ML20237D453
| ML20237D453 | |
| Person / Time | |
|---|---|
| Site: | Braidwood  |
| Issue date: | 08/18/1998 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20237D449 | List: |
| References | |
| NUDOCS 9808260195 | |
| Download: ML20237D453 (3) | |
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9j NUCLEAR REGULATORY COMMISSION o
's WASHINGTON. D.C. 20666 0001 k9.....,o SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 94 TO FACILITY OPERATING LICENSE NO. NPF-72 AND AMENDMENT NO. 94 TO FACILITY OPERATING LICENSE NO. NPF-77 COMMONWEALTH EDISON COMPANY BRAIDWOOD STATION. UNIT NOS.1 AND 2 DOCKET NOS. STN 50-456 AND STN 50-457
1.0 INTRODUCTION
Commonwealth Edison Company (Comed, the licensee), by letter dated January 14,1998, proposed to amend Appendix A, Technical Specifications (TS) of Facility Operating License Nos.
NPF-72 and NPF-77 for Braidwood Station, Units 1 and 2 (Braidwood). The proposed i
amendments to TS Section 3/4.8.2, " Electrical Power Systems, D.C. Sources," and its Bases support replacement of the 125 volt direct current (Vde) AT&T batteries with new Charter Power Systems, Inc. (C&D) batteries. In addition, the crosstie loading limitation is revised to reflect the increased capacity of the C&D batteries. Finally, all references to the previously installed Gou!d i
batteries are removed.
2.0 EVALUATION The batteries currently installed at Braidwood are the AT&T round cell, high specific gravity type that have exhibited a loss of capacity when discharged and then recharged. Comed plans to replace the AT&T round cell batteries on Unit 1 with new 125 Vdc C&D batteries during the upcoming refueling outage. Comed proposed changes to the Braldwood TSs to reflect the installation of C&D batteries and to remove all reference to the previously installed Gould batteries.
The staff reviewed and evaluated the proposed TS changes as follows:
(1)
All references to Gould batteries were removed from TS 3.8.2.1, Action c(1); TS 3.8.2.2, Action b(1); Surveillance Requirement (SR) 4.8.2.1.2.a,4.8.2.1.2.e,4.8.2.1.2.f; in a footnote to SR 4.8.2.1.2.b(2) and SR 4.8.2.1.2.c(3); Table 4.8-2; and the TS Bases for Section 4.8. Since the Gould batteries have all been replaced, these chsnges are acceptable.
(2)
SR 4.8.2.1.2.a.2 adds the total battery terminal float voltage of 2127.6 volts for the C&D batteries. This is the minimum vendor-recommended value for the total battery float charge (voltage range of 2.20 to 2.25 volts per cell with 58 cells). This ensures the l
effectiveness of the battery charger to float charge the batteries and is acceptab!e.
(3)
In order to comply with IEEE Standard 450-1995, " Recommended Practice for Maintenance, Testing and Replacement of Vented Lead-Acid Batteries for Stationary 9808260195 980818 PDR ADOCK 05000456 P
. - Applications," Comed proposed to revise SR 4.6.2.1.2.f to allow a performance test or a modified performance test. SR 4.8.2.1.2.f also identifies accelerated testing requirements, at least once per 12 months instead of 18 months, for a battery that is near its end ofits service life or that shows signs of degradation. This SR has a note to clarify that as long as the battery capacity is greater than 100% of the rated capacity and the battery shows no signs of degradation, the testing interval is 2 years. The changes to SR 4.8.2.1.2.f reflect the current IEEE Standard 450-1995 for testing lead acid flooded batteries, and is acceptable. The clause, "and the battery shows no signs of degradation," was not proposed by Comed, but was added by the NRC staff to make the footnote consistent with IEEE Standard 450-1995. This clause was agreed to by Comed.
(4)
Table 4.8.2, " Battery Surveillance Requirements," Notation (4) is revised to clarify that the electrolyte specific gravity is corrected for temperature only (and not level). This is consistent with the battery manufacturer's recommendations and with IEEE Standard 450-1995 (both IEEE 450 and C&D's operating instructions do not recommend correcting electrolyte specific gravity values for level, but for temperature only) and is acceptable.
(5)
Table 4.8.2 Notation (5) is revised to change the charging current from 2 amps to 3 amps to reflect the larger capacity of the C&D battery. This change is acceptable.
(6)
TS 3.8.2.1, Action c(1) and TS 3.8.2.2, Action b(1) were revised to add a crosstie loading limit (a load restriction while the battery is crosstied to opposite unit) for the C&D batteries. The limit of 200 amps for the C&D batteries ensures that the operable battery has the capacity to energize the design basis load of its associated DC bus while maintaining the limited DC loads of the crosstied, inoperable DC bus on the shutdown unit. The crosstie loading limit of 200 amps reflects the larger capacity of the C&D batteries and is acceptable.
CONCLUSION The C&D batteries are similar in design to the previously installed Gould batteries except that they have a larger capacity. The C&D batteries have a larger capacity than the currently installed AT&T batteries, are qualified for a 20-year life, will provide the same functions and be operated with the same types of operational controls as those of the installed AT&T batteries. The crosstie limit is increased to take advantage of the larger C&D battery capacity. Based on the above, the staff finds the proposed TSs acceptable.
3.0 STATE CONSULTATION
in accordance with the Commission's regulations, the Illinois State official was notified of the proposed issuance of the amendments. The State official had no comments.
4.0 EN.VIRONMENTAL CONSIDERATION The amendments change a requirement with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and change SRs.
The NRC staff has determined that the amendments involve no significant heresse in the amounts, and no significant change in the types, of any effluents that may be released offsite, l
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ 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 27758). 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 environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments.
5.0 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 co.npliance 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.
l Principal Contributor: Saba N. Saba Date: August 18, 1998 l
l