[Federal Register Volume 73, Number 154 (Friday, August 8, 2008)]
[Proposed Rules]
[Pages 46204-46213]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-18291]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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Federal Register / Vol. 73, No. 154 / Friday, August 8, 2008 /
Proposed Rules
[[Page 46204]]
NUCLEAR REGULATORY COMMISSION
10 CFR Part 51
[Docket No. PRM-51-10, NRC-2006-0022 and Docket No. PRM-51-12, NRC-
2007-0019]
The Attorney General of Commonwealth of Massachusetts, The
Attorney General of California; Denial of Petitions for Rulemaking
AGENCY: Nuclear Regulatory Commission (NRC).
ACTION: Petition for rulemaking; denial.
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SUMMARY: The NRC is denying two petitions for rulemaking (PRM), one
filed by the Attorney General of the Commonwealth of Massachusetts
(Massachusetts AG) and the other filed by the Attorney General for the
State of California (California AG), presenting nearly identical issues
and requests for rulemaking concerning the environmental impacts of the
high-density storage of spent nuclear fuel in large water pools, known
as spent fuel pools (SFPs). The Petitioners asserted that ``new and
significant information'' shows that the NRC incorrectly characterized
the environmental impacts of high-density spent fuel storage as
``insignificant'' in its National Environmental Policy Act (NEPA)
generic environmental impact statement (EIS) for the renewal of nuclear
power plant licenses. Specifically, the Petitioners asserted that spent
fuel stored in high-density SFPs is more vulnerable to a zirconium fire
than the NRC concluded in its NEPA analysis.
ADDRESSES: You can access publicly available documents related to these
petitions for rulemaking using the following methods:
Federal e-Rulemaking Portal: Go to http://www.regulations.gov and
search for documents filed under Docket ID [NRC-2006-0022] (PRM-51-10),
and [NRC-2007-0019] (PRM-51-12).
NRC's Public Document Room (PDR): The public may examine and have
copied for a fee publicly available documents at the NRC's PDR, Public
File Area O1 F21, One White Flint North, 11555 Rockville Pike,
Rockville, Maryland.
NRC's Agencywide Documents Access and Management System (ADAMS):
Publicly available documents created or received at the NRC are
available electronically at the NRC's electronic Reading Room at http://www.nrc.gov/reading-rm/adams.html. From this page, the public can gain
entry into ADAMS, which provides text and image files of NRC's public
documents. If you do not have access to ADAMS or if there are problems
in accessing the documents located in ADAMS, contact the NRC PDR
reference staff at 1-899-397-4209, 301-415-4737, or by e-mail to
[email protected].
FOR FURTHER INFORMATION CONTACT: L. Mark Padovan, Office of Nuclear
Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC
20555-0001, telephone (301) 415-1423, e-mail [email protected].
SUPPLEMENTARY INFORMATION:
I. Background
II. Petitioners' Requests
III. Public Comments
IV. NEPA and NUREG-1437
V. Reasons for Denial--General
A. Spent Fuel Pools
B. Physical Security
C. Very Low Risk
VI. Reasons for Denial--NRC Responses to Petitioners' Assertions
A. New and Significant Information
B. Spent Fuel Assemblies Will Burn if Uncovered
1. Heat Transfer Mechanisms
2. Partial Drain-Down
3. License Amendments
C. Fuel Will Burn Regardless of its Age
D. SFP Zirconium Fire Will Propagate
E. SFP Zirconium Fire May Be Catastrophic
1. Not New and Significant Information; Very Low Probability
2. Shearon Harris Atomic Safety and Licensing Board Panel
(ASLBP) Proceeding
3. SFP Zirconium Fire Does Not Qualify As a DBA
F. Intentional Attack on a SFP is ``Reasonably Foreseeable''
1. NAS Report
2. Ninth Circuit Decision
G. SFP Zirconium Fire Should be Considered within the Analysis
of SAMAs
VII. Denial of Petitions
I. Background
The NRC received two PRMs requesting that Title 10 of the Code of
Federal Regulations (10 CFR), Part 51, be amended. The Massachusetts AG
filed its petition on August 25, 2006 (docketed by the NRC as PRM-51-
10). The NRC published a notice of receipt and request for public
comment in the Federal Register on November 1, 2006 (71 FR 64169). The
California AG filed its petition on March 16, 2007 (docketed by the NRC
as PRM-51-12). PRM-51-12 incorporates by reference the facts and legal
arguments set forth in PRM-51-10. The NRC published a notice of receipt
and request for public comment on PRM-51-12 in the Federal Register on
May 14, 2007 (72 FR 27068). The California AG filed an amended petition
(treated by the NRC as a supplement to PRM 51-12) on September 19,
2007, to clarify its rulemaking request. The NRC published a notice of
receipt for the supplemental petition in the Federal Register on
November 14, 2007 (72 FR 64003). Because of the similarities of PRM-51-
10 and PRM-51-12, the NRC evaluated the two petitions together.
The Petitioners asserted the following in their petitions:
1. ``New and significant information'' shows that the NRC
incorrectly characterized the environmental impacts of high-density
spent fuel storage as ``insignificant'' in the NRC's NUREG-1437,
Generic Environmental Impact Statement for License Renewal of Nuclear
Plants, May 1996. Specifically, the Petitioners asserted that an
accident or a malicious act, such as a terrorist attack, could result
in an SFP being drained, either partially or completely, of its cooling
water. The Petitioners further asserted that this drainage would then
cause the stored spent fuel assemblies to heat up and then ignite, with
the resulting zirconium fire releasing a substantial amount of
radioactive material into the environment.
2. The bases of the ``new and significant information'' are the
following:
a. NUREG-1738, Technical Study of the Spent Fuel Pool Accident Risk
at Decommissioning Nuclear Power Plants, January 2001
b. National Academy of Sciences Committee on the Safety and
Security of Commercial Spent Nuclear Fuel Storage, Safety and Security
of Commercial
[[Page 46205]]
Spent Nuclear Fuel Storage (National Academies Press: 2006) (NAS
Report)
c. Gordon R. Thompson, ``Risks and Risk-Reducing Options Associated
with Pool Storage of Spent Nuclear Fuel at the Pilgrim and Vermont
Yankee Nuclear Power Plants,'' May 25, 2006 (Thompson Report)
3. Specifically, the Petitioners asserted that the ``new and
significant'' information shows the following:
a. The fuel will burn if the water level in an SFP drops to the
point where the tops of the fuel assemblies are uncovered (complete or
partial water loss resulting from SFP drainage being caused by either
an accident or terrorist attack).
b. The fuel will burn regardless of its age.
c. The zirconium fire will propagate to other assemblies in the
pool.
d. The zirconium fire may be catastrophic.
e. A severe accident caused by an intentional attack on a nuclear
power plant SFP is ``reasonably foreseeable.''
The Petitioners also asserted that new and significant information
shows that the radiological risk of a zirconium fire in a high-density
SFP at an operating nuclear power plant can be comparable to, or
greater than, the risk of a core-degradation event of non-malicious
origin (i.e., a ``severe accident'') at the plant's reactor.
Consequently, the Petitioners asserted that SFP fires must be
considered within the body of severe accident mitigation alternatives
(SAMAs).
II. Petitioners' Requests
PRM-51-10 requested that the NRC take the following actions:
1. Consider new and significant information showing that the NRC's
characterization of the environmental impacts of spent fuel storage as
insignificant in NUREG-1437 is incorrect.
