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Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors (2016)

Chapter: 6 Conversion Program: Status and Management

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Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
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6

Conversion Program: Status and Management

This chapter contains the committee’s review of the current status and progress toward conversion of existing research reactors using highly enriched uranium (HEU) fuel and the U.S. Department of Energy’s (DOE’s) progress and approach to managing the conversion program. These reviews were called for in Tasks 2 and 3 of the study charge.

REVIEW OF CIVILIAN RESEARCH REACTOR STATUS

As noted in Chapter 1, the committee’s interpretation of Task 2 was to review progress since the last National Academies of Sciences, Engineering, and Medicine (the Academies) report on medical isotope target and research reactor fuel conversion to low enriched uranium (LEU) (NRC, 2009). Also noted in Chapter 1 was the decision by the committee to include HEU fuel stored at reactor sites (fresh and spent fuel) as part of its charge.

The Convert Program

DOE’s Global Threat Reduction Initiative (GTRI) was organized into three pillars: convert, remove, and secure. In 2009, the main activities of the Convert Program were the conversion of mainly nondomestic research reactors and the development of new high-density LEU fuels to enable the conversion of most of the remaining U.S. reactors (see Chapter 4). The scope of and time lines for the Convert Program were as follows (NRC, 2009):

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
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  • To convert the remaining 125 research reactors using HEU fuel by 2018.
  • To qualify high-density uranium-molybdenum (UMo) dispersion fuel by 2010 and the UMo monolithic fuel by 2011.

DOE’s Office of Material Management and Minimization (M3), established in January 2015, is organized similarly into three main pillars: convert, remove, and dispose (“dispose” replacing “secure” in the program structure).1 The current activities of the Office of Conversion (previously the Convert Program under GTRI) remain the conversion of nondomestic research reactors and development of very high-density LEU fuel to convert U.S.-based high performance research reactors (USHPRRs). The updated scope and time lines of the Convert Program are as follows:

  • To convert or verify the shutdown of the remaining 112 research reactors using HEU fuel by 2035.2
  • To qualify very high-density UMo monolithic fuel by 2022.

The expanded scope and time lines are discussed in Chapters 2 and 4, and the program decision to focus on UMo monolithic fuel (the “one-for-all” approach) is discussed in Chapter 4. In summary, the scope of the program increased partially in response to the 2009 Academies report recommendation that DOE National Nuclear Security Administration (NNSA) consider defense-oriented research reactors to be within scope (NRC, 2009, p. 162). From 2009 to 2014, the number of reactors on GTRI’s conversion list increased from 129 to 200. The time line for completion of the conversion or shutdown of all these reactors increased from 2018 to 2035 (see Figure 2.2). Part of this schedule expansion could be attributed to the larger number of reactors on the list, but unanticipated irradiation test failures of the UMo monolithic fuel and challenges in fuel fabrication and manufacturing also contributed.

Evaluating progress in the U.S. conversion program since 2009 requires consideration of GTRI’s accomplishments since the start of the conversion program in 1978. Figure 6.1 shows the number of research reactor conversions and shutdowns since 1978 (the start of the Reduced Enrichment for Research and Test Reactors [RERTR] Program), with projections extending to 2035 (Waud, 2015). The figure shows an increased rate of conversion

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1 The reorganization of the DOE’s National Nuclear Security Administration’s Office of Defense Nuclear Nonproliferation resulted in the broader material management and minimization activities such as the disposal of mixed oxide (MOX) fuel being grouped with convert and remove.

2 The Fiscal Year (FY) 2015 budget justification reports that 88 of the 200 identified HEU-fueled research reactors had been converted or shut down (DOE, 2014, p. 462).

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
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FIGURE 6.1 Number of reactors verified as converted or shut down as a function of time (blue line). The eras of the RERTR Program (1978–2004) and the GTRI Convert Program (2004–-2015) are shown by the vertical lines. The M3 Office of Conversion was created in 2015. Future conversions and shutdowns are extrapolated to 2035, the projected end date for the conversion program. The horizontal dotted line at 162 research reactors corresponds to the sum of the converted and shutdown reactors (90) and the total number of civilian research reactors currently using HEU fuel as established at the joint International Atomic Energy Agency–Academies meeting (72, see Appendix E). The horizontal line at 200 research reactors is the last reported total research reactors within scope in the NNSA FY 2015 budget request. The vertical dotted line at 2009 indicates the beginning of the period reviewed in the present report. SOURCE: Modified from Waud (2015), Courtesy of the National Nuclear Security Administration (DOE).

