[Federal Register Volume 61, Number 121 (Friday, June 21, 1996)]
[Notices]
[Pages 31964-31966]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-15838]
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NUCLEAR REGULATORY COMMISSION
[Docket Nos. 50-029, 50-312, 50-344, 50-206; License Nos. DPR-3, DPR-
54, NPF-1, DPR-13]
Yankee Atomic Electric Co., Sacramento Municipal Utility
District, Portland General Electric Co., and Southern California Edison
Co.; Receipt of a Petition for, and Issuance of, a Director's Decision
under 10 CFR 2.206
Notice is hereby given that by a letter dated April 1, 1996,
Citizens Awareness Network, Nuclear Information and Resource Service,
and nine other organizations \1\ (Petitioners) requested action
pursuant to 10 CFR 2.206 to modify the possession-only licenses of the
Yankee Nuclear Power Station (or Yankee Rowe), Rancho Seco Nuclear
Generating Station, Trojan Nuclear Plant, and San Onofre Nuclear
Generating Station, Unit 1, licensed respectively to the Yankee Atomic
Electric Company (YAEC), Sacramento Municipal Utility District,
Portland General Electric Company, and Southern California Edison
Company (Licensees). The Petitioners request that the U.S. Nuclear
Regulatory Commission (NRC) take emergency action to require a
collaborative effort by the licensees of the four nuclear power plants
to document and research radiation embrittlement of reactor pressure
vessels (RPVs) as an age-related deterioration phenomenon.
Specifically, Petitioners request that the NRC: (1) Suspend the current
plan by Yankee Atomic Electric Company (YAEC) for the removal,
transport, and burial of the Yankee Rowe RPV; (2) require the licensees
of the four permanently closed reactors, who are now developing plans
to remove, transport, and bury their respective RPVs, to suspend such
operations; and (3) require the owners of the four nuclear power plants
to present substantial metal and weld specimens from their respective
RPVs to the NRC for analysis in order to study and materially archive
the radiation embrittlement phenomenon.
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\1\ Don't Waste Oregon Council, Greenpeace, Environmental
Coalition on Nuclear Power, Friends of the Coast Opposing Nuclear
Pollution, New England Coalition Against Nuclear Pollution, Ohio
Citizens for Responsible Energy, Physicians for Social
Responsibility, the Redwood Alliance, and the Westchester People's
Action Coalition.
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As bases for their requests, Petitioners state that: (1) The four
permanently closed reactors constitute a valuable asset for evaluating
RPV embrittlement, (2) ``boat'' or scoop samples from the RPV could be
retrieved with minimal occupational radiation exposure, (3) data from
boat samples could be used to verify the veracity of simulated
[[Page 31965]]
embrittlement in research reactors, and (4) boat samples could be
subjected to annealing or reheating processes to analyze the results
for restoring ductility of the material and for determining the
durability of an annealing process.
Notice is also hereby given that by a Director's Decision (DD 96-
07) dated June 14, 1996, the Director, Office of Nuclear Reactor
Regulation, has denied the petition. The NRC staff has concluded that
sufficient information is already and will be available to the staff to
satisfactorily and timely address such radiation embrittlement
phenomenon in a manner which protects public health and safety, as
explained in the ``Director's Decision Pursuant to 10 CFR 2.206'' (DD
96-07), the complete text of which follows this notice and is available
for inspection at the Commission's Public Document Room at 2120 L
Street, NW., Washington, DC, and at the local public document room
located at the Greenfield Community College Library, 1 College Drive,
Greenfield, Massachusetts; the Central Library, Government Documents,
828 I Street, Sacramento, California; the Branford Price Millar
Library, Portland State University, Portland, Oregon; the Science
Library, University of California, Irving, California.
Dated at Rockville, MD, this 14th day of June 1996.
For the Nuclear Regulatory Commission.
Frank J. Miraglia,
Acting Director, Office of Nuclear Reactor Regulation.
