ML081220281
ML081220281 | |
Person / Time | |
---|---|
Site: | Cooper |
Issue date: | 05/12/2008 |
From: | Lyon C NRC/NRR/ADRO/DORL/LPLIV |
To: | Minahan S Nebraska Public Power District (NPPD) |
Lyon, C F, NRR/DLPM, 415-2296 | |
Shared Package | |
ML081220273 | List: |
References | |
TAC MD7778 | |
Download: ML081220281 (20) | |
Text
May 12, 2008 Mr. Stewart B. Minahan Vice President-Nuclear and CNO Nebraska Public Power District 72676 648A Avenue Brownville, NE 68321
SUBJECT:
COOPER NUCLEAR STATION - ISSUANCE OF AMENDMENT RE: CONTROL ROOM ENVELOPE HABITABILITY (TAC NO. MD7778)
Dear Mr. Minahan:
The U.S. Nuclear Regulatory Commission (the Commission) has issued the enclosed Amendment No. 230 to Facility Operating License No. DPR-46 for the Cooper Nuclear Station.
The amendment consists of changes to the Technical Specifications (TS) in response to your application dated January 14, 2008.
The amendment revises the TS requirements related to control room envelope habitability in accordance with TS Task Force (TSTF) traveler TSTF-448-A, Control Room Habitability, Revision 3. This TS improvement was made available by the Commission on January 17, 2007 (72 FR 2022) as part of the consolidated line item improvement process (CLIIP).
A copy of our related Safety Evaluation is also enclosed. The Notice of Issuance will be included in the Commission's next biweekly Federal Register notice.
Sincerely,
/RA/
Carl F. Lyon, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-298
Enclosures:
- 1. Amendment No. 230 to DPR-46
- 2. Safety Evaluation cc w/encls: See next page
(s).: Pkg ML081220273, Amdt. ML081220281, License/TS Pgs ML081220289 OFFICE LPL4/PM LPL4/LA SCVB/BC ITSB/BC OGC LPL4/BC NAME FLyon GLappert RDennig* RElliott NOT REQD THiltz DATE 5/6/08 5/6/08 4/22/08 5/12/08 ML073130139 5/12/08 Cooper Nuclear Station (09/2007) cc:
Mr. Ronald D. Asche Mr. H. Floyd Gilzow President and Chief Executive Officer Deputy Director for Policy Nebraska Public Power District Missouri Department of Natural Resources 1414 15th Street P.O. Box 176 Columbus, NE 68601 Jefferson City, MO 65102-0176 Mr. Gene Mace Senior Resident Inspector Nuclear Asset Manager U.S. Nuclear Regulatory Commission Nebraska Public Power District P.O. Box 218 P.O. Box 98 Brownville, NE 68321 Brownville, NE 68321 Regional Administrator, Region IV Mr. John C. McClure U.S. Nuclear Regulatory Commission Vice President and General Counsel 611 Ryan Plaza Drive, Suite 400 Nebraska Public Power District Arlington, TX 76011 P.O. Box 499 Columbus, NE 68602-0499 Director, Missouri State Emergency Management Agency Mr. David Van Der Kamp P.O. Box 116 Licensing Manager Jefferson City, MO 65102-0116 Nebraska Public Power District P.O. Box 98 Chief, Radiation and Asbestos Brownville, NE 68321 Control Section Kansas Department of Health Mr. Michael J. Linder, Director and Environment Nebraska Department of Environmental Bureau of Air and Radiation Quality 1000 SW Jackson P.O. Box 98922 Suite 310 Lincoln, NE 68509-8922 Topeka, KS 66612-1366 Chairman Ms. Melanie Rasmussen Nemaha County Board of Commissioners Radiation Control Program Director Nemaha County Courthouse Bureau of Radiological Health 1824 N Street Iowa Department of Public Health Auburn, NE 68305 Lucas State Office Building, 5th Floor 321 East 12th Street Ms. Julia Schmitt, Manager Des Moines, IA 50319 Radiation Control Program Nebraska Health & Human Services R & L Mr. Keith G. Henke, Planner Public Health Assurance Division of Community and Public Health 301 Centennial Mall, South Office of Emergency Coordination P.O. Box 95007 930 Wildwood P.O. Box 570 Lincoln, NE 68509-5007 Jefferson City, MO 65102
Mr. Paul V. Fleming, Director of Nuclear Safety Assurance Nebraska Public Power District P.O. Box 98 Brownville, NE 68321 Mr. John F. McCann, Director Licensing, Entergy Nuclear Northeast Entergy Nuclear Operations, Inc.
