ML063470223
ML063470223 | |
Person / Time | |
---|---|
Site: | Turkey Point ![]() |
Issue date: | 12/12/2006 |
From: | Moroney B NRC/NRR/ADRO/DORL/LPLII-2 |
To: | Stall J Florida Power & Light Co |
Moroney B, NRR/DORL, 415-3974 | |
Shared Package | |
ML063470276 | List: |
References | |
TAC MD2493, TAC MD2494 | |
Download: ML063470223 (20) | |
Text
December 12, 2006 Mr. J. A. Stall Senior Vice President, Nuclear and Chief Nuclear Officer Florida Power and Light Company P.O. Box 14000 Juno Beach, Florida 33408-0420
SUBJECT:
TURKEY POINT PLANT, UNITS 3 AND 4 - ISSUANCE OF AMENDMENTS REGARDING EXTENSION OF THE INTAKE COOLING WATER PUMP ALLOWED OUTAGE TIME (TAC NOS. MD2493 AND MD2494)
Dear Mr. Stall:
The U.S. Nuclear Regulatory Commission has issued the enclosed Amendment No. 232 to Renewed Facility Operating License No. DPR-31 for the Turkey Point Plant, Unit No. 3, and Amendment No. 227 to Renewed Facility Operating License No. DPR-41 for the Turkey Point Plant, Unit No. 4. These amendments consist of changes to the Technical Specifications (TSs) in response to your License Amendment Request No. 186 dated June 21, 2006 (L-2006-146),
as supplemented by letter dated December 12, 2006 (L-2006-268).
The amendments revise TS 3.7.3, Intake Cooling Water System, Action a, to increase the allowed outage time for one inoperable intake cooling water pump from 7 days to 14 days.
A copy of the Safety Evaluation is also enclosed. The Notice of Issuance will be included in the Commission's biweekly Federal Register notice.
Sincerely,
/RA/
Brendan T. Moroney, Project Manager Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-250 and 50-251
Enclosures:
- 1. Amendment No. 232 to DPR-31
- 2. Amendment No. 227 to DPR-41
- 3. Safety Evaluation cc w/enclosures: See next page
ML063470223 NRR-058 OFFICE LPL2-2:PM LPL2-2:LA BC:APLB BC:SBPB OGC LPL2-2:BC(A)
NAME BMoroney BClayton LMrowca JSegala SHamrick DPickett by memo by memo dated dated DATE 12/ 12 / 06 12/12 / 06 12/12/ 06 12/12 / 06 12/12 / 06 12/12 / 06 Mr. J. A. Stall TURKEY POINT PLANT Florida Power and Light Company cc:
Mr. William E. Webster Attorney General Vice President, Nuclear Operations Department of Legal Affairs Florida Power & Light Company The Capitol P.O. Box 14000 Tallahassee, Florida 32304 Juno Beach, FL 33408-0420 Michael O. Pearce M. S. Ross, Managing Attorney Plant General Manager Florida Power & Light Company Turkey Point Nuclear Plant P.O. Box 14000 Florida Power and Light Company Juno Beach, FL 33408-0420 9760 SW. 344th Street Florida City, FL 33035 Marjan Mashhadi, Senior Attorney Florida Power & Light Company James Connolly, Licensing Manager 801 Pennsylvania Avenue, NW. Florida Power and Light Company Suite 220 Turkey Point Nuclear Plant Washington, DC 20004 9760 SW 344th Street Florida City, FL 33035 T. O. Jones, Site Vice President Turkey Point Nuclear Plant Becky Ferrare Florida Power and Light Company Licensing Department Administrator 9760 SW. 344th Street Turkey Point Nuclear Plant Florida City, FL 33035 9760 SW 344th Street Florida City, FL 33035 County Manager Miami-Dade County Mark Warner, Vice President 111 Northwest 1 Street, 29th Floor Nuclear Operations Support Miami, Florida 33128 Florida Power and Light Company P.O. Box 14000 Senior Resident Inspector Juno Beach, FL 33408-0420 Turkey Point Nuclear Plant U.S. Nuclear Regulatory Commission Mr. Rajiv S. Kundalkar 9762 SW. 344th Street Vice President - Nuclear Engineering Florida City, Florida 33035 Florida Power & Light Company P.O. Box 14000 Mr. William A. Passetti, Chief Juno Beach, FL 33408-0420 Department of Health Bureau of Radiation Control 2020 Capital Circle, SE, Bin #C21 Tallahassee, Florida 32399-1741 Mr. Craig Fugate, Director Division of Emergency Preparedness Department of Community Affairs 2740 Centerview Drive Tallahassee, Florida 32399-2100
FLORIDA POWER AND LIGHT COMPANY DOCKET NO. 50-250 TURKEY POINT PLANT, UNIT NO. 3 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 232 Renewed License No. DPR-31
- 1. The Nuclear Regulatory Commission (the Commission) has found that:
A. The application for amendment by Florida Power and Light Company (the licensee) dated June 21, 2006, as supplemented December 12, 2006, 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. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 3.B of Renewed Facility Operating License No. DPR-31 is hereby amended to read as follows:
(B) Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A, as revised through Amendment No. 232, are hereby incorporated in the license. The Environmental Protection Plan contained in Appendix B is hereby incorporated into the license.
