ML082730261
ML082730261 | |
Person / Time | |
---|---|
Site: | Watts Bar |
Issue date: | 10/08/2008 |
From: | Lamb J G Division of Operating Reactor Licensing |
To: | Campbell W R Tennessee Valley Authority |
Lamb John G./NRR/DORL, 415-3100 | |
Shared Package | |
ML082730231 | List: |
References | |
TAC MD7474 | |
Download: ML082730261 (20) | |
Text
October 8, 2008
Mr. William R. Campbell, Jr.
Chief Nuclear Officer and
Executive Vice President Tennessee Valley Authority
6A Lookout Place
1101 Market Street
Chattanooga, TN 37402-2801
SUBJECT:
WATTS BAR NUCLEAR PLANT, UNIT 1 C ISSUANCE OF AMENDMENT REGARDING CONTROL ROOM ENVELOPE HABITABILITY (TAC NO. MD7474)
Dear Mr. Campbell:
The U.S. Nuclear Regulatory Commission (NRC) has issued the enclosed Amendment No. 70
to Facility Operating License No. NPF-90 for Watts Bar Nuclear Plant, Unit 1. This amendment
is in response to your application dated October 26, 2007 (ML073380948).
The amendment revises the Technical Specifications (TS) to adopt TS Task Force (TSTF)
Change Traveler TSTF-448, Revision 3, "Control Room Envelope Habitability." This technical
specification improvement was made avail able by the NRC on January 17, 2007 (72 FR 2022) as part of the consolidated line item improvement process.
A copy of the safety evaluation is also enclosed. Notice of issuance will be included in the
Commission's biweekly Federal Register notice.
Sincerely, /RA/
John G. Lamb, Senior Project Manager Watts Bar Special Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Docket No. 50-390
Enclosures:
- 1. Amendment No. 70 to NPF-90
- 2. Safety Evaluation
cc w/enclosures: See next page
ML082730261 PKG:M L082730231 TS:ML082730277 *via memorandum OFFICE LPWB/PM LPWB/LA ITSB/BC OGC - NLO LPWB/BC NAME JLamb BClayton RElliott* DRoth LRagahavan DATE 09 / 25 /2008 10 / 02 /2008 08/ 22 /2008 10/ 03 /2008 10/8/2008
William R. Campbell, Jr. Tennessee Valley Authority WATTS BAR NUCLEAR PLANT cc: Mr. Gordon P. Arent
New Generation Licensing Manager
Tennessee Valley Authority
5A Lookout Place
1101 Market Street
Chattanooga, TN 37402-2801
Mr. Ashok S. Bhatnagar
Senior Vice President
Nuclear Generation Development
and Construction
Tennessee Valley Authority
6A Lookout Place
1101 Market Street
Chattanooga, TN 37402-2801
Vice President
Nuclear Support
Tennessee Valley Authority
3R Lookout Place
1101 Market Street
Chattanooga, TN 37402-2801
Mr. H. Rick Rogers
Vice President
Nuclear Engineering & Technical Services
Tennessee Valley Authority
3R Lookout Place
1101 Market Street
Chattanooga, TN 37402-2801
General Counsel
Tennessee Valley Authority
6A West Tower
400 West Summit Hill Drive
Knoxville, TN 37902
Mr. John C. Fornicola, Manager
Nuclear Assurance
Tennessee Valley Authority
3R Lookout Place
1101 Market Street
Chattanooga, TN 37402-2801
Mr. Larry E. Nicholson, General Manager
Performance Improvement
Tennessee Valley Authority
3R Lookout Place
1101 Market Street
Chattanooga, TN 37402-2801
Mr. Michael D. Skaggs
Site Vice President
Watts Bar Nuclear Plant
Tennessee Valley Authority
P. O. Box 2000
Spring City, TN 37381 Mr. Michael A. Purcell
Senior Licensing Manager
Nuclear Power Group
Tennessee Valley Authority 4X Blue Ridge
1101 Market Street
Chattanooga, TN 37402-2801
Ms. Beth A. Wetzel, Manager
Corporate Nuclear Licensing and
Industry Affairs
Tennessee Valley Authority 4X Blue Ridge
1101 Market Street
Chattanooga, TN 37402-2801
Mr. Masoud Bajestani, Vice President
Watts Bar Unit 2
Watts Bar Nuclear Plant
Tennessee Valley Authority
P.O. Box 2000
Spring City, TN 37381
Mr. Michael K. Brandon, Manager
Licensing and Industry Affairs
Watts Bar Nuclear Plant
Tennessee Valley Authority
P.O. Box 2000
Spring City, TN 37381
Mr. Michael J. Lorek, Plant Manager
Watts Bar Nuclear Plant
Tennessee Valley Authority
P.O. Box 2000
Spring City, TN 37381
Senior Resident Inspector
Watts Bar Nuclear Plant
U.S. Nuclear Regulatory Commission
1260 Nuclear Plant Road
Spring City, TN 37381
County Executive
375 Church Street Suite 215 Dayton, TN 37321
County Mayor
P. O. Box 156
Decatur, TN 37322 Mr. Lawrence E. Nanney, Director
Division of Radiological Health
Dept. of Environment & Conservation
Third Floor, L and C Annex
401 Church Street
Nashville, TN 37243-1532
TENNESSEE VALLEY AUTHORITY DOCKET NO. 50-390 WATTS BAR NUCLEAR PLANT, UNIT 1 AMENDMENT TO FACILITY OPERATING LICENSE
Amendment No. 70 License No. NPF-90
- 1. The Nuclear Regulatory Commission (the Commission) has found that:
A. The application for amendment by Tennessee Valley Authority (the licensee) dated October 26, 2007, complies with the standards and requirements of the
Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules
and regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the
public, and (ii) that such activities will be conducted in compliance with the
Commission's regulations; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.
