[Federal Register Volume 83, Number 8 (Thursday, January 11, 2018)]
[Notices]
[Pages 1383-1388]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-00318]
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NUCLEAR REGULATORY COMMISSION
[Docket Nos. 50-361 and 50-362; NRC-2018-0003]
Southern California Edison Company, San Onofre Nuclear Generating
Station, Units 2 and 3
AGENCY: Nuclear Regulatory Commission.
ACTION: Exemption; issuance.
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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing an
exemption from certain power reactor financial protection requirements
in response to a September 16, 2015, request from the Southern
California Edison Company (the licensee). The exemption would permit
the San Onofre Nuclear Generating Station, Units 2 and 3 (SONGS), to
reduce the required level of primary financial protection from $450
million to $100 million, as well as to withdraw from participation in
the secondary layer of financial protection effective immediately.
ADDRESSES: Please refer to Docket ID NRC-2018-0003 when contacting the
NRC about the availability of information regarding this document. You
may obtain publicly-available information related to this document
using any of the following methods:
Federal Rulemaking website: Go to http://www.regulations.gov and search for Docket ID NRC-2018-0003. Address
questions about NRC dockets to Carol Gallagher; telephone: 301-415-
3463; email: [email protected]. For technical questions, contact
the individual 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 http://www.nrc.gov/reading-rm/adams.html. To begin the search, select ``ADAMS Public Documents'' and
then 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, 301-415-4737, or by email to [email protected]. The
ADAMS accession number for each document referenced (if it is available
in ADAMS) is provided the first time that it is mentioned in this
document.
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: Marlayna Vaaler, Office of Nuclear
Material Safety and Safeguards; U.S. Nuclear Regulatory Commission,
Washington, DC 20555-0001; telephone: 301-415-3178; email:
[email protected].
SUPPLEMENTARY INFORMATION:
I. Background
The San Onofre Nuclear Generating Station, Units 1, 2, and 3
(SONGS), operated by the Southern California Edison Company (SCE) is
located approximately 4 miles south of San
[[Page 1384]]
Clemente, California. The SONGS, Unit 1, Docket No. 50-206, was a
Westinghouse 456 megawatt electric (MWe) pressurized water reactor
which was granted Facility Operating License No. DPR-13 on January 1,
1968 (ADAMS Accession No. ML13309A138), and ceased operation on
November 30, 1992 (ADAMS Accession No. ML13319B040). The licensee
completed defueling on March 6, 1993 (ADAMS Accession No. ML13319B055),
and maintained the unit in SAFSTOR until June 1999, when it initiated
decommissioning (ADAMS Accession No. ML13319B111). On December 28, 1993
(ADAMS Accession No. ML13319B059), the NRC approved the Permanently
Defueled Technical Specifications for SONGS, Unit 1.
The SCE submitted the proposed Decommissioning Plan for SONGS, Unit
1, on November 3, 1994 (ADAMS Accession No. ML13319B073). As a result
of the 1996 revision to the regulations in section 50.82 of title 10 of
the Code of Federal Regulations (10 CFR), the NRC replaced the
requirement for a decommissioning plan with a requirement for a Post
Shutdown Decommissioning Activities Report (PSDAR). On August 28, 1996,
the SONGS, Unit 1, Decommissioning Plan became the SONGS 1 PSDAR (61 FR
67079; December 19, 1996). On December 15, 1998 (ADAMS Accession No.
ML13184A353), SCE submitted an update to the PSDAR to the NRC, as
required by 10 CFR 50.82(a)(7), in order to begin planning for the
dismantlement and decommissioning of SONGS, Unit 1. The SONGS, Unit 1,
received approval for an exemption from the financial protection
requirements under 10 CFR part 140 and 10 CFR 50.54(w), similar to what
is being requested for SONGS, Units 2 and 3, on May 4, 1994.
