ML052230428
| ML052230428 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 08/12/2005 |
| From: | Colburn T NRC/NRR/DLPM/LPD1 |
| To: | Spina J Nine Mile Point |
| Colburn T, NRR/DLPM, 415-1402 | |
| References | |
| TAC MC8061 | |
| Download: ML052230428 (16) | |
Text
August 12, 2005 Mr. James A. Spina Vice President Nine Mile Point Nine Mile Point Nuclear Station, LLC P. O. Box 63 Lycoming, NY 13093
SUBJECT:
NINE MILE POINT NUCLEAR STATION, UNIT NO. 1 - ISSUANCE OF AMENDMENT RE: EMERGENCY TECHNICAL SPECIFICATION CHANGE REQUEST - LAKE WATER MAXIMUM TEMPERATURE LIMIT (TAC NO.
Dear Mr. Spina:
The Commission has issued the enclosed Amendment No. 190 to Facility Operating License No. DPR-63 for the Nine Mile Point Nuclear Station, Unit No. 1 (NMP-1). The amendment consists of changes to the Technical Specifications (TSs) in response to your application transmitted by letter dated August 8, 2005, as supplemented August 11, 2005.
The amendment revises TS 3.3.7, Containment Spray System, specifically, increasing the maximum lake water temperature limit in specification f. from 81 °F to 83 °F.
A copy of the related Safety Evaluation is enclosed. A Notice of Issuance will be included in the Commission's next regular biweekly Federal Register notice.
Sincerely,
/RA/
Timothy G. Colburn, Senior Project Manager, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-220
Enclosures:
- 1. Amendment No. 190 to DPR-63
- 2. Safety Evaluation cc w/encls: See next page
August 12, 2005 Mr. James A. Spina Vice President Nine Mile Point Nine Mile Point Nuclear Station, LLC P. O. Box 63 Lycoming, NY 13093
SUBJECT:
NINE MILE POINT NUCLEAR STATION, UNIT NO. 1 - ISSUANCE OF AMENDMENT RE: EMERGENCY TECHNICAL SPECIFICATION CHANGE REQUEST - LAKE WATER MAXIMUM TEMPERATURE LIMIT (TAC NO.
Dear Mr. Spina:
The Commission has issued the enclosed Amendment No. 190 to Facility Operating License No. DPR-63 for the Nine Mile Point Nuclear Station, Unit No. 1 (NMP-1). The amendment consists of changes to the Technical Specifications (TSs) in response to your application transmitted by letter dated August 8, 2005, as supplemented August 11, 2005.
The amendment revises TS 3.3.7, Containment Spray System, specifically, increasing the maximum lake water temperature limit in specification f. from 81 °F to 83 °F.
A copy of the related Safety Evaluation is enclosed. A Notice of Issuance will be included in the Commission's next regular biweekly Federal Register notice.
Sincerely,
/RA/
Timothy G. Colburn, Senior Project Manager, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-220
Enclosures:
- 1. Amendment No. 190 to DPR-63
- 2. Safety Evaluation cc w/encls: See next page Accession Number: ML052230428 OFFICE PDI-1\PM PDI-1\LA SPLB\SC SPSB\SC(A) OGC PDI-1/SC NAME TColburn MOBrien for SLittle SJones MKotzalas AHodgdon JBoska for RLaufer DATE 8/12/05 8/12/05 8/12/05 8/12/05 8/12/05 8/12/05 OFFICIAL RECORD COPY
DATED: August 12, 2005 AMENDMENT NO. 190 TO FACILITY OPERATING LICENSE NO. DPR-63 NINE MILE POINT UNIT NO. 1 PUBLIC PDI R/F RLaufer SLittle MOBrien TColburn OGC GHill (2)
TBoyce JHernandez SJones EThrom MKotzalas ACRS JTrapp, RI DLPM DPR cc: Plant Mailing list
NINE MILE POINT NUCLEAR STATION, LLC (NMPNS)
DOCKET NO. 50-220 NINE MILE POINT NUCLEAR STATION, UNIT NO. 1 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 190 License No. DPR-63
- 1. The Nuclear Regulatory Commission (the Commission) has found that:
A. The application for amendment by Nine Mile Point Nuclear Station, LLC (the licensee) dated August 8, 2005, as supplemented August 11, 2005, 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 2.C.(2) of Facility Operating License No. DPR-63 is hereby amended to read as follows:
(2) Technical Specifications The Technical Specifications contained in Appendix A, which is attached hereto, as revised through Amendment No. 190, is hereby incorporated into this license. Nine Mile Point Nuclear Station, LLC shall operate the facility in accordance with the Technical Specifications.