2 2. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Facility
Operating License No. NPF-90 is hereby amended to read as follows:
(2) Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendices A and B, as revised
through Amendment No. 70, and the Environmental Protection Plan contained in
Appendix B, both of which are attached hereto, are hereby incorporated into this
license. TVA shall operate the facility in accordance with the Technical
Specifications and the Environmental Protection Plan.
- 3. This license amendment is effective as of the date of its issuance, and shall be implemented no later than 60 days from the date of its issuance.
FOR THE NUCLEAR REGULATORY COMMISSION
/RA/ L. Raghavan, Chief Watts Bar Special Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Operating License and
Technical Specifications
Date of Issuance: October 8, 2008
ATTACHMENT TO AMENDMENT NO. 70 FACILITY OPERATING LICENSE NO. NPF-90 DOCKET NO. 50-390
Replace Page 3 of Operating License NPF-90 with the attached Page 3.
Replace the following pages of the Appendix A Technical Specifications with the attached
pages. The revised pages are identified by amendment number and contain vertical lines
indicating the area of change.
Remove Pages Insert Pages
3.7-22 3.7-22 3.7-23 3.7-23 3.7-24 3.7-24 5.0-25 5.0-25 - 5.0-25a
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 70 TO FACILITY OPERATING LICENSE NO. NPF-90 TENNESSEE VALLEY AUTHORITY WATTS BAR NUCLEAR PLANT, UNIT 1 DOCKET NO. 50-390
1.0 INTRODUCTION
By letter dated October 26, 2007 (ML073380948), the Tennessee Valley Authority (TVA or the
licensee), submitted a request for changes to the Watts Bar Nuclear Plant (WBN), Unit 1, Technical Specifications (TSs). The requested changes would modify TS requirements related
to control room envelope habitability in accordance with Technical Specifications Task Force (TSTF) Revision 3, "Control Room Envelope Habitability." The staff's proposed no significant
hazards consideration determination was published in the Federal Register on August 29, 2008 (73 FR 51014).
On August 8, 2006, the commercial nuclear electrical power generation industry owners group
TSTF submitted a proposed change, TSTF-448, Revision 3, to the improved standard technical
specifications (STSs) (NUREGs 1430-1434) on behalf of the industry (TSTF-448, Revisions 0, 1, and 2 were prior draft iterations). TSTF-448, Revision 3, is a proposal to establish effective
and appropriate action, surveillance, and administrative STS requirements related to ensuring
the habitability of the control room envelope (CRE).
In NRC Generic Letter (GL) 2003-01,"Control Room Habitability," dated June 12, 2003 (ML031620248), licensees were alerted to findings at facilities that existing TS surveillance
requirements (SRs) for the Control Room En velope Emergency Ventilation System (CREEVS) may not be adequate. Specifically, the results of American Society for Testing and Materials (ASTM) E741, "Standard Test Method for Determining Air Change in a Single Zone by Means of
a Tracer Gas Dilution," 2000, tracer gas tests to measure CRE unfiltered inleakage at facilities
indicated that the differential pressure surveillance is not a reliable method for demonstrating
CRE boundary operability. Licensees were requested to address existing TS as follows:
Provide confirmation that your technical specifications verify the integrity [i.e.,
operability] of the CRE [boundary], and the assumed [unfiltered] inleakage rates
of potentially contaminated air. If you currently have a differential pressure surveillance requirement to demonstrate CRE [boundary] integrity, provide the
basis for your conclusion that it remains adequate to demonstrate CRE integrity
in light of the ASTM E741 testing results. If you conclude that your differential
pressure surveillance requirement is no longer adequate, provide a schedule for:
- 1) revising the surveillance requirement in your technical specification to
reference an acceptable surveillance methodology (e.g., ASTM E741), and
- 2) making any necessary modifications to your CRE boundary so that
compliance with your new surveillance requirement can be demonstrated.
If your facility does not currently have a technical specification surveillance requirement for your CRE integrity, explain how and at what frequency you
confirm your CRE integrity and why this is adequate to demonstrate CRE integrity.
To promote standardization and to minimize the resources that would be needed to create and
process plant-specific amendment applications in response to the concerns described in the
GL, the industry and the NRC proposed revisions to CRE habitability system requirements
contained in the STSs, using the STS change traveler process. This effort culminated in
Revision 3 to traveler TSTF 448, "Control Room Habitability," which the U.S. Nuclear Regulatory
Commission (NRC) staff approved on January 17, 2007.