The SONGS, Units 2 and 3, Docket Nos. 50-361 and 50-362, are
Combustion Engineering 1127 MWe pressurized water reactors, which were
granted Facility Operating Licenses NPF-10 on February 16, 1982, and
NPF-15 on November 15, 1982, respectively. In June 2013, pursuant to 10
CFR 50.82(a)(1)(i), the licensee certified to the NRC that as of June
4, 2013, operations had ceased at SONGS, Units 2 and 3 (ADAMS Accession
No. ML131640201). The licensee subsequently certified, pursuant to 10
CFR 50.82(a)(1)(ii), that all fuel had been removed from the reactor
vessels of both units, and committed to maintaining the units in a
permanently defueled status (ADAMS Accession Nos. ML13204A304 and
ML13183A391 for Unit 2 and Unit 3, respectively). Therefore, pursuant
to 10 CFR 50.82(a)(2), SCE's 10 CFR part 50 licenses no longer
authorize operation of SONGS Units 2 and 3, or emplacement or retention
of fuel in the reactor vessels. The licensee is still authorized to
possess and store irradiated nuclear fuel. Irradiated fuel is currently
being stored onsite in spent fuel pools (SFPs) and in dry casks at an
Independent Spent Fuel Storage Installation (ISFSI).
The PSDAR for SONGS, Units 2 and 3, was submitted on September 23,
2014 (ADAMS Accession No. ML14272A121), and the associated public
meeting was held on October 27, 2014, in Carlsbad, California (ADAMS
Accession No. ML14352A063). The NRC confirmed its review of the SONGS,
Units 2 and 3, PSDAR and addressed public comments in a letter dated
August 20, 2015 (ADAMS Accession No. ML15204A383). On July 17, 2015,
the NRC approved the Permanently Defueled Technical Specifications for
SONGS, Units 2 and 3 (ADAMS Accession No. ML15139A390).
II. Request/Action
Pursuant to 10 CFR 140.8, ``Specific exemptions,'' SCE requested an
exemption from 10 CFR 140.11(a)(4), by letter dated September 16, 2015
(ADAMS Accession No. ML15260B188). The exemption from 10 CFR
140.11(a)(4) would permit the licensee to reduce the required level of
primary offsite liability insurance from $450 million to $100 million,
and would allow SCE to withdraw from participation in the secondary
layer of financial protection (also known as the industry retrospective
rating plan). The request to eliminate the requirement to carry
secondary financial protection is for SONGS, Units 2 and 3, only. The
NRC previously granted an exemption for SONGS, Unit 1, from the
requirements of 10 CFR 140.11(a)(4), which permitted SCE's withdrawal
from participation in the industry retrospective rating plan in 1994
(Legacy ADAMS Accession No. 9405090151).
The regulation at 10 CFR 140.11(a)(4) requires each licensee to
have and maintain primary financial protection in an amount of $450
million. In addition, the licensee is required to participate in an
industry retrospective rating plan (secondary financial protection)
that commits each licensee to pay into an insurance pool to be used for
damages that may exceed primary insurance coverage. Participation in
the industry retrospective rating plan will subject SCE to deferred
premium charges up to a maximum total deferred premium of $121,255,000
with respect to any nuclear incident at any operating nuclear power
plant, and up to a maximum annual deferred premium of $18,963,000 per
incident.
The licensee states that the risk of an offsite radiological
release is significantly lower at a nuclear power reactor that has
permanently shut down and defueled, when compared to an operating power
reactor. Similarly, the associated risk of offsite liability damages
that would require insurance or indemnification is commensurately lower
for permanently shut down and defueled plants. Therefore, SCE is
requesting an exemption from 10 CFR 140.11(a)(4), to permit a reduction
in primary offsite liability insurance and to withdraw from
participation in the industry retrospective rating plan.
III. Discussion
Pursuant to 10 CFR 140.8, the Commission may, upon application by
any interested person or upon its own initiative, grant exemptions from
the requirements of 10 CFR part 140, when the exemptions are authorized
by law and are otherwise in the public interest.