2. Revoke the regulations which codify that incorrect conclusion
and excuse consideration of spent fuel storage impacts in NEPA
decision-making documents, namely, 10 CFR 51.53(c)(2), 51.95(c) and
Table B-1, ``Summary of Findings on NEPA Issues for License Renewal of
Nuclear Power Plants,'' of appendix B to subpart A of 10 CFR Part 51.
Further, revoke 10 CFR 51.23(a) and (b), 51.30(b), 51.53, 51.61, and
51.80(b) to the extent that these regulations find, imply, or assume
that environmental impacts of high-density pool storage are
insignificant, and therefore need not be considered in any plant-
specific NEPA analysis.
3. Issue a generic determination that the environmental impacts of
high-density pool storage of spent fuel are significant.
4. Require that any NRC licensing decision that approves high-
density pool storage of spent fuel at a nuclear power plant, or any
other facility, must be accompanied by a plant-specific EIS that
addresses the environmental impacts of high-density pool storage of
spent fuel at that nuclear plant and a reasonable array of alternatives
for avoiding or mitigating those impacts.
5. Amend its regulations to require that SAMAs that must be
discussed in utility company environmental reports (ERs) and NRC
supplemental EISs for individual plants under 10 CFR 51.53(c)(3)(ii)(L)
and Table B-1 of appendix B to subpart A of 10 CFR part 51
(``Postulated Accidents: Severe Accidents'') must include alternatives
to avoid, or mitigate, the impacts of high-density pool zirconium
fires.
PRM-51-12 incorporates by reference PRM-51-10. PRM-51-12 requested
that the NRC take the following actions:
1. Rescind all NRC regulations found in 10 CFR part 51 that imply,
find, or determine that the potential environmental effects of high-
density pool storage of spent nuclear fuel are not significant for
purposes of NEPA and NEPA analysis.
2. Adopt, and issue, a generic determination that approval of such
storage at a nuclear power plant, or any other facility, does
constitute a major federal action that may have a significant effect on
the human environment.
3. Require that no NRC licensing decision that approves high-
density pool storage of spent nuclear fuel at a nuclear power plant, or
other storage facility, may issue without the prior adoption and
certification of an EIS that complies with NEPA in all respects,
including full identification, analysis, and disclosure of the
potential environmental effects of such storage, including the
potential for accidental or deliberately caused release of radioactive
products to the environment, whether by accident or through acts of
terrorism, as well as full and adequate discussion of potential
mitigation for such effects, and full discussion of an adequate array
of alternatives to the proposed storage project.
III. Public Comments
The NRC's notice of receipt and request for public comment invited
interested persons to submit comments. The comment period for PRM 51-10
originally closed on January 16, 2007, but was extended through March
19, 2007. The public comment period for PRM 51-12 closed on July 30,
2007. Accordingly, the NRC considered comments received on both
petitions through the end of July 2007. The NRC received 1,676 public
comments, with 1,602 of these being nearly identical form e-mail
comments supporting the petitions. Sixty-nine other comments also
support the petitions. These comments were submitted by States, private
organizations, and members of the U.S. Congress. Two letters from the
Nuclear Energy Institute (NEI) oppose the petitions, and three nuclear
industry comments endorse NEI's comments.
In general, the comments supporting the petitions focused on the
following main elements of the petitions:
NRC should evaluate the environmental impacts (large
radioactive releases and contamination of vast areas) of severe
accidents and intentional attacks on high-density SFP storage in its
licensing decisions (NEPA analysis).
The 2006 decision of the United States Court of Appeals
for the Ninth Circuit, San Luis Obispo Mothers for Peace v. NRC, 449
F.3d 1016 (9th Cir. 2006), cert. denied 127 S. Ct. 1124 (2007),
concluded that the NRC must evaluate the environmental impacts of a
terrorist attack on SFP storage in its licensing decisions.
NRC's claim that the likelihood of a SFP zirconium fire is
remote is incorrect. Partial loss of water in an SFP could lead to a
zirconium fire and release radioactivity to the environment.
NRC's characterization of the environmental impacts of
high-density SFP storage as ``insignificant'' in NUREG-1437 is
incorrect, and the NRC should revoke the regulations which codify this.
Any licensing decision approving high-density spent fuel
storage should have an EIS.
Comments opposing the petitions centered on the following:
Petitioners failed to show that regulatory relief is
needed to address ``new and significant'' information concerning the
potential for spent fuel zirconium fires in connection with high-
density SFP storage. None of the documents that the Petitioners cited
or referenced satisfy the NRC's standard for new and significant
information.
Petitioners failed to show that the Commission should
rescind its Waste Confidence decision codified at 10 CFR 51.23, or
change its determination that the environmental impacts of high-density
spent fuel storage are insignificant.
The Commission has recently affirmed its longstanding view
that NEPA demands no terrorism inquiry,
[[Page 46206]]
and that the NRC therefore need not consider the environmental
consequences of hypothetical terrorist attacks on NRC-licensed
facilities.
The Commission's rejection of the Ninth Circuit Court's
view is consistent with the U.S. Supreme Court's position that NEPA
should not be read to force agencies to consider environmental impacts
for which they cannot reasonably be held responsible. Moreover, the NRC
has, in fact, examined terrorism under NEPA and found the impacts
similar to the impacts of already-analyzed, severe reactor accidents.
The NRC reviewed and considered the comments in its decision to
deny both petitions, as discussed in the following sections:
IV. NEPA and NUREG-1437
The NRC's environmental protection regulations in 10 CFR Part 51
identify renewal of a nuclear power plant operating license as a major
federal action significantly affecting the quality of the human
environment. As such, an EIS is required for a plant license renewal
review in accordance with the NEPA. The Petitioners challenge NUREG-
1437, which generically assesses the significance of various
environmental impacts associated with the renewal of nuclear power
plant licenses. NUREG-1437 summarizes the findings of a systematic
inquiry into the potential environmental consequences of operating
individual nuclear power plants for an additional 20 years. The
findings of NUREG-1437 are codified in Table B-1 of appendix B to
subpart A of 10 CFR part 51.
The NUREG-1437 analysis identifies the attributes of the nuclear
power plants, such as major features and plant systems, and the ways in
which the plants can affect the environment. The analysis also
identifies the possible refurbishment activities and modifications to
maintenance and operating procedures that might be undertaken given the
requirements of the safety review as provided for in the NRC's nuclear
power plant license renewal regulations at 10 CFR part 54.
NUREG-1437 assigns one of three impact levels (small, moderate, or
large) to a given environmental resource (e.g., air, water, or soil). A
small impact means that the environmental effects are not detectable,
or are so minor that they will neither destabilize, nor noticeably
alter, any important attribute of the resource. A moderate impact means
that the environmental effects are sufficient to alter noticeably, but
not to destabilize, important attributes of the resource. A large
impact means that the environmental effects are clearly noticeable, and
are sufficient to destabilize important attributes of the resource.
In addition to determining the significance of environmental
impacts associated with license renewal, the NRC determined whether the
analysis in NUREG-1437 for a given resource can be applied to all
plants. Under the NUREG-1437 analysis, impacts will be considered
Category 1 or Category 2. A Category 1 determination means that the
environmental impacts associated with that resource are generic (i.e.,
the same) for all plants. A Category 2 determination means that the
environmental impacts associated with that resource cannot be
generically assessed, and must be assessed on a plant-specific basis.