beginning in 2004 with the start of GTRI. Part of this increase is a reporting artifact: the RERTR Program did not report shutdown reactors in its totals, but GTRI’s Convert Program did. The pace of conversions and shutdowns has remained roughly constant over the past 5 years and is projected to continue at about the same pace through 2035. Although the goal of the program to minimize the use of HEU in civilian research reactors is served both by conversions to LEU fuel and by reactor shutdowns, very few of these shutdowns resulted from an HEU minimization program. Rather, they occurred for other reasons such as reactor obsolescence (e.g., through the development of powerful computational codes), lack of current mission, or cost savings.

GTRI converted (or confirmed shutdown of) a total of 24 research reactors in its first 5 years (2004–2008) (Figure 6.1; further details in Figure 6.2). In 2009, the individual rates of converted and shutdown research reactors changed. Prior to 2009, the program converted 3.6 research reac-

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
×

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FIGURE 6.2 Reactors converted or verified as shut down by the GTRI Convert Program between 2004 and 2014. The blue diamonds are the cumulative conversions and shutdowns; the red squares indicate conversions only; and the green triangles indicate shutdowns only. The change in slope of the conversion and shutdown lines in 2008 indicates a slowing of conversions and an increased rate of shutdowns. The rate of cumulative shutdowns and conversions is nearly constant. See text and Table 6.1 for more details. SOURCE: Data from Landers, written communication, April 2015.

tors per year and confirmed the shutdown of 1.2 per year on average. After 2009, the program converted fewer research reactors per year (1.5), but confirmed more shutdowns (3.2 per year), as reflected in the changing slopes of the lower lines in Figure 6.2.

Table 6.1 summarizes conversion and shutdown information from 2004 through 2014. The table shows that, since 2009, the number of conversions worldwide has decreased over the previous 5 years, from 18 to 9 conversions. The number of shutdowns has increased from 6 to 19 over the same time period. Notably, nearly one-half of all shutdowns since 2009 have occurred in Russia. Table 6.2 lists all of the reactors that have been shut down or converted since 2009.

By 2009, many of the reactors that could convert with existing fuels had done so. The change in slopes in Figure 6.2 therefore corresponds to a shift in focus to reactors that need new LEU fuel to be qualified to convert (see Chapter 4) and to reactors whose conversions are dominated by nontechnical factors (see Chapter 5). Since 2009, significant work has taken place on developing and testing very high-density LEU fuels (see Chapter 4) and returning a significant amount of U.S.- and Russian-origin HEU fuel to

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
×

TABLE 6.1 GTRI Conversion and Shutdown Statistics (2004–2014)

YEAR 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2004-2008 2009-2014
TOTAL worldwide                          
Converted 1 2 4 5 6 3 1 1 2 1 1 18 9
Shut down 0 1 1 2 2 1 5 2 4 2 3 6 17
Russia                          
Converted 0 0 0 0 0 0 0 0 0 0 1 0 1
Shut down 0 0 0 0 0 0 3 1 1 0 2 0 7
Elsewhere                          
Converted 1 2 4 5 6 3 1 1 2 1 0 18 8
Shut down 0 1 1 2 2 1 2 1 3 2 1 6 10
TOTAL worldwide                          
Percentage converted 100 67 80 71 75 75 17 33 50 33 25 75 35
Percentage shutdown 0 33 20 29 25 25 83 67 50 67 75 25 65

SOURCE: Modified from data from Landers, written communication, April 2015.