The Price-Anderson Act of 1957 (PAA) requires that nuclear power
reactor licensees have insurance to compensate the public for damages
arising from a nuclear incident. Specifically, the PAA requires
licensees of facilities with a ``rated capacity of 100,000 electrical
kilowatts or more'' to maintain the maximum amount of primary financial
protection that is commercially available (currently, $450 million)
with access to the aggregate amount of secondary financial protection
available to the industry (currently, up to $121,255,000 per reactor
covered by the rating plan totaling approximately $13 billion for the
industry per incident). The NRC's regulations at 10 CFR 140.11(a)(4)
implement these PAA requirements and set forth the amount of primary
and secondary financial protection that each power reactor licensee
must have.
As noted above, the PAA requirements with respect to primary and
secondary financial protection, and the implementing regulations at 10
CFR 140.11(a)(4), apply to licensees of facilities with a ``rated
capacity of 100,000 electrical kilowatts or more.'' When the NRC issues
a license amendment to a decommissioning licensee to reflect the
defueled status of the facility, the license amendment includes removal
of the rated capacity of the reactor from the license. Accordingly, a
reactor that is undergoing decommissioning has no ``rated capacity.''
Removal of the rated capacity from the facility of a
[[Page 1385]]
decommissioning licensee, thus, allows the NRC to take the reactor
licensee out of the category of reactor licensees that are required to
maintain the maximum available insurance and to participate in the
industry retrospective rating plan under the PAA, subject to a
technical finding that lesser potential hazards exist at the facility
after termination of operations.
The financial protection limits of 10 CFR 140.11(a)(4) were
established to require a licensee to maintain sufficient financial
protection, as specified under the PAA, to satisfy liability claims by
members of the public for personal injury, property damage, and the
legal cost associated with lawsuits, as the result of a nuclear
incident at an operating reactor with a rated capacity of 100,000
electric kilowatts (or greater). Thus, the financial protection levels
established by this regulation, and as required by the PAA, were
associated with the risks and potential consequences of an incident at
an operating reactor with a rated capacity of 100,000 electric
kilowatts (or greater). The legal and associated technical basis for
granting exemptions from 10 CFR part 140 is set forth in SECY-93-127.
The legal analysis underlying SECY-93-127 concluded that, upon a
technical finding that lesser potential hazards exist after termination
of operations (and removal of the rated capacity), the Commission has
the discretion under the PAA to reduce the amount of insurance required
of a licensee undergoing decommissioning.
As a technical matter, the fact that a reactor has permanently
ceased operations is not itself determinative as to whether a licensee
may cease providing the offsite financial protection coverage required
by the PAA and 10 CFR 140.11(a)(4). In light of the presence of freshly
discharged irradiated fuel in the spent fuel pool at a recently
shutdown reactor, the primary consideration is the risk and potential
consequence of an offsite radiological release from a zirconium fire.
That risk generally remains the greatest for a period of about 15 to 18
months of decay time for the fuel used in the last cycle of power
operation. After that time, the offsite consequences of an offsite
radiological release from a zirconium fire are negligible for shutdown
reactors, but the SFP is still operational and an inventory of
radioactive materials still exists onsite. Therefore, an evaluation of
the potential for offsite damage is necessary to determine the
appropriate level of offsite insurance post shutdown, in accordance
with the Commission's discretionary authority under the PAA to
establish an appropriate level of required financial protection for
such shutdown facilities.
The NRC staff has conducted an evaluation and concluded that, aside
from the handling, storage, and transportation of spent fuel and
radioactive materials for a permanently shut down and defueled reactor,
no reasonably conceivable potential incident exists that could cause
significant offsite damage. During normal power reactor operations, the
forced flow of water through the reactor coolant system (RCS) removes
heat generated by the reactor. The RCS, operating at high temperatures
and pressures, transfers this heat through the steam generator tubes
converting non-radioactive feedwater to steam, which then flows to the
main turbine generator to produce electricity. Many of the accident
scenarios postulated for operating power reactors involve failures or
malfunctions of systems that could affect the fuel in the reactor core,
which in the most severe postulated accidents, would involve the
release of large quantities of fission products. With the permanent
cessation of reactor operations at SONGS and the permanent removal of
the fuel from the reactor cores, such accidents are no longer possible.