440 Hamilton Avenue White Plains, NY 10601-1813
NEBRASKA PUBLIC POWER DISTRICT DOCKET NO. 50-298 COOPER NUCLEAR STATION AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 230 License No. DPR-46
- 1. The U.S. Nuclear Regulatory Commission (the Commission) has found that:
A. The application for amendment by Nebraska Public Power District (the licensee),
dated January 14, 2008, 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 license 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. 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. DPR-46 is hereby amended to read as follows:
(2) Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No. 230, are hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specifications.
- 3. The license amendment is effective as of its date of issuance and shall be implemented within 180 days from the date of issuance.
FOR THE NUCLEAR REGULATORY COMMISSION
/RA/
Thomas G. Hiltz, Chief Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Facility Operating License No. DPR-46 and Technical Specifications Date of Issuance: May 12, 2008
ATTACHMENT TO LICENSE AMENDMENT NO. 230 FACILITY OPERATING LICENSE NO. DPR-46 DOCKET NO. 50-298 Replace the following pages of the Facility Operating License No. DPR-46 and Appendix A Technical Specifications with the enclosed revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.
Facility Operating License REMOVE INSERT Page 3 of 5 Page 3 of 5 Technical Specifications REMOVE INSERT 3.7-8 3.7-8 3.7-9 3.7-9 3.7-10 3.7-10 5.0-17 5.0-17 5.0-18 5.0-18 5.0-19 5.0-19 5.0-20 5.0-20 5.0-21 5.0-21 5.0-22 5.0-22 5.0-23 5.0-23
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 230 TO FACILITY OPERATING LICENSE NO. DPR-46 NEBRASKA PUBLIC POWER DISTRICT COOPER NUCLEAR STATION DOCKET NO. 50-298
1.0 INTRODUCTION
By application dated January 14, 2008 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML08220330), Nebraska Public Power District (NPPD, the licensee), requested changes to the Technical Specifications (TSs) for Cooper Nuclear Station (CNS).
The proposed changes would revise the TS requirements related to control room envelope habitability in accordance with TS Task Force (TSTF) traveler TSTF-448-A, Control Room Habitability, Revision 3. This TS improvement was made available by the NRC on January 17, 2007 (72 FR 2022) as part of the consolidated line item improvement process (CLIIP).
On August 8, 2006, the commercial nuclear electrical power generation industry owners group Technical Specifications Task Force (TSTF) submitted a proposed change, TSTF-448, Revision 3, to the improved standard technical specifications (STS) (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 more effective and appropriate action, surveillance, and administrative STS requirements related to ensuring the habitability of the control room envelope (CRE).
In NRC Generic Letter 2003-01 (Reference 1), licensees were alerted to findings at facilities that existing TS surveillance requirements for the Control Room Emergency Filter System (CREF) may not be adequate. Specifically, the results of ASTM E741 (Reference 2) 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 generic letter, the industry and the NRC proposed revisions to CRE habitability system requirements contained in the STS, using the STS change traveler process. This effort culminated in Revision 3 to traveler TSTF-448, "Control Room Habitability," which the NRC staff approved on January 17, 2007.