Consistent with the traveler as incorporated into NUREG 1431, the licensee proposed revising
action and SRs in Specification 3.7.10, "C ontrol Room Emergency Ventilation System (CREVS)," and adding a new administrative controls program, Specification 5.2.7.20, "Control Room Envelope Habitability Program." The purpose of the changes is to ensure that CRE
boundary operability is maintained and verified through effective surveillance and programmatic
requirements, and that appropriate remedial actions are taken in the event of an inoperable
CRE boundary.
Some editorial and plant-specific changes were incorporated into this safety evaluation resulting
in minor deviations from the model safety evaluation text in TSTF-448, Revision 3.
2.0 REGULATORY EVALUATION
2.1 Control
Room and Control Room Envelope NRC Regulatory Guide 1.196, "Control Room Habitability at Light-water Nuclear Power
Reactors," Revision 0, May 2003 (ML031490611), uses the term "control room envelope" in
addition to the term "control room" and defines each term as follows:
Control Room: The plant area, defined in the facility licensing basis, in which actions can be taken to operate the plant safely under normal conditions and to maintain the reactor in a safe condition during accident situations. It encompasses the instrumentation and controls necessary for a safe shutdown of the plant and typically includes the critical document reference file, computer room (if used as an integral part of the emergency response plan), shift supervisor's office, operator wash room and kitchen, and other critical areas to which frequent personnel access or continuous occupancy may be necessary in
the event of an accident.
Control Room Envelope: The plant area, defined in the facility licensing basis, that in the event of an emergency, can be isolated from the plant areas and the environment external to the CRE. This area is served by an emergency ventilation system, with the intent of maintaining the habitability of the control room. This area encompasses the control room, and may encompass other
non-critical areas to which frequent personnel access or continuous occupancy is
not necessary in the event of an accident.
NRC Regulatory Guide 1.197, "Demonstrating Control Room Envelope Integrity at Nuclear
Power Reactors," Revision 0, May 2003 (ML031490664), also contains these definitions, but
uses the term CRE to mean both. This is because the protected environment provided for operators varies with the nuclear power facility. At some facilities this environment is limited to the control room; at others, it is the CRE. In this safety evaluation, consistent with the proposed
changes to the STSs, the CRE will be used to designate both environments as defined above.
For consistency, facilities should use the term CRE with an appropriate facility-specific definition
derived from the above CRE definition.
2.2 Control
Room Emergency Ventilation System (CREVS)
The CREVS (the term used at WBN, Unit 1 for the CREEVS provides a protected environment
from which operators can control the unit, during airborne challenges from radioactivity, hazardous chemicals, and fire byproducts, such as fire-suppression agents and smoke, during
both normal and accident conditions.
The CREVS is designed to maintain a habitable environment in the CRE for 30 days of
continuous occupancy after a Design Basis Accident (DBA) without exceeding a 5 rem total
effective dose equivalent (TEDE).
The CREVS consists of two independent, redundant trains, each capable of maintaining the
habitability of the CRE. Each CREVS train is considered operable when the individual
components necessary to limit CRE occupant exposure are operable. A CREVS train is
considered operable when the associated:
$ Fan is operable;
$ High efficiency particulate air (HEPA) filters and charcoal adsorbers are not excessively restricting flow, and are capable of performing their filtration
functions;
$ Ductwork, valves, and dampers are operable, and air circulation can be maintained; and
$ CRE boundary is operable (the single boundary supports both trains).
The CRE boundary is considered operable when the measured unfiltered air inleakage is less
than or equal to the inleakage value assumed by the licensing basis analyses of design basis
accident consequences to CRE occupants.
2.3 Regulations
Applicable to Control Room Habitability In Appendix A, "General Design Criteria for Nuclear Power Plants," to 10 CFR Part 50, "Domestic Licensing of Production and Utilization Facilities," General Design Criteria (GDC) 1, 2, 3, 4, 5, and 19 apply to CRE habitability. A summary of these GDCs follows.
GDC 1, "Quality Standards and Records," requires that structures, systems, and components (SSCs) important to safety be designed, fabricated, erected, and tested to quality standards
commensurate with the importance of the safety functions performed.
GDC 2, A Design Basis for Protection Against Natural Phenomena,@ requires that SSCs important to safety be designed to withstand the effects of earthquakes and other natural hazards.
GDC 3, "Fire Protection," requires SSCs important to safety be designed and located to
minimize the effects of fires and explosions.
GDC 4, "Environmental and Dynamic Effects Desi gn Bases," requires SSCs important to safety to be designed to accommodate the effects of and to be compatible with the environmental
conditions associated with normal operation, maintenance, testing, and postulated accidents, including loss-of-coolant accidents (LOCAs).
GDC 5, "Sharing of Structures, Systems, and Components," requires that SSCs important to safety not be shared among nuclear power units unless it can be shown that such sharing will
not significantly impair their ability to perform their safety functions, including, in the event of an
accident in one unit, the orderly shutdown and cooldown of the remaining units.
GDC 19, "Control Room," requires that a contro l room be provided from which actions can be taken to operate the nuclear reactor safely under normal conditions and to maintain the reactor
in a safe condition under accident conditions, including a LOCA. Adequate radiation protection
is to be provided to permit access and occupancy of the control room under accident conditions
without personnel receiving radiation exposures in excess of specified values.