TABLE 6.2 Reactors Converted or Shut Down since 2009

Country Facility Site Converted or Shut Down Comments and Conversion Status
Bulgaria IRT-2000 Institute for Nuclear Research and Nuclear Energy 2009 Shut down
United States RTR—University of Wisconsin - Research Reactor University of Wisconsin 2009 Full
Hungary BRR Atomic Energy Research Institute 2009 Full
United States NRAD—Neutron Radiography Reactor Idaho National Laboratory 2009 Full
Russia PhS-4 (FS-4) ENTEK 2010 Shut down
Russia PhS-5 (FS-5) ENTEK 2010 Shut down
Russia STRELA IPPE 2010 Shut down
Japan KUR Kyoto University 2010 Full
Chile RECH-2 Research Reactor Lo Aguirre Nuclear Centre 2010 Shut down
China MNSR-SD Shandong Geology Bureau 2010 Shut down
Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
×
Country Facility Site Converted or Shut Down Comments and Conversion Status
Czech Republic REZ 10-MW Research Reactor Nuclear Research Institute, Rez 2011 Full
Russia BR-10 IPPE 2011 Shut down
Canada SLOWPOKE Halifax Dalhousie University 2011 Shut down
Japan YAYOI University of Tokyo 2012 Shut down
Japan MITI Standard Pile National Metrology Institute of Japan 2012 Shut down
Netherlands LFR Nuclear Research & Consultancy Group 2012 Shut down
Poland MARIA Research Reactor Institute of Atomic Energy in Otwock-Swierk 2012 Full
Kazakhstan VVR-K CA Institute of Nuclear Physics 2012 Full
Russia RF-GS IPPE 2012 Shut down
India Apsara Bhabha Atomic Energy Centre 2013 Shut down
China MJTR Nuclear Power Institute of China 2013 Full
United Kingdom Consort Imperial College 2013 Shut down
Russia ARGUS Kurchatov Institute 2014 Full
Russia ROSSIYA Icebreaker 1 2014 Shut down
Russia ROSSIYA Icebreaker 2 2014 Shut down
Uzbekistan Foton Foton 2014 Shut down

SOURCE: Modified from data from Landers, written communication, April 2015.

its country of origin.3 Before the recent deterioration in the U.S.-Russian relationship described in Chapter 5, U.S. and Russian scientists collaborated to study the feasibility of converting Russian research reactors to

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3 See President Obama’s Four-Year Initiative (http://nnsa.energy.gov/sites/default/files/nnsa/12-13-inlinefiles/2013-12-12%204%20Year%20Effort.pdf, p. 5). The Fuel Return Program returned 37.3 kg of HEU from Kazakhstan to Russia in December 2014, despite worsening relations between the United States and Russia (communication with Sarah Dickerson, NNSA, January 2015).

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
×

LEU, completed the conversion of one Russian domestic research reactor, and established that most other Russian domestic research reactors could be converted.4 The United States and Russia also continued to work together to return HEU fuel to its country of origin.

The Remove Program

The fuel Take Back Program, the “remove” pillar of GTRI, was originally established to provide a path for the removal of U.S.-origin HEU fuel and spent LEU fuel as an incentive to countries to convert. Like the Convert Program, the Remove Program has expanded its scope over the years; it now includes some weapon-usable material supplied by countries other than the United States as well as additional forms of nuclear material.5 The Remove Program is organized into three components (Dickerson, 2014):

  • U.S.-origin fuel return program: The return of U.S.-origin HEU and LEU to the United States for disposition was instituted to encourage countries to convert research reactors from HEU to LEU fuel. By the end of 2014, 1,264 kg of HEU had been removed, with an additional 447 kg slated for removal by 2019. Nearly all of the material under this program has been returned or is planned to be returned by 2019, with the exception of fuel from Canada. The U.S.-origin fuel return program focuses on fuel returning from Training, Research, Isotopes, General Atomics (TRIGA) reactors and materials test reactors (MTR). All of these research reactors have converted and returned U.S.-origin fuel to the United States (or plan to convert by the program’s end date).
  • Russian-origin fuel return program: This portion of the program is dedicated to the return of Russian-origin HEU to Russia for disposition. So far, 2,121 kg of HEU have been removed, with an additional 404 kg targeted for removal by 2020.
  • Gap material program: This effort addresses weapon-usable materials not covered under the U.S.- or Russian-origin programs. So far, 1,825 kg of HEU and plutonium have been removed, with a goal of removing an additional 1,431 kg by 2022.

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4 The licensing and conversion of four additional Russian reactors had been planned in conjunction with Argonne National Laboratory and Russian laboratories, but the decision to convert has not yet been made and the programs have been put on hold (Roglans, 2015).

5 However, the Remove Program does not target all U.S.-origin HEU and weapon-usable material. HEU material not associated with research reactor conversion is beyond the scope of the GTRI Convert Program.

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
×

Since it began in 1996, the fuel return programs have removed some 5,000 kg of material, including more than 1,500 kg removed in Fiscal Year (FY) 2013 (DOE, 2014; NNSA, 2014), but a significant amount of material—several metric tons—is outside the scope of the return program. The U.S.-origin program is scheduled to end in May 2019 and the Russian-origin program will end in 2022 (a few specific exceptions extend the time line as far into the future as 2029 [Dickerson, 2014]). Legal6 and logistical issues pertaining to transport of returned material and its final resting place also limit the rate at which material can be returned to the United States.

