[Federal Register Volume 85, Number 15 (Thursday, January 23, 2020)]
[Proposed Rules]
[Pages 3860-3867]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-01026]


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NUCLEAR REGULATORY COMMISSION

10 CFR Part 72

[Docket No. PRM-72-8; NRC-2018-0017]


Requirements for the Storage of Spent Nuclear Fuel

AGENCY: Nuclear Regulatory Commission.

ACTION: Petition for rulemaking; denial.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is denying a 
petition for rulemaking (PRM), submitted by Raymond Lutz and Citizens 
Oversight, Inc. (the petitioners), dated January 2, 2018. The 
petitioners requested that the NRC amend its regulations regarding 
spent nuclear fuel storage systems to embrace the Hardened Extended-
life Local Monitored Surface Storage (HELMS) approach and identified 
multiple revisions to accommodate such an approach. The NRC is denying 
the petition because the petitioners do not present information that 
supports the requested changes to the regulations or that provides 
substantial increase in the overall protection of occupational or 
public health and safety. The NRC's current regulations and oversight 
activities continue to provide for the adequate protection of public 
health and safety and to promote the common defense and security.

DATES: The docket for PRM-72-8 is closed on January 23, 2020.

ADDRESSES: Please refer to Docket ID NRC-2018-0017 when contacting the 
NRC about the availability of information for this action. You may 
obtain publicly-available information related to this action by any of 
the following methods:
     Federal Rulemaking Website: Go to https://www.regulations.gov and search for Docket ID NRC-2018-0017. Address 
questions about NRC dockets to Carol Gallagher; telephone: 301-415-
3463; email: [email protected]. For technical questions, contact 
the individuals listed in the FOR FURTHER INFORMATION CONTACT section 
of this document.
     NRC's Agencywide Documents Access and Management System 
(ADAMS): You may obtain publicly-available documents online in the 
ADAMS Public Documents collection at https://www.nrc.gov/reading-rm/adams.html. To begin the search, select ``Begin Web-based ADAMS 
Search.'' For problems with ADAMS, please contact the NRC's Public 
Document Room (PDR) reference staff at 1-800-397-4209, at 301-415-4737, 
or by email to [email protected]. For the convenience of the reader, 
instructions about obtaining materials referenced in this document are 
provided in the ``Availability of Documents'' section.
     NRC's PDR: You may examine and purchase copies of public 
documents at the NRC's PDR, Room O1-F21, One White Flint North, 11555 
Rockville Pike, Rockville, Maryland 20852.

FOR FURTHER INFORMATION CONTACT: Timothy McCartin, telephone: 301-415-
7099, email: [email protected], or Gregory R. Trussell, 
telephone: 301-415-6244, email: [email protected]. Both are 
staff of the Office of Nuclear Material Safety and Safeguards, the U.S. 
Nuclear Regulatory Commission, Washington, DC 20555-0001.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. The Petition
II. Public Comments on the Petition
III. Reasons for Denial
IV. Availability of Documents
V. Conclusion

I. The Petition

    Section 2.802 of title 10 of the Code of Federal Regulations (10 
CFR), ``Petition for rulemaking--requirements for filing,'' provides an 
opportunity for any interested person to petition the Commission to 
issue, amend, or rescind any regulation in 10 CFR chapter I. On January 
2, 2018, the NRC received a petition from Raymond Lutz and Citizens 
Oversight, Inc. The NRC

[[Page 3861]]

docketed this petition on January 22, 2018, and assigned it Docket No. 
PRM-72-8. The NRC published a notice of docketing and request for 
public comment on March 22, 2018 (83 FR 12504). The petitioners request 
that the NRC amend 10 CFR part 72, ``Licensing requirements for the 
independent storage of spent nuclear fuel, high-level radioactive 
waste, and reactor-related greater than Class C waste,'' to embrace the 
HELMS approach, for the long-term storage of spent nuclear fuel.
    The petitioners recommend a hardened storage system because they 
state that the current storage systems are not equipped to resist 
malicious attacks. The petitioners further state that the current 
storage casks will corrode and crack and are not designed for 
indefinite surface storage. However, the petitioners assert that spent 
nuclear fuel will continue to be stored on the surface for very long 
time periods, potentially indefinitely, due to the lack of a deep 
geologic repository for permanent disposal. The NRC regulations provide 
that storage casks can be initially licensed for up to 40 years with 
possible renewals of up to 40 years, with no restriction on the number 
of renewals. The petitioners assert this regulatory process creates an 
indefinite timeframe, which they contend requires a storage system 
designed for an extended life. For these reasons, the petitioners 
recommend that all spent fuel storage systems have a design life of 
1,000 years, which includes a ``passive life'' of 300 years. The 
petitioners also assert that spent nuclear fuel needs to be moved to 
local consolidated interim storage sites away from water resources and 
dense populations. Additionally, the petitioners assert that the 
storage casks need a more robust monitoring system, including 
continuous monitoring during the initial 40 years.
    The HELMS approach is discussed further in Section III, ``Reasons 
for Denial,'' of this document.