The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3. This license amendment is effective as of its date of issuance and shall be implemented upon receipt.
FOR THE NUCLEAR REGULATORY COMMISSION
/RA/
Douglas V. Pickett, Acting Chief Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the License and Technical Specifications Date of Issuance: December 12, 2006
FLORIDA POWER AND LIGHT COMPANY DOCKET NO. 50-251 TURKEY POINT PLANT, UNIT NO. 4 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 227 Renewed License No. DPR-41
- 1. The Nuclear Regulatory Commission (the Commission) has found that:
A. The application for amendment by Florida Power and Light Company (the licensee) dated June 21, 2006, as supplemented December 12, 2006, 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. Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 3.B of Renewed Facility Operating License No. DPR-41 is hereby amended to read as follows:
- 2. Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A, as revised through Amendment No. 227, are hereby incorporated in the license. The Environmental Protection Plan contained in Appendix B is hereby incorporated into the license.
The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 4. This license amendment is effective as of its date of issuance and shall be implemented upon receipt.
FOR THE NUCLEAR REGULATORY COMMISSION
/RA/
Douglas V. Pickett, Acting Chief Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the License and Technical Specifications Date of Issuance: December 12, 2006
ATTACHMENT TO LICENSE AMENDMENT AMENDMENT NO. 232 TO RENEWED FACILITY OPERATING LICENSE NO. DPR-31 AMENDMENT NO. 227 TO RENEWED FACILITY OPERATING LICENSE NO. DPR-41 DOCKET NOS. 50-250 AND 50-251 Replace Page 3 of Renewed Facility Operating License DPR-31 with the attached Page 3.
Replace Page 3 of Renewed Facility Operating License DPR-41 with the attached Page 3.
Replace the following page of the Appendix A Technical Specifications with the attached page.
The revised page is identified by amendment number and contains marginal lines indicating the area of change.
Remove page Insert page 3/4 7-14 3/4 7-14
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 232 TO RENEWED FACILITY OPERATING LICENSE NO. DPR-31 AND AMENDMENT NO. 227 TO RENEWED FACILITY OPERATING LICENSE NO. DPR-41 FLORIDA POWER AND LIGHT COMPANY TURKEY POINT UNIT NOS. 3 AND 4 DOCKET NOS. 50-250 AND 50-251
1.0 INTRODUCTION
By application dated June 21, 2006, as supplemented by letter dated December 12, 2006, Florida Power and Light Company (the licensee) submitted a License Amendment Request (LAR) to the U.S. Nuclear Regulatory Commission (NRC), requesting a change to the Turkey Point Unit 3 and 4 Operating License in accordance with Title 10 of the Code of Federal Regulations (10 CFR), Section 50.90. The proposed amendment would revise Technical Specification (TS) 3.7.3 Required Action a to extend the allowed outage time (AOT) associated with one inoperable Intake Cooling Water (ICW) pump from 7 days to 14 days.