- 3. This license amendment is effective as of the date of its issuance and shall be implemented within 5 days.
FOR THE NUCLEAR REGULATORY COMMISSION
/RA JBoska for/
Richard J. Laufer, Chief,Section I Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation
Attachment:
Changes to the Technical Specifications Date of Issuance: August 12, 2005
ATTACHMENT TO LICENSE AMENDMENT NO. 190 TO FACILITY OPERATING LICENSE NO. DPR-63 DOCKET NO. 50-220 Replace the following page of Appendix A, Technical Specifications, with the attached revised page. The revised page is identified by amendment number and contains marginal lines indicating the area of change.
Remove Page Insert Page 161 161
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 190 TO FACILITY OPERATING LICENSE NO. DPR-63 NINE MILE POINT NUCLEAR STATION, LLC NINE MILE POINT NUCLEAR STATION, UNIT NO. 1 DOCKET NO. 50-220
1.0 INTRODUCTION
By letter dated August 8, 2005, as supplemented August 11, 2005, Nine Mile Point Nuclear Station, LLC (NMPNS or the licensee) submitted a request for a change to the Nine Mile Point Nuclear Station, Unit No. 1 (NMP1), Technical Specifications (TSs). The requested change would revise TS 3.3.7, Containment Spray System, specifically, increasing the maximum lake water temperature limit in specification f. from 81 °F to 83 °F. The licensee requested that the amendment request be approved on an emergency basis in accordance with Title 10 of the Code of Federal Regulations (10 CFR), Part 50, Section 50.91(a)(5). A recent lake water temperature increase of unanticipated magnitude, considering historical norms, has resulted in Unit No. 1 being in imminent danger of exceeding the maximum allowable lake water temperature, which would result in a NMP1 shutdown to a hot shutdown condition within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and a cold shutdown within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
2.0 REGULATORY EVALUATION
Lake Ontario serves as the ultimate heat sink for the operating and decay heat produced by various NMP1 plant components during normal operation, anticipated operational occurrences, and accidents. As described in the NMP1 Updated Final Safety Analysis Report (UFSAR), Section III-F, lake water is drawn through an offshore intake structure, flows through the intake tunnel, is filtered by trash racks and screens, and enters the screenhouse intake forebays. The containment spray system, the emergency diesel generator (EDG) raw water cooling system, and the service water system transfer heat from plant components to the lake water. The pumps for these systems all take suction from the intake forebay in the screenhouse. The cooling water from these systems is returned to the discharge channel in the screenhouse, flows through the discharge tunnel, and returns to the lake through the discharge structure. In addition, the nonsafety-related circulating water system pumps and fire protection water (FPW) system pumps take suction from the screenhouse forebay.
The containment spray system is described in the NMP1 UFSAR, Section VI-B. This system removes energy from the primary containment following a design-basis loss-of-cooling accident (LOCA) to reduce containment pressure and temperature and maintain them below containment design pressure and temperature limits. The containment spray system pumps take suction from the torus. The pump discharge flow passes through the shell side of the containment spray heat exchangers, where it is cooled by raw lake water, and is then directed to the drywell and torus spray headers. Each of the four containment spray heat exchangers is supplied cooling water by a
dedicated containment spray raw water pump that takes suction from the screenhouse forebay.
After removing heat from the containment spray water, the raw water is returned to the screenhouse discharge channel.
The EDG raw water cooling system removes heat generated by operation of the EDGs. For each of the two EDGs, cooling water is supplied to the associated raw water cooling heat exchanger by a dedicated raw water pump that takes suction from the screenhouse forebay. After removing heat from the EDG coolant system, the raw water is returned to the screenhouse discharge channel.
The EDG raw water cooling system pumps operate automatically any time that the associated EDG is running.