II. Public Comments on the Petition

    The notice of docketing of the PRM invited interested persons to 
submit comments. The comment period closed on June 5, 2018, and the NRC 
received 70 comment submissions from members of the public, interested 
stakeholders, and industry groups. The discussion that follows 
consolidates and summarizes the relevant issues. The public comments 
are available in their entirety at www.regulations.gov under Docket ID 
NRC-2018-0017. A list of the public comments and their respective ADAMS 
Accession numbers is included in Section IV, ``Availability of 
Documents,'' of this document.
    The NRC received 58 comment submissions in support of the petition. 
These commenters were opposed to indefinite storage, asserted that 
casks are too thin, and supported double-wall canisters. Additionally, 
many commenters supported the petitioners' recommendation for a 1,000-
year design life. Commenters stated that interim storage facilities can 
be maintained for longer time periods with periodic replacement of the 
casks and adequate resources and attention to maintaining the storage 
facilities. Some commenters stated that a HELMS approach would address 
imminent terrorist attacks as well as unpredictable events by moving 
the waste to a half-dozen interim storage sites away from coastal areas 
or waterways.
    The NRC received four comment submissions from stakeholders and 
industry groups that did not support the petition. In general, the 
commenters asserted the petition is without merit, the petitioners' 
suggestions are not supported by a technical basis, and costs were not 
considered. The commenters argued that existing regulations and 
oversight, including inspections, provide the necessary framework to 
ensure the safe storage of spent nuclear fuel. Additionally, the 
commenters stated that the petitioners disregarded the NRC's experience 
with spent fuel storage. One commenter noted that, in NRC's 2014 final 
rule on the continued storage of spent nuclear fuel (79 FR 56251; 
September 19, 2014), the Commission emphasized that the national policy 
remains to dispose of spent fuel in a geologic repository and that the 
petitioners did not provide a basis for revisiting the Commission's 
policy decisions. The commenters also claimed that the petition 
included factual inaccuracies; however, the commenters did not provide 
specific information that the NRC could evaluate.
    One commenter who opposed the petition noted that hardened onsite 
storage would further fortify the structures with mounds of concrete, 
steel, and gravel. This commenter believed that this would result in 
the permanent-storage of spent nuclear fuel at the facility.
    The NRC received a comment of general concern to stop the ``waste 
burial'' at San Onofre Nuclear Generating Station. The commenter stated 
that money was being put before public safety but did not provide 
specific information for the agency to evaluate.
    The NRC also received several comment submissions that were outside 
of the scope of this petition.

III. Reasons for Denial

A. General Discussion

    The petitioners assert a mismatch now exists between the NRC 
regulations for the storage of spent nuclear fuel in dry casks in 10 
CFR part 72 and the status for the disposal and storage of spent 
nuclear fuel today. The petitioners note that a geologic repository for 
permanent disposal of spent nuclear fuel does not exist. Additionally, 
the petitioners state that storage of spent nuclear fuel at nuclear 
plants for an indefinite period is allowed under the NRC's 
regulations.\1\ The petitioners request many revisions to the 10 CFR 
part 72 requirements and state these are needed to accommodate the 
indefinite surface storage of spent nuclear fuel.
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    \1\ The petitioners asserted that the NRC's 2014 final rule, 
``Continued Storage of Spent Nuclear Fuel,'' authorized indefinite 
storage. As part of the development of the final rule, the NRC 
prepared a generic environmental impact statement that analyzed the 
environmental impacts of continued storage and provides a regulatory 
basis for the rule. The final rule did not authorize the production 
or storage of spent fuel, nor did it amend or extend the term of any 
license.
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    Although the 10 CFR part 72 regulations were developed at a time 
when a geologic repository was expected to be operational in 1998, 
extensive work has been done since the initial development of the 
regulations to ensure that the continued storage of spent nuclear fuel 
is safe and secure. This work includes revisions to 10 CFR part 72 and 
the development of guidance documents. Additionally, the evaluation of 
operational data collected nationally and internationally demonstrates 
that the NRC's regulatory framework for the continued storage of spent 
nuclear fuel provides reasonable assurance of adequate protection of 
public health and safety. The Commission described the basis for the 
safety and security of continued storage most recently in the NRC's 
2014 final rule on continued storage and accompanying NUREG-2157, 
``Generic Environmental Impact Statement for Continued Storage of Spent 
Nuclear Fuel.'' In these two documents, the NRC discussed its current 
regulatory framework for the storage of spent nuclear fuel as a basis 
for the continued safe storage of spent nuclear fuel. The NRC explained 
that:
    1. Decades of operating experience and ongoing NRC inspections 
demonstrate that the reactor and independent spent fuel storage 
installation (ISFSI) licensees continue to meet their obligation to 
safely store spent fuel in accordance with the requirements of 10 CFR 
parts 50, 52, and 72.

[[Page 3862]]

    2. The NRC continues to improve its understanding of long-term dry 
storage issues and is separately examining the regulatory framework and 
potential technical issues related to extended storage and subsequent 
transportation of spent fuel for multiple ISFSI license renewal periods 
extending beyond 120 years.
    3. The NRC also is closely following Department of Energy and 
industry efforts to study the effects of storing high burn-up spent 
fuel in casks.
    4. If the NRC were to be informed of or to identify a concern with 
the safe storage of spent fuel, the NRC would evaluate the issue and 
take whatever action or change in its regulatory program is necessary 
to continue providing adequate protection of public health and safety 
and promoting the common defense and security.
    The NRC has determined that regulatory oversight will continue in a 
manner consistent with the NRC's regulatory actions and oversight in 
place today in order to provide for continued storage of spent fuel in 
a safe manner until the fuel can be safely disposed of in a repository.
    Since the publication of the 2014 final rule, the NRC has continued 
to evaluate issues associated with the storage of spent nuclear fuel in 
dry casks and has not identified any necessary changes to the 
regulations based on the concerns raised by the petitioners. 
Furthermore, the NRC routinely evaluates the safe storage of spent 
nuclear fuel through operating experience and inspection findings. If 
the NRC identified an area needing additional oversight, the NRC would 
revise the regulatory requirements. After consideration of the 
proposals presented by the petitioners, the rationale provided in the 
NRC's 2014 final rule, and the evaluations discussed in this document, 
the NRC finds the regulatory changes requested by the petitioners are 
not needed to provide reasonable assurance that continued storage of 
spent nuclear fuel in dry cask storage systems is safe and secure.