The NRC regulations at 10 CFR part 51, subpart A, appendix B, Table
B-1 and NUREG-1437 set forth three criteria for an issue to be
classified as Category 1. The first criterion is that the environmental
impacts associated with that resource have been determined to apply to
all plants. The second criterion is that a single significance level
(i.e., small, moderate, or large) has been assigned to the impacts.\1\
The third criterion is that the mitigation of any adverse impacts
associated with the resource has been considered in NUREG-1437 and
further, it has been determined that additional plant-specific
mitigation measures are not likely to be sufficiently beneficial to
warrant implementation. For Category 1 issues, the generic analysis may
be adopted in each plant-specific license renewal review.
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\1\ A note to Table B-1 states that significance levels have not
been assigned ``for collective off site radiological impacts from
the fuel cycle and from high level waste and spent fuel disposal.''
10 CFR part 51, subpart A, app. B, Table B-1, n. 2.
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A Category 2 classification means that the NUREG-1437 analysis does
not meet the criteria of Category 1. Thus, on that particular
environmental issue, additional plant-specific review is required and
must be analyzed by the license renewal applicant in its ER.
For each license renewal application, the NRC will prepare a draft
supplemental EIS (SEIS) to analyze those plant-specific (Category 2)
issues. Neither the SEIS nor the ER is required to cover Category 1
issues. However, both are required to consider any new and significant
information for Category 1 or unidentified issues. The draft SEIS is
made available for public comment. After considering public comments,
the NRC will prepare and issue the final SEIS in accordance with 10 CFR
51.91 and 51.93. The final SEIS and NUREG-1437, together, serve as the
requisite NEPA analysis for any given license renewal application.
The NUREG-1437 analysis, as shown in Table B-1 of appendix B to
subpart A of 10 CFR part 51, found that the environmental impact of the
storage of spent nuclear fuel, including high-density storage, in SFPs,
during any plant refurbishment or plant operation through the license
renewal term, are of a small significance level and meet all Category 1
criteria. It is this finding that the Petitioners challenge. After
reviewing the petitions and the public comments received, the NRC has
determined that its findings in NUREG-1437 and in Table B-1 remain
valid, both for SFP accidents and for potential terrorist attacks that
could result in an SFP zirconium fire.
V. Reasons for Denial--General
A. Spent Fuel Pools
Spent nuclear fuel offloaded from a reactor is stored in a SFP. The
SFPs at all nuclear plants in the United States are massive, extremely-
robust structures designed to safely contain the spent fuel discharged
from a nuclear reactor under a variety of normal, off-normal, and
hypothetical accident conditions (e.g., loss of electrical power,
floods, earthquakes, or tornadoes). SFPs are made of thick, reinforced,
concrete walls and floors lined with welded, stainless-steel plates to
form a leak-tight barrier. Racks fitted in the SFPs store the fuel
assemblies in a controlled configuration (i.e., so that the fuel is
both sub-critical and in a coolable geometry). Redundant monitoring,
cooling, and makeup-water systems are provided. The spent fuel
assemblies are positioned in racks at the bottom of the pool, and are
typically covered by at least 25 feet of water. SFPs are essentially
passive systems.
The water in the SFPs provides radiation shielding and spent fuel
assembly cooling. It also captures radionuclides in case of fuel rod
leaks. The water in the pool is circulated through heat exchangers for
cooling. Filters capture any radionuclides and other contaminants that
get into the water. Makeup water can also be added to the pool to
replace water loss.
SFPs are located at reactor sites, typically within the fuel-
handling (pressurized-water reactor) or reactor building (boiling-water
reactor). From a structural point of view, nuclear power plants are
designed to protect against external events such as tornadoes,
hurricanes, fires, and floods. These structural features, complemented
by the deployment of effective and visible
[[Page 46207]]
physical security protection measures, are also deterrents to terrorist
activities. Additionally, the emergency procedures and SAMA guidelines
developed for reactor accidents provide a means for mitigating the
potential consequences of terrorist attacks.
B. Physical Security
The Petitioners raise the possibility of a successful terrorist
attack as increasing the probability of an SFP zirconium fire. As the
NAS Report found, the probability of terrorist attacks on SFPs cannot
be reliably assessed, quantitatively or comparatively. The NRC has
determined, however, that security and mitigation measures the NRC has
imposed upon its licensees since September 11, 2001, and national anti-
terrorist measures to prevent, for example, aircraft hijackings,
coupled with the robust nature of SFPs, make the probability of a
successful terrorist attack, though numerically indeterminable, very
low.
The NRC's regulations and security orders require licensees to
develop security and training plans for NRC review and approval,
implement procedures for these plans, and to periodically demonstrate
proficiency through tests and exercises.\2\ In addition, reactor
physical security systems use a defense-in-depth concept, involving the
following:
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\2\ For additional related information, please see the NRC fact
sheet ``NRC Review of Paper on Reducing Hazards From Stored Spent
Nuclear Fuel,'' which is available on the NRC's public Web site at:
http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/reducing-hazards-spent-fuel.html.
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Vehicle (external) barriers.
Fences.
Intrusion detection, alarm, and assessment systems.
Internal barriers.
Armed responders.
Redundant alarm stations with command, control, and
communications systems.
Local law enforcement authority's response to a site and
augmentation of the on-site armed response force.
Security and emergency-preparedness procedure development
and planning efforts with local officials.
Security personnel training and qualification.
The NRC's regulatory approach for maintaining the safety and
security of power reactors, and thus SFPs, is based upon robust designs
that are coupled with a strategic triad of preventive/protective
systems, mitigative systems, and emergency-preparedness and response.
Furthermore, each licensee's security functions are integrated and
coordinated with reactor operations and emergency response functions.
Licensees develop protective strategies in order to meet the NRC
design-basis threat (DBT).\3\ In addition, other Federal agencies such
as the Federal Aviation Administration, the Federal Bureau of
Investigation, and the Department of Homeland Security have taken
aggressive steps to prevent terrorist attacks in the United States.
Taken as a whole, these systems, personnel, and procedures provide
reasonable assurance that public health and safety, the environment,
and the common defense and security will be adequately protected.
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\3\ The DBT represents the largest threat against which a
private sector facility can be reasonably expected to defend with
high assurance. The NRC's DBT rule was published in the Federal
Register on March 19, 2007 (72 FR 12705).
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C. Very Low Risk
Risk is defined as the probability of the occurrence of a given
event multiplied by the consequences of that event.\4\ Studies
conducted over the last three decades have consistently shown that the
probability of an accident causing a zirconium fire in an SFP to be
lower than that for severe reactor accidents. The risk of beyond
design-basis accidents (DBAs) in SFPs was first examined as part of the
landmark Reactor Safety Study: An Assessment of Accident Risks in U.S.
Commercial Nuclear Power Plants (WASH-1400, NUREG-75/014, 1975), and
was found to be several orders of magnitude below those involving the
reactor core. The risk of an SFP accident was re-examined in the 1980's
as Generic Issue 82, Beyond Design Basis Accidents in Spent Fuel Pools,
in light of increased use of high-density storage racks and laboratory
studies that indicated the possibility of zirconium fire propagation
between assemblies in an air-cooled environment. The risk assessment
and cost-benefit analyses developed through this effort, NUREG-1353,
Regulatory Analysis for the Resolution of Generic Issue 82, Beyond
Design Basis Accidents in Spent Fuel Pools, Section 6.2, April 1989,
concluded that the risk of a severe accident in the SFP was low and
``appear[s] to meet'' the objectives of the Commission's ``Safety Goals
for the Operations of Nuclear Power Plants; Policy Statement,'' (August
4, 1986; 51 FR 28044), as amended (August 21, 1986; 51 FR 30028), and
that no new regulatory requirements were warranted.\5\
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\4\ The American Society of Mechanical Engineers (ASME)
``Standard for Probabilistic Risk Assessment for Nuclear Power Plant
Applications,'' ASME RA-S-2002, defines risk as the probability and
consequences of an event, as expressed by the risk ``triplet'' that
is the answer to the following three questions: (1) What can go
wrong? (2) How likely is it? and (3) What are the consequences if it
occurs?