The reactors, RCS, and supporting systems no longer operate and have no
function related to the storage of the irradiated fuel. Therefore,
postulated accidents involving failure or malfunction of the reactors,
RCS, or supporting systems are no longer applicable.
As described in the PSDAR, SONGS, Unit 1, is being returned to a
condition suitable for unrestricted use. According to SCE, there are no
structures, systems, or components (SSCs) classified as safety-related
remaining at SONGS, Unit 1. Plant dismantlement is complete and nearly
all of the SSCs have been shipped offsite for disposal. Only the spent
fuel, reactor vessel, and the below-grade portions of some buildings
remain onsite. The principal remaining decommissioning activities are
soil remediation, compaction, and grading. This is to be completed in
conjunction with the future decommissioning of the ISFSI subsequent to
offsite shipment of the spent fuel.
The licensee also stated that decommissioning of SONGS, Units 2 and
3, has begun and the nuclear reactors and essentially all associated
SSCs in the nuclear steam supply system and balance of plant that
supported the generation of power have been retired in place and are
being prepared for removal. The SSCs that remain operable are
associated with the SFPs and the spent fuel building, are needed to
meet other regulatory requirements, or are needed to support other site
facilities (e.g., radioactive waste handling, ventilation and air
conditioning, etc.). No remaining active SSCs are classified as safety-
related.
During reactor decommissioning, the principal radiological risks
are associated with the storage of spent fuel onsite. In addition, a
site with a permanently shutdown and defueled reactor may contain an
inventory of radioactive liquids, activated reactor components, and
contaminated materials. For purposes of modifying the amount of
financial protection maintained by a permanently shutdown and defueled
reactor licensee, the potential radiological consequences of these non-
operating reactor nuclear incidents are appropriate to consider,
despite their very low probability of occurrence. On a case-by-case
basis, licensees undergoing decommissioning have been granted
permission to reduce the required amount of primary offsite financial
protection from $450 million to $100 million, and to withdraw from the
industry retrospective rating plan.\1\ One of the technical criteria
for granting the exemption is elimination of the possibility of a
design-basis event that could cause significant offsite damage.
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\1\ See Memorandum from William D. Travers, Executive Director
for Operations, to the Commission, dated August 16, 2002 (ADAMS
Accession No. ML030550706).
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In its September 16, 2015, exemption request, SCE discusses both
design-basis and beyond design-basis events involving irradiated fuel
stored in the SFPs. The staff independently evaluated the offsite
consequences associated with various decommissioning activities, design
basis accidents, and beyond design basis accidents at SONGS, in
consideration of its permanently shut down and defueled status. The
possible design-basis and beyond design basis accident scenarios at
SONGS show that the radiological consequences of these accidents are
greatly reduced at a permanently shut down and defueled reactor, in
comparison to a fueled reactor. Further, the staff has used the offsite
radiological release limits established by the U.S. Environmental
Protection Agency (EPA) early-phase Protective Action Guidelines (PAGs)
of one roentgen equivalent man (rem) at the exclusion area boundary in
determining that any possible radiological releases would be minimal
and would not require precautionary protective actions (e.g.,
sheltering in place or evacuation), which could result in offsite
liability.
[[Page 1386]]
The only beyond design-basis event that has the potential to a
significant radiological release at a decommissioning reactor is a
zirconium fire. The zirconium fire scenario is a postulated, but highly
unlikely, beyond design-basis accident scenario that involves loss of
water inventory from the SFP, resulting in a significant heat-up of the
spent fuel, and culminating in substantial zirconium cladding oxidation
and fuel damage. The probability of a zirconium fire scenario is
related to the decay heat of the irradiated fuel stored in the SFP.
Therefore, the risks from a zirconium fire scenario continue to
decrease as a function of the time that SONGS has been permanently shut
down.
The licensee provided a detailed analysis of the events that could
result in an offsite radiological release at SONGS in its March 31,
2014, submittal to the NRC (ADAMS Accession No. ML14092A332), as
supplemented by letters dated September 9, October 2, October 7,
October 27, November 3, and December 15, 2014 (ADAMS Accession Nos.
