ML20209G873
| ML20209G873 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 04/22/1987 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20209G815 | List: |
| References | |
| NUDOCS 8705010088 | |
| Download: ML20209G873 (3) | |
Text
{{#Wiki_filter:.. ', t t \\" [gbg i 'o, UNITED STATES ![ 3 ,.s NUCLEAR REGULATORY COMMISSION - t WASHINGTON, D. C, 20555 g SAFETf EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO. 35 TO FACILITY OPERATING LICENSE NO. NPF-22 3 PENNSYLVANIA POWER & LIGHT COMPANY i SUS 00EHANNA STEAM ELECTRIC STATION UNIT 2 i i DOCKET NO. 50-388 i
1.0 INTRODUCTION
i t7 By a letter dated June 23, 1986, PennylvaniaPowerandLightCompany (the licensee) requested a change in the Technical Specification for high setpoint for the Main Steam Line Radiation Monitors. The change was re-qttested because of a number of spurious reactor trips caused by the existing st:tpoint. The amendment, as proposed by the licensee, changes the Unit 2 Technical Specifications to revise the Main Steam Line Radiation-High Setpoint from three times ncrmal background (three times setting) to seven times normal background (seven times setting). The proposed Technical Specification change increasing the setpoint for Main Steam Line Radiation-High would prevent unwarranted reactor scrams and yet assure that gross cladding failures will be promptly detected. The change would also' assure simi-larity of configuration between Unit 1 (which presentlyLhas a setting at seven times the background) and Unit 2. 2.0 EVALUATION The licensee has stated that the Main Steam Line Radiation Monitors are not relied upon for any design basis accident analyses. The staff agrees with this statement. Furthermore, the staff finds that the purpose of these monitors is to provide a quick means of detecting gross degradation of the fuel. The current setpoint for the radiation monitors.(three times back-1 ground) corresponds to the cladding failure of approximately 15 fuel rods, s The requested setpoint of seven times background would increase this value ,co an equivalent cladding failure of approximately 44 idel rods. When compared with the total number of fuel rods in the core (47,368), the s failures associated with either the three times setting or the seven times setting corresponds to a very small percentage of failed rods. The con-i sequences of the failure of 44 fuel rods can be conservatively determined by comparison with the control rod drop design basis accident which is assumed to produce cladding failure of 770 fuel rods. The projected thyroid and whole body doses for this design basis control rod drop-1 ~ accident at the Exclusion Area and Low Population Zone Boundaries are 1.47 Rem and less than 0.1 Rem, and 0.32 Rem and less than 0.1 Rem, respectively. S Because the projected failed fuel value for the seven times setting is better than a factor of ten less than that projected for the rod drop '/ accident, the projected doses would be more than a factor of ten less. l i 8705020088 870422 DR ADOCK 05000388 PDR (
2 1-N Consequently, the doses for the new setpoint would be much less than a Rem for both the thyroid and whole body at both the Exclusion Area and Low Population Zone boundaries for design basis accidents. i An additional consideration is that fuel design and fuel management employed at current boiling water reactors (BWR's) has resulted in significantly less failed fuel during cperation than existed at the time the monitoring require-ment was imposed. t' The staff concludes that the requested change is acceptable because: 1) the monitors perform no functions for mitigating the consequences of design basic accidents; 2) the setpoint chance would result in only a small increase in the projected doses; arld'3) the current vintage BWP fuel is performing in a manner superior to the fuel in place prior to the require-- ment for monitor installation. It's the staff's intent that such accident monitors should be set high enough to avoid spurious reactor trips, but low enough to detect significant fuel degradation. The staff concludes that the licensee meets this criterion with a setpoint of seven times background and therefore, finds:the licensee's request acceptable.
3.0 ENVIRONMENTAL CONSIDERATION
This amendment involves a change in the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The staff has determined that the amendment involves no significant increase in the amounts, and no significerit chavde 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 Comission bas previously issued a proposed finding that this amendment involves no significant hazards consideration, and there has been no public comment on such finding. Accordingly, this amendment meets the elicibility criteria forcategoricalexclusionsetforthin10CFR51.22(c)(9). Pursuant to 10 1 CFR 51.22(b) no environeental impact statement nor environmental assessment need be prepared in connection with the issuance of this amendment.
4.0 CONCLUSION
The Commission made a proposed determination that the amendment involves no significant hazards consideration which was published in the Federal Reoister (52 FR 7691) on March 12, 1987, and consulted with the state of Pennsylvania. No public coments were received, and the state of Pennsylvania did not have any comments. The staff 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, and (2) such. activities will be conducted in compliance with the Comission's regulations and the issuance of this amendment will not be inimical to the comon defense ar.d security nor to the health and safety of the public. Principal Contributor: Mohan C. Thadani, Project Directorate No. 3, DBL Dated: April 22,1987
AMENDMENT NO. 35 TO FACILITY OPERATING LICENSE NO. NPF SUSQUEHANNA, UNIT 2 i DISTRIBUTION: 50kket1NoE503388 NRC PDR Local PDR PRC Systern NSIC BWD-3 r/f MThadani (2) EHylton EAdensam Attorney, OELD CMiles RDiggs JPartlow l BGrimes Edordan LHarmon TBarnhart(4) EButcher f i ( =}}