B. The HELMS Approach

    The petitioners describe a strategy for the storage of spent 
nuclear fuel and request changes to 10 CFR part 72 to implement a HELMS 
approach. Therefore, the NRC's evaluation of the petitioners' requests 
is structured according to this approach.
1. Hardened Storage
    The petitioners assert that ``hardened'' storage is needed to 
address concerns associated with safety (e.g., unpredictable natural 
events such as earthquakes) and security (e.g., terrorist activity).
Safety (Natural Events)
    The NRC's regulations in 10 CFR part 72 include both siting 
requirements (subpart E, Siting Evaluation Requirements) and design 
criteria (subpart F, General Design Criteria) that require an applicant 
to evaluate the impact of natural events on the safety of dry cask 
storage systems and facilities. In particular, 10 CFR 72.122 requires 
that natural phenomena (e.g., earthquakes, tornados, and floods) that 
exist or that could occur at a proposed site must be identified and 
assessed according to the potential to affect the safe operation of a 
dry cask storage system and facility. The applicant or licensee must 
assess the capabilities of the structures, systems, and components 
important to safety to withstand the effects of the severe natural 
phenomena and continue to perform their safety functions. For these 
reasons, the NRC finds its regulations in 10 CFR part 72 provide an 
adequate framework to evaluate the capabilities of dry cask storage 
systems and facilities to withstand a wide range of extreme natural 
events.
    The petitioners also request that the NRC revise its regulations to 
indicate that storage is preferable ``east of 104[deg] west longitude 
so as to avoid the region of high-seismic activity west of this line.'' 
The NRC finds that this specific revision is not necessary. The 
assessment of natural hazards required by 10 CFR part 72 provides data 
on natural events, such as earthquakes, that are used in the siting of 
dry cask storage facilities. The NRC regulations require assessment of 
the hazards, which takes into consideration the specific facility 
design and the magnitude of the seismic risk. This assessment 
incorporates an understanding of how structures, systems, and 
components relied on for safety are affected by the hazards for a 
specific site and design.
    The NRC is aware of the variability in the seismic risk across the 
United States and incorporates these data in its regulations; 10 CFR 
72.102 specifically identifies 104[deg] west longitude in the 
requirements for geological and seismological characteristics. 
Additionally, the NRC evaluated and revised the investigation of 
seismic hazards for a spent nuclear storage facility in the 2003 final 
rule, Geological and Seismological Characteristics for Siting and 
Design of Dry Cask Independent Spent Fuel Storage Installations and 
Monitored Retrievable Storage Installations (68 FR 54143; September 16, 
2003). The 2003 final rule revised 10 CFR part 72 to incorporate 
changes to: (1) Utilize the experience gained in applying the existing 
regulations and from recent seismic research; and (2) provide 
regulatory flexibility to incorporate state-of-the-art improvements in 
the geosciences and earthquake engineering into licensing actions. 
These revisions improved the evaluation of seismic hazards but did not 
categorically exclude regions solely on geographic location. The NRC's 
regulations recognize that geographic areas west of approximately 
104[deg] west longitude are known to have potential seismic activity 
and provide specific requirements for the evaluation of seismicity in 
these areas. The NRC, however, determined that the exclusion of storage 
of spent nuclear fuel west of approximately 104[deg] west longitude is 
unnecessary to ensure that seismic events are appropriately 
investigated in the safety evaluation of storage of spent nuclear fuel.
Security (Terrorist Attacks)
    The petitioners recommend that hardened storage such as ``an outer 
building of sufficient strength to resist terrorist attacks'' also 
should be considered to provide a measure of defense-in-depth.
    The NRC provides security requirements for physical protection for 
spent fuel storage and transportation in 10 CFR part 72, 10 CFR part 
73, ``Physical Protection of Plants and Materials,'' and orders that 
provide additional security measures. For example, the NRC's 
regulations at 10 CFR 73.51 include security measures to minimize the 
likelihood of a successful terrorist attack, including: (1) Spent 
nuclear fuel must be stored only within a protected area so that access 
requires passage through or penetration of two physical barriers, and 
one of the barriers is required to offer substantial penetration 
resistance; (2) the perimeter of the protected area must be subject to 
continual surveillance and be protected by an active intrusion alarm 
system; and (3) the primary alarm station must be located within a 
protected area and have bullet-resisting walls, doors, ceiling, and 
floor.
    Additionally, the NRC initiated several actions designed to provide 
high assurance that a terrorist attack would not lead to a significant 
radiological event at an ISFSI. These include: (1) Continual evaluation 
of the threat environment by the NRC, in coordination with the 
intelligence and law enforcement communities, which provides, in part, 
the basis for the protective measures currently required; (2) 
protective measures in place to