ML14258A003, ML14280A265, ML14287A228, ML14303A257, ML14309A195, and
ML14351A078, respectively). One of these beyond design-basis accidents
involves a complete loss of SFP water inventory, where cooling of the
spent fuel would be primarily accomplished by natural circulation of
air through the uncovered spent fuel assemblies. The licensee's
analysis of this accident shows that by August 31, 2014, air-cooling of
the spent fuel assemblies will be sufficient to keep the fuel within a
safe temperature range indefinitely without fuel cladding damage or
offsite radiological release. The NRC staff has confirmed the reduced
risks at SONGS by comparing the generic risk assumptions in the
analyses in NUREG-1738, ``Technical Study of Spent Fuel Pool Accident
Risk at Decommissioning Nuclear Power Plants,'' dated February 28, 2001
(ADAMS Accession No. ML010430066) to site-specific conditions at SONGS;
based on this assessment, the staff determined that the risk values in
NUREG-1738 bound the risks presented by SONGS.
The Commission has previously authorized a lesser amount of
financial protection, based on an analysis of the zirconium fire risk.
In SECY-93-127, ``Financial Protection Required of Licensees of Large
Nuclear Power Plants during Decommissioning,'' dated May 10, 1993
(ADAMS Accession No. ML12257A628), the staff outlined a policy for
reducing required liability insurance coverage for decommissioning
reactors, and concluded that there was a low likelihood and reduced
short-term public health consequences of a zirconium fire once a
decommissioning plant's spent fuel has sufficiently decayed. The
discussions in SECY-93-127 centered primarily on the public health and
safety risks associated with storing fuel in spent fuel pools. In its
Staff Requirements Memorandum dated July 13, 1993 (ADAMS Accession No.
ML003760936), the Commission approved a policy that would permit
reductions in financial protection, when a licensee was able to
demonstrate that the spent fuel could be air-cooled if the SFP was
drained of water.
Upon demonstration of this technical criterion, the Commission
policy allowed decommissioning licensees to withdraw from participation
in the industry retrospective rating plan, and permitted reductions in
the required amount of primary financial protection from $450 million
to $100 million. The staff has used this technical criterion to grant
similar exemptions to other decommissioning reactor licensees (e.g.,
Maine Yankee Atomic Power Station, published in the Federal Register on
January 19, 1999 (64 FR 2920); and Zion Nuclear Power Station,
published in the Federal Register on December 28, 1999 (64 FR 72700)).
Additional discussions of other decommissioning reactor licensees that
have received exemptions to reduce their primary insurance level to
$100 million is provided in SECY-96-256, ``Changes to Financial
Protection Requirements for Permanently Shutdown Nuclear Power
Reactors, 10 CFR 50.54(w)(1) and 10 CFR 140.11,'' dated December 17,
1996 (ADAMS Accession No. ML15062A483). These prior exemptions were
based on the licensee demonstrating that the SFP could be air-cooled,
consistent with the technical criterion discussed above.
In SECY-00-0145, ``Integrated Rulemaking Plan for Nuclear Power
Plant Decommissioning,'' dated June 28, 2000, and SECY-01-0100,
``Policy Issues Related to Safeguards, Insurance, and Emergency
Preparedness Regulations at Decommissioning Nuclear Power Plants
Storing Fuel in the Spent Fuel Pool,'' dated June 4, 2001 (ADAMS
Accession Nos. ML003721626 and ML011450420, respectively), the staff
discussed additional information concerning SFP zirconium fire risks at
decommissioning reactors and associated implications for offsite
insurance. Analyzing when the spent fuel stored in the SFP is capable
of air-cooling is one measure that demonstrates when the probability of
a zirconium fire would be exceedingly low. However, the staff has more
recently used an additional analysis that would bound an incomplete
drain down of the SFP water, or some other catastrophic event (such as
a complete drainage of the SFP with rearrangement of spent fuel rack
geometry and/or the addition of rubble to the SFP). The analysis
postulates that decay heat transfer from the spent fuel via conduction,
convection, or radiation would be impeded. This analysis is often
referred to as an adiabatic heat-up analysis.