Appendix to Receipt of a Petition for, and Issuance of, a Director's
Decision Under 10 CFR 2.206
Office of Nuclear Reactor Regulation
In the Matter of: Yankee Atomic Electric Company (Yankee Nuclear
Power Station), Docket No. 50-029, License No. DPR-3; Sacramento
Municipal Utility District (Rancho Seco Nuclear Generating Station),
Docket No. 50-312, License No. DPR-54; Portland General Electric
Company (Trojan Nuclear Plant), Docket No. 50-344, License No. NPF-
1; Southern California Edison Company (San Onofre Nuclear Generating
Station, Unit 1), Docket No. 50-206, License No. DPR-13.
I. Introduction
Citizens Awareness Network, Nuclear Information and Resource
Service and nine other organizations \1\ (Petitioners) submitted a
Petition dated April 1, 1996, pursuant to Sec. 2.206 of Title 10 of
the Code of Federal Regulations (10 CFR), requesting that the U.S.
Nuclear Regulatory Commission (NRC) take action with regard to the
Yankee Nuclear Power Station (or Yankee Rowe, licensed to the Yankee
Atomic Electric Company), Rancho Seco Nuclear Generating Station
(licensed to the Sacramento Municipal Utility District), Trojan
Nuclear Plant (licensed to the Portland General Electric Company),
and San Onofre Nuclear Generating Station, Unit 1 (licensed to the
Southern California Edison Company). These four power reactors have
permanently ceased operation and are in various stages of
decommissioning.
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\1\ Don't Waste Oregon Council, Greenpeace, Environmental
Coalition on Nuclear Power, Friends of the Coast Opposing Nuclear
Pollution, New England Coalition Against Nuclear Pollution, Ohio
Citizens for Responsible Energy, Physicians for Social
Responsibility, the Redwood Alliance, and the Westchester People's
Action Coalition.
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Petitioners request that the NRC take emergency action to
require a collaborative effort by the licensees of the four power
reactors to document and research radiation embrittlement of reactor
pressure vessels (RPVs) as an age-related deterioration phenomenon
because an archive is essential in understanding the issues
surrounding embrittlement of reactor vessels. Specifically, the
petitioners request that the NRC (1) suspend the current plan by
Yankee Atomic Electric Corporation (YAEC) for the removal,
transport, and burial of the Yankee Rowe RPV; (2) require licensees
of the four permanently closed reactors, who are now developing
plans to remove, transport, and bury their respective RPVs to
suspend such operations; and (3) require the owners of the four
nuclear power plants to present substantial metal and weld specimens
from their respective RPVs to the NRC for analysis in order to study
and materially archive the radiation embrittlement phenomena.
As bases for their requests, Petitioners state that (1) the four
permanently closed reactors constitute a valuable asset for
evaluating RPV embrittlement, (2) ``boat'' or scoop samples from the
RPV could be retrieved with minimal occupational radiation exposure,
(3) data from boat samples could be used to verify the veracity of
simulated embrittlement in research reactors, and (4) boat samples
could be subjected to annealing or reheating processes to analyze
the results for restoring ductility of the material and for
determining the durability of an annealing process.
For the reasons explained below, Petitions request is denied.
II
Irradiation of the reactor pressure vessel materials adjacent to
the reactor core (the beltline materials), by neutrons escaping from
the reactor core leads to embrittlement of those materials. This
embrittlement phenomena causes the reactor pressure vessel to be
more susceptible to fracture when subjected to operational or
accident transients that cause overcooling (thermal shock)
concurrent with or followed by significant pressure in the reactor
vessel. Concern over this phenomenon has resulted in the NRC
developing regulations to closely monitor embrittlement of reactor
vessels. Additionally, to better understand and qualify the
embrittlement process, the NRC Office of Research has a reactor
pressure vessel safety research program that addresses the
embrittlement phenomenon on a broad basis.