[[Page 3863]]

reduce the likelihood of an attack that could lead to a significant 
release of radiation; (3) the robust design of storage casks, which 
provides substantial resistance to penetration; and (4) NRC security 
assessments of the potential consequences of terrorist attacks against 
ISFSIs. Over the past 20 years, no known or suspected attempts have 
taken place to: (1) Sabotage or to steal radioactive material from 
storage casks at ISFSIs; or (2) directly attack an ISFSI. Nevertheless, 
the NRC is continually evaluating the threat environment to determine 
whether any specific threat to ISFSIs exists.
    The NRC conducted security assessments for ISFSIs using several 
storage cask designs that are representative of current NRC certified 
designs. The results of these security assessments contain sensitive 
unclassified information and therefore are not publicly available. 
Plausible threat scenarios considered in the generic security 
assessments for ISFSIs included a large aircraft impact similar in 
magnitude to the attacks of September 11, 2001, and ground assaults 
using expanded adversary characteristics consistent with the design 
basis threat for radiological sabotage for nuclear power plants. Based 
on these assessments, the NRC concluded there is no need for further 
security measures at ISFSIs beyond those currently required by 
regulation and imposed by orders issued after September 11, 2001. The 
post-9/11 orders are not publicly available because they contain 
safeguards information. Furthermore, the NRC is not aware of any threat 
analyses that support requirements for additional hardening of spent 
fuel casks.
2. Extended Life
    To plan for indefinite storage, the petitioners request that the 
regulations be revised to require that dry cask storage systems be 
designed for a ``design life'' of 1,000 years, which includes a 
``passive life'' of 300 years with a goal that during this period the 
storage system ``will remain safe, contained, and shielded'' without 
maintenance or other intervention. The petitioners describe a dual-wall 
container as one approach for extended dry cask storage.
    The petitioners recommend that several sections in 10 CFR part 72 
be changed to implement the 1,000-year design life. The petitioners 
suggest that a dual-wall container be required based, in part, on the 
petitioners' position that the single-wall canisters currently used in 
many storage system designs will inevitably be compromised due to 
cracking. However, the petitioners emphasize that the HELMS proposal 
does not rely on the adoption of this specific proposal, if the 
extended-life criterion is satisfied (Petition Attachment page 6).
    Under the current regulations, dry cask storage systems are 
designed as passive systems, which rely on natural air circulation for 
cooling, and are inherently robust, massive, and highly resistant to 
damage. The NRC regulations at 10 CFR 72.128 and 72.236 specify 
requirements for ensuring dry cask storage facilities and systems are 
safe and will remain safe under normal, off-normal, and accident 
conditions.
    The license terms for spent fuel storage systems must not exceed 40 
years, as specified at 10 CFR 72.42 for a storage installation and at 
10 CFR 72.238 for an initial certificate for spent fuel storage casks. 
However, a license or certificate may be renewed for a period not to 
exceed 40 years and multiple renewals may be requested. The NRC has 
determined that a 40-year licensing period, in conjunction with the 
slow degradation rates of spent fuel storage systems, provides 
reasonable assurance that significant storage, handling, and 
transportation issues do not arise during a single license period. 
Additionally, if information collected during a license period 
identifies emerging issues and concerns, there would be sufficient time 
to develop regulatory solutions and incorporate them into future 
licensing periods. The NRC requires that the collection of appropriate 
information and the implementation of aging management activities are 
part of license renewals. These include: (1) Time-limited aging 
analyses that demonstrate that the structures, systems, and components 
important to safety continue to perform their intended functions; and 
(2) aging management programs for specific issues known to be 
associated with aging, which could adversely affect structures, 
systems, and components important to safety.
    The NRC determined its regulatory framework provides reasonable 
assurance for the continued safe and secure storage of spent fuel. 
Since the publication of NRC's 2014 final rule on the continued storage 
of spent nuclear fuel (79 FR 56251; September 19, 2014) the NRC has 
issued guidance that defines acceptable approaches to manage aging 
during extended storage through inspections, monitoring activities, and 
preventive actions. Two of the NRC's guidance documents addressing 
aging management are: (1) NUREG-1927, Revision 1, ``Standard Review 
Plan for Renewal of Specific Licenses and Certificates of Compliance 
for Dry Storage of Spent Nuclear Fuel''; and (2) NUREG-2214, ``Managing 
Aging Processes in Storage (MAPS) Report.'' The Standard Review Plan, 
NUREG-1927, Revision 1, provides guidance for the staff's review of 
general information, scoping evaluation information, and aging 
management information in a renewal application. Specifically, the 
Standard Review Plan addresses the review of time-limited aging 
analyses and aging management programs to address issues associated 
with aging, including aging management programs for welded stainless 
steel canisters, reinforced concrete structures, and high burnup fuel. 
The MAPS report, NUREG-2214, provides a generic evaluation of aging 
mechanisms, which have the potential to undermine the ability of dry 
cask storage systems' structures, systems, and components to fulfill 
their important-to-safety functions. The MAPS report also updates the 
NRC's aging management program guidance and discusses additional aging 
management programs that were not described in NUREG-1927. For example, 
the MAPS report discusses a program for managing the aging of bolted 
cask storage systems, which is an alternative to welded canister-based 
designs.
    The NRC also developed a temporary instruction, NRC Temporary 
Instruction 2690/011, ``Review of Aging Management Programs at 
Independent Spent Fuel Storage Installations.'' The temporary 
instruction serves as an information-gathering activity and the 
resulting data will be used to develop a new NRC inspection procedure 
to evaluate licensees' performance of these aging management 
activities.
    The nuclear industry has recently contributed operational 
information, data, and proposals to address extended storage. This 
includes a system to collect and disseminate operating experience, for 
use by aging management programs at storage sites. The industry has 
also published guidance on developing aging management activities in 
license renewal applications. This guidance is entitled ``Format, 
Content and Implementation Guidance for Dry Cask Storage Operations-
Based Aging Management'' (NEI 14-03) and is being reviewed by the NRC 
for endorsement. The NEI 14-03 provides a broad framework for 
integrating feedback from dry cask storage operating experience, 
research, monitoring and inspections into the management of aging-
related degradation for structures, systems, and components at ISFSIs. 
Additionally, the Institute of Nuclear Power Operations

[[Page 3864]]

