[Federal Register Volume 74, Number 29 (Friday, February 13, 2009)]
[Notices]
[Pages 7271-7273]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E9-3143]
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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-285;NRC-2008-0670]
Omaha Public Power District, Fort Calhoun Station, Unit No. 1.;
Exemption
1.0 Background
Omaha Power Public District (OPPD, the licensee) is the holder of
Renewed Facility Operating License No. DPR-40, which authorizes
operation of the Fort Calhoun Station (FCS), Unit No. 1. The license
provides, among other things, that the facility is subject to all
rules, regulations, and orders of the Nuclear Regulatory Commission
(NRC, the Commission) now or hereafter in effect.
The facility consists of a Combustion Engineering pressurized
light-water reactor located in Washington County, Nebraska.
2.0 Request/Action
FCS, Unit No. 1 was licensed to operate prior to January 1, 1979.
As such, the licensee's Fire Protection Program must satisfy the
established fire protection features of Title 10, ``Energy,'' of the
Code of Federal Regulations (10 CFR), Part 50, Appendix R, ``Fire
Protection Program for Nuclear Power Facilities Operating Prior to
January 1, 1979,'' per 10 CFR 50.48, ``Fire protection,'' Section (b),
regulatory requirements.
By letter dated February 4, 2008 (Agencywide Documents Access and
Management System (ADAMS) Accession No. ML080360106), OPPD, on behalf
of FCS, Unit No. 1, requested an exemption from the provisions of 10
CFR Part 50, Appendix R, Section III.G.1.b (III.G.1.b), for the 72-hour
requirement to provide repair procedures and materials for cold
shutdown capability for redundant cold shutdown components.
The proposed exemption request addresses the power and control
cables for the four raw water pumps that are routed from the auxiliary
building through outside cable pull boxes 128T and 129T into the
underground duct bank and manhole vault numbers 5 and 31 into the
intake structure building.
The intake structure building at FCS provides river water to
various safety and non-safety-related components throughout the plant.
This building is separate from the main body of the plant and is
located on the riverbank to the east of the turbine building. Major
components located in the intake structure building are three
circulating water pumps, four safety-related raw water pumps, and two
fire pumps. The redundant safety-related raw water pumps, necessary for
cold shutdown functions only, are located in a common fire area in the
intake structure building, Fire Area 31.
3.0 Discussion
Pursuant to 10 CFR 50.12, the Commission may, upon application by
any interested person or upon its own initiative, grant exemptions from
the requirements of 10 CFR Part 50 when (1) the exemptions are
authorized by law, will not present an undue risk to public health or
safety, and are consistent with the common defense and security; and
(2) when special circumstances are present. One of these special
circumstances, described in 10 CFR 50.12(a)(2)(ii), is when application
of the regulation in the particular circumstances would not serve the
underlying purpose of the rule, or is not necessary to achieve the
underlying purpose of the rule.
By letter dated July 3, 1985 (ADAMS Legacy Library Accession No.
850724390), the NRC granted an exemption from the technical
requirements of Section III.G.2 of Appendix R to 10 CFR Part 50, for
Fire Area 31 (intake structure building) and for the pull box area of
the auxiliary building. However, cables in the duct bank and manhole
vault numbers 5 and 31 that are routed between the pull boxes and
intake structure were not discussed in the OPPD August 30, 1983,
exemption request (ADAMS Legacy Library Accession No. 830909011).
The OPPD letter dated February 4, 2008, clarified that the NRC July
3, 1985, safety evaluation report (SER) incorrectly referenced Section
III.G.2 and subsequently provided exemption from 10 CFR Part 50,
Section III.G. Specifically, the OPPD letter of February 4, 2008,
states that ``This exemption request thereby provides notification and
clarification that the original SER and exemption should have
referenced 10 CFR 50, Appendix R, Section III.G.1.b * * *'' Therefore,
the NRC staff evaluation in this SER supersedes the reference ``Section
III.G.2'' used in the NRC SER dated July 3, 1985, for Fire Area 31
(intake structure building and pull boxes 128T and 129T outside the
auxiliary building). OPPD has identified the duct bank and manhole
vault numbers 5 and 31 as part of the Fire Area 31; therefore, the NRC
staff evaluation in this SER includes exemption from 10 CFR Part 50,
Appendix R, Section III.G.1.b for duct bank and manhole vault numbers 5
and 31.
OPPD justified the exemption in duct bank and manhole vault numbers
5 and 31 based on the limited combustible loading (other than cable and
cable insulation) and limited ignition sources. OPPD has determined
that there is no credible threat from a fire occurring in the area of
the cable duct bank or manhole vaults that would disable all trains of
raw water and prevent the safe shutdown of the plant. The raw water
system will remain available to achieve post-fire cold shutdown within
72 hours.