The licensees supplementary submittal dated December 12, 2006, provided clarifying information that did not change the scope of the proposed amendment as described in the original notice of proposed action published in the Federal Register and did not change the initial proposed no significant hazards determination.
2.0 REGULATORY EVALUATION
The licensee submitted the proposed amendment as a risk-informed change. The regulatory criteria/guidelines related to risk-informed submittals are:
- Regulatory Guide (RG)1.174, "An Approach for Using Probabilistic Risk Assessment
[PRA] in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis," describes a risk-informed approach, acceptable to the NRC, for assessing the nature and impact of proposed licensing-basis changes by considering engineering issues and applying risk insights. This RG also provides risk acceptance guidelines for evaluating the results of such evaluations.
- RG 1.177, "An Approach for Plant-Specific, Risk-Informed Decisionmaking:
Technical Specifications," describes an acceptable risk-informed approach specifically for assessing proposed TS changes in allowed outage times (AOTs).
This regulatory guide also provides risk acceptance guidelines for evaluating the results of such evaluations.
One acceptable approach to making risk-informed decisions about proposed TS changes is to show that the proposed changes meet five key principles stated in RG 1.174, Section 2 and RG 1.177, Section B:
- 1. The proposed change meets the current regulations unless it is explicitly related to a requested exemption or rule change.
- 2. The proposed change is consistent with the defense-in-depth philosophy.
- 3. The proposed change maintains sufficient safety margins.
- 4. When proposed changes result in an increase in core-damage frequency or risk, the increases should be small and consistent with the intent of the Commissions Safety Goal Policy Statement.
- 5. The impact of the proposed change should be monitored using performance measurement strategies.
The first three principles pertain to traditional engineering considerations and are evaluated in Section 3.3 below; whereas the last two principles involve risk considerations that are evaluated in Section 3.4.
For permanent TS changes, RG 1.174 and RG 1.177 provide numerical risk acceptance guidelines that are helpful in determining whether or not the fourth key principle has been satisfied. These guidelines are not to be applied in an overly prescriptive manner; rather, they provide an indication, in numerical terms, of what is considered acceptable. The intent in comparing risk results with the risk acceptance guidelines is to demonstrate, with reasonable assurance, that the fourth key principle has been satisfied.
3.0 TECHNICAL EVALUATION
3.1 Description of System/Component and Current Requirements The information in this section was derived from the licensees amendment request.
The ICW system provides cooling water to the safety related component cooling water (CCW) heat exchangers and to the turbine plant cooling water (TPCW) heat exchangers, and supplies water to the lube water system. A separate ICW system is provided for each nuclear unit. The TPCW and lube water systems are intended to serve nonsafety related functions only. The ICW pumps are not credited for fire water sources. The normal fire water system utilizes the raw water tanks (which store fresh city water) as suction for the electric and backup diesel driven fire pumps. The screen wash pumps can provide a backup source of fire protection water from the intake canal.
The ICW system includes three ICW pumps, tie headers, two independent supply headers, piping, valves, basket strainers, and those components required to take ICW from the plant
cooling canals via the intake structure and supply the CCW, TPCW, and lube water systems and return the ICW to the plant cooling canal system.
One, two or three pumps are operated as required to support normal plant conditions. The ICW system provides sufficient redundancy so that at least one ICW pump will continue to operate to handle heat loads from design basis accidents following a postulated single active failure. A single ICW pump, however, is limited in its ability to supply the required cooling water to the CCW heat exchangers during an accident when flow is also allowed to continue through the TPCW heat exchangers. The system design provides automatic isolation of the TPCW heat exhangers upon loss of instrument air, loss of electrical (DC) power, or safety injection actuation. Controls are provided both locally and in the control room to manually isolate the TPCW heat exchangers.
The ICW system safety function is to remove the heat load from the CCW system during accident conditions to support both reactor heat removal and containment heat removal requirements.
Based on the identified ICW system design basis and the electrical independence of the ICW pumps, there is no credible single active failure event that could reduce the number of available ICW pumps below the design basis minimum of one operating pump.