The M3 Office of Conversion currently reports progress toward its goal of eliminating HEU from civilian research reactors by counting the number of reactors using HEU that have either converted or shut down. These numbers can be seen in annual reports to Congress (e.g., DOE, 2014) or during presentations at international meetings such as the annual RERTR or European Research Reactor Fuel Management (RRFM) meetings. However, this metric does not fully convey progress toward minimizing and eliminating use of HEU fuel for research reactors for two reasons. First, M3 defines a “converted” reactor as one in which at least one LEU fuel assembly has been inserted. In the case of some reactors, HEU fuel remains in the reactor until the conversion is complete.7 In addition, this metric does not measure how much HEU fuel is in place at research reactors, whether it is in-core or in storage (fresh or spent fuel).

The conversion of the University of Michigan (UM) Ford Nuclear Reactor (FNR) in 1981 suggests the need for additional conversion metrics. The FNR conversion was the demonstration project for the RERTR Program. Using the current M3 conversion metric, the number of existing HEU-fueled civilian research reactors decreased by one in 1981.8 However, spent HEU fuel remained at UM until October 1987, when it was shipped to the Savannah River Nuclear Solutions. Consequently, the threat posed by this HEU fuel remained largely unchanged for almost 6 years.

A full assessment of the progress of the reactor conversion program is a function of the number of HEU-fueled reactors, the number of research

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6 Federal facility agreements (FFAs, also known as “tri-party agreements”) between the U.S. Environmental Protection Agency (EPA), DOE, and states involved in federal cleanup of U.S. government nuclear sites govern the types and amount of spent nuclear fuel allowed within the state. The FFA between EPA, DOE, and South Carolina can be found at http://www.srs.gov/general/programs/soil/ffa/ffa.pdf.

7 For some reactor cores, fuel replenishment takes place one (or several) fuel element(s) at a time. Fully converting a core to LEU fuel can take years, depending on the refueling schedule of the reactor.

8 This was RERTR’s first domestic conversion originally described as a “physics demonstration.” No HEU was shipped to FNR after December 1981. The time from the first insertion of an LEU fuel assembly to full conversion was 3 years.

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
×

reactors that still house fresh and spent HEU fuel, and the reduction in HEU usage. As noted previously, the shutdown of research reactors is often not associated with conversion activities. Although it is important to keep track of which reactors using HEU fuel remain operational, counting a shutdown reactor as progress toward conversion totals is not entirely accurate. A shutdown reactor does, however, count toward the M3 goal of HEU minimization, but only if all HEU is removed from the reactor site. In addition, recall that a small number of civilian research reactors are responsible for the majority of annual HEU consumption (Figures 2.3a,b).

Finding 14: There has been continuing progress in research reactor conversions and shutdowns since 2009. While the pace of reactor conversions has slowed, the pace of shutdowns has increased significantly.

Recommendation 6: The Material Management and Minimization’s Office of Conversion should augment its annual progress reports to include the following:

  1. Identification of the number of conversions in progress (i.e., with at least one low enriched uranium [LEU] assembly inserted into the core);
  2. Identification of the number of conversions completed, including the removal of highly enriched uranium (HEU) fresh and spent fuel from the site;
  3. Separate reporting of reactors that have fully converted to LEU from those that have been verified as shut down;
  4. Reduction of the aggregated inventory of HEU fuel at reactor sites (including shutdown reactors) attributable to the conversion program; and
  5. Reduction in the amount of weapon-grade HEU fuel shipped to HEU-fueled research reactors during the reporting period attributable to the conversion program.

The committee acknowledges the challenges posed by reporting detailed quantities of HEU stores. Therefore, this recommendation provides for flexibility in how amounts of HEU can be aggregated to allow public release.

ASSESSMENT OF DOE’S MANAGEMENT OF REACTOR CONVERSIONS AND HEU MINIMIZATION

The M3 Office of Conversion confronts several challenges that were not as apparent in the past (e.g., prior to the last Academies report). Managing them will require sustained political and financial support from multiple administrations, technical acumen, and careful management of the program.

