ML20199D832
| ML20199D832 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 01/12/1999 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20199D819 | List: |
| References | |
| NUDOCS 9901200222 | |
| Download: ML20199D832 (3) | |
Text
__
l
/ptar e
m UNITED STATES 8
NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 30666 4 001
- s s s *,o SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION l
RELATED TO AMENDMENT NOS.133 AND 95 TO FACILITY OPERATING LICENSE NOS. NPF-39 AND NPF-85 PECO ENERGY COMPANY LIMERICK GENERATING STATION. UNITS 1 AND 2 DOCKET NOS. 50-352 AND 50-353
1.0 INTRODUCTION
l By letter dated October 15,1998, the licensee submitted a request for changes to the Limerick Generating Station (LGS), Units 1 and 2 Technical Specifications (TS). The proposed amendments would add a new TS section and a new TS Bases to incorporate a special test exception to allow inservice testing (IST) and hydrostatic testing to be performed in OPERATIONAL CONDITION (OPCON) 4 (i.e., Cold Shutdown) when the average reactor coolant temperature exceeds 200 *F and is less than or equal to 212 *F, which normally corresponds to OPCON 3 (i.e., Hot Shutdown). The proposed TS changes are based on the Section 3.10.1 of NUREG-1433, Revision 1, " Standard Technical Specifications, General Electric Plants, BWR/4,' dated April 1995, except that a 212 *F temperature limit has been specified.
2.0 BACKGROUND
Inservice hydrostatic testing and inservice leak pressure tests required by Section XI of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code are performed prior to the reactor going critical after a refueling outage. The minimum temperatures (at the required press.tres) allowed for these tests are determined from the reactor pressure vessel (RPV) pressure and temperature (PR) limits required by Limiting Condition for Operation (LCO) 3.4.6, Reactor Coolant System Pressure / Temperature Limits. These limits are based on the fracture toughness of the reacter vessel, taking into account anticipated vessel neutron fluence. With increased reactor fluence over time, the minimum allowable vessel temperature increases at a given pressure.
Periodic updates to the reactor coolant system (RCS) P6 limit curves are performed as necessary, based upon the results of analysis ofirradiated surveillance specimens removed from the vessel.
The proposed TS changes involve adding a new TS section and supporting Bases to the LGS, Units 1 and 2, TS to include provisions for a Special Test Exception. New LCO requirements will be established for Unit 1 (i.e, TS Section 3/4.10.8) and Unit 2 (i.e., TS Section 3/4.10.8) which specify that the average reactor coolant water temperature in TS Table 1.2 for OPCON 4 may be increased to 212 *F, and that operation is not considered to be in OPCON 3, in order to allow performance of inservice leak and hydrostatic testing, provided the following OPCON 3 LCOs are met:
i I
l 9901200222 990112 PDR ADOCK 05000352 P
s
, 1. LCO 3.3.2 lsolation Actuation Instrumentation, Table 3.3.21, Functions 7.a. 7.c.1, 7.c.2, and 7.d;
- 2. LCO 3.6.5.1.1 Reactor Enclosure Secondary Containment integrity;
- 2. LCO 3.6.5.1.2 Refueling Area Secondary Containment Integrity;
- 4. LCO 3.6.5.2.1 Reactor Enclosure Secondary Containment Automatic Isolation Valves;
- 5. LCO 3.6.5.2.2 Refueling Area Secondary Containment Automatic isolation Valves; and 6 LCO 3.6.5.3 Standby Gas Treatment System.
The Applicability of the proposed LCO is OPCON 4 with average reactor coolant water temperature greater than 200 *F and less than or equal to 212 'F.
New TS Bases Section B 3/4.10.8 (Unit 1) and B 3/4.10.8 (Unit 2) will also be added in support of the new Special Test Exception TS requirements.
In addition, a new TS section and Bases section reference (i.e.,3/4.10.7, B 3/4.10.7) will also be added to the Unit 1 TS only. These TS and Bases sections were added to the Unit 1 TSs in order to maintain consistency in the numbering sequence of the TS sections for Units 1 and 2. These sections contain no information and will be designated as " reserved."
3.0 EVALUATION The proposed TS changes involve revising TS Section 3/4.10 to include a new Special Test Exception allowing the reactor to be considered in OPCON 4 during inservice leak or hydrostatic testing with a reactor coolant water temperature greater than 200 *F and less than or equal to 212 *F. This is an exception to certain OPCON 3 requirements, including primary containment. The proposed TS changes will permit unrestricted access to the primary containment for the performance of required inspections. The inservice leak or hydrostatic test is performed water solid, or near water solid, when the stored energy in the reactor core is very low and the potential for failed fuel and a subsequent increase in coolant activity above Specification 3/4.4.5 limits are minimal. In addition, the Secondary Containment, which includes automatic isolation dampers and the Standby Gas Treatment System (SGTS), will be operable and capable of handling airbome radioactive material from leaks that could occur during the performance of inservice leak or hydrostatic testing.
Airborne radioactive material would not be significant in the event of a leak since there will be little or no flashing (i.e., conversion to steam) of reactor coolant. Requiring the Secondary Containment to be operable will assure that potential airbome radioactive material from leaks will be filtered through the SGTS to limit any radiation releases to the environment.
In the event of a large primary coolant system leak, the reactor vessel would rapidly depressurize, allowing the low pressure core cooling systems (i.e., Low Pressure Coolant injection (LPCI) and Core Spray (CS)) to operate. The capability of the LPCI and CS systems, as required in OPCON 4 by LOO 3.5.2, 'ECCS Shutdown," would be adequate to keep the core flooded under this low decay heat load condition. Small system leaks would be detected by leakage inspections before significant inventory loss occurred.
' ~~
o
- 3-Based on the NRC staff's evaluation, it le concluded that the proposed TS changes will assure acceptable consequences of any postulated accidents and are, therefore, acceptable. In addition, the revisions to Bases are consistent with the TS changes.
4.0 STATE CONSULTATION
in accordance with the Commission's regulations, the Pennsylvania State official was notified of the proposed issuance ~of the amendments. The State official had no comments.
5.0 ENVIRONMENTAL CONSIDEfBTIQH The amendments change a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and change the surveillance requirements. 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 (63 FR 64120). Accordingly, the 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 environmentalimpact 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 Contributor: B. Buckley Date:
January 12, 1999 1
.,