The service water system, described in UFSAR Section X-F, is a once-through system that supplies cooling water from Lake Ontario to various essential and non-essential components throughout the plant, as required during normal operation, shutdown conditions, and accidents. The service water system provides cooling to the reactor building closed loop cooling (RBCLC) heat exchangers, which are safety-related components. The service water system also provides cooling water to the turbine building closed loop cooling (TBCLC) heat exchangers, the reactor building heating, ventilation, and air conditioning (HVAC) components, turbine building HVAC components, radwaste building area coolers, steam jet air ejector precoolers and vent cooler, and screenwash pumps, which are nonsafety-related components. The service water system consists of two service water pumps, two emergency service water (ESW) pumps, strainers, and associated piping and valves. During normal plant operations, either of the two normal service water pumps supplies sufficient cooling water to the main headers to satisfy plant cooling flow requirements. In the event of a loss of offsite power (LOOP), the normal service water pumps would be unavailable, and service water requirements for safety-related equipment in the reactor building would be provided by either of the two ESW pumps, which are powered by the EDGs.
NMP1 TS 3.3.7, specification f., states, The containment spray system shall be considered operable by verifying that lake water temperature does not exceed 81 °F. Specification g., states, If specification f cannot be met commence shutdown within one hour and be in hot shutdown within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and cold shutdown within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
The proposed change to TS 3.3.7, Containment Spray Temperature, to increase the maximum lake temperature from 81 °F to 83 °F, affects the containment pressure and temperature calculations, and the torus water temperature calculations.
The containment pressure and temperature should satisfy the intent of 10 CFR, Part 50, Appendix A, General Design Criteria (GDC) 16 and 50 to maintain an essentially leak-tight containment and remain below the design pressure and temperature of the containment.
The containment temperature should also satisfy the criteria of 10 CFR 50.49 for the environmental qualification of equipment inside containment.
The torus water temperature should not exceed the temperature which ensures adequate available net positive suction head (NPSH) to the pumps taking suction from the torus in order to satisfy the intent of GDC 38 for adequate containment cooling and GDC 35 for abundant core cooling following a LOCA. Additionally, 10 CFR, Part 50, Appendix J, requires that the peak containment pressure must be less than or equal to the value of Pa specified in the TSs.
3.0 TECHNICAL EVALUATION
3.1 Containment Response The parameters of interest for this license amendment request (LAR) are the peak containment pressure, and the peak torus water temperature. The licensee used the SHEX-04 computer program to perform the containment related analyses to support this LAR. SHEX is described in NEDE-30911, SHEX-04 User's Manual, Class II, General Electric Company, August 1985, and in SHEX-04V User's Manual (Addendum to SHEX-04 User's Manual), NEDE-30911-1, June 1994.
The staff has accepted SHEX for similar licensing evaluations, for example for Edwin I. Hatch Unit 1 (SHEX Model Description, PDR ADOCK 050000321, 9807130260, 980706).
The licensee evaluated the effects of the increased lake water temperature on the initial drywell and torus water temperatures used in the accident analyses. The drywell is cooled by the safety-related reactor building closed loop cooling (RBCLC) heat exchangers which use the service water system for cooling. The service water system uses the raw lake water for cooling. The RBCLC heat exchangers have adequate margin to maintain the drywell temperature below 95 °F, the value used in the accident analyses, with the 2 °F increase in the lake water temperature. The initial torus water temperature used in the accident analyses is 85 °F, the maximum allowable value specified in TS 3.3.2.b. Operating data have shown that the torus water temperature remains less than 80 °F during the summer months. The primary source of heat to the torus water is ambient heat from the reactor building and heat from reactor coolant system leakage, for example relief valve leakage. The licensee concluded that the torus water temperature value used in the accident analysis is unlikely to be exceeded as a result of the increase in the lake water temperature. The staff agrees with the licensees assessment that the initial conditions used in the accident analyses are not affected by the increase in the lake water temperature.
An important part of the containment analysis is the heat transfer capabilities of the containment spray coolers. The containment spray heat exchangers are cooled directly by the raw lake water.