The NRC staff's review of the February 4, 2008, OPPD proposed
license exemption request identified areas in which additional
information was necessary to complete the review. By e-mail dated
September 17, 2008 (ADAMS Accession No. ML083360264), the NRC staff
sent a request for additional information (RAI) to OPPD. OPPD responded
by letter dated October 13, 2008 (ADAMS Accession No. ML082980018), as
discussed below.
The NRC staff requested the licensee to provide a description of
the defense-in-depth features in the underground duct bank and manhole
vault numbers 5 and 31. The licensee responded that there is no
ignition source in the duct bank or manhole vaults, other than the
remote possibility of a self-ignited cable fault. The duct bank and
manhole vaults are classified as a confined space and, therefore, entry
is not allowed without appropriate permits and controls that minimize
the potential for introducing transient ignition or combustible
materials. Further, hot work performed in the duct bank and manhole
vaults is
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conducted in accordance with Standing Order (SO)-M-9 and FCS Guidance
(FCSG)-15-35, which require the protection of electrical cables located
within 35 feet of the welding or cutting location. The licensee
indicated in its response that there are no means of automatic fire
detection or suppression in the duct bank and manhole vaults. However,
if a fire did occur, operators in the control room would have
indications of equipment faults (e.g., tripping of operating pumps,
off-normal valve indication lights, etc.) and would rapidly begin to
investigate the cause and location of the fault. The duct bank and
manhole vaults are located inside the protected area in close proximity
to the power block. Should a fire occur as a result of hot work in the
duct bank and/or manhole vaults, the craft or fire watch would
immediately contact the control room, and the fire brigade would be
dispatched to extinguish the fire. OPPD has indicated that prior to
beginning hot work, form FC-18, ``Hot Work Permit,'' is completed and a
copy given to the Operations Control Center (OCC). Form FC-18 contains
numerous steps to prevent, detect, and respond to a fire. The steps
include protecting areas such as electrical cabling located within 35
feet of the welding or cutting location. A trained individual is
designated fire watch both during and for 30 minutes after the hot work
is completed. The fire watch monitors the work area, adjacent areas,
and above and below the work area. The fire watch is trained to
immediately report fires to the control room and is equipped with a
fire extinguisher to extinguish small fires, if possible.
The NRC staff requested the licensee to clarify if, in FCS, Unit
No. 1 abnormal operating procedures (AOPs), post-fire safe shutdown
analysis assumes all equipment available during a postulated fire. In
addition, the NRC staff requested that the licensee confirm that the
post-fire safe shutdown analysis emergency operating procedures (EOPs)
do not rely solely on ``feed and bleed'' as the means of protecting the
core. The licensee responded that the FCS, Unit No. 1, post-fire safe
shutdown analysis (Engineering Analysis (EA)-FC-89-055) assumes all
equipment credited for a given fire area is available during a
postulated fire. FCS does not rely solely on once-through cooling (or
``feed and bleed'') as a means of heat removal to protect the reactor
core in a post-fire safe shutdown scenario. Options for reactor coolant
system (RCS) heat removal in FCS EOP-20, ``Functional Recovery
Procedure,'' include: (1) RCS and core heat removal via steam
generators with no safety injection, (2) RCS and core heat removal via
steam generators with safety injection operating, (3) shutdown cooling
operation, and (4) feed and bleed (or once-through cooling). Although
feed and bleed is one of the EOP-20 options, it is the least desirable
and would only be utilized if other means are unavailable or have
failed for the given plant conditions. FCS, Unit No. 1, does not have a
specific EOP for post-fire safe shutdown. For a fire within the
protected area, FCS implements AOP-06, ``Fire Emergency.'' Based on the
extent of fire damage, location of the fire and plant response to the
fire, control room operators have the option to implement EOPs to
achieve safe shutdown conditions.
The NRC staff requested the licensee to clarify and confirm that
the types of combustibles have not changed and total combustible
loading in the intake structure building has not increased, and that
there is no change in active and passive fire protection features as
last described in the OPPD license exemption request dated August 30,
1983. Further, the NRC staff requested that, if there has been a change
in the types of combustibles or there is an increase in combustible
load or change in fire protection features in the intake structure
building, then OPPD should provide details and a basis for why the
change remains acceptable. In addition, the NRC staff asked the
licensee to confirm that the pyrocrete enclosure is in place to protect
the cables for raw water pumps AC-10A and AC-10B from fire in the
intake structure building. The licensee responded that the type of
combustible material in the duct bank and manhole vaults is limited to
cable insulation. This has not changed since original plant
construction. Any change in the total combustible loading since August
30, 1983, for the duct bank, manhole vaults, and/or intake structure
would have been evaluated for impact in the combustible loading
calculation (FC05814), which is the controlled design calculation that
maintains an accounting of combustible load for fire areas at FCS, Unit
No. 1. Further, the licensee has indicated that the review of previous
revisions of this calculation confirms that total combustible loading
has remained classified as low and no significant changes in total
loading have occurred. Therefore, the basis for this reference remains
valid. The pyrocrete enclosure remains in place to protect cables
associated with pumps AC-10A and AC-10B from a fire in the intake
structure. This enclosure is inspected by a fire barrier surveillance
test on an 18-month interval.