\5\ The Commission's Safety Goals identified two quantitative
objectives concerning mortality risks: (1) The risk to an average
individual in the vicinity of a nuclear power plant of prompt
fatalities that might result from reactor accidents should not
exceed one-tenth of one percent (0.1 percent) of the sum of prompt
fatality risks resulting from other accidents in which members of
the U.S. population are generally exposed; and (2) The risk to the
population in the area near a nuclear power plant of cancer
fatalities that might result from nuclear power plant operation
should not exceed one-tenth of one percent (0.1 percent) of the sum
of cancer fatality risks resulting from all other causes.
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SFP accident risk was re-assessed in the late 1990s to support a
risk-informed rulemaking for permanently shutdown, or decommissioned,
nuclear power plants. The study, NUREG-1738, Technical Study of Spent
Fuel Pool Accident Risk at Decommissioning Nuclear Power Plants,
January 2001, conservatively assumed that if the water level in the SFP
dropped below the top of the spent fuel, an SFP zirconium fire
involving all of the spent fuel would occur, and thereby bounded those
conditions associated with air cooling of the fuel (including partial-
draindown scenarios) and fire propagation. Even when all events leading
to the spent fuel assemblies becoming partially or completely uncovered
were assumed to result in an SFP zirconium fire, the study found the
risk of an SFP fire to be low and well within the Commission's Safety
Goals.
Furthermore, significant additional analyses have been performed
since September 11, 2001, that support the view that the risk of a
successful terrorist attack (i.e., one that results in an SFP zirconium
fire) is very low. These analyses were conducted by the Sandia National
Laboratories and are collectively referred to herein as the ``Sandia
studies.'' \6\ The Sandia studies
[[Page 46208]]
are sensitive security related information and are not available to the
public. The Sandia studies considered spent fuel loading patterns and
other aspects of a pressurized-water reactor SFP and a boiling-water
reactor SFP, including the role that the circulation of air plays in
the cooling of spent fuel. The Sandia studies indicated that there may
be a significant amount of time between the initiating event (i.e., the
event that causes the SFP water level to drop) and the spent fuel
assemblies becoming partially or completely uncovered. In addition, the
Sandia studies indicated that for those hypothetical conditions where
air cooling may not be effective in preventing a zirconium fire (i.e.,
the partial drain down scenario cited by the Petitioners), there is a
significant amount of time between the spent fuel becoming uncovered
and the possible onset of such a zirconium fire, thereby providing a
substantial opportunity for both operator and system event mitigation.
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\6\ Sandia National Laboratories, ``Mitigation of Spent Fuel
Pool Loss-of-Coolant Inventory Accidents and Extension of Reference
Plant Analyses to Other Spent Fuel Pools,'' Sandia Letter Report,
Revision 2 (November 2006) incorporates and summarizes the Sandia
Studies. This document is designated ``Official Use Only--Security
Related Information.'' A version of the Sandia Studies, with
substantial redactions, was made public as a response to a Freedom
of Information Act request. It is available on the NRC's Agencywide
Document Access and Management System (ADAMS). The redacted version
can be found under ADAMS Accession No. ML062290362. For access to
ADAMS, contact the NRC Public Document Room Reference staff at 1-
800-397-4209, 301-415-4737, or by e-mail to [email protected].
For additional related information, please see the NRC fact sheet
``NRC Review of Paper on Reducing Hazards From Stored Spent Nuclear
Fuel,'' which is available on the NRC's public Web site at: http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/reducing-hazards-spent-fuel.html.
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The Sandia studies, which more fully account for relevant heat
transfer and fluid flow mechanisms, also indicated that air-cooling of
spent fuel would be sufficient to prevent SFP zirconium fires at a
point much earlier following fuel offload from the reactor than
previously considered (e.g., in NUREG-1738). Thus, the fuel is more
easily cooled, and the likelihood of an SFP fire is therefore reduced.
Additional mitigation strategies implemented subsequent to
September 11, 2001, enhance spent fuel coolability and the potential to
recover SFP water level and cooling prior to a potential SFP zirconium
fire. The Sandia studies also confirmed the effectiveness of additional
mitigation strategies to maintain spent fuel cooling in the event the
pool is drained and its initial water inventory is reduced or lost
entirely. Based on this more recent information, and the implementation
of additional strategies following September 11, 2001, the probability,
and accordingly, the risk, of a SFP zirconium fire initiation is
expected to be less than reported in NUREG-1738 and previous studies.
Given the physical robustness of SFPs, the physical security
measures, and SFP mitigation measures, and based upon NRC site
evaluations of every SFP in the United States, the NRC has determined
that the risk of an SFP zirconium fire, whether caused by an accident
or a terrorist attack, is very low. As such, the NRC's generic findings
in NUREG-1437, as further reflected in Table B-1 of appendix B to
subpart A of 10 CFR part 51, remain valid.
VI. Reasons for Denial--NRC Responses to Petitioners' Assertions
A. New and Significant Information
The Petitioners asserted that new and significant information shows
that the NRC incorrectly characterized the environmental impacts of
spent fuel storage as ``insignificant.'' The information relied upon by
the Petitioners, however, is neither ``new'' nor ``significant,''
within the NRC's definition of those terms. The NRC defines these terms
in its Supplement 1 to NRC Regulatory Guide 4.2, Preparation of
Supplemental Environmental Reports for Applications to Renew Nuclear
Power Plant Operating Licenses, Chapter 5 (September 2000) (RG 4.2S1).
``New and significant'' information, which would require supplementing
NUREG-1437, is defined as follows:
(1) Information that identifies a significant environmental
issue that was not considered in NUREG-1437 and, consequently, not
codified in Appendix B to Subpart A of 10 CFR Part 51, or
(2) Information that was not considered in the analyses
summarized in NUREG-1437 and that leads to an impact finding
different from that codified in 10 CFR Part 51.
The Petitioners' ``new and significant'' information does not meet
the RG 4.2S1 criteria. NUREG-1437 (Sections 6.4.6.1. to 6.4.6.3.), and
the analyses cited therein, including the NRC's ``Waste Confidence
Rule'' (September 18, 1990; 55 FR 38474, 38480-81), extensively
considered the risk of SFP accidents. Moreover, to the extent any
information submitted by the Petitioners was not considered in NUREG-
1437, none of the information is ``significant,'' because, as explained
further in this document, it would not lead to ``an impact finding
different from that codified in 10 CFR Part 51,'' or as set forth in
NUREG-1437.
B. Spent Fuel Assemblies Will Burn If Uncovered
The Petitioners asserted that new and significant information,
consisting primarily of the Thompson Report, NUREG-1738, and a
government-sponsored study, the NAS Report, show that spent fuel will
burn if the water level in an SFP drops to the point where the tops of
the fuel assemblies are uncovered. Specifically, the Petitioners
asserted that the NRC fails to recognize the danger of a partial loss
of water in an SFP, which in the Petitioners' view, is more likely to
cause an SFP zirconium fire than a complete loss of water, because the
remaining water will block the circulating air that would otherwise act
to cool the spent fuel assemblies.