Prior to incorporation of TSTF-448, Revision 3, the STS requirements addressing CRE
boundary operability resided only in the following CRE ventilation system specifications:
$ NUREG-1431, TS 3.7.10, "Control Room Emergency Filtration System (CREFS)."
In these specifications, the SR associated with demonstrating the operability of the CRE
boundary requires verifying that one CREEVS train can maintain a positive pressure relative to
the areas adjacent to the CRE during the pressurization mode of operation at a makeup flow
rate. Facilities that pressurize the CRE during the emergency mode of operation of the
CREEVS have similar SRs. Regardless, the results of ASTM E741 tracer gas tests to measure
CRE unfiltered inleakage at facilities indicated that the differential pressure surveillance is not a
reliable method for demonstrating CRE boundary operability. That is, licensees were able to
obtain differential pressure and flow meas urements satisfying the SR limits even though unfiltered inleakage was determined to exceed the value assumed in the safety analyses.
In addition to an inadequate SR, the action requirements of these specifications were
ambiguous regarding CRE boundary operability in the event CRE unfiltered inleakage is found
to exceed the analysis assumption. The ambiguity stemmed from the view that the CRE
boundary may be considered operable but degraded in this condition, and that it would be
deemed inoperable only if calculated radiological exposure limits for CRE occupants exceeded
a licensing basis limit (e.g., as stated in GDC-
- 19) even while crediting compensatory measures.
NRC Administrative Letter (AL) 98-10, "Dispositioning of Technical Specifications That Are
Insufficient to Assure Plant Safety," (AL 98-10) states that "the discovery of an improper or
inadequate TS value or required action is considered a degraded or nonconforming condition,"
which is defined in NRC Inspection Manual Chapter 9900; see latest guidance in Regulatory
Issue Summary (RIS) 2005-20 (ML073440103).
A Imposing administrative controls in response to an improper or inadequate TS is considered an acceptable short-term corrective action. The NRC staff expects that, following the imposition of administrative controls, an amendment to the inadequate TS, with appropriate justification and schedule, will be submitted in a timely fashion."
Licensees that have found unfiltered inleakage in excess of the limit assumed in the safety analyses and have yet to either reduce the inleakage below the limit or establish a higher
bounding limit through re-analysis, have implem ented compensatory actions to ensure the safety of CRE occupants, pending final resolution of the condition, consistent with RIS 2005-20.
However, based on GL 2003-01 and AL 98-10, the NRC staff expects each licensee to propose
TS changes that include a surveillance to periodically measure CRE unfiltered inleakage in
order to satisfy 10 CFR 50.36(d)(3), which requires a facility's TS to include SRs, which it
defines as "requirements relating to test, calibration, or inspection to assure that the necessary
quality of systems and components is maintained, that facility operation will be within safety
limits, and that limiting conditions for operation will be met
." (Emphasis added.)
The NRC staff also expects facilities to propose unambiguous remedial actions, consistent with
10 CFR 50.36(d)(2), for the condition of not meeting the limiting condition for operation (LCO)
due to an inoperable CRE boundary. The action requirements should specify a reasonable
completion time to restore conformance to the LCO before requiring a facility to be shut down.
This completion time should be based on the benefits of implementing mitigating actions to
ensure CRE occupant safety and sufficient time to resolve most problems anticipated with the
CRE boundary, while minimizing the chance that operators in the CRE will need to use
mitigating actions during accident conditions.
2.4 Adoption
of TSTF-448 Revision 3 Adoption of TSTF-448, Revision 3, will assure that a facility's TS LCO for the CREVS is met by
demonstrating unfiltered leakage into the CRE is within limits (i.e., the operability of the CRE
boundary). In support of this surveillance, which specifies a test interval (frequency) described
in Regulatory Guide 1.197, TSTF-448 also adds TS administrative controls to assure the
habitability of the CRE between performances of the ASTM E741 test. In addition, adoption of
TSTF-448 will establish clearly stated and reasonable required actions in the event CRE
unfiltered inleakage is found to exceed the analysis assumption.
The changes made by TSTF-448 to the STS requirements for the CREVS and the CRE
boundary conform to 10 CFR 50.36(d)(2) and 10 CFR 50.36(d)(3). Their adoption will assure
that a plant's CRE will remain habitable during normal operation and DBA conditions. The staff
has, therefore, concluded that these changes are acceptable for adoption by licensees.
3.0 TECHNICAL EVALUATION
The NRC staff reviewed the proposed changes against the corresponding changes made to the
STSs by TSTF-448, Revision 3, which the NRC staff has found to satisfy applicable regulatory
requirements, as described above in Section 2.0. The emergency operational mode of the
CREVS at the WBN, Unit 1 pressurizes the CRE to minimize unfiltered air inleakage. The
proposed changes are consistent with this design.
3.1 Proposed
Changes The proposed amendment would strengthen CRE habitability TS requirements by changing
TS 3.7.10, "Control Room Emergency Ventilati on System" and adding a new TS administrative controls program on CRE habitability. Accompanying the proposed TS changes are appropriate
conforming technical changes to the TS Bases. The proposed revision to the Bases also
includes editorial and administrative changes to reflect applicable changes to the corresponding
STS Bases, which were made to improve clarity, conform with the latest information and
references, correct factual errors, and achi eve more consistency among the STS NUREGs.