The licensee evaluated two scenarios. For the design-basis LOCA analysis, one containment spray cooler raw water pump is manually started at 15 minutes. For the second case, the emergency operating procedures (EOPs) were used to determine (a) when containment spray could be stopped, (b) when to initiate containment spray based on torus pressure increases, and (c) when to initiate torus cooling on high torus water temperature.
The containment peak pressure occurs within about 60 seconds after the onset of the design-basis LOCA. Because the containment spray coolers are not credited for the first 15 minutes of the accident, the peak pressure is not affected by the proposed change. Because the peak pressure remains unchanged, the TS value for Pa also remains unchanged. The short-term maximum torus water temperature, for the first 15 minutes, is also unaffected by the proposed change because no credit is taken for the containment spray coolers during this period. The long-term containment response to the design-basis LOCA was assessed by the licensee. The licensee stated that the 2 °F increase in the containment spray cooler raw water temperature has an insignificant effect on the containment spray droplet temperature and the long-term containment response would not be significantly impacted. The Nuclear Regulatory Commission (NRC) staff agrees with this assessment.
The long-term post-accident containment temperature profile is to some extent changed because of the higher containment spray cooler temperature. This licensee stated that the change would be on the order of 1 °F to 2 °F. The NRC staff agrees that the increase in the temperature profile is on the order 1 °F to 2 °F for the long-term post-accident period. The licensee also evaluated the critical building areas and concluded that the temperatures remain within the current baseline and overall EQ assessments.
The peak torus water temperature is important in determining the available NPSH of the pumps taking suction from the torus. The licensee performed accident analyses with SHEX-04 using a conservative lake water temperature value of 84 °F, 1 °F over the proposed value. Based on a conservative containment heat exchanger performance coefficient of 241 BTU/sec-°F, the peak torus water temperature remains below the current value, 165 °F, used to assess the available NPSH for pumps taking suction from the torus. For the design-basis LOCA case, the peak torus water temperature is 163.8 °F. For the EOP case, the peak torus water temperature is 164.9 °F.
Therefore, the available NPSH is not affected by the proposed change.
The containment spray raw water system pumps need an NPSH of 31 ft. at design flows. The minimum available NPSH for these pumps, based on a minimum screenhouse forebay level of 14 ft. and a lake water temperature of 81 °F, is 40.1 ft., providing a margin of about 9 ft. The 2 °F increase in the lake water temperature would decrease the minimum available NPSH by less than 0.1 ft., and the licensee concluded that the containment spray raw water systems pump operability would not be adversely impacted by the proposed change. The staff agrees with the licensees assessment.
3.2 System Performance The licensee stated that engineering analyses have been performed to support plant operation with a 2 °F increase in lake water temperature from the current TS limit (81 °F) to the proposed limit of 83 °F. The licensee evaluated the capability of affected structures, systems and components to perform their safety functions under the proposed conditions, and the impact on accidents and transients described in the NMP1 Updated Final Safety Analysis Report (UFSAR).
The licensees evaluation showed that the increase in temperature will not result in a significant reduction of NPSH available to the raw water system pumps and the EDG raw water cooling system pumps. The licensee also demonstrated that operating stresses on the piping and supports will not be significantly affected by the temperature increase.
The service water (SW) system provides cooling water to the RBCLC heat exchangers. The analysis showed that the temperature increase did not affect the RBCLC ability to provide the required cooling for the safety-related loads and loads required for safe shutdown assuming the most-limiting scenario, which is a LOOP.
The licensee analyzed the effects of the water temperature increase on the core spray system cooling capacity and concluded that the short-term and long term maximum torus water temperatures following a LOCA do not change from the calculated values in the existing design-basis accident; thus, it will have no impact on the calculated peak clad temperature.
The existing design-basis evaluation of safe shutdown capability credits the nonsafety-related shutdown cooling system. The shutdown cooling system rejects heat to the RBCLC system, which is transferred to the lake water via the SW system. The licensees analysis showed that the RBCLC is capable of maintaining the cooling water supply temperature to the shutdown cooling heat exchangers within the allowable value of 95 °F.