The NRC does not agree with the Petitioners' assertions. The NRC
has determined that a zirconium cladding fire does not occur when only
the tops of the fuel assemblies are uncovered. In reality, a zirconium
fire cannot occur unless fuel uncovering is more substantial. Even
then, the occurrence of a zirconium fire requires a number of
conditions which are extremely unlikely to occur together. The Sandia
studies provide a more realistic assessment of the coolability of spent
fuel under a range of conditions and a better understanding of the
actual safety margins than was indicated in NUREG-1738. The Sandia
studies have consistently and conclusively shown that the safety
margins are much larger than indicated by previous studies such as
NUREG-1738.
1. Heat Transfer Mechanisms
Past NRC studies of spent fuel heatup and zirconium fire initiation
conservatively did not consider certain natural heat-transfer
mechanisms which would serve to limit heatup of the spent fuel
assemblies and prevent a zirconium fire. In particular, these studies,
including NUREG-1738, did not consider heat transfer from higher-decay-
power assemblies to older, lower-decay-power fuel assemblies in the
SFP. This heat transfer would substantially increase the effectiveness
of air cooling in the event the SFP is drained, far beyond the
effectiveness of air cooling cited in past studies. Both the Sandia
studies and the NAS Report confirm the NRC conclusion that such heat
transfer mechanisms allow rapid heat transfer away from the higher-
powered assemblies. The NAS Report also noted that such heat transfer
could air-cool the assemblies to prevent a zirconium fire within a
relatively short time after the discharge of assemblies from the
reactor to the SFP.\7\ Thus, air cooling is an effective, passive
mechanism for cooling spent fuel assemblies in the pool.
---------------------------------------------------------------------------
\7\ NAS Report at 53.
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2. Partial Drain-Down
Air cooling is less effective under the special, limited condition
where the water level in the SFP drops to a point where water and steam
cooling is not sufficient to prevent the fuel from overheating and
initiating a zirconium fire, but the water level is high enough to
block the full natural circulation of air flow through the assemblies.
This condition has been commonly referred to as a partial draindown,
and is cited in the Thompson Report. Under those
[[Page 46209]]
conditions, however, it is important to realistically model the heat
transfer between high- and low-powered fuel assemblies. The heat
transfer from hot fuel assemblies to cooler assemblies will delay the
heat-up of assemblies, and allow plant operators time to take
additional measures to restore effective cooling to the assemblies.
Further, for very low-powered assemblies, the downward flow of air into
the assemblies can also serve to cool the assembly even though the
full-circulation flow path is blocked. Also, as discussed further in
this document, all nuclear plant SFPs have been assessed to identify
additional, existing cooling capability and to provide new supplemental
cooling capability which could be used during such rare events. This
supplemental cooling capability specifically addresses the cooling
needs during partial draindown events, and would reduce the probability
of a zirconium fire even during those extreme events.
3. License Amendments
In January 2006, the nuclear industry proposed a combination of
internal and external strategies to enhance the spent fuel heat removal
capability systems at every operating nuclear power plant. The internal
strategy implements a diverse SFP makeup system that can supply the
required amount of makeup water and SFP spray to remove decay heat. The
external strategy involves using an independently-powered, portable,
SFP coolant makeup and spray capability system that enhances spray and
rapid coolant makeup to mitigate a wide range of possible scenarios
that could reduce SFP water levels. In addition, in cases where SFP
water levels can not be maintained, leakage control strategies would be
considered along with guidance to maximize spray flows to the SFP. Time
lines have been developed that include both dispersed and non-dispersed
spent fuel storage. The NRC has approved license amendments and issued
safety evaluations to incorporate these strategies into the plant
licensing bases of all operating nuclear power plants in the United
States.
C. Fuel Will Burn Regardless of Its Age
The NRC disagrees with the Petitioners' assertion that fuel will
burn regardless of age. Older fuel (fuel which has been discharged from
the reactor for a longer time) is more easily cooled and is less likely
to ignite because of its lower decay power. A study relied upon by the
Petitioners, NUREG-1738, did conservatively assume that spent fuel
stored in an SFP, regardless of age, may be potentially vulnerable to a
partial drain down event, and that the possibility of a zirconium fire
could not be ruled out on a generic basis. This conclusion, however,
was in no sense a statement of certainty and was made in order to reach
a conclusion on a generic basis, without relying on any plant-specific
analyses.
Furthermore, the SFP zirconium fire frequency in NUREG-1738 was
predicated on a bounding, conservative assumption that an SFP fire
involving all of the spent fuel would occur if the water level in the
SFP dropped below the top of the spent fuel. The NUREG-1738 analysis
did not attempt to specifically address a number of issues and actions
that would substantially reduce the likelihood of a zirconium fire,
potentially rendering the frequency estimate to be remote and
speculative. For example, NUREG-1738 did not account for the additional
time available following the spent fuel being partially or completely
uncovered, but prior to the onset of a zirconium fire, that would allow
for plant operator actions, makeup of SFP water levels, and other
mitigation measures. In addition, NUREG-1738 did not consider the
impact of plant and procedure changes implemented as a result of the
events of the September 11, 2001, terrorist attacks. NUREG-1738 did
clarify that the likelihood of a zirconium fire under such conditions
could be reduced by accident management measures, but it was not the
purpose of NUREG-1738 to evaluate such accident management measures.
D. SFP Zirconium Fire Will Propagate
Although it is possible that once a spent fuel assembly ignites,
the zirconium fire can propagate to other assemblies in the SFP, the
NRC has determined (as explained previously) that the risk of an SFP
zirconium fire initiation is very low.
E. SFP Zirconium Fire May Be Catastrophic
1. Not New and Significant Information; Very Low Probability
The Massachusetts AG states that ``while such a catastrophic
accident is unlikely, its probability falls within the range that NRC
considers reasonably foreseeable.'' Thus, the Petitioners asserted that
an SFP zirconium fire qualifies as a DBA and, that the impacts of an
SFP fire must be discussed in the ER submitted by the licensee and the
NRC's EIS, as well as designed against under NRC safety regulations.
The facts that a SFP contains a potentially large inventory of
radionuclides and that a release of that material could have adverse
effects are not new. These facts are well known, and were considered in
the risk evaluation of spent fuel storage contained in NUREG-1738. Even
with the numerous conservatisms in the NUREG-1738 study, as described
previously, the NRC was able to conclude that the risk from spent fuel
storage is low, and is substantially lower than reactor risk.
A study relied upon by the Petitioners, the Thompson Report,
claimed that the probability (frequency) of an SFP zirconium fire would
be 2E-5 per year \8\ for events excluding acts of malice (e.g.,
terrorism) and 1E-4 per year \9\ for acts of malice. With respect to
random events (i.e., excluding acts of malice), the NRC concludes that
the Thompson Report estimate is overly conservative. A more complete
and mechanistic assessment of the event, as described in section
VI.E.2. of this Notice, and associated mitigation measures, leads to
considerably lower values. With respect to events initiated by a
terrorist attack, the NRC concludes that such probability (frequency)
estimates are entirely speculative. The NRC also concludes that the
additional mitigation measures for SFP events implemented since
September 11, 2001, together with the more realistic assessment of
spent fuel cooling, indicates that the likelihood of a zirconium fire,
though numerically indeterminable, is very low.
---------------------------------------------------------------------------
\8\ Two occurrences in 100,000 reactor years.
\9\ One occurrence in 10,000 reactor years.