Except for plant-specific differences, all of thes e changes are consistent with STSs as revised by TSTF-448, Revision 3. The NRC staff compared the proposed TS changes to the STSs and the STS markups and evaluations in TSTF-448. The staff verified that differences from the
STSs were adequately justified on the basis of plant-specific design or retention of current
licensing basis. The NRC staff also reviewed the proposed changes to the TS Bases for
consistency with the STS Bases and the plant-specific design and licensing bases, although
approval of the Bases is not a condition for accepting the proposed amendment. However, TS 5.6, "Technical Specifications Bases Control Program," provides assurance that the licensee
has established and will maintain the adequacy of the Bases. The proposed Bases for TS 3.7.10 refer to specific guidance in Nuclear Energy Institute document NEI 99-03, "Control
Room Habitability Assessment Guidance," Revision 0, dated June 2001, which the NRC staff
has formally endorsed, with exceptions, through Regulatory Guide 1.196, A Control Room Habitability at Light-Water Nuclear Power Reactors,@ dated May 2003 (ML031490611).
3.2 Editorial
Changes
The licensee proposed editorial changes to TS 3.7.10, "Control Room Emergency Ventilation
System," to establish standard terminology, such as "control room envelope (CRE)" in place of "control room," except for the plant-specific name for the CREEVS (CREVS), and "radiological, chemical, and smoke hazards" in place of various phrases to describe the hazards that CRE
occupants are protected from by the CREVS. These changes improve the usability and quality
of the presentation of the TS, have no adverse impact on safety, and therefore, are acceptable.
3.3 TS 3.7.10, "Control Room Emergency Ventilation System"
The licensee proposed to revise the action requirements of TS 3.7.10, "Control Room
Emergency Ventilation System," to acknowledge that an inoperable CRE boundary, depending
upon the location of the associated degradation, could cause just one, instead of both CREVS
trains to be inoperable. This is accomplished by revising Condition A to exclude Condition B, and revising Condition B to address one or more CREVS trains, as follows:
o Condition A One required CREVS train inoperable for reasons other than Condition B.
o Condition B One or more CREVS trains inoperable due to inoperable CRE boundary in MODE 1, 2, 3, or 4.
This change clarifies how to apply the action requirements in the event just one CREVS train is
unable to ensure CRE occupant safety within licensing basis limits because of an inoperable
CRE boundary. It enhances the usability of Conditions A and B with a presentation that is more
consistent with the intent of the existing requirements. This change is an administrative change
because it neither reduces nor increases the existing action requirements, and, therefore, is
acceptable.
New Required Action B.1 requires the licensee to immediately initiate action to implement
mitigating actions. New Required Action B.2 requires the licensee to verify, within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, that
in the event of a DBA, CRE occupant radiological exposures will not exceed the calculated dose
of the licensing basis analyses of DBA cons equences, CRE occupant exposure to chemical hazards will not exceed limits, and that CRE o ccupants are protected from smoke hazards. New Required Action B.3 requires the licensee to restore CRE boundary to operable status within
90 days.
The 24-hour Completion Time of new Required Action B.2 is reasonable based on the low probability of a DBA occurring during this time period, and the use of mitigating actions as
directed by Required Action B.1. The 90-day Completion Time of new Required Action B.3 is
reasonable based on the determination that the mitigating actions will ensure protection of CRE
occupants within analyzed limits while limiting the probability that CRE occupants will have to
implement protective measures that may adversely affect their ability to control the reactor and
maintain it in a safe shutdown condition in the event of a DBA. The 90-day Completion Time is
a reasonable time to diagnose, plan and possibly repair, and test most anticipated problems
with the CRE boundary. Therefore, proposed Actions B.1, B.2, and B.3 are acceptable.
To distinguish new Condition B from the existing condition for two CREVS trains inoperable, Condition F (renumbered as Condition G), is revised to state, "Two CREVS trains inoperable
during MODE 1, 2, 3, or 4 for reasons other than Condition B or E." The changes to existing
Condition F are less restrictive because these Conditions will no longer apply in the event one
or two CREVS trains are inoperable due to an inoperable CRE boundary during unit operation in
Mode 1, 2, 3, or 4. This is acceptable because the new Action B establishes adequate remedial
measures in this condition. With the addition of a new Condition B, existing Condition B, C, D, E, and F are re-designated C, D, E, F, and G, respectively.
The licensee also proposed to modify the CREVS LCO by adding a NOTE allowing the CRE
boundary to be opened intermittently under administrative controls. As stated in the LCO
Bases, this NOTE only applies to openings in the CRE boundary that can be rapidly restored to
the design condition, such as doors, hatches, floor plugs, and access panels. For entry and exit
through doors, the administrative controls of t he opening is performed by the person(s) entering or exiting the area. For other openings, these controls should be proceduralized and consist of
stationing a dedicated individual at the opening who is in continuous communication with
operators in the CRE. This individual will have a method to rapidly close the opening and to
restore the CRE boundary to a condition equivalent to the design condition when a need for
CRE isolation is indicated." The allowance of this NOTE is acceptable because the
administrative controls will ensure that the opening will be quickly sealed to maintain the validity
of the licensing basis analyses of DBA consequences.