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
×

The Nuclear Security Summits have been excellent venues for achieving international agreement for HEU elimination and commitments for reactor conversion (Landers, 2014). The last summit will be held in March 2016; it is not clear what, if anything, will take their place. The end of the summits suggests a diminishing of U.S. focus on HEU minimization efforts (Dickerson, 2014).

U.S.-Russia cooperation on reactor conversions has cooled after more than a decade of growing trust and collaboration (Madia, 2015; Roglans, 2015). This is clearly a blow to HEU minimization in light of the large number of remaining HEU-fueled research reactors in Russia and the mismatch in priorities that U.S. and Russian policy makers place on conversion.

There continue to be international dynamics that make engagement on research reactor conversion and HEU removal extremely difficult, if not impossible, in some countries. For example, the Democratic People’s Republic of Korea (DPRK) has steadfastly refused to engage with the international community regarding conversion of its civilian research reactors to the point that the experts participating in the joint International Atomic Energy Agency (IAEA)–Academies meeting (Appendix E) were unable to say definitively how many civilian research reactors are in the DPRK or what their condition may be. It is not possible to predict when engagement and conversion will be possible. Bluntly, most of the “easy” conversions have already been completed or are in progress.

In short, the pace of many international research reactor conversions depends on factors that are completely outside of the Office of Conversion’s control, for example, Russian cooperation. Timetables for reactor conversions and HEU removal that might have seemed reasonable not long ago now seem optimistic.

Finding 15: The Material Management and Minimization Office of Conversion’s current plan for conversion of all the civilian research reactors currently using highly enriched uranium (HEU) fuel by 2035 is highly uncertain, primarily because of nontechnical factors.

The M3 Office of Conversion’s program scope for conversion has nearly doubled since 2005 (see Figure 2.2). This increased scope requires additional funding, staffing, and/or time. The scope of the M3 Office of Conversion may be revisited based on the list of HEU-fueled civilian research reactors produced during the joint IAEA–Academies meeting. The program scope needs to be clearly defined, and the time lines and resources need to be aligned with that scope.

The M3 Office of Conversion has underestimated the challenges in developing and qualifying LEU fuels for high performance research reactors (HPRRs). This is the major reason why conversion schedules for HPRRs

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
×

have expanded so dramatically. The fundamental understanding of UMo monolithic and dispersion fuels has increased, and fuel developers are confident that upcoming irradiation tests will be passed (Meyer, 2014, 2015; Van den Berghe and Lemoine, 2014); however, it is still not assured that the fuel will be successfully qualified and the reactors converted. The Office of Conversion must better manage its technical risks if it expects to be successful in converting the remaining HPRRs, especially HFIR.

Managing Technical Risk

Two events in the mid-2000s resulted in a “program reset” in 2009 for GTRI’s Convert Program: UMo dispersion fuel irradiation failures (see Chapter 4) and technical disconnects between fuel design and manufacturing requirements. Following the irradiation test failures in 2006, efforts were initiated to better understand the material interactions leading to failures, and a new fuel system, UMo monolithic fuel, was explored. At the same time, the U.S. conversion program began to plan for manufacturing of the UMo monolithic fuel. Initial assessments identified potential manufacturing challenges. The program “reset” reassessed fuel development decisions and time lines with input from the fuel manufacturing and the fuel development technical leads. Time lines for fuel development and manufacturing were expanded after program managers recognized the extent of the technical challenges involved.

The largest technical obstacle to HPRR conversion is the qualification and fabrication of the very high-density UMo monolithic fuel (Rabin, 2015), especially for HFIR. The selection of fuel for converting USHPRRs evolved over time in response to failures of other fuel types. The first efforts at fuel development began with modifying existing dispersion fuels (the silicides), essentially by increasing their uranium density. When it was determined that the silicide fuels would not offer the densities needed by the HPRRs, the effort shifted to identifying fuel that was different in composition but structurally similar so that it could be manufactured in a similar manner to existing fuels. This effort resulted in the selection of high-density UMo dispersion alloys. However, this fuel proved incapable of providing the required uranium density for the USHPRRs. This drove fuel developers to another new fuel material with different fabrication and manufacturing requirements (i.e., very high-density UMo monolithic fuel fabricated by co-rolling; Robinson et al., 2013). By the time the UMo monolithic fuel was identified, the fuel development effort was significantly behind the original schedule. That left no time for exploration of alternative fuel formulations that have more suitable manufacturing characteristics. The current fuel development and fabrication programs are moving forward under tight deadlines with limited options to explore

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
×

alternative material or fabrication processes and little room for error (Burkes, 2015).

