s technical review of the FFRDC’s draft report and the presentation materials from the April 26-28, 2022, public meeting, the committee has reached consensus on the following findings and recommendations.
FINDINGS AND RECOMMENDATIONS
Finding 1: With respect to the FFRDC analytic framework, the committee finds:
Finding 2: The FFRDC report states (Volume I, p. 12) “Failures of selected DSTs may have little to no impact on the overall immobilization program if the tank failure does not prevent continued operations with the other DSTs.” The DOE tank integrity program, which applies to single-shell and double-shell tanks (DSTs), is briefly mentioned without references or a description; however, the addition of these references to the next version of the report would assist the stakeholders by providing a report with the necessary information for decision making. The committee understands and appreciates the challenges faced by DOE concerning Hanford tank integrity and the adoption of an active oversight, monitoring, and mitigation approach including historical measures such as dewatering tanks and installing asphalt water intrusion barriers in favor of focusing resources on getting on with cleanup sooner. While less than ideal, this approach is
allowing DOE to focus resources on accomplishing cleanup in a more timely fashion, but does involve risks if a tank’s physical integrity were to fail.
Recommendation A: The committee recommends that the FFRDC include in its report a discussion of the tank integrity program with annotated references to describe the strategy that is adopted and the status of the program to provide perspective for decision makers.
Finding 3: The FFRDC addressed the possibility of funding shortfalls by establishing a flat annual budget of $450 million and comparing this to the year-by-year funding requirements of SLAW treatment alternatives. Annual surpluses, if any, could be carried over for future use. Funding shortfalls are recognized to result in extensions of the cleanup mission duration and, thus, an additional cost penalty resulting from the assumed budget limit. Alternatives that had consistent shortfalls were deemed “unaffordable” and thus unlikely to be successfully implemented. The committee believes that this approach is inappropriate because the $450 million budget limit is arbitrary (strictly speaking) and based on predictions and value judgments that are better left to decision makers such as Congress.
Recommendation B: The “failure to complete due to funding shortfalls” subcriterion (Section 2.1.2) should be removed from key criterion #3, the FFRDC should remove the affordability concept from the likelihood of successful mission completion criterion and not assume any funding limit for this purpose. Instead, cost considerations should be addressed by estimating a life-cycle cost profile for constructing and operating each alternative that is designed to treat SLAW at the rate consistent with the nominal mission duration assumed in the report (operation from 2034 through 2075) while accounting for the variation in construction time. The FFRDC should then compare and contrast the life-cycle cost profiles accompanied by explicitly quantified sensitivity analyses about what funding levels would be required.
Finding 4: The committee notes that the report attempts to address how the confluence of costs, available budgets, and technological realities affect the cleanup mission timing. However, this attempt is confounded by the use of assumed annual budget limits (see Finding 3 and Recommendation B), cost tables that are not adequately explained, and limited comparison tables and graphics. The committee also notes that the insights about timing of cleanup appear to be limited to the final date of site closure, many decades out for all the alternatives. The committee expects that additional valuable insights could help differentiate the SLAW treatment alternatives by also displaying the rate of cleanup progress over time.
Recommendation C: The committee recommends that the FFRDC:
Finding 5: The FFRDC made a defensible decision to refrain from attempting to estimate in qualitative or quantitative terms the likelihood of specific regulatory outcomes; however, the regulatory approval criterion section would be strengthened by including a more in-depth discussion on potential challenges that may need to be addressed in obtaining the necessary various regulatory approvals.
Recommendation D: The FFRDC should include a discussion of issues associated with obtaining regulatory approval for the various options. Specifically, it would be helpful to focus on the significant adverse consequences of grouted SLAW not being acceptable for disposal at IDF or other out-of-state disposal sites.
Finding 6: Like the regulatory approval criterion, the FFRDC treated public acceptance as an uncertainty to be considered by the decision makers. The committee found that there was little discussion or analysis of the dimensions or potential ramifications of community and public acceptance in the FFRDC report. In particular, as the SLAW alternatives now consider off-site options, the importance of stakeholders along transportation routes and at disposal sites other than IDF have become relevant. In its work to date, the FFRDC has received input from individuals and organizations near Hanford, but not from stakeholders at other disposal locations under consideration or along transportation routes. The committee agrees with the findings in the report that the FFRDC should not attempt to estimate the likelihood, in qualitative or quantitative terms, of community and public acceptance outcomes.
Recommendation E: The FFRDC should expand its consideration of the consequences of potential impediments impacting the safe and expeditious SLAW management, such as grouted SLAW not being accepted for transportation, disposal at IDF, or other out-of-state disposal sites. The FFRDC should incorporate insights from public comments obtained to date in the final report, as well as the experiences of other sites that have transported radioactive waste to distant treatment or disposal locations.
Finding 7: Native American Nations and Tribes also have a unique interest in what remains on the site and the location and size of the areas that will be accessible to them following completion of treatment. The tribal representatives made a compelling case that maximizing tribal access (reducing contaminated or off-limits footprint), especially to areas of particular cultural or resource significance, are vital interests.