The licensee proposed to add a new condition to Action E (renumbered as Condition F) of
TS 3.7.10 that states, "One or more CREVS trains inoperable due to an inoperable CRE
boundary in Mode 5 or 6, or during movement of irradiated fuel assemblies." The specified
Required Action proposed for this condition is the same as for the existing condition of Action E, which states, "Two CREVS trains inoperable in MODE 5 or 6, or during movement of irradiated
fuel assemblies." Accordingly, the new condition is stated with the other condition in Action E
using the logical connector "OR
". The practical result of this presentation in format is the same as specifying two separately numbered Actions, one for each condition. Its advantage is to make the TS Actions table easier to use by avoiding having an additional numbered row in the
Actions table. The new condition in Action E is needed because proposed Action B will only
apply in Modes 1, 2, 3, and 4. As such, this change will ensure that the Actions table continues
to specify a condition for an inoperable CRE boundary during Modes 5 and 6 and during
refueling. Therefore, this change is administrative and acceptable.
In the emergency mode of operation, the CREVS isolates unfiltered ventilation air supply
intakes, filters the emergency ventilation air supply to the CRE, and pressurizes the CRE to
minimize unfiltered air inleakage past the CRE boundary. The licensee proposed to delete the
CRE pressurization SR. This SR requires verifying that one CREVS train, operating in the
emergency mode, can maintain a pressure of 0.125 inches water gauge, relative to the outside atmosphere and adjacent areas during the pressurization mode of operation at a makeup flow rate of 711cfm and a recirculation flow rate 2960 and 3618 cfm. The deletion of this SR is proposed because measurements of unfiltered air leakage into the CRE at numerous reactor facilities demonstrated that a basic assumption of this SR, an essentially leak-tight CRE
boundary, was incorrect for most facilities. Hence, meeting this SR by achieving the required
CRE pressure is not necessarily a conclusive indication of CRE boundary leak tightness (i.e., CRE boundary operability). In its response to GL 2003-01, the licensee reported in a letter
dated August 4, 2004 (ML042230173) that it had determined the WBN CRE pressurization
surveillance, SR 3.7.10.4, was not adequate to demonstrate the operability of the CRE
boundary, and proposed to replace it with an inleakage measurement SR and a CRE
Habitability Program in TS Section 5.2.7.20, in accordance with the approved version of
TSTF-448. Based on the adoption of TSTF-448, Revision 3, the licensee's proposal to delete
SR 3.7.10.4 is acceptable.
The proposed CRE inleakage measurement SR states, "Perform required CRE unfiltered air
inleakage testing in accordance with the Control Room Habitability Program." The CRE
Habitability Program TS, proposed TS 5.2.7.20, requires that the program include
"Requirements for determining the unfiltered air inleakage past the CRE boundary into the CRE
in accordance with the testing methods and at the frequencies specified in Sections C.1 and C.2
of Regulatory Guide 1.197, Revision 0 (ML031490664). This guidance references ASTM E741
as an acceptable method for ascertaining the unfiltered leakage into the CRE. The licensee has
proposed to follow this method. Therefore, the proposed CRE inleakage measurement SR is
acceptable.
3.4 TS 5.5.14, "Control Room Envelope Habitability Program"
The proposed administrative controls program TS is consistent with the model program TS in TSTF-448, Revision 3. In combination with SR 3.7.10.4, this program is intended to ensure the
operability of the CRE boundary, which as part of an operable CREVS will ensure that CRE
habitability is maintained such that CRE occupants can control the reactor safely under normal
conditions and maintain it in a safe condition following a radiological event, hazardous chemical
release, or a smoke challenge. The program shall ensure that adequate radiation protection is
provided to permit access and occupancy of the CRE under DBA conditions without personnel
receiving radiation exposures in excess of 5 rem TEDE for the duration of the accident.
A CRE Habitability Program TS acceptable to the NRC staff requires the program to contain the
following elements:
Definitions of CRE and CRE boundary.
This element is intended to ensure that these definitions accurately describe the plant
areas that are within the CRE, and also the interfaces that form the CRE boundary, and
are consistent with the general definitions discussed in Section 2.1 of this safety
evaluation. Establishing what is meant by the CRE and the CRE boundary will preclude
ambiguity in the implementation of the program.
Configuration control and preventive maintenance of the CRE boundary.
This element is intended to ensure the CRE boundary is maintained in its design condition. Guidance for implementing this element is contained in Regulatory
Guide 1.196, which endorsed, with exceptions, NEI 99-03, Rev. 0. Maintaining the CRE boundary in its design condition provides assurance that its leak-tightness will not significantly degrade between CRE inleakage determinations. Assessment of CRE habitability at the frequencies stated in Sections C.1 and C.2 of Regulatory Guide 1.197, Revision 0, and measurement of unfiltered air leakage into the CRE in accordance with the testing methods and at the frequencies stated in Sections C.1 and C.2 of Regulatory
Guide 1.197.
This element is intended to ensure that the plant assesses CRE habitability consistent
with Sections C.1 and C.2 of Regulatory Guide 1.197. Assessing CRE habitability at the
NRC accepted frequencies provides assurance that significant degradation of the CRE
boundary will not go undetected between CRE inleakage determinations. Determination
of CRE inleakage using test methods acceptable to the NRC staff assures that test
results are reliable for ascertaining CRE boundary operability. Determination of CRE
inleakage at the NRC accepted frequencies provides assurance that significant
degradation of the CRE boundary will not occur between CRE inleakage determinations.