The full life cycle of the fuel, including manufacturing, processing of scrap, and disposition of spent fuel, was not seriously considered as the fuel formulation was finalized. The steady evolution of the fuel away from well-known materials and processes has resulted in a number of technical “surprises” that have required significant engineering advances to overcome (Van den Berghe at al., 2015; Meyer, 2015). The additional time to address these surprises has lengthened the time lines for converting the USHPRRs even further (see Chapter 2). The current program roadmap shows a critical pathway to completing conversion of the USHPRRs by 2032 (see Figure 4.9).

Addressing the remaining technical risks for the conversion program requires taking a broad, critical look at the entire fuel development, fabrication, and manufacturing process, up to and including reactor conversion and back-end processes for spent fuel and scrap material. The M3 Office of Conversion has instituted reviews of some aspects of fuel development and conversion to mitigate this risk. Individual teams are performing independent strategic, cost, and fuel development reviews.

A group of independent experts is performing the independent strategic review (ISR). The ISR has met twice since its formation in April 2013 and has reviewed the overall management of the conversion program and its pillars: fuel development, fuel fabrication, and conversion. The ISR group was not charged with evaluating the technical details of the conversion program; rather, it relies on the fuel development review team to provide technical review to guide its advice.

The ISR group supports the current approach for managing the program, noting that the program managers are flexible and open to change. However, the ISR group also identified the lack of a systems-level review and a slow response to technical issues (the ISR group noted that technical issues were often being overwhelmed by political and geopolitical challenges). The ISR group identified the long time line for conversion as the highest-risk item for the program because continued funding and administration support while stable for many years is not guaranteed (Madia, 2015; Marra, 2015).

The committee agreed with many of the ISR group’s conclusions. For example, the committee sees no immediate need for concern that support has waned but also acknowledges that the nature of the U.S. political system does not guarantee that strong support will continue indefinitely. The committee also found a rigorous, systematic review of the conversion program to be lacking. The lack of a systems approach to the identification and development of high-density UMo fuel has created technical and schedule challenges for the fuel fabrication and manufacturing efforts, as

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
×

discussed previously. Going forward, an integration of design, fabrication, and manufacturing efforts across the conversion program would reduce the risks associated with qualifying a new fuel that is acceptable for use in USHPRRs and also manufacturable, affordable, and amenable to back-end processes. There is evidence that the M3 Office of Conversion has increased its emphasis on this critical aspect of the effort by adding an “integration” pillar and a systems analyst to the program staff. However, work is still required to ensure that this systems-level thinking pervades the program. The committee was unable to assess how the additional integration pillar and the new systems analysis expertise are being applied, because these capabilities were recently added.9

The cost review was focused on methods and systems in place for estimating costs, and not specific cost estimates.10 It did not address estimates of the cost of converting HPRRs or LEU fuel. HPRR operators are extremely concerned about the cost of LEU fuel, but there is no credible estimate of such costs. The rough estimate of relative costs provided by Babcock and Wilcox Technologies (BWXT; see Table 4.2) assumes that the yield for LEU fuel assemblies will be 88 to 90 percent, which is the value achieved in the manufacture of HEU fuel assemblies. Given the dramatically different manufacturing processes that will be required for monolithic UMo fuel, this assumption strikes the committee as overly optimistic. There is a particular need for a rigorous review of LEU manufacturing costs.

The fuel development review is the only technical review in the conversion program of which the committee is aware. The members of the review team are reactor fuel experts (Hobbins, 2015). The membership of this group, while technically strong, has a close association with the GTRI/M3 Office of Conversion and its fuel development efforts. This gives the appearance that the fuel development technical review does not have the level of independence that would be most beneficial to the conversion program. Experts with no direct (past or present) ties to the fuel development program could provide more critical evaluations and generate broader thinking. Box 4.2 highlights similarities and differences between the European and U.S. fuel development and manufacturing programs. Technical reviews within the European program consist of expert groups that include U.S. fuel development experts.

The fuel development review focused only on the fuel development activities of the fuel program. The most recent reviews have focused on measurements of bond strength in monolithic fuel, residual stress in monolithic fuel plates, microstructure of as-fabricated and irradiated fuel, and

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9 A systems-level report on fuel-cycle back-end options was recently produced.