Based on the above, the consequences of postulated accidents are
not increased, because there is no credible fire hazard in the area of
the cable duct bank or manhole vaults that would disable all the raw
water pumps and prevent the cold shutdown capability. Furthermore, if
all raw water pumps are lost, due to any condition, the AOP directs the
operator to trip the reactor and enter emergency procedures based on
observed plant conditions. Therefore, there is no undue risk to public
health and safety, since neither the probability nor the consequences
have been increased.
On the basis of its review and evaluation of the information
provided in the licensee's exemption request and response to NRC staff
RAI questions, the NRC staff concludes that OPPD's request for
exemption from the technical requirements of Section III.G.1.b of
Appendix R to 10 CFR Part 50 has provided a thorough description of the
proposed change and an adequate safety assessment which address the
issue.
Authorized by Law
This exemption would allow FCS, Unit No. 1, not to provide fire
protection features for structures, systems, and components (SSCs)
important to achieve and maintain cold shutdown or having the
capability of repairing these components within 72 hours (i.e.,
technical requirements of 10 CFR Part 50, Appendix R, Section
III.G.1.b). As stated above, 10 CFR 50.12 allows the NRC to grant
exemptions from the requirements of 10 CFR Part 50. The NRC staff has
determined that granting of the licensee's proposed exemption will not
result in a violation of the Atomic Energy Act of 1954, as amended, or
the Commission's regulations. Therefore, the exemption is authorized by
law.
No Undue Risk to Public Health and Safety
One of the underlying purposes of 10 CFR Part 50, Appendix R,
Section III.G.1.b, is to protect safe shutdown capability. Section
III.G.1.b contains a requirement for performing repairs for maintaining
plant cold shutdown following a fire in any one of certain plant areas.
This is done by ensuring that systems necessary to achieve and maintain
cold shutdown conditions from either the control room or emergency
control stations(s) can be repaired within 72 hours. Based on the
above, no new accident precursors are created by granting exemption for
the 72-hour requirement to provide repair
[[Page 7273]]
procedures and materials for cold shutdown components, thus, the
probability of postulated accidents is not increased. Also based on the
above the consequences of postulated accidents are not increased.
Therefore, there is no undue risk to public health and safety (since
risk is probability x consequences).
Consistent With Common Defense and Security
The proposed exemption would allow FCS, Unit No. 1, to not meet the
requirements of 10 CFR Part 50, Appendix R, Section III.G.1.b for
certain specified areas; thus, procedures and materials for the repair
of redundant cold shutdown components within 72 hours in those areas
would not be needed. This change to the operation of the plant has no
relation to security issues. Therefore, the common defense and security
is not impacted by this exemption.
Special Circumstances
Special circumstances, in accordance with 10 CFR 50.12(a)(2)(ii),
are present whenever application of the regulation in the particular
circumstances is not necessary to achieve the underlying purpose of the
rule. Part of the underlying purpose of 10 CFR Part 50, Appendix R,
Section III.G, is to assure safe shutdown capability. OPPD states that,
in the unlikely event all raw water pumps are lost for any reason, OPPD
maintains an AOP for loss of the raw water system. If all raw water
pumps are lost, due to any condition, the AOP directs the operators to
trip the reactor and enter EOPs based on observed plant condition.
Since these procedures help to assure safe shutdown capability, strict
application of the requirements of 10 CFR Part 50, Appendix R, Section
III.G.1.b, is not necessary to achieve the underlying purpose of the
rule and the special circumstances required by 10 CFR 50.12(a)(2)(ii)
for the granting of an exemption exist.
4.0 Conclusion
Accordingly, the Commission has determined that, pursuant to 10 CFR
50.12(a), the exemption is authorized by law, will not present an undue
risk to the public health and safety, and is consistent with the common
defense and security. Also, special circumstances are present.
Therefore, the Commission hereby grants OPPD an exemption from the
requirements of Section III.G.1.b of 10 CFR Part 50, Appendix R, which
is required by 10 CFR 50.48(b) for plants that were licensed to operate
before January 1, 1979, to FCS, Unit No. 1.
Pursuant to 10 CFR 51.32, the Commission has determined that the
granting of this exemption will not have a significant effect on the
quality of the human environment (73 FR 80441; December 31, 2008).
This exemption is effective upon issuance.
Dated at Rockville, Maryland, this 6th day of February 2009.
For the Nuclear Regulatory Commission.
Joseph G. Giitter,
Director, Division of Operating Reactor Licensing, Office of Nuclear
Reactor Regulation.
[FR Doc. E9-3143 Filed 2-12-09; 8:45 am]
BILLING CODE 7590-01-P