3.2 Detailed Description of the Proposed Change The licensee proposes to revise TS 3.7.3, "Intake Cooling Water System," Action a, to extend the TS AOT for an inoperable ICW pump from 7 days to 14 days. The proposed TS reads as follows:
With only two ICW pumps with independent power supplies OPERABLE, restore the inoperable ICW pump to OPERABLE status within 14 days or be in HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />. The provisions of Specification 3.0.4 are not applicable.
The proposed changes will allow a AOT of 14 days for the ICW pump maintenance or testing activities. This will allow an additional seven days beyond the current TS-allowed AOT.
3.3 Traditional Engineering Evaluation The traditional engineering evaluation presented below addresses the first three key principles of the staffs philosophy of risk-informed decisionmaking, which concern compliance with current regulations, evaluation of safety margins, and evaluation of defense-in-depth.
3.3.1 Compliance with Current Regulations The licensee does not propose to deviate from existing regulatory requirements and compliance with existing regulations is maintained. Therefore, with respect to compliance with current regulations, the NRC staff considers the proposed TS change to be acceptable.
3.3.2 Evaluation of Safety Margins Design basis analyses and system design criteria are not impacted by the proposed change and, consequently, safety margins are not affected.
3.3.3 Evaluation of Defense-in-Depth Attributes The NRC staff has reviewed the information that was provided by the licensee in regards to the defense-in-depth attributes in accordance with the guidance that is specified by RG 1.177 for making risk-informed changes to TS requirements. The staffs evaluation of the defense-in-depth attributes is provided below.
- A reasonable balance among prevention of core damage, prevention of containment failure, and consequence mitigation is preserved.
The proposed change involves an extension of the current TS allowed outage time for one inoperable ICW pump from 7 days to 14 days. The ICW system includes three ICW pumps for each unit. The ICW System safety function is to remove the heat load from the CCW System during accident conditions to support both reactor heat removal and containment heat removal requirements. One ICW pump is capable of providing the required flow to meet 100 percent of the postaccident heat removal capability. The system is required to be capable of performing its safety functions with a single active failure assumed. The ICW to TPCW isolation valves are required to automatically isolate ICW flow to the TPCW system following an accident to ensure adequate ICW flow is diverted to the CCW system heat exchangers for postaccident heat removal in the event of a single failure that results in only one ICW pump being available. If the single active failure is assumed to be a power operated valve, two ICW pumps can be assumed to be operable. The two operable ICW pumps can provide sufficient flow to accommodate the flow diverted through the TPCW system. During normal operation, two ICW pumps are in operation to support normal plant heat loads. Consequently, the balance among the prevention of core damage, prevention of containment failure, and consequence mitigation is unaffected by the proposed change.
- Over-reliance on programmatic activities to compensate for weaknesses in plant design is avoided.
The proposed change involves an extension of the current TS AOTs for TS 3.7.3, Action a. The proposed changes does not include any new programmatic activities, therefore the reliance on programmatic activities is not impacted by the proposed change .
- System redundancy, independence, and diversity are preserved commensurate with the expected frequency, consequences of challenges to the system, and uncertainties (e.g., no risk outliers).
The licensee stated that the ICW pumps are provided and designed with adequate independence, redundancy, capacity, and testability to ensure communication with the ultimate heat sink required to avoid undue risk to the health and safety of the public.
This cooling source provides this capacity assuming a failure of a single active
component. One of the three ICW pumps, together with two CCW heat exchangers can accomplish the heat removal safety function. Therefore, if one ICW pump is inoperable, then a single failure of one of the remaining two operable pumps can be accommodated in the event of an accident. Since a single failure of one ICW pump can be accommodated whether or not the third pump is operable, extending the AOT for an out of service ICW pump has no impact on the system design basis.
Given these considerations, the staff agrees that sufficiently redundant, independent, and diverse capabilities will be maintained for performing critical safety functions during the proposed allowed outage time.
- Defenses against potential common cause failures are preserved, and the potential for the introduction of new common cause failure mechanisms is assessed.
