ML20113H308
| ML20113H308 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 07/23/1992 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20113H307 | List: |
| References | |
| NUDOCS 9207290175 | |
| Download: ML20113H308 (3) | |
Text
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- h UNITED STATES 3,)#(
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'59 SAFETY EVALVATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING APEN0 MENT NO.146 TO FACIllTY OPERATING LICENSE NO. DPR-72 FLORIDA POWLR CORPORATION. ET AL, CRYSTAL RIVER UNIT NO. 3 NUCLEAR GENERATIM PLANT QQCKET NO. 50-302 1.0 INTR 00VCTION By letter dated February 13, 1992, Florida Power Corporation (FPC, the licensee) requested revisions to Technical Specifications (TS) Sections 3.1.2.9 and 3.5.4 and TS Bases 3/4.1.2 and 3/4.5.4 of Facility Operating
'icense No. DPR-72 for the Crystal River Unit 3 (CR-3) Nuclear Generating Plant.
The proposed revision changes the upp
- limit for boron concentration in the borated water storage tank (BWST) from the present value of 2,450 ppm to 3,000 ppm. The lower concentration limit muld remain unchanged.
This change is c edicated on another proposed awndment that requests approval for the use cT trisodium phosphate dodecahydrate (TSP-C) in place of sodium hydroxide as the post-LOCA buffering agent.
2.0 BACKGROUND
The CR-3 refueling canal water and the reactor coolant system (RCS) boron concentrations are typically maintained in the range of 2,450 to 3,000 ppm.
After refueling, under the present TS, the licensee would have to reduce the boron concentration to less than or equal to 2,450 ppm before entering Mode 4.
The proposed increase in allowable upper limit BWST boron concentration would permit direct transfer of refueling canal water to the BWST without deboration and reduce the outage time.
3.0 EVALVATION The BWST boron concentration range presently permitted for CR-3 is between 2,270 and 2,450 ppm.
The minimum BWST boron concentration is not being changed by this amendment.
Only the upper limit is being increased to 3,000 ppm.
The minimum BW5T baron concentration assures a subcritical reactor in the cold condition following the mixing of the BWST and ".LS water volumes.
The maximum BWST boron concentration assures that 'oron precipitation does not o
occur during the long-term cooling period associated with the post-LOCA conditions. Also, the limiting range in BWST boron concentration assures a pH 9207290175 920723 PDR ADOCK 05000302 p
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2 of at least--7.0 for the solution in the reactor building emergency sump for the post-LOCA scenario.
The acceptable pH range will minimize the evolution of iodine and the effects of corrosion on reactor building components.
The licensee has stated that the boron concentration necessary to possibly create a precipitation condition is-40,000 ppm at a temperature of 212 *F.
During post-LOCA conditions, the boron concentration in the reactor vessel would not exceed 10,000 ppm under the worst-case scenario.
Therefore, the licensee has concluded that the increase for the upper limit of the BWST boron concentration to 3,000 ppm would be acceptable.
Further, the licensee has evaluated the effects of combining a boron concentration of 3,000 ppm and trisodium phosphate dodecahydrate (1600 ppm) for the RCS/BWST solution in the reactor building emergency sump.
The evaluation has indicated that the pH of the solution would increase to an acceptable level of at least 7.0.
The staff has evaluated the proposed TS change and related justifications considering boron precipitation and a pH level of at least 7.0.
The staff finds that the-proposed increase to 3,000 ppm for the upper limit of the boron concentratiori is acceptable based on empirical data used in the evaluation and approval of similar TS changes for other operating power plants.
This data establishes the pH level for specific combinations of TSP-C and boric acid concentrations, and determines the minimum temperature (*F) that would assure the solubility of boric acid in water.
The results agree with the licensee's conclusions that boron orecinitation is precluded for the proposed concentrations of boric acid and tsp-C, and that the pH level can be increased to a level above 7.0.
4.0 STATE CONSULTATION
Based upon the written notice of the proposed amendment, the Florida State official had no comments.
5.0 ENVIRONMENTAL-CONSIDERATION This amendment changes a requirement with respect to installation or use of a facility component lccated 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 chan9e 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. Tne Commission has previously issued a proposed finding that this amendment involves no significant hazards consideration and there has been no public comment-on such finding (57 FR 11109). Accordirgly, this 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 this amendment.
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6,0 (ONCLUSION The Commission has concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health snd safety of the pablic wil' not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public, Principal Cor.tributur:
F. Rinaldi Date:
July 23,1992 i
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