The licensee evaluated the impact of the temperature increase to the station blackout (SBO) event, which assumes LOOP and failure of the EDGs. The SBO analysis does not credit the cooling capability of any system that uses lake water as the cooling medium. Therefore the only affected component credited in the analysis is the diesel fire pump, which is used to provide make-up to cope with an assumed reactor recirculation pump seal failure. The diesel fire pump draws lake water from the screenhouse forebay. However, the 2 °F temperature increase was determined to have an insignificant impact on the NPSH available for the diesel fire pump.
The licensee stated that the ability to achieve cold shutdown conditions within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> during a fire event (required by 10 CFR Part 50, Appendix R), with or without offsite power, is not adversely affected by the increase in temperature.
In its amendment request, the licensee provided an analysis of the containment response for large-break LOCAs under the proposed temperature increase. The licensee described a series of modifications (done earlier this year) to the design-basis torus temperature response, which included revisions to the NMP1-specific assumptions and corrections to the determination of decay heat values. The lake water temperature value remained the same, as described in the UFSAR.
As part of these modifications, the licensee revised its assumptions for the performance of the containment spray heat exchangers. The heat exchanger performance coefficient was reduced from 256 Btu/sec-°F (assumed in the UFSAR) to 235 Btu/sec-°F, a value more consistent with the Tubular Exchanger Manufacturers Association (TEMA) fouling assumptions for Great Lakes water.
This resulted in an increase in the peak calculated torus water temperature from 160 °F to 163 °F for the design-basis assumption case, and from 162.2 °F to 164.9 °F for the EOP assumptions case. To support its analysis for the 2 °F temperature limit increase, the licensee increased the heat exchanger performance coefficient from 235 to 241 Btu/sec-°F. With this adjustment, the peak calculated torus water temperature remains under 165 °F, which is the maximum analyzed peak torus water temperature. The licensee justified the decision based on a review of the heat exchanger performance testing and the existing preventive maintenance practices. In its supplemental letter, dated August 10, 2005, the licensee provided a description of the performance testing methodology for the containment spray system heat exchangers. The licensee stated that the performance testing is carried under its Preventive Maintenance (PM) Program. The PM interval is for the heat exchangers to be cleaned every refueling outage (i.e., every 2 years). The licensee stated that it is using the performance testing of the containment spray heat exchangers to validate that the cleaning interval is effective in maintaining the heat exchangers such that they meet their design-basis heat removal requirements (i.e., a heat exchanger performance coefficient of 241 Btu/sec-°F).
The NRC staff reviewed this documentation and concluded that the existing testing and inspection procedures are adequate, and demonstrate that the proposed performance coefficient is consistent with the as-tested parameters; thus, they provide reasonable assurance that the design-basis assumptions will be met under the proposed amendment. Therefore, the NRC staff concludes that the proposed license amendment to revise the maximum lake temperature limit from 81 °F to 83 °F is acceptable.
4.0 EXIGENT CIRCUMSTANCES
The licensee requested emergency processing of the proposed amendment request and provided the following rationale for its request for emergency processing:
The reason for the emergency is that unusually prolonged hot weather in the area has resulted in elevated Lake Ontario temperatures. High temperatures during the daytime, in conjunction with little cooling at night, have resulted in elevated Lake Ontario temperatures. The recent weather conditions have resulted in lake temperatures exceeding the anticipated temperature trends based on lake temperature measurements from previous years. On August 4, 2005, the lake temperature peaked within 2 °F of the limit. We foresee the possibility that the lake water temperature may exceed the 81 °F limit during periods of sustained hot weather conditions over the next seven days and the remaining summer months. In addition, there are no controllable measures that can be taken to immediately reduce the temperature of the lake.
These recent meteorological conditions have caused an elevated lake water temperature beyond the control of the plant and the opportunity to make a timely application does not exist, therefore an emergency situation exists.
Lake water temperature is routinely monitored in accordance with the requirements of the NMP1 Technical Specifications [TSs]. [A] Review of data from previous years indicates that the previous highest peak of 77.9 °F was recorded on August 1, 1999 and was below the current TS limit of 81 °F. (Graph
- 1) [See graphs in the August 11, 2005, supplement to the application]
Comparison of the data in 2005 versus 1999 showed similar trends through July.