(INPO) implemented the Independent Spent Fuel Storage Installation 
Aging Management INPO Database that collects, aggregates, and shares 
aging-related operating information to inform the aging management 
programs of ISFSI licensees and certificate of compliance holders.
    In addition to the activities mentioned above that generically 
address extended storage, the NRC has undertaken research and guidance 
development on more focused aging issues. Two focus areas are high-
burnup fuel and stress corrosion cracking of spent fuel storage 
canisters.
    The NRC recognizes that the cladding for high-burnup spent nuclear 
fuel may be subject to aging mechanisms (e.g., hydride reorientation 
and creep) due to its service history (e.g., time, temperature, 
pressure) that could affect performance during handling, storage, and 
transportation of spent fuel. Since the publication of the NRC's 2014 
final rule on continued storage, the NRC continues to research the 
effects of extended storage of high-burnup spent nuclear fuel, as part 
of the NRC's effort to evaluate and update its regulations. In 2018, 
the NRC published for comment NUREG-2224, ``Dry Storage and 
Transportation of High Burnup Spent Nuclear Fuel.'' The NUREG-2224 
report presents an engineering assessment of a wide range of recent 
studies and activities evaluating the mechanical performance of high-
burnup spent nuclear fuel cladding. The studies evaluated in NUREG-2224 
examined specific aspects of storage and transportation of high-burnup 
spent nuclear fuel, including:
     A study on fatigue strength provides data to allow for 
more accurate assessments of the structural behavior of high-burnup 
spent nuclear fuel under normal conditions of transportation and 
hypothetical accident conditions, as well as dry storage system drop 
and tip-over events (NUREG/CR-7198, Revision 1);
     A study on how the characteristics of high-burnup spent 
nuclear fuel could affect the mechanisms by which spent nuclear fuel 
can breach the cladding and the amount of spent nuclear fuel that can 
be released from the failed fuel rods (NUREG/CR-7203); and
     Investigations of the fatigue and bending strength 
performance of high-burnup spent nuclear fuel cladding in as-irradiated 
and hydride-reoriented conditions (Wang et al.).
    Stress corrosion cracking of spent fuel storage canisters is 
another aspect of extended storage that has received significant NRC 
and stakeholder attention. The nuclear community has undertaken 
research and guidance development to understand this aging mechanism 
and to develop inspection approaches, including the creation of new 
rules for canister inspections in the American Society of Mechanical 
Engineers (ASME) Boiler and Pressure Vessel Code. The nuclear industry, 
Federal government, the Department of Energy national laboratories, and 
suppliers of spent fuel dry storage systems participate in the Extended 
Storage Collaboration Program (ESCP), which investigates aging effects 
and mitigation options for the extended storage and transportation of 
spent nuclear fuel. In 2015, the ESCP published, ``Susceptibility 
Assessment Criteria for Chloride-Induced Stress Corrosion Cracking of 
Welded Stainless Steel Canisters for Dry Cask Storage Systems.'' This 
document summarizes the major factors that affect the susceptibility of 
stainless steel dry storage canisters to atmospheric chloride-induced 
stress corrosion cracking and identifies which dry cask storage systems 
will most likely need inspections and enhanced monitoring programs to 
detect the potential for initiation and propagation of chloride-induced 
stress corrosion cracking. In 2017. the ESCP also published, ``Aging 
Management Guidance to Address Potential Chloride-Induced Stress 
Corrosion Cracking of Welded Stainless Steel Canisters.'' This document 
provides guidance and recommendations for the development of an aging 
management program to address the potential for chloride-induced stress 
corrosion cracking of austenitic stainless steel canisters, with an 
emphasis on evaluating and incorporating user-generated information and 
operational experience, as they become available.
    Significant work continues both nationally and internationally to 
enhance the understanding of the degradation of dry cask storage 
systems--including stress corrosion cracking of spent fuel storage 
containers--as well as the inspection and collection of operating 
experience. These efforts are consistent with the NRC's regulatory 
approach to enhance understanding of potential degradation mechanisms 
associated with dry cask storage systems. This enhanced understanding 
assists the NRC with identifying potential concerns with the safe 
storage of the spent fuel, with evaluating any such issues identified, 
and taking necessary actions, up to and including issuing orders or 
revising its regulations.
    Although the petitioners request a long-lived waste package design 
with the goal of no maintenance or other interventions for the initial 
300 years, the petitioners request that the NRC retain its current 
license term of up to 40 years for a certificate of compliance or 
license in 10 CFR part 72. The petitioners express the opinion that dry 
cask storage should be enhanced, but do not provide information to 
support the claim that the NRC's regulatory approach for dry cask 
storage is not safe and secure.
    The NRC's current practice of renewing a certificate of compliance 
or a license for no more than 40 years allows for new technical and 
scientific information and operational data to be considered by the NRC 
when it decides whether to approve the renewal of a license or 
certificate of compliance. The NRC's licensing requirements in 10 CFR 
part 72 provide for a robust storage system design. However, the 40-
year term does not mean a dry storage cask is no longer safe at the end 
of the licensing period. The NRC has determined that to renew a spent 
fuel storage cask design, the certificate holder or licensee must 
assess the need for maintenance and/or monitoring in the future. In 
NUREG-2157, the NRC evaluated environmental impacts by assuming ``the 
replacement of dry casks after 100 years of service life; however, 
actual replacement times will depend on actual degradation observed 
during ongoing regulatory oversight for maintaining safety during 
continued storage. Scientific studies and operational experience to 
date do not preclude a dry cask service life longer than 100 years'' 
(NUREG-2157; page B-18). The NRC continues to evaluate aging management 
programs and to monitor dry cask storage in order to update its 
service-life assumptions and to identify and address circumstances that 
could require repackaging of spent fuel earlier than anticipated.
    If the repackaging of spent nuclear fuel becomes necessary, the 
regulations in 10 CFR 72.236(h) require that spent fuel storage systems 
be compatible with wet or dry spent fuel loading and unloading 
facilities. If a storage canister needs to be opened, the licensee must 
keep radioactive material confined, maintain the fuel in an arrangement 
that does not cause a nuclear chain reaction, and shield the workers 
and the public from radiation. The industry has decades of operating 
experience with wet transfer of new fuel and spent fuel, which involves 
spent fuel handling equipment and procedures that are similar to those 
used in a dry transfer system. The NRC concluded the safe transfer of 
spent fuel will occur regardless of whether a site maintains a