The licensee stated that the proposed change does not involve a change in the design, configuration, or method of operation of the plant. The proposed change will not alter the manner in which equipment operation is initiated, nor will the functional demands on credited equipment be changed. The proposed change allows operation of a Turkey Point unit to continue while an ICW pump is repaired and tested. The proposed extension does not affect the interaction of an ICW pump with any system whose failure or malfunction can initiate an accident. As such, no new failure modes and no new potential common cause for failure are being introduced Given these considerations, the staff agrees that defenses against potential common cause failures are preserved, and the potential for the introduction of new common cause failure mechanisms is assessed during the proposed allowed outage time.
- Independence of barriers is not degraded.
The proposed change does not directly impact the independence of the barriers or otherwise cause them to be degraded. Therefore, the staff finds that the independence of barriers will not be degraded by the proposed AOT.
- Defenses against human errors are preserved.
The proposed change does not directly impact the defenses against human errors during the proposed allowed outage time.
- The intent of the general design criteria in Appendix A to 10 CFR Part 50 is maintained.
The proposed change does not modify the plant design bases or the design criteria that were applied to structures, systems, and components during plant licensing.
Consequently, the plant design with respect to the general design criteria is not affected by the proposed change.
Based on the above review of defense-in-depth attributes, the staff finds that defense-in-depth will be adequately maintained during the proposed AOT.
3.4 Risk Evaluation The risk evaluation presented below addresses the last two key principles of the staffs philosophy of risk-informed decision making, those which concern changes in risk and performance measurement strategies. These key principles were evaluated by using the three-tiered approach described in Chapter 16.1 of the Standard Review Plan (SRP) and RG 1.177.
- Tier 1 - The first tier evaluates the licensee's PRA and the impact of the change on plant operational risk, as expressed by the change in core damage frequency (CDF) and the change in large early release frequency (LERF). The change in risk is compared against the acceptance guidelines presented in RG 1.174.
The first tier also evaluates plant risk during the period when equipment is taken out of service (OOS) per the license amendment, as expressed by the incremental conditional core damage probability (ICCDP) and incremental conditional large early release probability (ICLERP). The incremental risk is compared against the acceptance guidelines presented in RG 1.177.
- Tier 2 - The second tier addresses the need to preclude potentially high-risk plant configurations that could result if equipment, in addition to that associated with the proposed license amendment, is taken OOS simultaneously, or if other risk-significant operational factors, such as concurrent system or equipment testing, are also involved. The objective of this part of the review is to ensure that appropriate restrictions on dominant risk-significant plant configurations associated with the AOT extension are in place.
- Tier 3 - The third tier addresses the licensee's overall configuration risk management program (CRMP) to ensure that adequate programs and procedures are in place for identifying risk-significant plant configurations resulting from maintenance or other operational activities and taking appropriate compensatory measures to avoid such configurations. The CRMP is to ensure that equipment removed from service prior to or during the proposed extended AOT period will be appropriately assessed from a risk perspective.
3.4.1 Tier 1: PRA Capability and Insights The Tier 1 staff review involved two aspects: (1) evaluation of the validity of the PRA and its application to the proposed AOT extension; and (2) evaluation of the PRA results and insights stemming from its application.
3.4.1.1 Evaluation of PRA Validity To determine whether the PRA used in support of the proposed AOT extension is of sufficient quality, scope, and level of detail, the staff evaluated the relevant information provided by the licensee in their submittal and supplements. The staff's review of the licensee's submittal focused on the validity of the licensee's PRA model to analyze the risks stemming from the proposed AOT extension and did not involve an in-depth review of the licensee's PRA. The following information from the licensees submittal provided the basis for this portion of the staffs review.
There have been numerous reviews of the Turkey Point Probabilistic Safety Assessment (PSA),
dating back to the original individual plant examination (IPE), which had multiple levels of review. The first consisted of normal engineering quality assurance practices carried out by the organization performing the analysis. A qualified individual with knowledge of PSA methods and plant systems performed an independent review of the results for each task. This represented a detailed check of the input to the PSA model and provided a high degree of quality assurance.
The second level of review was performed by plant personnel not directly involved with the development of the PSA model. This review was performed by individuals from Operations, Technical Staff, Training, and the Independent Safety Engineering Group, who reviewed the system description notebooks and accident sequence description. This provided diverse expertise with plant design and operations knowledge to review the system descriptions for accuracy.