---------------------------------------------------------------------------
The 2E-5 per year estimate for events excluding acts of malice is
based on an unsubstantiated assumption that 50 percent of all severe
reactor accidents that result in an early release of substantial
amounts of radioactive material will also lead to a consequential SFP
zirconium fire. The Thompson Report does not identify the necessary
sequence of events by which such scenarios might lead to SFP zirconium
fires, or discuss the probability of their occurrence. The NRC analysis
in the Shearon Harris ASLBP proceeding (described in section VI.E.2. of
this Notice) showed that a more complete and mechanistic assessment of
the event and associated mitigation measures leads to considerably
lower values. This assessment includes the following:
Frequency and characteristics of the releases from the
containment for each release location;
Transport of gases and fission products within the reactor
building;
[[Page 46210]]
Resulting thermal and radiation environments in the
reactor building, with emphasis on areas in which SFP cooling and
makeup equipment is located, and areas in which operator access may be
needed to implement response actions;
Availability/survivability of SFP cooling and makeup
equipment in the sequences of concern; and
Ability and likelihood of successful operator actions to
maintain or restore pool cooling or makeup (including consideration of
security enhancements and other mitigation measures implemented in
response to the terrorist attacks of September 11, 2001).
2. Shearon Harris Atomic Safety and Licensing Board Panel (ASLBP)
Proceeding
In the proceeding regarding the expansion of the SFP at the Shearon
Harris nuclear power plant, located near Raleigh, North Carolina, the
Shearon Harris intervenor described a scenario similar to that raised
by the Petitioners, namely, that a severe accident at the adjacent
reactor would result in a SFP zirconium fire.\10\ The Shearon Harris
proceeding considered the probability of a sequence of the following
seven events:
---------------------------------------------------------------------------
\10\ Carolina Power Light Co., LBP-01-9, 53 NRC 239, 244-245
(2001).
---------------------------------------------------------------------------
a. A degraded core accident.
b. Containment failure or bypass.
c. Loss of SFP cooling.
d. Extreme radiation levels precluding personnel access.
e. Inability to restart cooling or makeup systems due to extreme
radiation doses.
f. Loss of most or all pool water through evaporation.
g. Initiation of a zirconium fire in the SFP.
Based on a detailed probabilistic risk assessment, the licensee
calculated the probability of a severe reactor accident that causes an
SFP zirconium fire to be 2.78E-8 per year. The NRC staff calculated the
probability to be 2.0E-7 per year. The intervenor calculated the
probability to be 1.6E-5 per year. The ASLBP concluded that the
probability of the postulated sequence of events resulting in an SFP
zirconium fire was ``conservatively in the range described by the
Staff: 2.0E-7 per year (two occurrences in 10 million reactor years) or
less.'' \11\ Accordingly, the ASLBP found that the occurrence of a
severe reactor accident causing an SFP zirconium fire ``falls within
the category of remote and speculative matters.'' \12\ The Commission
affirmed the ASLBP's decision, and the United States Court of Appeals,
District of Columbia Circuit, upheld the Commission decision.\13\
---------------------------------------------------------------------------
\11\ Id., 53 NRC at 267.
\12\ Id., 53 NRC at 268.
\13\ Carolina Power Light Co., Commission Law Issuance (CLI)-01-
11, 53 NRC 370 (2001), pet. for review denied, sub nom, Orange
County, NC v. NRC, 47 Fed. Appx. 1, 2002 WL 31098379 (D.C. Cir.
2002).
---------------------------------------------------------------------------
In the Shearon Harris proceeding, the intervenor assumed that,
given an early containment failure or bypass, a spent fuel zirconium
fire would occur (i.e., a conditional probability of 1.0). In order for
a reactor accident to lead to a SFP zirconium fire a number of
additional conditions must occur. The reactor accident and containment
failure must somehow lead to a loss of SFP cooling and must lead to a
condition where extreme radiation levels preclude personnel access to
take corrective action. There must be then an inability to restart
cooling or makeup systems. There must be a loss of significant pool
water inventory through evaporation (which can take substantial time).
Finally, the event must also lead to a zirconium fire. In contrast to
the intervenor's estimate, the licensee and the NRC staff estimated a
conditional probability of about one percent that a severe reactor
accident with containment failure would lead to a SFP accident. The NRC
staff expects that the conditional probability of a SFP zirconium fire,
given a severe reactor accident, would be similar to that established
in the Shearon Harris proceeding. As such, the probability of a SFP
zirconium fire due to a severe reactor accident and subsequent
containment failure would be well below the Petitioners' 2E-5 per year
estimate.
The 1E-4 per year estimate in the Thompson Report for events
involving acts of malice assumes that there would be one attack on the
population of U.S. nuclear power plants per century, and that this
attack will be 100 percent successful in producing a SFP zirconium fire
(thus, fire frequency = 0.01 attack/year x 1.0 fire/attack x 1/104
total reactors = 1E-4/year). The security-related measures and other
mitigation measures implemented since September 11, 2001, however, have
significantly reduced the likelihood of a successful terrorist attack
on a nuclear power plant and its associated SFP. Such measures include
actions that would improve the likelihood of the following:
a. Identifying/thwarting the attack before it is initiated.
b. Mitigating the attack before it results in damage to the plant.
c. Mitigating the impact of the plant damage such that an SFP
zirconium fire is avoided.
Given the implementation of additional security enhancements and
mitigation strategies, as well as further consideration of the factors
identified above, the NRC staff concludes that the frequency of SFP
zirconium fires due to acts of malice is substantially lower than
assumed by the Petitioners.
3. SFP Zirconium Fire Does Not Qualify As a DBA
Regarding the Petitioners' assertion that a SFP zirconium fire
qualifies as a design-basis accident (DBA), the NRC staff has concluded
that a realistic probability estimate would be very low, such that
these events need not be considered as DBAs or discussed in ERs and
EISs. Moreover, the set of accidents that must be addressed as part of
the design basis has historically evolved from deterministic rather
than probabilistic considerations. These considerations, which include
defense-in-depth, redundancy, and diversity, are characterized by the
use of the single-failure criterion.\14\ The single-failure criterion,
as a key design and analysis tool, has the direct objective of
promoting reliability through the enforced provision of redundancy in
those systems which must perform a safety-related function. The single
failure criterion is codified in Appendix A and Appendix K to 10 CFR
Part 50 and other portions of the regulations. The SFP and related
systems have been designed and approved in accordance with this
deterministic approach.
---------------------------------------------------------------------------
\14\ ``A single failure means an occurrence which results in the
loss of capability of a component to perform its intended safety
functions * * * Fluid and electric systems are considered to be
designed against an assumed single failure if neither (1) a single
failure of any active component * * * nor (2) a single failure of a
passive component * * * results in a loss of the capability of the
system to perform its safety functions.'' 10 CFR Part 50, App. A.
---------------------------------------------------------------------------
F. Intentional Attack on a SFP is ``Reasonably Foreseeable.''
The Petitioners asserted that an intentional attack targeting a
plant's SFP is ``reasonably foreseeable.'' Specifically, the
Petitioners raised both the NAS study and the decision by the United
States Court of Appeals for the Ninth Circuit, San Luis Obispo Mothers
for Peace v. NRC, 449 F.3d 1016 (9th Cir. 2006), cert. denied 127 S.
Ct. 1124 (2007), to support the assertion that the NRC's NEPA analysis
of a license renewal action for a given facility must include analysis
of the environmental impacts associated with a terrorist attack on that
facility. The NRC has
[[Page 46211]]
considered both the NAS Report and the Ninth Circuit decision, and
remains of the view that an analysis of the environmental impacts of a
hypothetical terrorist attack on an NRC-licensed facility is not
required under NEPA.\15\ But, if an analysis of a hypothetical
terrorist attack were required under NEPA, the NRC has determined that
the environmental impacts of such a terrorist attack would not be
significant, because the probability of a successful terrorist attack
(i.e., one that causes an SFP zirconium fire, which results in the
release of a large amount of radioactive material into the environment)
is very low and therefore, within the category of remote and
speculative matters.