[[Page 3865]]

spent fuel pool (see Section 4.17.2 of NUREG-2157). Transfer operations 
at existing facilities routinely maintain public and occupational doses 
that are well within existing limits.
    The NRC also notes the following design and operational 
characteristics of spent fuel storage systems continue to support safe 
storage of spent fuel:
     Dry cask storage systems are designed as passive systems 
that rely on natural air circulation for cooling and they are 
inherently robust, massive, and highly resistant to damage.
     Dry cask storage facilities and systems are designed to 
remain safe under normal, off-normal, and accident conditions.
     The degradation rates of spent fuel storage systems are 
sufficiently slow that significant storage, handling, and 
transportation issues are not expected to develop during a single 40-
year license period.
     If information collected during a license period indicates 
any emerging issues and concerns, there would be sufficient time to 
develop technical and regulatory solutions and incorporate them into 
future licensing periods.
    In summary, the NRC's regulatory approach uses the operational 
experience and scientific information collected and assessed during 
licensed operation to ensure the safe storage of spent nuclear fuel. 
The petitioners' proposal to specify a 1000-year lifetime for a storage 
system is unnecessary, arbitrary, and offers no commensurate benefit to 
public health and safety when compared with the NRC's current approach. 
The NRC's current regulatory framework requires a re-evaluation be 
conducted at least every 40 years to determine the continued safety of 
a dry cask storage system and to assess the need for maintenance and/or 
monitoring in the future. The technical arguments provided by the 
petitioners do not raise concerns that are not addressed by the NRC in 
both regulations and NUREG-2157. The NRC finds the recommended 1,000-
year design life for a storage canister is not necessary to maintain 
the continued safe storage of spent nuclear fuel, consistent with the 
NRC regulations.
    The NRC concludes that its current regulations at 10 CFR part 72 
provide adequate protection of the public health and safety without the 
need for an extended design life as proposed by the petitioners.
3. Local Siting
    The petitioners assert that spent fuel should be consolidated at a 
limited number of local sites, which according to the petitioners means 
locating a consolidated storage site ``near the source of the waste.'' 
The petitioners request the NRC's regulations be revised to restrict 
the siting of consolidated storage installations to: (1) At least 5 
miles from any ocean, bay, river, lake, or other important water 
resource; (2) at least 300 feet above sea level if it is within 30 
miles of any ocean; (3) at least 15 miles away from the boundary of any 
city, town, or other population and at least 5 miles from residential 
properties; (4) at least 5 miles from any major road, railroad, 
waterway, or industrial area; and (5) preferably east of 104[deg] west 
longitude to avoid a region of high seismic activity.
    The NRC's regulations in 10 CFR part 72 require that dry cask 
storage systems be compatible with the local geographical and 
environmental characteristics where the storage facility is located. In 
particular, the structures, systems, and components important to safety 
must be designed to: (1) Be compatible with site characteristics and 
environmental conditions associated with normal operations, 
maintenance, and testing; (2) withstand the effects of natural 
phenomena such as earthquakes, tornadoes, and floods; and (3) consider 
the most severe natural phenomena reported for the site and surrounding 
area, with appropriate margins to take into account the limitations of 
the data and the period of time in which the data have accumulated. 
Additionally, an applicant must demonstrate that individual dose limits 
will be met for normal operations (10 CFR 72.104) and accident 
conditions (10 CFR 72.106). These public dose limits take into 
consideration local characteristics, such as the location of nearby 
residents and transportation routes that traverse the controlled area 
of the facility.
    The NRC concludes its regulatory requirements for the safe storage 
of dry spent fuel at a specific location provide reasonable assurance 
of adequate protection of public health and safety. A license 
application for spent fuel storage evaluates the relevant hazards, 
conditions, and characteristics for a specific site in a safety 
evaluation report. The NRC finds the specific siting criteria suggested 
by the petitioners are unnecessary.
    Chloride-induced stress corrosion cracking provides an example of 
how site-specific concerns are evaluated by the NRC. The petitioners 
cite this cracking phenomenon as being an unavoidable degradation of 
stainless steel canisters exposed to outside air. The petitioners 
request dual-wall containers, or another approach, be adopted to 
prevent a radiation release to the public and environment during 
extended storage. Areas near salt water bodies with chloride-containing 
salts at elevated levels may have increased potential for chloride-
induced stress corrosion cracking of canisters. The NRC conducted 
testing to determine the conditions under which welded stainless steel 
canisters may be susceptible to stress corrosion cracking, including 
that caused by chlorides. The test results were published in two 
publicly-available reports: (1) NUREG/CR-7030, ``Atmospheric Stress 
Corrosion Cracking Susceptibility of Welded and Unwelded 304, 304L, and 
316L Austenitic Stainless Steels Commonly Used for Dry Cask Storage 
Containers Exposed to Marine Environments'' (October 2010); and (2) 
NUREG/CR-7170, ``Assessment of Stress Corrosion Cracking Susceptibility 
for Austenitic Stainless Steels Exposed to Atmospheric Chloride and 
Non-Chloride Salts'' (February 2014).
    The NUREG/CR-7030 report documents the NRC's evaluation of the 
stress corrosion cracking susceptibility of welded and unwelded 
austenitic stainless steels that are commonly used in dry storage 
systems in humid, chloride-rich environments. The test results reported 
in NUREG/CR-7030 indicate that chloride-induced stress corrosion 
cracking is highly dependent on the concentration of deposited sea 
salt, residual stress, cask temperature, and the relative humidity of 
the surrounding environment. The report recommends methods for 
determining salt deposition rates on the stainless steel canisters 
currently used in dry storage systems. The NRC assessed stress 
corrosion cracking susceptibility for austenitic stainless steels 
exposed to atmospheric chloride and non-chloride salts to determine the 
conditions under which dry storage canisters may be susceptible to 
stress corrosion cracking. These findings were presented in NUREG/CR-
7170. Additional testing recommended in NUREG/CR-7170 is currently 
being undertaken at national laboratories and universities under the 
ESCP. The NRC will use the results of these additional studies to 
evaluate the adequacy of siting requirements. However, to date, the NRC 
has not identified information indicating the current siting 
requirements are inadequate.
    The NRC concludes that its regulatory requirements for the safe 
storage of dry spent fuel at a specific location provide reasonable 
assurance of adequate protection of public health and safety. A 
licensee applying for approval of a spent fuel storage facility must 
evaluate the relevant hazards, conditions, and characteristics for a 
specific site in a