Measurement of CRE pressure with respect to all areas adjacent to the CRE boundary at designated locations for use in assessing the CRE boundary at a frequency of 18 months on a
staggered test basis (with respect to the CREVS trains).
This element is intended to ensure that CRE differential pressure is regularly measured
to identify changes in pressure warranting evaluation of the condition of the CRE
boundary. Obtaining and trending pressure data provides additional assurance that
significant degradation of the CRE boundary will not go undetected between CRE
inleakage determinations.
Quantitative limits on unfiltered inleakage.
This element is intended to establish the CRE inleakage limit as the CRE unfiltered
infiltration rate assumed in the CRE occupant radiological consequence analyses of
design basis accidents. Having an unambiguous criterion for the CRE boundary to be
considered operable in order to meet LCO 3.7.10 will ensure that associated action
requirements will be consistently applied in the event of CRE degradation resulting in
inleakage exceeding the limit.
Consistent with TSTF-448, Revision 3, the program states that the provisions of SR 3.0.2 are applicable to the program frequencies for performing the activities required by program paragraph number c, parts (i) and (ii) (assessment of CRE habitability and measurement of CRE inleakage), and paragraph d (measurement of CRE differential pressure).
This statement is needed to avoid confusion. SR 3.0.2 is applicable to the surveillance
that references the testing in the CRE Habitability Program. However, SR 3.0.2 is not
applicable to Administrative Controls unless specifically invoked. Providing this
statement in the program eliminates any confusion regarding whether SR 3.0.2 is applicable, and is acceptable. Consistent with TSTF-448, Revision 3, proposed TS 5.5.14 states that (1) a CRE Habitability Program shall be established and implemented, (2) the program shall include all of the NRC-staff required elements, as described above, and (3) the provisions of SR 3.0.2 shall apply to program frequencies. Therefore, TS 5.5.14, which is consistent with the model program TS approved by the NRC staff in
TSTF-448, Revision 3, is acceptable.
3.5 Implementation
of New Surveillance and Assessment Requirements by the Licensee
The licensee has proposed license conditions regarding the initial performance of the new
surveillance and assessment requirements. The new license conditions adopted the conditions
in section 2.3 of the model application published in the Federal Register on January 17, 2007 (72 FR 2022). Plant specific changes were made to these proposed license conditions. The
proposed plant specific license conditions are c onsistent with the model application, and are acceptable.
3.6 Adoption
of TSTF-448 Revision 3 by the WBN, Unit 1 The changes made by TSTF-448 to the STS requirements for the CREVS and the CRE
boundary conform to 10 CFR 50.36(d)(2) and 10 CFR 50.36(d)(3). The proposed plant-specific
adoption of the changes also conform to regulatory requirements of 10 CFR 50.36(d)(2) and
10 CFR 50.36(d)(3) and will better assure that the WBN's CRE will remain habitable during
normal operation and design basis accident conditions. The staff has therefore concluded that
these changes are acceptable for adoption by WBN, Unit 1.
4.0 STATE CONSULTATION
In accordance with the Commission
=s regulations, the Tennessee state official was notified of the proposed issuance of the amendment.
The State official had no comments.
5.0 ENVIRONMENTAL CONSIDERATION
The amendment changes a requirement with respect to the installation or use of a facility
component located within the restricted area as defined in 10 CFR Part 20 and changes
surveillance requirements. The NRC staff has determined that the amendment involves no
significant increase in the amounts and no significant change in the types of any effluents that
may be released offsite, and that there is no significant increase in individual or cumulative
occupational radiation exposure. The Commission has previously issued a proposed finding
that the amendment involves no-significant-hazards considerations, and there has been no
public comment on the finding Federal Register dated August 29, 2008 (73 FR 51014).
Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in
10 CFR 51.22(c)(9) and (c)(10). Pursuant to 10 CFR 51.22(b), no environmental impact
statement or environmental assessment need be prepared in connection with the issuance of
the amendment.
6.0 FINAL NO SIGNIFICANT HAZARDS CONSIDERATION
DETERMINATION
6.1 Background
The Commission issued a "Notice of Consideration of Issuance of Amendment to Facility
Operating License, Proposed No Significant Hazards Consideration Determination and
Opportunity for a Hearing" for the proposed amendment in the Federal Register on August 29, 2008 (73 FR 51014). This Notice provided 60 days for the public to request a
hearing.
The Commission's regulations in 10 CFR 50.91(a)(2)(i) state that:
The Commission may publish in the Federal Register under §2.105 an individual notice of proposed action for an amendment for which it makes a proposed
determination that no significant hazards consideration is involved . . . .
Pursuant to 10 CFR 50.91(a)(2)(ii), the notice will contain the staff's proposed 10 CFR 50.92
determination, provide a brief description of the amendment and the facility involved, solicit
public comments thereon, and provide for a 30-day comment period. The Commission issued a
"Notice of Consideration of Issuance of Amendment to Facility Operating License, Proposed No
Significant Hazards Consideration Determination and Opportunity for a Hearing" for the
proposed amendment in the Federal Register on August 29, 2008 (73 FR 51014). There were no comments received.