Consistent with the traveler as incorporated into NUREG-1433, the licensee proposed revising action and surveillance requirements in Specification 3.7.4, "Control Room Emergency Filter System (CREF)," and adding a new administrative controls program, Specification 5.5.13, "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 U.S. Nuclear Regulatory Commission (NRC) Regulatory Guide (RG) 1.196, "Control Room Habitability at Light-water Nuclear Power Reactors," Revision 0, May 2003, (Reference 4) 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 RG 1.197, "Demonstrating Control Room Envelope Integrity at Nuclear Power Reactors,"
Revision 0, May 2003 (Reference 5), 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 STS, the CRE will be used to designate both. 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 Filter System (CREF)
The CREF (the term used at Cooper Nuclear Station for the Control Room Envelope Emergency Ventilation System, 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 CREF is designed to maintain a habitable environment in the control room envelope for 30 days of continuous occupancy after a Design Basis Accident (DBA) without exceeding five rem total effective dose equivalent (TEDE).
The CREF consists of a single-train capable of maintaining the habitability of the CRE. CNS was licensed with a single-train CREF system. The CREF is considered operable when the individual components necessary to limit operator exposure are operable. The CREF is considered operable when the associated:
$ Fans are OPERABLE (one supply fan, the emergency booster fan and the exhaust booster fan);
$ High efficiency particulate air (HEPA) filter and charcoal adsorber are not excessively restricting flow and are capable of performing their filtration functions; and,
$ Ductwork, valves, and dampers are OPERABLE, and air circulation can be maintained.
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. CNS was designed and constructed to meet the intent of the proposed 70 GDC for Nuclear Power Plants issued by the Atomic Energy Commission (AEC), as originally proposed in July. 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. NPPD states they meet Criterion 1: Those systems and components of reactor facilities which are essential to the prevention of accidents which could affect the public health and safety or to mitigation of their consequences shall be designed, fabricated, and erected to quality standards that reflect the importance of the safety function to be performed.
GDC 2, ADesign Basis for Protection Against Natural Phenomena,@ requires that SSCs important to safety be designed to withstand the effects of earthquakes and other natural hazards. NPPD states they were designed to Criterion 2: Those systems and components of reactor facilities which are essential to the prevention of accidents which could affect the public health and safety or to mitigation of their consequences shall be designed, fabricated, and erected to performance standards that will allow the plant to withstand additional forces imposed by natural phenomena.
In accordance with 10 CFR 50.48(a), CNS is required to have a fire protection plan that is in compliance with 1971 GDC 3. Conformance with Draft GDC 3 is therefore superseded in its entirety by 1971 GDC 3. 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 Design 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). NPPD states that this in not applicable. (An equivalent proposed-GDC (pre-1971) was not proposed). The CNS Environmental Qualification Program complies with 10 CFR 50.49. Systems and equipment which are required to function after accidents or transients are designed to withstand the most severe forces and environmental effects, including missiles from equipment failures. A High Energy Line Break (HELB) study demonstrated that the safe shutdown ability of CNS would not be degraded by a HELB. This study included the effects of pipe whip.
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. NPPD states that this is not applicable since CNS is a single unit nuclear power plant.
GDC 19, "Control Room," requires that a control 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. NPPD states that they were designed to Criterion 11. CNS is committed to the radiation protection provisions of the 1971 GDC 19 for the dose from a loss-of coolant accident (LOCA) and to the limits of 10 CFR 50.67 for the fuel handling accident (FHA). The CNS control room has adequate shielding to ensure personnel will not receive a radiation exposure in excess of five rem whole body for the duration of a LOCA or five Rem Total Effective Dose Equivalent (TEDE) for the duration of the FHA.
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-1430, TS 3.7.10, "Control Room Emergency Ventilation System (CREVS);"
$ NUREG-1431, TS 3.7.10, "Control Room Emergency Filtration System (CREFS);"
$ NUREG-1432, TS 3.7.11, "Control Room Emergency Air Cleanup System (CREACS);"
$ NUREG-1433, TS 3.7.4, "[Main Control Room Environmental Control (MCREC)]
System;" and
$ NUREG-1434, TS 3.7.3, "[Control Room Fresh Air (CRFA)] System."