The licensee's analyses referenced in its exemption request
demonstrates that under conditions where the SFP water inventory has
drained completely and only air-cooling of the stored irradiated fuel
is available, after August 2014 air-cooling of the spent fuel
assemblies will be sufficient to keep the fuel within a safe
temperature range indefinitely without fuel cladding damage or offsite
radiological release. However, a portion of the air-cooling analyses
credits operation of the normal fuel building ventilation systems
because the fuel building structures are robust and offer little
potential for natural air exchange with the environment for cooling.
Because the normal fuel building ventilation could become unavailable
during an initiating event that would lead to complete SFP drainage
(i.e., a seismic event), the NRC staff also relied upon the additional
time that the fuel in the SONGS SFPs has had to cool since the plant
was permanently shutdown in June 2013 during its evaluation of the
licensee's exemption request.
As discussed in the staff response to a question in SECY-00-0145,
``the staff believes that full insurance coverage must be maintained
for 5 years or until a licensee can show by analysis that its spent
fuel pool is no longer vulnerable to such [a zirconium] fire.'' In
addition, as discussed in the staff response to another question in
SECY-00-0145:
Since the zirconium fire scenario would be possible for up to
several years following shutdown, and since the consequences of such
a fire could be severe in terms of offsite health consequences,
property damage, and land contamination, the staff position is that
full offsite liability coverage (both primary and secondary levels)
must be retained for five years or until analysis has indicated that
a zirconium fire is no longer possible. At that point, primary
coverage would be reduced from $200 million to $100 million and
participation in the secondary retrospective rating pool would no
longer be required.
Although the official certifications for permanent cessation of power
operations and permanent removal of fuel from the reactor vessel were
not submitted until June 2013, the staff notes that SONGS was in an
extended
[[Page 1387]]
outage to address steam generator issues, and neither SONGS, Units 2
nor 3, have produced power since January 2012. This additional storage
time for the fuel in the SONGS SFPs has allowed it to cool for greater
than the 5 years suggested in SECY-00-0145, which supports the
conclusion that zirconium fire risks from the irradiated fuel stored in
the SFPs is of negligible concern and exemption from the requested
requirements is warranted.
In addition to the air-cooling scenario, the licensee's adiabatic
heat-up analyses demonstrate that as of October 12, 2014, there would
be at least 17 hours after the loss of all means of cooling (both air
and/or water), before the spent fuel cladding would reach a temperature
where the potential for a significant offsite radiological release
could occur. The licensee states that for this loss of all cooling
scenario, 10 hours is sufficient time for personnel to respond with
additional resources, equipment, and capability to restore cooling to
the SFPs, even after a non-credible, catastrophic event.
As provided in SCE's letters dated October 7 and December 15, 2014,
the licensee furnished information concerning its makeup strategies, in
the event of a loss of SFP coolant inventory. The multiple strategies
for providing makeup to the SFPs include: Using existing plant systems
for inventory makeup; an internal strategy that relies on installed
fire water pumps and service water or fire water storage tanks; or an
external strategy that uses portable pumps to initiate makeup flow into
the SFPs through a seismic standpipe and standard fire hoses routed to
the SFPs or to a spray nozzle. These strategies will be maintained by a
license condition until such time as all fuel has been moved to dry
storage in an onsite ISFSI. The licensee states that the equipment
needed to perform these actions are located onsite, and that the
external makeup strategy (using portable pumps) is capable of being
deployed within 2 hours. The licensee also stated that, considering the
very low-probability of beyond design-basis accidents affecting the
SFPs, these diverse strategies provide defense-in-depth and time to
mitigate and prevent a zirconium fire, using makeup or spray into the
SFP before the onset of zirconium cladding rapid oxidation.