---------------------------------------------------------------------------
\15\ In the wake of the Ninth Circuit's Mothers for Peace
decision, the Commission decided against applying that holding to
all licensing proceedings nationwide. See, e.g., Amergen Energy Co.
LLC (Oyster Creek Nuclear Generating Station), CLI-07-8, 65 NRC 124,
128-29 (2007), pet. for judicial review pending, No. 07-2271 (3d
Cir.). The Commission will, of course, adhere to the Ninth Circuit
decision when considering licensing actions for facilities subject
to the jurisdiction of that Circuit. See id. Thus, on remand in the
Mothers for Peace case itself, the Commission is currently
adjudicating intervenors' claim that the NRC Staff has not
adequately assessed the environmental consequences of a terrorist
attack on the Diablo Canyon Power Plant's proposed facility for
storing spent nuclear fuel in dry casks. See, Pacific Gas & Elec.
Co., CLI-07-11, 65 NRC 148 (2007). The Commission's ultimate
decision in that case will rest on the record developed in the
adjudication.
---------------------------------------------------------------------------
1. NAS Report
The Petitioners rely, in part, upon the NAS Report, the public
version of which was published in 2006 and is available from NAS.\16\
In response to a direction in the Conference Committee's Report
accompanying the NRC's FY 2004 appropriation,\17\ the NRC contracted
with NAS for a study on the safety and security of commercial spent
nuclear fuel. The NAS made a number of findings and recommendations,
including:
---------------------------------------------------------------------------
\16\ The NRC response to the NAS Report is available at ADAMS
Accession No. ML0502804280.
\17\ Conference Committee's Report (H. Rept. 108-357)
accompanying the Energy and Water Development Act, 2004 (Pub. L.
108-137, December 3, 2003).
---------------------------------------------------------------------------
SFPs are necessary at all operating nuclear power plants
to store recently discharged fuel;
Successful terrorist attacks on SFPs, though difficult,
are possible;
The probability of terrorist attacks on spent fuel storage
cannot be assessed quantitatively or comparatively;
If a successful terrorist attack leads to a propagating
zirconium cladding fire, it could result in the release of large
amounts of radioactive material; and
Dry cask storage has inherent security advantages over
spent fuel storage, but it can only be used to store older spent fuel.
The NAS Report found, and the NRC agrees, that pool storage is
required at all operating commercial nuclear power plants to cool newly
discharged spent fuel. Freshly discharged spent fuel generates too much
decay heat to be placed in a dry storage cask.
The NRC agrees with the NAS finding that the probability of
terrorist attacks on spent fuel storage cannot be assessed
quantitatively or comparatively. However, the NRC concludes that the
additional mitigation measures for SFP events implemented since
September 11, 2001, together with a more realistic assessment of spent
fuel cooling, as shown by the Sandia studies, indicates that the
likelihood of a zirconium fire, though numerically indeterminate, is
very low.
Furthermore, the NAS Report states that ``[i]t is important to
recognize, however, that an attack that damages a power plant or its
spent fuel storage facilities would not necessarily result in the
release of any radioactivity to the environment. There are potential
steps that can be taken to lower the potential consequences of such
attacks.'' \18\ The NAS Report observed that a number of security
improvements at nuclear power plants have been instituted since
September 11, 2001, although the NAS did not evaluate the effectiveness
and adequacy of these improvements and has called for an independent
review of such measures. Nevertheless, the NAS Report states that ``the
facilities used to store spent fuel at nuclear power plants are very
robust. Thus, only attacks that involve the application of large energy
impulses or that allow terrorists to gain interior access have any
chance of releasing substantial quantities of radioactive material.''
\19\
---------------------------------------------------------------------------
\18\ NAS Report at 6 (emphasis in the original).
\19\ NAS Report at 30.
---------------------------------------------------------------------------
As discussed previously, following the terrorist attacks of
September 11, 2001, the NRC has required that nuclear power plant
licensees implement additional security measures and enhancements the
Commission believes have made the likelihood of a successful terrorist
attack on an SFP remote.
2. Ninth Circuit Decision
The Petitioners asserted that the NRC should follow the decision of
the United States Court of Appeals for the Ninth Circuit, San Luis
Obispo Mothers for Peace v. NRC, 449 F.3d 1016 (9th Cir. 2006), cert.
denied 127 S. Ct. 1124 (2007), by considering the environmental impacts
of intentional attacks on nuclear power plant fuel storage pools in all
licensing decisions. The Ninth Circuit held that the NRC could not,
under NEPA, categorically refuse to consider the consequences of a
terrorist attack against a spent fuel storage facility on the Diablo
Canyon reactor site.
The NRC's longstanding view is that NEPA does not require the NRC
to consider the environmental consequences of hypothetical terrorist
attacks on NRC-licensed facilities. NEPA requires that there be a
``reasonably close causal relationship'' between the federal agency
action and the environmental consequences.\20\ The NRC renewal of a
nuclear power plant license would not cause a terrorist attack; a
terrorist attack would be caused by the terrorists themselves. Thus,
the renewal of a nuclear power plant license would not be the
``proximate cause'' of a terrorist attack on the facility.
---------------------------------------------------------------------------
\20\ Department of Transportation v. Public Citizen, 541 U.S.
752, 767 (2004) citing Metropolitan Edison v. People Against Nuclear
Energy, 460 U.S. 766, 774 (1983).
---------------------------------------------------------------------------
If NEPA required the NRC to consider the impacts of a terrorist
attack, however, the NRC findings would remain unchanged. As previously
described, the NRC has required, and nuclear power plant licensees have
implemented, various security and mitigation measures that, along with
the robust nature of SFPs, make the probability of a successful
terrorist attack (i.e., one that causes an SFP zirconium fire, which
results in the release of a large amount of radioactive material into
the environment) very low. As such, a successful terrorist attack is
within the category of remote and speculative matters for NEPA
considerations; it is not ``reasonably foreseeable.'' Thus, on this
basis, the NRC finds that the environmental impacts of renewing a
nuclear power plant license, in regard to a terrorist attack on an SFP,
are not significant.
The NRC has determined that its findings related to the storage of
spent nuclear fuel in pools, as set forth in NUREG-1437 and in Table B-
1 of Appendix B to Subpart A of 10 CFR Part 51, remain valid. Thus, the
NRC has met and continues to meet its obligations under NEPA.
G. SFP Zirconium Fire Should Be Considered Within the Analysis of SAMAs
The Petitioners asserted that SFP fires should be considered within
the analysis of severe accident mitigation alternatives (SAMAs). While
a large radiological release is still possible, and
[[Page 46212]]
was assessed as part of Generic Issue 82, Beyond Design Basis Accidents
in Spent Fuel Pools, and later, in NUREG-1738, the NRC considers the
likelihood of such an event to be lower than that estimated in Generic
Issue 82 and NUREG-1738. Based on the Sandia studies, and on the
implementation of additional strategies implemented following September
11, 2001, the probability of a SFP zirconium fire is expected to be
less than that reported in NUREG-1738 and previous studies. Thus, the
very low probability of an SFP zirconium fire would result in an SFP
risk level less than that for a reactor accident.