Recommendation F: The FFRDC should acknowledge as a subcriterion under key criterion #6 (community and public acceptance) consideration of the location and amount of land to which tribal members are likely to have access among the four alternatives that were evaluated and include this in the discussion of community and public acceptance (see Section 2.1.2.6).
Finding 8: The long lead time of the Vitrification 1 option results in a much later waste treatment start date than the other options. This inevitably contributes to an increased life-cycle cost and a higher potential for tank failure. The committee found the discussion on this observation to be lacking sufficient details in the FFRDC report.
Recommendation G: In their final report, the FFRDC should provide more discussion of the consequences for cost, time to completion, and likelihood of completion, given the delayed start date of the vitrification treatment.
Finding 9: If grouting is pursued, flexibility in disposal options will be important, given the uncertainties in future availability of disposal sites; therefore, the FFRDC’s case for pursuing flexibility via multiple pathways is well founded.
Finding 10: The methods and assumptions by which the FFRDC has calculated that pretreated liquid SLAW will qualify as low specific activity (LSA) waste are not described in adequate detail to allow the validity of the FFRDC claim that SLAW is LSA. In particular, the required calculations and associated information (e.g., feed vector concentration to sum-of-the fractions specific activity, radionuclide concentrations in the tanks and variability thereof, and how dose rates were calculated) are significant and are not in evidence in the report or by reference.
Finding 11: The FFRDC estimates the shipping rate of 5,000-gallon tanks to range from 23 to 45 tanks per month depending on the details of the assumed feed vector (Kalinina, 2022, slide 60). However, the FFRDC calculations for Limit 1 (specific activity) and Limit 2 (total activity) are based on the average of all shipments during each month. Based on the variability of Hanford tank waste compositions the committee would expect significant variability of the liquid SLAW composition in each tanker—and the specific and
total activity of the waste in the tanker. The implications of using monthly averages of pretreated liquid SLAW compositions when dose limits are on a tanker-by-tanker basis are not evident.
Recommendation H: The FFRDC report should address the implications of using monthly averages of pretreated liquid SLAW compositions when dose limits are on a tanker-by-tanker basis.
Finding 12: There appears to be an inconsistency between the dose rate limit at 3 meters having to be met by analyzing unshielded liquid waste and the statement that liquids will be transported in tanks that provide adequate shielding. Meeting the terms of the limit may require more pretreatment or smaller packages.
Recommendation I: The FFRDC needs to resolve this possible inconsistency. The FFRDC should
Finding 13: The report contains no discussion of the possibility of future unavailability of the Waste Control Specialists (WCS) or Clive, Utah, sites, even though such a possibility appears to be real and, if it were to happen, would have enormous negative potential consequences.
Recommendation J: The FFRDC report should elaborate the potential negative consequences of the unavailability of off-site disposal by (1) discussing the possibility that permission to dispose of grouted SLAW at WCS and/or Clive might never occur or someday be withdrawn; (2) discussing what is known about public acceptance regarding potential grouted SLAW disposal in Texas and Utah; and (3) providing more information surrounding the orphaned waste issue including specifics on how the issue might develop and what the consequences and coping measures might be.
Finding 14: The committee found that options Grout 4B and Grout 6, especially 6, are intended to emphasize flexibility (multiple pathways). Because of the numerous uncertainties that all alternatives involve, including the likelihood that time will bring new or refined treatment and disposal options, this is a sensible approach, and it should be as flexible as possible in considering variations in on-site and off-site alternatives.
Recommendation K: The differences between on-site and off-site grouting treatment should be separately analyzed in the same level of detail as on- and off-site disposal. The grout alternatives should identify potential variations on the on-site and off-site alternatives, such as tank side treatment or pretreatment, to provide DOE with the ability to make a financial “business case” with a range of budgetary possibilities for on- and off-site alternatives, including additional upfront DOE funding. This is also captured by a public comment from Rob Hastings (see Appendix C) regarding possible technologies to increase the speed with which tank waste is retrieved.
Finding 15: The FFRDC has made great progress in condensing the number of key criteria and the number of alternatives considered, as well as in presenting key information in side-by-side comparisons. There are, however, limits on how much a complex issue like this can be simplified, and some comparisons are oversimplified.
Recommendation L: Comparisons should be quantified, and as such, charts and graphs that lack a quantified basis should be eliminated (see Finding 4). This recommendation is particularly directed at the presentations in Section 4.0, Comparative Analyses (Bates, 2022a).
Finding 16: While stating a recommendation may assist decision makers in their deliberations regarding analyzed approaches, the process by which these recommendations were reached and who participated are not described. The off-site recommendation also avoids confronting the lack of a performance assessment for on-site grout disposal and the possibility that it might show that grout might be made acceptable by using additional pretreatment processing and/or getters (see Section 2.1.3.4).
Recommendation M: If the FFRDC is to offer a recommendation, it needs to be fully transparent concerning the methods used to reach the recommendation and the analysis that supports the recommendation. In particular:
Finding 17: The FFRDC provided additional analysis of grout for consideration including a number of alternatives described in detail and an examination of SRS’s experience with grouting.