Pursuant to 10 CFR 50.91(a)(3), the Commission does not publish a final determination on no
significant hazards consideration, unless it receives a request for a hearing.
The Commission's regulations in 10 CFR 50.91(a)(4) state that:
Where the Commission makes a final determination that no significant hazards
consideration is involved and that the amendment should be issued, the
amendment will be effective on issuance, even if adverse public comments have been received and even if an interested person meeting the provisions for
intervention called for in §2.309 of this chapter has filed a request for a hearing.
The Commission need hold any required hearing only after it issues an
amendment, unless it determines that a significant hazards consideration is
involved, in which case the Commission will provide an opportunity for a prior
hearing.
The Commission's regulations in 10 CFR 50.92(c) state that the Commission may make a final
determination that a proposed license amendment involves no significant hazards consideration (NSHC) if the operation of the facility in accordance with the proposed amendment would not:
(1) Involve a significant increase in the probability or consequences of an
accident previously evaluated; or (2) Create the possibility of a new or different
kind of accident from any accident prev iously evaluated; or (3) Involve a significant reduction in a margin of safety.
Pursuant to 10 CFR 50.91, the NRC staff made a proposed determination that the WBN, Unit 1
amendment request involves NSHC. A "Notice of Consideration of Issuance of Amendment to Facility Operating License, Proposed No Significant Hazards Consideration Determination and
Opportunity for a Hearing" was issued in the Federal Register on August 29, 2008 (73 FR 51014). The notice provided a 30-day opportunity for public comment. The NRC staff did
not receive comments on the proposed NSHC determination.
6.2 Final
NSHC Determination
The NRC staff has completed its evaluation of the licensee's proposed amendment as
discussed above. Based on its evaluation, the staff has made a final determination that the
proposed amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated; does not create the possibility of a new or different kind of accident from any accident previously evaluated; and does not involve a significant reduction in a margin of safety. The following evaluation in relation to the three standards of 10 CFR
50.92(c) explains the staff's final NSHC determination.
6.3 First
Standard
Does the proposed amendment involve a significant increase in the probability or consequences
of an accident previously evaluated?
Response: No
The proposed change does not adversely affect accident initiators or precursors nor alter the
design assumptions, conditions, or configuration of the facility. The proposed change does not
alter or prevent the ability of SSCs to perform their intended function to mitigate the
consequences of an initiating event within the assumed acceptance limits. The proposed
change revises the TS for the CRE emergency vent ilation system, which is a mitigation system designed to minimize unfiltered air leakage into the CRE and to filter the CRE atmosphere to
protect the CRE occupants in the event of accidents previously analyzed. An important part of
the CRE emergency ventilation system is t he CRE boundary. The CRE emergency ventilation system is not an initiator or precursor to any accident previously evaluated. Therefore, the probability of any accident previously evaluated is not increased. Performing tests to verify the operability of the CRE boundary and implementing a program to assess and maintain CRE
habitability ensure that the CRE emergency ventilation system is capable of adequately
mitigating radiological consequences to CRE occupants during accident conditions, and that the
CRE emergency ventilation system will perform as assumed in the consequence analyses of design basis accidents. Thus, the consequences of any accident previously evaluated are not
increased. Therefore, the proposed change does not involve a significant increase in the
probability or consequences of an accident previously evaluated.
6.4 Second
Standard
Does the proposed amendment create the possibility of a new or different kind of accident from
any accident previously evaluated?
Response: No
The proposed change does not impact the accident analysis. The proposed change does not
alter the required mitigation capability of the CRE emergency ventilation system, or its
functioning during accident conditions as assumed in the licensing basis analyses of design
basis accident radiological consequences to CRE occupants. No new or different accidents
result from performing the new surveillanc e or following the new program. The proposed change does not involve a physical alteration of the plant (i.e
., no new or different type of equipment will be installed) or a significant change in the methods governing normal plant
operation. The proposed change does not alter any safety analysis assumptions and is
consistent with current plant operating practice. Therefore, this change does not create the
possibility of a new or different kind of acci dent from any accident previously evaluated.
6.5 Third
Standard
Does the proposed amendment involve a significant reduction in a margin of safety?
Response: No
The proposed change does not alter the manner in whic h safety limits, limit ing safety system settings or limiting conditions for operation as determined. The proposed change does not
affect safety analysis acceptance criteria. The proposed change will not result in plant
operation in a configuration outside the design basis for an unacceptable period of time without
compensatory measures. The proposed change does not adversely affect systems that respond to safely shut down the plant and to maintain the plant in a safe shutdown condition.
Therefore, the proposed change does not involve a significant reduction in a margin of safety.
6.6 Conclusion
On the basis of the above evaluation, the NRC staff has made a final determination that the
proposed amendment does not involve a significant hazards consideration.
7.0 CONCLUSION
The Commission has concluded, on the basis of the considerations discussed above, that
(1) there is reasonable assurance that the health and safety of the public will not be endangered
by operation in the proposed manner, (2) such activities will be conducted in compliance with
the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the
common defense and security or to the health and safety of the public.
Principal contributor: Matthew E. Hamm
Date: October 8, 2008