The third level of review was performed by PSA experts from ERIN Engineering. This review provided broad insights on techniques and results based on experience from other plant PSAs.
The review team reviewed the PRA development procedures, as well as the output products.
Comments obtained from all the review sources were incorporated, as appropriate, into the work packages, and the final product. Following the Turkey Point IPE submittal to the NRC on June 25, 1991, it was reviewed extensively by the NRC and NRC contractors. In fact, the Turkey Point IPE was one of the few IPE submittals to receive a Step 1 and a Step 2 review by the NRC. The Step 2 review consisted of a team of NRC representatives and contractors visiting the licensee to conduct a week-long, extensive review of the Turkey Point IPE.
Following these reviews, the Turkey Point IPE was revised in early 1992, and the licensee received the NRC Safety Evaluation Report (SER) for the Turkey Point IPE on October 15, 1992. The SER concluded that the Turkey Point IPE had met the intent of Generic Letter 88-20.
In January 2002, the Turkey Point PSA model underwent an official peer review conducted by Westinghouse using PSA contractors and utility PSA analysts. This review produced two "A" Facts and Observations (F&Os) and 29 "B" F&Os. All of the "A" findings have been resolved, and all but four of the "B" level findings have been resolved. Two of these "B" findings are documentation issues, and therefore have no impact on this analysis. One is a Level 2 issue, which suggests performing a sensitivity analysis on a Containment Event Tree top event probability. Given the margin of the ICLERP in this application and the fact that the F&O only asks for a sensitivity analysis, this is extremely unlikely to have any impact. The last "B" F&O is an internal flooding issue. The F&O simply states that the reduction in the internal events core damage frequency (CDF) as a result of refinements and updates of the model since the original IPE has now made the original IPE internal flooding analysis CDF of 5E-7 per year a more significant contributor to the overall CDF. While this is true, there are factors that need to be considered. One is the fact that the internal flooding CDF is still only about 8 percent of the internal events CDF. Two, the internal flooding analysis was a screening-type analysis, which typically gives a conservative result. Third, the focus of this application is the ICW pumps, which are located in the intake structure, which has no potential for internal floods. Therefore, the remaining open "B" F&Os are judged to have no effect on the conclusions of this analysis of the risk associated with the extension of the ICW pump TS AOT.
Based upon the above, the staff finds that the PRA used in support of the proposed ICW pump AOT extension is of sufficient quality, scope, and level of detail to analyze the risks stemming from the proposed AOT extension, consistent with the guidance in RG 1.174 and SRP Chapters 16.1,19 and 19.1.
3.4.1.2 Evaluation of PRA Results and Insights The licensee provided a risk assessment of the proposed license amendment for extending the ICW pump AOT of TS 3.7.3 Required Action A from 7 days to 14 days. The CDF and LERF results for preventive and corrective maintenance can be found in Table 1.
TABLE 1 CDF and LERF D-Bus Aligned to A D-Bus Aligned to B Case CDF/yr LERF/yr CDF/yr LERF/yr Baseline 6.10E-6 3.79E-7 6.14E-06 3.79E-7 Bounding ICW 6.70E.-06 Pump 6.63E-06 3.79E-7 3.79E-7 Unavailabilities 5.27E-07 CDF/LERF 2.311E-10 5.68E-07 2.94E-10 The above results are considered very small using the RG 1.174 acceptance guidelines.
TABLE 2 ICCDP and ICLERP D-Bus Aligned to A D-Bus Aligned to B Pump OOS ICCDP ICLERP ICCDP ICLERP Corrective Maintenance 3A 3.87E-7 3.02E-10 N/A N/A 3B N/A N/A 3.84E-7 3.01E-10 3C 3.73E-7 2.89E-10 3.72E-7 2.89E-10 Preventive Maintenance 3A 1.55E-8 1.26E-11 N/A N/A 3B N/A N/A 1.37E-8 1.23E-11 3C 4.76E-9 7.79E-13 3.79E-9 4.82E-13 The calculated ICCDP and ICLERP are less than the RG 1.177 acceptance guidelines of 5.0E-07 for ICCDP and 5.0E-08 for ICLERP. The results in Table 2 show that in all cases, the calculated ICCDP when an ICW pump is inoperable for preventive maintenance are less than the 5E-07 criteria listed in RG 1.177.