III
The NRC staff has concluded that sufficient information already
is and will be available to the staff in order to address radiation
embrittlement phenomena in a manner which protects public health and
safety, without ordering any of the four licensees to suspend
decommissioning plans or decommissioning activities to supply metal
and weld RPV samples for study. In addition to studying monitoring
data which all licensees are required to supply, the staff has
tested and will continue to test material from several sources as
part of its confirmatory research program. Samples obtained from
decommissioned reactor pressure vessels already do and will continue
to supplement other embrittlement data.
Licensees are required by 10 CFR 50.61 and appendix H, ``Reactor
Vessel Material Surveillance Program Requirements,'' to monitor RPV
embrittlement. Appendix H specifies requirements for material
surveillance programs to monitor changes in the fracture toughness
of ferritic materials in the RPV beltline region from exposure of
these materials to neutron radiation. This regulation requires each
licensee to monitor neutron irradiation embrittlement by placing
weld and/or base materials (either plate or forging) that are
representative of its beltline materials in capsules that are placed
inside the RPV. Most plants have plant-specific surveillance
programs under which the capsules are irradiated in the licensee's
RPV. Some licensees are participating in integrated surveillance
programs under which the capsules are irradiated in a vessel that
has an irradiation and thermal environment equivalent to that of the
licensee's RPV. The capsules are periodically withdrawn from the RPV
and the materials tested to monitor the effect of neutron radiation
on the fracture toughness of the vessel beltline materials. These
programs have been reviewed by the staff and are sufficient for
monitoring the effect of neutron radiation at all operating light
water reactors.
In addition to licensee programs, the NRC is sponsoring a number
of other programs. NRC confirmatory research programs in which
materials are irradiated in test reactors, and the effect of neutron
radiation on the fracture toughness of beltline materials is
analyzed, are the Heavy Section Steel Irradiation Program, the
Radiation Embrittlement and Prediction Program, the Improved
Radiation Embrittlement Correlation Program, and the Embrittlement
Database and Dosimetry Evaluation Program. In the Improved Radiation
Embrittlement Correlation and the Embrittlement Database and
Dosimetry Evaluation Programs, the staff accumulates and evaluates
data from power reactor licensee and test reactor programs and
determines the effect of neutron radiation on the fracture toughness
of beltline welds, forgings, and plates. In connection with these
issues, the staff has documented in Regulatory Guide 1.99, Revision
2, ``Radiation Embrittlement of Reactor Vessel Materials,'' a
methodology for determining the effect of neutron radiation on
reactor vessel welds, forgings, and plates. The methodology in
Regulatory Guide 1.99 includes a margin term to account for the
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uncertainties in the material properties and the radiation
environment. As the NRC staff accumulates more surveillance data
from licensees, it periodically evaluates the data to determine
whether the Regulatory Guide 1.99 methodology needs revision. The
licensee surveillance database consists of data from several hundred
licensee capsules.
The Heavy Section Steel Irradiation Program provides
experimental evaluation of the effects of chemistry and radiation
environment on the irradiation embrittlement of reactor pressure
vessel steels, including the effects of thermal aging, recovery of
fracture toughness by thermal annealing, and reembrittlement trends
on annealed reactor vessel materials. This program, in conjunction
with the Radiation Embrittlement and Prediction Program, is
developing improved methods for predicting irradiation
embrittlement. Both programs are evaluating, experimentally and
analytically, the mechanisms that control irradiation embrittlement
to justify extrapolation of the empirical model to predict plant-
specific irradiation embrittlement. These programs are validating
the analytical and empirical models through the testing of service
degraded reactor vessel materials.