In the safety evaluation of the licensee's request for exemptions
from certain emergency planning requirements dated June 4, 2015 (ADAMS
Accession No. ML15082A204), the NRC staff assessed the SCE accident
analyses associated with the radiological risks from a zirconium fire
at the permanently shutdown and defueled SONGS site. The NRC staff has
confirmed that under conditions where cooling air flow can develop,
suitably conservative calculations indicate that by the end of August
2014, the fuel would remain at temperatures where the cladding would be
undamaged for an unlimited period. The staff also finds that the
additional cooling time provided for the fuel between January 2012 and
the issuance of this exemption provides reasonable assurance that
zirconium fire risks from the irradiated fuel stored in the SFPs is of
negligible concern. For the very unlikely beyond design-basis accident
scenario, where the SFP coolant inventory is lost in such a manner that
all methods of heat removal from the spent fuel are no longer
available, there will be a minimum of 10 hours from the initiation of
the accident until the cladding reaches a temperature where offsite
radiological release might occur. The staff finds that 10 hours is
sufficient time to support deployment of mitigation equipment,
consistent with plant conditions, to prevent the zirconium cladding
from reaching a point of rapid oxidation.
The NRC staff has determined that the licensee's proposed reduction
in primary offsite liability coverage to a level of $100 million, and
the licensee's proposed withdrawal from participation in the secondary
insurance pool for offsite financial protection, are consistent with
the policy established in SECY-93-127 and subsequent insurance
considerations, resulting from additional zirconium fire risks, as
discussed in SECY-00-0145 and SECY-01-0100. The NRC has previously
determined in SECY-00-0145 that the minimum offsite financial
protection requirement may be reduced to $100 million and that
secondary insurance is not required, once it is determined that the
spent fuel in the spent fuel pool is no longer thermal-hydraulically
capable of sustaining a zirconium fire based on a plant-specific
analysis. In addition, the NRC staff notes that similar exemptions have
been granted to other permanently shutdown and defueled power reactors,
upon demonstration that the criterion of the zirconium fire risks from
the irradiated fuel stored in the SFP is of negligible concern.
Finally, the staff notes that in accordance with the SONGS PSDAR, all
spent fuel will be removed from the SFPs and moved into dry storage at
an onsite ISFSI by the end of 2019, and the probability of an
initiating event that would threaten SFP integrity occurring before
that time is extremely low, which further supports the conclusion that
the risk of a zirconium fire is negligible.
The Exemption Is Authorized by Law
In accordance with 10 CFR 140.8, the Commission may grant
exemptions from the regulations in 10 CFR part 140 as the Commission
determines are authorized by law. The NRC staff has determined that
granting the licensee's proposed exemption will not result in a
violation of the Atomic Energy Act of 1954, Section 170, as amended,
other laws, or the Commission's regulations, which require licensees to
maintain adequate financial protection. Therefore, the proposed
exemption for SONGS from the primary offsite liability insurance and
secondary financial protection requirements of 10 CFR 140.11(a)(4) is
authorized by law.
The Exemption Is Otherwise in the Public Interest
The financial protection limits of 10 CFR 140.11 were established
to require licensees to maintain sufficient offsite liability insurance
to ensure adequate funding for offsite liability claims, following an
accident at an operating reactor. However, the regulation does not
consider the reduced potential for and consequences of nuclear
incidents at permanently shutdown and decommissioning reactors.
In SECY-93-127, SECY-00-0145, and SECY-01-0100 provide a basis for
allowing licensees of decommissioning plants to reduce their primary
offsite liability insurance and to withdraw from participation in the
retrospective rating pool for deferred premium charges. As discussed in
these documents, once the zirconium fire concern is determined to be
negligible, possible accident scenario risks at permanently shutdown
and defueled reactors are greatly reduced, when compared to operating
reactors, and the associated potential for offsite financial
liabilities from an accident are commensurately less. The licensee has
analyzed and the staff has confirmed that the possible accidents that
could result in an offsite radiological risk are minimal, thereby
justifying the proposed reductions in offsite liability insurance and
withdrawal from participation in the secondary retrospective rating
pool for deferred premium charges.