The staff concludes that the risk impact of the extension of the AOT of the ICW pump lies in Region III of Figures 3 and 4 contained in RG 1.174. Therefore, in accordance with the RG 1.174 risk acceptance guidelines, the licensees proposed license amendment results in an acceptable increase in risk that is very small and consistent with the NRCs Safety Goal Policy Statement. The staff also concludes that the calculated ICCDP and ICLERP when an ICW pump is unavailable for preventive maintenance during the extended AOT are less than the RG 1.177 acceptance guidelines of 5.0E-07 for ICCDP and 5.0E-08 for ICLERP for the full 14-day AOT. Therefore, the staff finds that the licensees first tier risk evaluation of PRA validity and results, performed in accordance with Chapters 16.1 and 19 of the SRP and RG 1.177, is acceptable.
3.4.1.3 External Events 3.4.1.3.1 Internal Fire The licensee provided an explanation of the fire modeling performed at Turkey Point in the LAR. Specific risk insights of refining the Turkey Point Individual Plant Examination of External Events (IPEEE) fire risk for the cable spreading room and control room provide reasonable assurance that the fire risk for those areas is very low. The Turkey Point IPEEE concluded that there were no severe accident vulnerabilities due to internal fires.
The revised fire risk estimates for the cable spreading room and control room are at least two orders of magnitude lower than that reported in the original Turkey Point IPEEE. Although the IPEEE fire risk model has not been updated, applicable fire risk insights can still be obtained by reviewing the nature of the fire risk contributors for risk-significant fire zones.
The IPEEE analysis identified six risk-significant fire zones (i.e., control room, cable spreading room, 480V motor control center rooms (fire zones 63 and 61), and intake structures (fire zones 119 and 120)). The incremental risk from fire in any of these fire areas with one ICW pump being out of service is small because either two trains of ICW pumps are available or the fire-induced CCDP is not significantly affected. The capability to avoid the fire-related loss of cooling water events is due to the availability of the other ICW pumps and cross-tie capability of the opposite unit CCW. Even if the fire of concern occurs during the small fraction of the year in which the ICW pump is assumed to be unavailable for maintenance, the capability to cross-tie the CCW from the opposite unit would remain available. Therefore, the additional plant risk from fire induced loss of cooling water events due to the proposed extended AOT is very low.
The staff finds that, based on the conservative fire risk assessment performed by the licensee, the fire risk of extending the ICW pump AOT is small and consistent with RG 1.174 guidance.
3.4.1.3.2 Seismic and Other External Events The licensee provided a brief explanation of the seismic modeling performed at Turkey Point in the LAR. The Turkey Point IPEEE submission for seismic risk was based on the seismic analysis resolving USI A-46. The Turkey Point IPEEE submission indicated that the seismic risk is low.
A plant-specific seismic adequacy evaluation identified components as seismic outliers. These outliers were addressed by implementing relevant plant improvements or procedures. The capacities of condensate storage tanks and refueling water storage tanks were evaluated and determined to meet the seismic design basis of 0.15g peak ground acceleration.
For earthquakes beyond design basis accidents, the quantified risk is very conservative to compensate for the uncertainties in the seismic hazard and seismic fragility. Nevertheless, given the large safety factor generally embedded in the seismic design, in combination with measures taken in the resolution of A-46 issues, the seismic risk is low for Turkey Point.
From a severe accident risk perspective, hurricanes are much less significant than other external events, because they develop slowly and with advance warning that allows both preparation for and elimination of accident sequences. For example, many accident scenarios such as loss-of-coolant accidents, steam generator tube rupture, and anticipated transient without scram are reduced significantly or totally eliminated for Turkey Point because, as required by plant procedures, the units are placed in a shutdown condition prior to the onset of a hurricane. The decay heat is therefore reduced by a factor of two to three depending on when the loss of critical safety functions is postulated. The time available to take actions after hurricane induced failures is thus increased, significantly reducing the core damage frequency.
The staff observes that should a hurricane develop when an ICW pump is out of service, there would be two remaining redundant pumps.