In these specifications, the surveillance requirement associated with demonstrating the operability of the CRE boundary requires verifying that one CREEVS train subsystem 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 surveillance requirements. Other facilities that do not pressurize the CRE have only a system flow rate criterion for the emergency mode of operation. Regardless, the results of ASTM E741 (Reference 2) tracer gas tests to measure CRE unfiltered inleakage at facilities indicated that the differential pressure surveillance (or the alternative surveillance at non-pressurization facilities) is not a reliable method for demonstrating CRE boundary operability. That is, licensees were able to obtain differential pressure and flow measurements satisfying the SR limits even though unfiltered inleakage was determined to exceed the value assumed in the safety analyses.
In addition to an inadequate surveillance requirement, 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 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 RIS 2005-20 (Reference 3). AImposing 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 implemented 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 surveillance requirements, 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, Cooper Nuclear Station Adoption of TSTF-448, Revision 3, will assure that the facility's TS LCO for the CREF 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 CREF and the CRE boundary conform to 10 CFR 50.36(d)(2) and 10 CFR 50.36(d)(3). Their adoption will better assure that Cooper Nuclear Station CRE will remain habitable during normal operation and design basis accident conditions. These changes are, therefore, acceptable from a regulatory standpoint.
3.0 TECHNICAL EVALUATION
The NRC staff reviewed the proposed changes against the corresponding changes made to the STS 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 CREF at CNS 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 3.7.4, Control Room Emergency Filter (CREF) 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 to the latest information and references, correct factual errors, and achieve more consistency among the STS NUREGs.
Except for plant specific differences, all of these changes are consistent with STS as revised by TSTF-448, Revision 3.
The NRC staff compared the proposed TS changes to the STS and the STS markups and evaluations in TSTF-448. The staff verified that differences from the STS 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 5.5.10, "TS Bases Control Program," provides assurance that the licensee has established and will maintain the adequacy of the Bases. The proposed Bases for TS 3.7.4 refer to specific guidance in NEI 99-03, "Control Room Habitability Assessment Guidance," Revision 0, dated June 2001 (Reference 6), which the NRC staff has formally endorsed, with exceptions, through Regulatory Guide 1.196, AControl Room Habitability at Light-Water Nuclear Power Reactors,@ dated May 2003 (Reference 4).
3.2 Editorial Changes The licensee proposed editorial changes to TS 3.7.4, "CREF," to establish standard terminology, such as "control room envelope (CRE)" in place of "control room," except for the plant-specific name for the CREF (plant-specific name for CREEVS), and "radiological, chemical, and smoke hazards (or challenges)" in place of various phrases to describe the hazards that CRE occupants are protected from by the CREF. These changes improve the usability and quality of the presentation of the TS, have no impact on safety, and therefore, are acceptable.
3.3 TS 3.7.4, CREF The licensee proposed to establish new action requirements in TS 3.7.4, "CREF," for an inoperable CRE boundary. Currently, if CREF is determined to be inoperable due to an inoperable CRE boundary, existing Action A would apply and require restoring the system (and the CRE boundary) to operable status in 7 days. The existing Action is more restrictive than would be appropriate in situations for which CRE occupant implementation of compensatory measures or mitigating actions would temporarily afford adequate CRE occupant protection from postulated airborne hazards. To account for such situations, the licensee proposed to revise the action requirements to add a new Condition B, "CREF System inoperable due to inoperable CRE boundary in MODE 1, 2, or 3." New Action B would allow 90 days to restore the CRE boundary (and consequently, the CREF) to operable status, provided that mitigating actions are immediately implemented and within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> are verified to ensure, that in the event of a DBA, CRE occupant radiological exposures will not exceed the calculated dose of the licensing basis analyses of DBA consequences, and that CRE occupants are protected from hazardous chemicals and smoke.
The 24-hour Completion Time (CT) 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. The 90-day CT 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 of new Required Action B.3 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 CREF inoperable, Condition A is revised to state, "CREF System inoperable for reasons other than Condition B. The change to existing Condition A is less restrictive because this Condition will no longer apply in the event the CREF System is inoperable due to an inoperable CRE boundary during unit operation in Mode 1, 2, 3. This is acceptable because the new Action B establishes adequate remedial measures in this condition. With the addition of a new Condition B, existing Conditions B, C, D, and E are re-designated C, D, E, and F, respectively.