[[Page 3866]]

safety analysis report. A licensee must demonstrate that the facility 
will meet the safety limits for the release of radioactive materials in 
effluents and dose limits accounting for site characteristics, such as 
seismic hazards, the local population, tsunamis, and floods. Therefore, 
the NRC concludes it is not necessary to incorporate the petiitioners' 
proposed additional siting requirements into NRC's regulations.
4. Monitoring
    The petitioners request that continuous monitoring be required 
during the initial licensing period of up to 40 years, to determine 
when corrective action would be needed. The petitioners suggest that 
periodic monitoring would be required after this initial period.
    The NRC's regulations provide robust inspection and monitoring 
procedures for identifying conditions that could undermine safety. 
Additionally, the NRC's regulatory guidance assists licensees in 
meeting the requirements. The regulations at 10 CFR 72.44(c)(1)-(3) 
require that a licensee provide the surveillance requirements for 
inspecting and monitoring stored waste and for maintaining the 
integrity of required systems and components of an ISFSI in its 
technical specifications. The regulations at 10 CFR 72.122(h)(4) 
require that licensees be capable of monitoring spent fuel to identify 
concerns and take corrective actions as necessary to maintain safe 
storage conditions.
    The NRC is evaluating licensees' aging management programs against 
NRC Temporary Instruction 2690/011, ``Review of Aging Management 
Programs at Independent Spent Fuel Storage Installations,'' as part of 
its oversight of renewed licenses and certificates of compliance. The 
NRC uses the inspection process to determine whether licensees have 
adequate processes or procedures planned or in place to implement 
approved aging management programs consistent with the requirements of 
10 CFR part 72, and as provided in renewed ISFSI licenses and renewed 
certificates of compliance for casks. The temporary instruction 
includes a comprehensive evaluation of aging management programs, 
including the licensees' inspection and monitoring methods and 
techniques, and the frequency, sample size, data collection, and timing 
of licensee inspections.
    Furthermore, NUREG-2157 summarizes technical information supporting 
low degradation rates of spent fuel in dry cask storage systems and 
concludes that dry cask storage systems will provide adequate 
protection for periods well beyond a 40-year license period. The NRC 
stated that scientific ``studies and operational experience to date do 
not preclude a dry cask service life longer than 100 years'' (see 
NUREG-2157, page B-18). Additionally, dry cask storage systems rely on 
passive structures, systems, and components to maintain safety and have 
no active or moving parts during storage. The 40-year license period is 
sufficiently short and the degradation of storage system materials is 
sufficiently slow that significant storage, handling, and 
transportation issues are not expected to arise during a single license 
period, and if information collected during a license period identifies 
emerging issues and concerns, there would be sufficient time to develop 
regulatory solutions and incorporate them into future licensing periods 
(NUREG-2157, Appendix B). Therefore, the NRC does not require 
continuous monitoring.
    The NRC's regulations in 10 CFR part 72 provide the licensee 
flexibility in designing the monitoring program appropriate to its 
facility; however, the NRC inspects the monitoring and aging management 
programs to verify compliance with the regulations. Specifically, the 
NRC verifies through inspection that the functions of the structures, 
systems, and components important to safety are maintained throughout 
the period of extended operation. The NRC is not aware of technical 
information supporting the need for continuous monitoring of ISFSI 
systems, and the petitioners did not provide any such support.
5. Surface Storage
    The petitioners assert that the NRC and the public should embrace 
surface storage of spent nuclear fuel and should plan to store it 
safely, passively, and indefinitely on the surface because that is how 
waste is currently stored. This assertion does not involve a proposed 
change to the existing regulations.

C. Summary

    The NRC maintains that a strong regulatory framework including both 
regulatory oversight and licensee compliance is important to the 
continued safe storage of spent fuel. The NRC's regulatory framework 
for spent fuel storage is supported by well-developed regulatory 
guidance; voluntary domestic and international consensus standards; 
research and analytical studies; and processes for implementing 
licensing reviews, inspection programs, and enforcement oversight 
(NUREG-2157, page B-33). The technical information and operational 
experience collected and evaluated both internationally and nationally 
on dry cask storage continues to support the adequacy of 10 CFR part 72 
to provide reasonable assurance of adequate protection of public health 
and safety and to promote the common defense and security.
IV. Availability of Documents
    The documents identified in the following table are available to 
interested persons through one or more of the following methods, as 
indicated.