The core damage frequency contribution from external events reported in the Turkey Point IPEEE submission (tornado, transportation and nearby facilities, and others) is estimated to be less than 1.0E-06/yr. The capability to cross-tie the other unit was not credited in the Turkey Point IPEEE submission.
The TS AOT is only applicable in Modes 1 through 4, therefore shutdown risk is not affected by the AOT extension.
The staff finds that, based on the conservative seismic, high wind and shutdown risk assessment performed by the licensee, the risk of extending the ICW pump AOT is small and consistent with RG 1.174 guidance.
In summary, the NRC staff finds that all Tier 1 evaluations were performed in accordance with appropriate NRC guidance and are acceptable.
3.4.2 Tier 2: Avoidance of Risk-Significant Plant Configurations The second tier evaluates the capability of the licensee to recognize and avoid risk-significant plant configurations that could result if equipment, in addition to that associated with the proposed license amendment, is taken OOS simultaneously or if other risk-significant operational factors, such as concurrent system or equipment testing, are also involved.
RG 1.177 Section 2.3 describes one possible method for performing a Tier 2 evaluation for risk-informed TS AOT Extension LARs. This method involves evaluation of combinations of equipment OOS (including the specific equipment for which the LAR is requesting the AOT extension) against the Tier 1 ICCDP acceptance guideline (ICCDP < 5E-7). For combinations of equipment unavailability (configurations) found to exceed this risk threshold, a discussion of the controls in place to prevent these configurations from occurring, or the compensatory
measures that will be put in place to limit the risk increase, during the AOT extension period is required.
In response to a NRC question, the licensee evaluated potential risk-significant configurations that may be encountered during the extended AOT period should other risk-significant equipment experience unplanned unavailability. Due to low risk associated with one pump being OOS for 14 days, no Tier 2 high-risk plant configurations are identified.
The NRC has reviewed the configurations and have concluded that the licensees second tier risk evaluation, performed in accordance with Chapters 16.1 and 19 of the SRP and RG 1.177, is acceptable.
3.4.3 Tier 3: Risk-Informed Configuration Risk Management The third tier assesses the licensees program to ensure that the risk impact of OOS equipment is appropriately evaluated prior to performing any maintenance activity. The need for this third tier stems from the difficulty of identifying all possible risk-significant configurations under the second tier that could ever be encountered.
The licensee describes the CRMP in place for the Turkey Point plant in the LAR. While in the extended ICW pump AOT, overall plant risk will be managed by the existing Maintenance Rule (a)(4) program. This program utilizes the Equipment Out of Service software to evaluate unique plant configurations. Turkey Point plant procedure O-ADM-225, On Line Risk Assessment and Management, addresses the actions required to be taken at each risk level.
The Work Controls department assesses and manages the risk of work week activities in advance, while control room personnel assess and manage the risk of emergent work.
In response to a staff question, the licensee confirmed that the CRMP in use at Turkey Point does not credit recovery of the OOS equipment.
Based on the licensees description of their CRMP, the staff finds that the licensees third tier risk evaluation, performed in accordance with Chapters 16.1 and 19 of the SRP and RG 1.177, is acceptable.
3.5 Staff Findings In summary, the staff finds that the licensee's proposed change to extend the AOT associated with TS 3.7.3 Required Action a from 7 days to 14 days is acceptable because the five key principles of risk-informed decisionmaking identified in RG 1.174 and RG 1.177 have been satisfied. Thus, the staff has concluded that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in this 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.
4.0 STATE CONSULTATION
Based upon a letter dated May 2, 2003, from Michael N. Stephens of the Florida Department of Health, Bureau of Radiation Control, to Brenda L. Mozafari, Senior Project Manager,
U.S. Nuclear Regulatory Commission, the State of Florida does not desire notification of issuance of license amendments.
5.0 ENVIRONMENTAL CONSIDERATION
These amendments involve a change in the 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 amendments involve 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 amendments involve no significant hazards consideration, and there has been no public comment on such finding (71 FR 53717). Accordingly, these amendments meet 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 amendments.
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 amendments will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributors: O. Hopkins R. Hernandez Date: December 12, 2006