The licensee also proposed to modify the CREF 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 control of the 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 D of TS 3.7.4 that states, "CREF System inoperable due to an inoperable CRE boundary during movement of lately irradiated fuel assemblies in the secondary containment or during OPDRVs (operations with a potential for draining the reactor vessel)." The specified Required Actions proposed for this condition are the same as for the other existing condition for Action D, which states, ARequired Action and associated CT of Condition A not met during movement of lately irradiated fuel assemblies in the secondary containment or during OPDRVs.@ Accordingly, the new condition is stated with the other condition in Action D 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. This new condition in Action F is needed because proposed Action B will only apply in Modes 1, 2, and 3. As such, this change will ensure that the Actions table continues to specify a condition for an inoperable CRE boundary during refueling and OPDRVs. Therefore, this change is administrative and acceptable.
In the emergency radiation mode of operation, the CREF isolates normal unfiltered outside air intake path, 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 surveillance requirement (SR). This SR requires verifying that the CREF System operating in the emergency radiation mode can maintain a pressure of 0.1 inches water gauge relative to all adjacent areas during the pressurization mode of operation at a makeup flow rate of 990 cubic feet per minute (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, dated January 14, 2008, the licensee proposed to replace the CRE pressurization surveillance, SR 3.7.4.4, with an inleakage measurement SR and a CRE Habitability Program in TS Section 5.5, 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 3.7.4.4 is acceptable.
The proposed CRE inleakage measurement SR states, "Perform required CRE unfiltered air inleakage testing in accordance with the Control Room Envelope Habitability Program." The CRE Habitability Program TS, proposed TS 5.5.13, 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 (Reference 5). This guidance references ASTM E741 (Reference 2) 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 5.5.13, CRE Habitability Program The proposed administrative controls program TS is consistent with the model program TS in TSTF-448, Revision 3. In combination with SR 3.7.4.4, this program is intended to ensure the operability of the CRE boundary, which as part of an operable CREF 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 design basis accident (DBA) conditions without personnel receiving radiation exposures in excess of five rem total effective dose equivalent (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 (Reference 4), which endorsed, with exceptions, NEI 99-03 (Reference 6). 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 (Reference 5), 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. 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, will be performed as part of assessing the CRE boundary at a frequency of 18 months. 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 3.7.4, 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 number 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 5.5.13 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 5.5.13, 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 consistent with the model application, and are acceptable.
4.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Nebraska 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 installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. 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 consideration, and there has been no public comment on such finding published February 12, 2008 (73 FR 8070). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). 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 CONCLUSION
The Commission has concluded, based on 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.
7.0 REFERENCES
- 1. NRC Generic Letter 2003-01, "Control Room Habitability," dated June 12, 2003, (GL 2003-01)
- 2. ASTM E 741 - 00, "Standard Test Method for Determining Air Change in a Single Zone by Means of a Tracer Gas Dilution," 2000, (ASTM E741)
- 3. NRC Regulatory Issue Summary 2005-20, Rev.1: Revision to NRC Inspection Manual Part 9900 Technical Guidance, "Operability Determinations & Functionality Assessments for Resolution of Degraded and Nonconforming Conditions Adverse to Quality or Safety,"
dated April 16, 2008 (RIS 2005-20)
- 4. Regulatory Guide 1.196, "Control Room Habitability at Light-Water Nuclear Power Reactors," Revision 0, dated May 2003
- 5. Regulatory Guide 1.197, "Demonstrating Control Room Envelope Integrity at Nuclear Power Reactors," Revision 0, May 2003
- 6. NEI 99-03,"Control Room Habitability Assessment Guidance," Revision 0, dated June 2001
- 7. Nebraska Public Power District Letter #NLS2008009 Application to Revise Technical Specifications Regarding Control Room Envelope Habitability in Accordance With TSTF-448-A, Revision 3, Using the Consolidated Line Item Improvement Process, dated January 14, 2008 Principal Contributor: B. Heida Date: May 12, 2008