(Graph 1) At the beginning of August, the 1999 daily peak lake temperature showed a gradual decreasing trend. However, the 2005 lake temperature has not shown a similar decreasing trend. At this point NMPNS began investigating the possibility of increasing the NMP1 ultimate heat sink maximum temperature above 81 °F. (Graph 1) On August 4, the 2005 peak lake water temperature exceeded the 1999 peak value, reaching 79 °F. This departure from previous experience could not have been anticipated or avoided. (Graph 1) Predicted maximum and minimum air temperature in the site area through August 15 of this year exceed those that were recorded during the same period in 1999.
Thus, there is a distinct possibility that the lake temperature will continue to rise.
(Graphs 2 and 3) Lake water daily maximum temperature remains above previously observed values. (Graph 4) Based on the above, the emergency situation could not have been avoided and the criteria for issuance of an emergency license amendment contain[ed] in 10 CFR 50.91(a)(5) have been fulfilled.
The NRC staff has reviewed the licensees rationale for determination that an emergency situation exists. The NRC staff has determined that as defined in 10 CFR 50.91(a)(5), an emergency situation exists in that failure to act may result in an unnecessary shutdown of NMP1 given the likelihood of increased lake temperatures beyond the TS 3.3.7.f maximum lake temperature limit and that the licensee has provided information to show that it could not have
avoided the situation. Therefore, the NRC staff has determined that the circumstances for emergency treatment stipulated in 10 CFR 50.91(a)(5) have been satisfied.
5.0 FINAL NO SIGNIFICANT HAZARDS CONSIDERATION
DETERMINATION In the regulations at 10 CFR 50.92, the Commission states that it may make a final determination that a license amendment involves no significant hazards consideration determination if operation of the facility in accordance with the 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 previously evaluated; or (3) involve a significant reduction in a margin of safety. As required by 10 CFR 50.91(a), the licensee has provided its analysis of the issue of no significant hazards consideration, which is presented below:
- 1. Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?
Response: No.
The proposed change allows plant operation to continue with a maximum lake water temperature of 83° F. This 2° F increase in allowable lake water temperature will not affect the normal operation of the plant to the extent that it would make any accident more likely to occur. The lake water temperature is not itself an accident initiator, and raising the maximum temperature limit does not involve any plant hardware changes or new operator actions that could serve to initiate an accident. The potential impact of the proposed change on the ability of the plant to mitigate postulated accidents has been analyzed. These analyses demonstrate that safety-related systems and components that rely on lake water as the cooling medium are capable of performing their intended safety functions at the higher lake water temperature, and that containment integrity and equipment qualification are maintained. Thus, the proposed change will have no adverse effect on plant operation, or the availability or operation of any accident mitigation equipment. Therefore, there will be no increase in the probability or consequences of an accident previously evaluated.
- 2. Does the proposed change create the possibility of a new or different kind of accident from any accident previously evaluated?
Response: No.
The proposed change does not introduce any new modes of plant operation and will not result in a change to the design function or operation of any structure, system, or component that is used for accident mitigation. The proposed lake water temperature increase does not result in any credible new failure mechanisms, malfunctions, or accident initiators not considered in the design and licensing basis. The engineering analyses performed to support the proposed change demonstrate that affected safety-related systems and components are capable of performing their intended safety functions at the elevated lake water temperature. Therefore, the proposed change will not create
the possibility of a new or different kind of accident from any previously evaluated.
- 3. Does the proposed change involve a significant reduction in a margin of safety?
Response: No.
NMPNS has performed an evaluation of the affected safety systems to ensure their safety functions can be met with a lake temperature of 83° F. The higher lake water temperature represents a slight reduction in the design margin in terms of the ability of the selected systems to remove accident heat loads.
However, as part of the evaluation, it was verified that these safety systems will still be capable of performing their intended safety functions. The proposed change will have no adverse effect on plant operation or equipment important to safety. The plant responses to accidents will not be significantly affected and the accident mitigation equipment will continue to function as assumed in the accident analysis. Therefore, there will be no significant reduction in a margin of safety.
Based on the above considerations, the NRC staff concludes that the amendment meets the three criteria of 10 CFR 50.92. Therefore, the NRC staff has made a final determination that the amendment does not involve a significant hazards consideration.