For example, in NUREG-1738, the SFP fire frequencies were
conservatively estimated to be in the range of 5.8E-7 per year to 2.4E-
6 per year. NUREG-1738 conservatively assumed that if the water level
in the SFP dropped below the top of the spent fuel, an SFP zirconium
fire involving all of the spent fuel would occur, and thereby bounded
those conditions associated with air cooling of the fuel (including
partial-drain down scenarios) and zirconium fire propagation. It did
not mechanistically analyze the time between the spent fuel assemblies
becoming partially or completely uncovered and the onset of a SFP
zirconium fire, and the potential to recover SFP cooling and to restore
the SFP water level within this time. NUREG-1738 also did not consider
the possibility that air-cooling of the spent fuel alone could be
sufficient to prevent SFP zirconium fires.
Furthermore, the Sandia studies indicated that air cooling would be
much more effective in cooling the spent fuel assemblies. In those
cases where air cooling is not effective, the time before fuel heatup
and radiological release would be substantially delayed, thus providing
a substantial opportunity for successful event mitigation. The Sandia
studies, which more fully account for relevant heat transfer and fluid
flow mechanisms, also indicated that air-cooling of spent fuel would be
sufficient to prevent SFP zirconium fires much earlier following fuel
offload than previously considered (e.g., in NUREG-1738), thereby
further reducing the likelihood of an SFP zirconium fire. Additional
mitigation strategies implemented subsequent to September 11, 2001,
will serve to further enhance spent fuel coolability, and the potential
to recover SFP cooling or to restore the SFP water level prior to the
initiation of an SFP zirconium fire.
Given that the SFP risk level is less than that for a reactor
accident, a SAMA that addresses SFP accidents would not be expected to
have a significant impact on total risk for the site. Despite the low
level of risk from fuel stored in SFPs, additional SFP mitigative
measures have been implemented by licensees since September 11, 2001.
These mitigative measures further reduce the risk from SFP zirconium
fires, and make it even more unlikely that additional SFP safety
enhancements could substantially reduce risk or be cost-beneficial.
VII. Denial of Petitions
Based upon its review of the petitions, the NRC has determined that
the studies upon which the Petitioners rely do not constitute new and
significant information. The NRC has further determined that its
findings related to the storage of spent nuclear fuel in pools, as set
forth in NUREG-1437 and in Table B-1, of Appendix B to Subpart A of 10
CFR Part 51, remain valid. Thus, the NRC has met and continues to meet
its obligations under NEPA. For the reasons discussed previously, the
Commission denies PRM-51-10 and PRM-51-12.
Commissioner Gregory B. Jaczko's Dissenting View on the Commission's
Decision To Deny Two Petitions for Rulemaking Concerning the
Environmental Impacts of High-Density Storage of Spent Nuclear Fuel in
Spent Fuel Pools
I disagree with the decision to deny the petition for rulemaking as
included in this Federal Register notice. In general, I approve of the
decision not to initiate a new rulemaking to resolve the petitioners'
concerns, but because information in support of the petition will be
considered when the staff undertakes the rulemaking to update the
Generic Environmental Impact Statement for license renewal, I believe
that the decision should have been to partially grant the petition
rather than deny it.
The petitioners requested the agency review additional studies
regarding spent fuel pool storage they believe would change the
agency's current generic determination that the impacts of high-density
pool storage are ``small''. I believe that the agency could commit to
reviewing the information provided by the petitioners, along with any
other new information, when the agency updates the Generic
Environmental Impact Statement (GEIS) for License Renewal in the near
future. Regardless of whether or not the information will change the
GEIS' conclusions, at a minimum, the agency should be committing to
ensure that this information is part of the analysis performed by the
staff upon the next update of the GEIS. While we can not predict the
outcome of the significance level that will ultimately be assigned to
the spent fuel category in the GEIS, it seems an obvious commitment to
ensure that the ultimate designation will be appropriately based upon
all information available to the staff at the time. Thus, I believe
this decision should be explained as a partial granting of the
petition. It may not provide the petitioners with everything they want,
but it would more clearly state the obvious--that this information, and
any other new information, will be reviewed by the agency and
appropriately considered when the staff begins its update of the
license renewal GEIS.
This specific issue illustrates a larger concern about how the
agency handles petitions for rulemaking in general. I find it
unfortunate that the agency appears to limit its responses to petitions
based upon the vocabulary that has been established surrounding this
program. Currently, when the agency discusses these petitions, we
discuss them in the context of ``granting'' or ``denying'' the
rulemaking petitions. We then appear to be less inclined to ``grant''
unless we are committing to the precise actions requested in the
petition. But these petitions are, by their very definition, requests
for rulemakings; which means, even if we do ``grant'' a petition for
rulemaking, we can not guarantee a particular outcome for the final
rule. The final rulemaking is the result of staff's technical work
regarding the rule, public comments on the rule, and resolution of
those comments. Rulemaking petitions are opportunities for our
stakeholders to provide us with new ideas and approaches for how we
regulate. By limiting our responses, we limit our review of the
request, and thus, we risk missing many potential opportunities to
improve the way we regulate.
Additional Views of the Commission
The Commission does not share Commissioner Jaczko's dissenting
view. We appreciate his statement of concern about the petition for
rulemaking (PRM) process, but believe these matters are extraneous to
the Commission's analyses of the petitioners' technical bases for this
particular rulemaking request and, consequently, they had no bearing on
the majority view. Specifically, the Commission does not agree that the
petitions should be granted in part on the basis of the agency's plan
to update the Generic Environmental Impact Statement (GEIS) for License
Renewal and make attendant
[[Page 46213]]
rule changes in the future. The Commission's detailed statement of
reasons for denial of the petitions is the product of a careful review
of the petitioners' assertions and other associated public comments,
and is supported by the facts before us. In these circumstances, the
Commission does not believe the petitioners' request can fairly, or
reasonably, be ``granted'' in part based on a future undertaking which
itself had no genesis in the petitioners' requests.
The Commission's timely and decisive action in response to the two
petitions serves the interests of the Commission and other participants
in an effective, disciplined, and efficient rulemaking petition
process. In this instance, a decision now has particular value since it
directly addresses the petitioners' statements of significant concern
about certain, generic aspects of ongoing and future license renewal
reviews. While the analyses performed to respond to these petitions
will also undoubtedly inform NRC staff proposals regarding the next
update of the GEIS, the Commission does not yet have such proposals
before it. Any final Commission decisions on an updated GEIS would be
preceded by proposed changes, solicitation of public comment, and
evaluation of all pertinent information and public comments.
Furthermore, a partial ``granting'' of the petition could imply that
the Commission endorses the petitioners' requests and will give them
greater weight than other points of view during the GEIS rulemaking.
As to the other matter raised in Commissioner Jaczko's dissent--
that of agency review and disposition of petitions for rulemaking more
generally--while petitions for rulemaking are indeed opportunities for
stakeholders to suggest new considerations and approaches for
regulation, Commissioner Jaczko's general concerns about the agency's
process for handling rulemaking petitions go beyond the subject of the
Commission's action on these petitions. However, this subject matter is
being considered, as the Commission has instructed NRC staff [SRM dated
August 6, 2007] to conduct a review of the agency's PRM process. At
such time as staff may recommend, as an outgrowth of this review,
specific proposals for Commission action which would strengthen the
agency PRM process, the Commission will assess such recommendations and
act on them, as appropriate.
Dated at Rockville, Maryland, this 1st day of August 2008.
For the Nuclear Regulatory Commission.
Annette L. Vietti-Cook,
Secretary of the Commission.
[FR Doc. E8-18291 Filed 8-7-08; 8:45 am]
BILLING CODE 7590-01-P