 
----------------------------------------------------------------------------------------------------------------
                                                                                Adams Accession No. or Federal
               Document                                 Date                     Register citation or website
----------------------------------------------------------------------------------------------------------------
Petition for Rulemaking (PRM-72-8)....  January 2, 2018.....................  ML18022B207.
Requirements for the Indefinite         March 22, 2018......................  83 FR 12504.
 Storage of Spent Nuclear Fuel,
 Petition for Rulemaking; Notice of
 Docketing and Request for Comment.
Public Commenters List................  May 9, 2019.........................  ML19137A265.
Continued Storage of Spent Nuclear      September 19, 2014..................  79 FR 56238.
 Fuel; Final Rule.
NUREG-2157, ``Generic Environmental     September 2014......................  ML14196A105 (Vol. 1), ML14196A107
 Impact Statement for Continued                                                (Vol. 2), Also ML14198A440
 Storage of Spent Nuclear Fuel''.                                              (Package).
Geological and Seismological            September 16, 2003..................  68 FR 54143.
 Characteristics for Siting and Design
 of Dry Cask Independent Spent Fuel
 Storage Installations and Monitored
 Retrievable Storage Installations;
 Final Rule.

[[Page 3867]]

 
NUREG-1927, Revision 1, ``Standard      June 2016...........................  ML16179A148.
 Review Plan for Renewal of Specific
 Licenses and Certificates of
 Compliance for Dry Storage of Spent
 Nuclear Fuel''.
NUREG-2214, ``Managing Aging Processes  October 2017........................  ML19214A111.
 in Storage (MAPS) Report''.
NRC Temporary Instruction 2690/011,     January 2018........................  ML17167A268.
 ``Review of Aging Management Programs
 at Independent Spent Fuel Storage
 Installations''.
Nuclear Energy Institute NEI 14-03,     December 2016.......................  ML16356A210.
 Revision 2, ``Format, Content and
 Implementation Guidance for Dry Cask
 Storage Operations-Based Aging
 Management''.
NUREG-2224, ``Dry Storage and           July 2018...........................  ML18214A132.
 Transportation of High Burnup Spent
 Nuclear Fuel'' (Draft for Comment).
NUREG/CR-7198, Revision 1,              October 2017........................  ML17292B057.
 ``Mechanical Fatigue Testing of High-
 Burnup Fuel for Transportation
 Applications''.
NUREG/CR-7203, ``A Quantitative Impact  September 2015......................  ML15266A413.
 Assessment of Hypothetical Spent Fuel
 Reconfiguration in Spent Fuel Storage
 Casks and Transportation Packages''.
Oak Ridge National Laboratory; Wang,    September 2016......................  ORNL/SR-2016/424, Available at:
 J.-A., H. Wang, H. Jiang, Y. Yan,                                             https://www.energy.gov/sites/prod/
 B.B. Bevard, J.M. Scaglione; ``FY                                             files/2017/02/f34/
 2016 Status Report: Documentation of                                          10Documentation%20DataCollectCIRF
 All CIRFT Data including Hydride                                              T%20TestsRodEndsHydrideReorTest.p
 Reorientation Tests''.                                                        df.
Electric Power Research Institute,      September 2015......................  EPRI-3002005371. The EPRI report
 ``Susceptibility Assessment Criteria                                          is publicly available at the
 for Chloride-Induced Stress Corrosion                                         www.epri.com website.
 Cracking (CISCC) of Welded Stainless
 Steel Canisters for Dry Cask Storage
 Systems''.
Electric Power Research Institute,      March 2017..........................  EPRI-3002008193. The EPRI report
 ``Aging Management Guidance to                                                is publicly available at the
 Address Potential Chloride-Induced                                            www.epri.com website.
 Stress Corrosion Cracking of Welded
 Stainless Steel Canisters''.
NUREG/CR-7030, ``Atmospheric Stress     October 2010........................  ML103120081.
 Corrosion Cracking Susceptibility of
 Welded and Unwelded 304, 304L, and
 316L Austenitic Stainless Steels
 Commonly Used for Dry Cask Storage
 Containers Exposed to Marine
 Environments''.
NUREG/CR-7170, ``Assessment of Stress   February 2014.......................  ML14051A417.
 Corrosion Cracking Susceptibility for
 Austenitic Stainless Steels Exposed
 to Atmospheric Chloride and Non-
 Chloride Salts''.
NUREG-1949, ``Safety Evaluation Report  January 2015........................  ML15022A146.
 Related to Disposal of High-Level
 Radioactive Wastes in a Geologic
 Repository at Yucca Mountain,
 Nevada,'' Volume 2: Repository Safety
 Before Permanent Closure.
----------------------------------------------------------------------------------------------------------------

V. Conclusion

    The NRC determined that the petitioners do not present information 
that supports the requested changes to the regulations or provides 
substantial increase in the overall protection of occupational or 
public health and safety. The NRC's current regulations continue to 
provide for the adequate protection of public health and safety and to 
promote the common defense and security.
    For the reasons cited in Section III of this document, the NRC is 
denying PRM-72-8.

    Dated at Rockville, Maryland, this 16th day of January 2020.

    For the Nuclear Regulatory Commission.
Annette L. Vietti-Cook,
Secretary of the Commission.
[FR Doc. 2020-01026 Filed 1-22-20; 8:45 am]
BILLING CODE 7590-01-P