6.0 STATE CONSULTATION
In accordance with the Commission's regulations, the New York State official was notified of the proposed issuance of the amendment. The State official had the following comments:
We [the State of New York] would have no objection to NRC approving the request if it was done for a temporary period. Since we have had one day to review and discuss the matter and have some questions and concerns about the need for such an amendment, we do object to NRC approving a permanent change on such a short notice emergency basis. Our understanding is that the water temperature in the Lake is currently under 78 degrees F at the surface and it should soon begin a cooling trend which would make the need for the amendment moot. However, we do not want to see the plant have to shut down unnecessarily and, therefore, would not object to NRC granting temporary Tech.
Spec. relief. More permanent action would require further data and discussion for the responsible New York agencies to be comfortable that public health and safety are being fully protected.
The NRC staff has determined that the licensee has met the criteria of 10 CFR 50.91(a)(5) for emergency consideration with respect to the requested amendment in that failure to act on the part of the NRC may result in an unnecessary plant shutdown and that the circumstances leading to this emergency situation could not have been avoided. The lake water temperature on the morning of receiving the state comments was 78.5 °F and had risen to nearly 80 °F the previous evening. Lake temperatures have been peaking near midnight. While the forecast for
the next few days may be slightly cooler than that for the preceding few days, it does not guarantee that the licensee will not exceed the maximum lake temperature limit in the NMP1 TSs and be required to conduct an immediate shutdown. If this were to occur on or about the same time as the recent temperature peaks have been observed, the NRC might then be in a position where it could not act quickly enough to prevent the licensee from commencing an unnecessary plant shutdown in order to comply with its NMP1 TSs. The NRC staff has determined that the licensees justification for increasing the maximum allowable lake temperature by 2 °F is acceptable. This acceptability is not time-dependent, and would be acceptable whether it is for a short or permanent duration. The NRC thanks the State for its comments, but has determined that it will proceed with issuance of the amendment having given due consideration to the States comments and the likelihood that failure to act in a timely manner might result in an unnecessary plant shutdown.
7.0 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 made a final finding that the amendment involves no significant hazards consideration. 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.
8.0 CONCLUSION
The NRC staff has concluded, based on the considerations discussed above, that (1) the amendment does not (a) involve a significant increase in the probability or consequences of an accident previously evaluated or, (b) create the possibility of a new or different kind of accident from any previously evaluated or, (c) involve a significant reduction in a margin of safety and therefore, the amendment does not involve a significant hazards consideration; (2) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (3) such activities will be conducted in compliance with the Commissions regulations, and (4) 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 Contributors: E. Throm J. Hernandez T. Colburn Date: August 12, 2005
Nine Mile Point Nuclear Station, Unit No. 1 cc:
Mr. Michael J. Wallace Mark J. Wetterhahn, Esquire President Winston & Strawn Nine Mile Point Nuclear Station, LLC 1400 L Street, NW c/o Constellation Energy Group Washington, DC 20005-3502 750 East Pratt Street Baltimore, MD 21202 Supervisor Town of Scriba Mr. Mike Heffley Route 8, Box 382 Senior Vice President and Chief Oswego, NY 13126 Nuclear Officer Constellation Generation Group Carey W. Fleming, Esquire 1997 Annapolis Exchange Parkway Senior Counsel Suite 500 Constellation Generation Group, LLC Annapolis, MD 21401 750 East Pratt Street, 17th Floor Baltimore, MD 21202 Regional Administrator, Region I U.S. Nuclear Regulatory Commission Ms. Deb Katz, Executive Director 475 Allendale Road Nuclear Security Coalition King of Prussia, PA 19406 c/o Citizens Awareness Network P.O. Box 83 Resident Inspector Shelburne Falls, MA 01370 U.S. Nuclear Regulatory Commission P.O. Box 126 Lycoming, NY 13093 Charles Donaldson, Esquire Assistant Attorney General New York Department of Law 120 Broadway New York, NY 10271 Mr. Paul D. Eddy Electric Division NYS Department of Public Service Agency Building 3 Empire State Plaza Albany, NY 12223 Mr. Peter R. Smith, President New York State Energy, Research, and Development Authority 17 Columbia Circle Albany, NY 12203-6399