10 Scott Dam, chair of the cost review for the conversion program, written correspondence, dated March 12, 2015.

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
×

fuel specifications. The committee found this review to be valuable but insufficient by itself, because fuel is useful only if it can be fabricated reproducibly, manufactured affordably, used to convert research reactors, and processed as both scrap and spent fuel (Burkes, 2015). The lack of an independent technical review of each phase of the fuel development, fabrication, manufacturing, and utilization life cycle is a serious shortcoming in the management of the conversion program.

It is imperative to have external, independent technical review of both the details of each aspect of the effort separately and of the full spectrum of effort. The significant delays relative to previous timetables in the fuel development and qualification program that are now expected for project completion have arisen largely for technical reasons. Technical risks in such a complex project could be identified through the use of regular, independent, external technical peer review by appropriate groups of technical experts.11 This approach is part of the culture in other parts of DOE (e.g., in the Office of Science, especially for its construction projects) and generally works very well. Combined with execution of formal project management and the effective programmatic evaluation that the project has already successfully implemented through its independent strategic review process, such technical oversight will be essential for successful and timely conversion of USHPRRs.

Execution of a well-developed technical risk mitigation plan could likely have reduced the delays in developing and qualifying high-density UMo monolithic fuel. The M3 Office of Conversion has developed a risk mitigation plan12 that describes detailed processes for identifying and mitigating risks as well as roles and responsibilities of project participants. The program has also developed tables of risks that are tracked on a monthly basis according to a documented process. The plan seems reasonable and complete, but it must be executed conscientiously and with a healthy dose of critical, independent, and questioning thinking to be effective in mitigating risks in the conversion program.

Finding 16: There has been a lack of rigorous systems analyses of the U.S. conversion programs as evidenced, for example, by the lack of involvement by the fuel fabricators during fuel development. The lack of risk management within the program likely lengthened the fuel development schedule. The M3 Office of Conversion’s risk management

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11 For example, the HERACLES program has two levels of expert groups that guide management decisions through technical review; technical experts from the U.S. conversion program participate in these reviews. The committee is unaware of technical experts from HERACLES participating in M3 technical reviews.

12 The committee was provided with the August 2014 version of this plan.

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
×

and systems analysis programs are positive developments but are new and unproven.

As the fuel qualification effort, particularly the development of manufacturing processes, matures, it will be important to establish metrics to gauge progress against program milestones. Such metrics might include the numbers of fuel plates produced, yields, or amounts of scrap material produced (and reclaimed). These metrics could supplement the independent technical review that is currently used to keep the program on track.

Finding 17: The technical setbacks and increasingly longer time lines for the conversion of U.S. high performance research reactors emphasize the need to incorporate regular independent technical and programmatic evaluations into the Office of Conversion program manager’s decision-making process.

Finding 18: Review teams have been established by the M3 conversion program in recent years to guide program management decisions. However, the technical review of fuel development was not performed by a team with the appropriate independence and institutional diversity needed for critical evaluation. Technical review of other parts of the program, such as fuel fabrication, does not currently exist.

Recommendation 7: In depth independent technical review of each aspect of the fuel life cycle (from fuel development, fabrication, recycling, and spent fuel management), as well as integration of the technical components, should be conducted to ensure that the newly instituted risk and systems analysis capabilities within the Material Management and Minimization Office of Conversion develop into robust project and risk management. These reviews should be conducted by qualified, independent, and diverse external experts.

Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
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Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
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Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
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Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
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Suggested Citation:"6 Conversion Program: Status and Management." National Academies of Sciences, Engineering, and Medicine. 2016. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors. Washington, DC: The National Academies Press. doi: 10.17226/21818.
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The continued presence of highly enriched uranium (HEU) in civilian installations such as research reactors poses a threat to national and international security. Minimization, and ultimately elimination, of HEU in civilian research reactors worldwide has been a goal of U.S. policy and programs since 1978. Today, 74 civilian research reactors around the world, including 8 in the United States, use or are planning to use HEU fuel. Since the last National Academies of Sciences, Engineering, and Medicine report on this topic in 2009, 28 reactors have been either shut down or converted from HEU to low enriched uranium fuel. Despite this progress, the large number of remaining HEU-fueled reactors demonstrates that an HEU minimization program continues to be needed on a worldwide scale. Reducing the Use of Highly Enriched Uranium in Civilian Research Reactors assesses the status of and progress toward eliminating the worldwide use of HEU fuel in civilian research and test reactors.

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