Additionally, participation in the secondary retrospective rating
pool could be problematic for SCE because the licensee would incur
financial liability if an extraordinary nuclear incident occurred at
another nuclear power plant. Because SONGS is permanently shut down, it
does not
[[Page 1388]]
produce revenue from electricity generation sales to cover such a
liability. Therefore, such liability, if incurred, could significantly
affect the financial resources available to the facility to conduct and
complete radiological decontamination and decommissioning activities.
Furthermore, the shared financial risk exposure to SCE is greatly
disproportionate to the radiological risk posed by SONGS when compared
to operating reactors.
The reduced overall risk to the public at decommissioning power
plants does not warrant SCE to carry full operating reactor insurance
coverage, after the requisite spent fuel cooling period has elapsed,
following final reactor shutdown. The licensee's proposed financial
protection limits will maintain a level of liability insurance coverage
commensurate with the risk to the public. These changes are consistent
with previous NRC policy and exemptions approved for other
decommissioning reactors. Thus, the underlying purpose of the
regulations will not be adversely affected by reductions in the
insurance coverage for SONGS.
Accordingly, the proposed exemption for SONGS from the primary
offsite liability insurance and secondary financial protection
requirements of 10 CFR 140.11(a)(4) is in the public interest.
Environmental Considerations
Pursuant to 10 CFR 51.22(c)(25), the granting of an exemption from
the requirements of any regulation in Chapter I of 10 CFR is a
categorical exclusion provided that (i) there is no significant hazards
consideration; (ii) there is no significant change in the types or
significant increase in the amounts of any effluents that may be
released offsite; (iii) there is no significant increase in individual
or cumulative public or occupational radiation exposure; (iv) there is
no significant construction impact; (v) there is no significant
increase in the potential for or consequences from radiological
accidents; and (vi) the requirements from which an exemption is sought
are among those identified in 10 CFR 51.22(c)(25)(vi).
The NRC staff has determined that approval of the exemption request
involves no significant hazards consideration because reducing the
licensee's offsite liability requirements at the decommissioning San
Onofre Nuclear Generating Station, Units 2 and 3, does not (1) involve
a significant increase in the probability or consequences of an
accident previously evaluated; (2) create the possibility of a new or
different kind of accident from any accident previously evaluated; or
(3) involve a significant reduction in a margin of safety. The exempted
financial protection regulation is unrelated to the operation of SONGS.
Accordingly, there is no significant change in the types or significant
increase in the amounts of any effluents that may be released offsite,
and no significant increase in individual or cumulative public or
occupational radiation exposure.
The exempted regulation is not associated with construction, so
there is no significant construction impact. The exempted regulation
does not concern the source term (i.e., potential amount of radiation
involved an accident) or accident mitigation; therefore, there is no
significant increase in the potential for, or consequences from, a
radiological accident. In addition, there would be no significant
impacts to biota, water resources, historic properties, cultural
resources, or socioeconomic conditions in the region. The requirement
for offsite liability insurance may be viewed as involving surety,
insurance, or indemnity matters in accordance with 10 CFR
51.22(c)(25)(vi).
Therefore, pursuant to 10 CFR 51.22(b) and 10 CFR 51.22(c)(25), no
environmental impact statement or environmental assessment need be
prepared in connection with the approval of this exemption request.
IV. Conclusions
Accordingly, the Commission has determined that, pursuant to 10 CFR
140.8, the exemption is authorized by law, and is otherwise in the
public interest. Therefore, the Commission hereby grants SCE exemption
from the requirement of 10 CFR 140.11(a)(4) to permit the licensee to
reduce primary offsite liability insurance to $100 million, accompanied
by withdrawal from participation in the secondary insurance pool for
offsite liability insurance.
This exemption is effective upon issuance.
Dated at Rockville, Maryland, this 5th day of January 2018.
For the Nuclear Regulatory Commission.
Gregory Suber,
Deputy Division Director, Division of Decommissioning, Uranium Recovery
and Waste Programs, Office of Nuclear Material Safety and Safeguards.
[FR Doc. 2018-00318 Filed 1-10-18; 8:45 am]
BILLING CODE 7590-01-P