The NRC staff's recommended methodology for determining the
effect of thermal annealing on RPV embrittlement is documented in
Regulatory Guide 1.162, ``Format and Content of Report for Thermal
Annealing of Reactor Pressure Vessels.'' NUREG/CR-6327, ``Models for
Embrittlement Recovery due to Annealing of Reactor Pressure Vessel
Steels,'' contains the data and evaluation that form the bases for
the percent recovery of radiation embrittlement from thermal
annealing that is documented in Regulatory Guide 1.162. The thermal
annealing rule, 10 CFR 50.66, requires that each licensee performing
a thermal anneal must monitor the post-anneal reembrittlement trend
using a surveillance program that conforms with the intent of
appendix H. The effect of thermal annealing on RPV embrittlement is
adequately addressed by requiring licensees to monitor the post-
anneal reembrittlement trend through a surveillance program and by
use of the Regulatory Guide 1.162 methodology.
Based on analysis performed by licensees and the NRC, the staff
has concluded that the overall integrity analyses, including the
various margins, are conservative and that they provide reasonable
assurance that the vessels can withstand normal operation and
accident conditions. Furthermore, each licensee must bear the burden
of demonstration the adequacy of its pressure vessel to withstand
the effects of a transient causing overcooling concurrent with or
followed by significant pressure when the methodology of Regulatory
Guide 1.99, Revision 2, does not predict an acceptable result.
Should a licensee not be able to demonstrate, or be unwilling to
expend the resources to demonstrate, the adequacy of its pressure
vessel (which may include actual samples of base material), the
plant must be shutdown as was the case for Yankee Rowe.
Test material from the Yankee Rowe pressure vessel would not be
of value in estimating the level of embrittlement, thermal annealing
recovery, and reembrittlement after annealing at currently operating
U.S. facilities. The Yankee Rowe reactor operated at a lower
temperature than typical of operating plants, making any data on
embrittlement from Yankee Rowe difficult to correlate with other
light water reactor designs in the U.S.
Samples from the Rancho Seco vessel would not provide useful
information since equivalent weld material and vessel wall samples
are available from the Babcock and Wilcox Owners Group and from the
canceled Midland Nuclear Plant. These samples are currently being
evaluated in a program that irradiates the samples in test reactors.
These components and samples, taken from power reactors and
irradiated in test reactors, will provide data that could be
correlated to other sample research programs that utilize research
reactors.
The licensee for the San Onofre 1 reactor has submitted a
decommissioning plan to the NRC that proposes SAFSTOR, or long-term
storage of the facility, until the licenses for San Onofre Units 2
and 3 expire, sometime after 2013. Therefore, the Unit 1 vessel will
remain onsite and in a condition that would allow samples of test
material to be obtained for a substantial period of time, should it
be determined that such samples would be useful for study.
The Trojan Nuclear Plant is currently undergoing active
dismantlement. Portland General Electric, the licensee, is planning
to remove the reactor vessel and dispose of it at the Hanford,
Washington low-level burial site no earlier than 1998. The staff
currently is pursuing the possibility of obtaining samples from the
reactor vessel once the reactor vessel reaches the burial site.
For the above reasons, the staff concludes that sufficient
information is already and will be available to appropriately and
timely address the radiation embrittlement phenomenon.
IV. Conclusion
the Petitioners have not provided sufficient bases to warrant
the suspension of decommissioning plans or activities at the four
nuclear power plants in order to take specimens of reactor vessels
for the purpose of studying nuclear power reactor pressure vessels
radiation embrittlement phenomena. Moreover, as explained above,
sufficient information is available to the staff to address such
radiation embrittlement phenomena in a manner which protects public
health and safety without the issuance of an order. Accordingly, for
the reasons discussed above, the Petition, including the request to
take emergency actions is denied.
A copy of this Director's Decision will be filed with the Office
of the Secretary for the Commission to review in accordance with 10
CFR 2.206(c). As provided by Sec. 2.206(c), this decision will
constitute the final action of the Commission 25 days after
issuance, unless the Commission, on its own motion, institutes a
review of the decision within that time.
Dated at Rockville, MD, this 14th day of June 1996.
Frank J. Miraglia,
Acting Director, Office of Nuclear Reactor Regulation.
[FR Doc. 96-15838 Filed 6-20-96; 8:45 am]
BILLING CODE 7590-01-M
