ML20211Q139
| ML20211Q139 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 10/08/1997 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20211Q133 | List: |
| References | |
| NUDOCS 9710220129 | |
| Download: ML20211Q139 (4) | |
Text
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[jsp % g UNITED STATES y
j NUCLEAR REGULATORY COMMISSION t
WASHINGTON, D.C. 30666 4 001
...../
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR RE*CTOR REGULATION RELATED TO AMENDMENT NOS.123 AND 88 TO FACILITY OPERATING LICENSE NOS. NPF-39 AND NPF-85 PHILADELPHIA ELECTRIC COMPANY LIMERICK GENERATING STATION. UNITS 1 AND 2 DOCKET NOS. 50-352 AND 50-353
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1.0 INTRODUCTION
By letter dated April 9,1997, the Philadelphia Electric Company (PEC0, the licensee) submitted a request for changes to the Limerick Generating Station, Units 1 and 2, Technical Specifications (TSs).
The requested changes would revise the TSs to clarify existing battery-specific gravity requirements,.
delete the requirement to correct specific gravity values based on electrelyte level, and allow the use of charging current measurements to verify the battery's state of charge.
2.0 EVALUATION PECO requested 13 changes that will revise TS Table 4.8.2.1-1, " Battery Surveillance Requirements," and the TS Bases Section 3/4 8.2, "D.C. Sources,"
related to TS Table 4.8.2.1-1.
The following is a detailed listing of the
=
proposed changes:
Table 4.8.2.1-1:
1.
The word "AND" is added between the specific gravity, Category B limits and allowable value par ameters.
The licensee has stated that Limerick TS Table 4.8.2.1-1 specific gravity, Category B limits and the. allowable values are implied to be "AND" statements.
Therefore, addina the "AND" between the specific gravity, Category B limits and allowable valee parameters will only clarify the meaning of the Limerick TS. Additionally, this change is consistent with NUREG-1433, " Standard Technical Specifications, General Electric Plants, BWR/4," which currently has an "AND" between the specific gravity, Category B limits and the allowable value parameters, k, 0 1
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. -2.
The specific gravity, Category B allowable value for each connected cell is revised to replace the existing statement describing the value with an equivalent discrete value of 1.170.
TS Table 4.8.2.1-1 currently states the Category B, specific gravity allowable values as "Not more than 0.020 below the average of all connected cells."
This requirement ensures that the effect of a highly charged or new cell does not mask overall degradation of the battery. The licensee is proposing to replace the current wording in the TS with a discrete value c# 1 1.170. The discrete value of 1.170 is 0.020 below the average allowable specific gravity of 1.190 currently listed in the Limerick TS. Therefore, the licensee states that the change only clarifies the TS and does not change the intent of the surveillance requirement.
3.
Note number 6, "Or battery charging current is less than one amperes when on float charge" will also be applied to the specific gravity, Category B allowable value for each connected cell.
The licensee is proposing to use the charging current as an alternative to specific gravity measurements to verify the battery's state of charge. The proposed change will not eliminate specific gravity measurements but will provide more time to allow all cell parameters to rise above Category B limits. The licensee states that specific gravity measurements may not be accurate after water is added to the battery, at times when the battery is being charged, and periods immediately following battery charging. The practice of using the charging current to determine the state of charge of the battery is an acceptable alternative and is discussed in the Institute of Electrical and Ele:tronics Engineers' (IEEE) Standard (Std.) 450.
IEEE Std. 450states that the pattern of charging delivered by a conventional voltage-regulated charger after a discharge is the most accurate method for-determining the state of charge. As the cells approach full charge, the battery voltage rises to approach the output voltage of the charger, and the charging current decreases.
When the charging current has stabilized at the charging voltage, the battery is charged, even though specific gravities have not stabilized.
Additionally, NUREG-1433 states that a stabilized charger current is an acceptable alternative to specific gravity measurement for determining the state of charge of the designated pilot cell. The justification for this statement is that specific gravity gradients that are produced during the recharging process delay the stabilization of the specific gravity for up to several days.
A r
.3-4.
Note number 5, which st'ates,'" Corrected for average: electrolyte '
temperature.of-77'F and full level," will be modified to delete the requirement for full level.
-The licensee is proposing to remove the requirement for level correction when
- monitoring battery-specific gravity. 1The licensee states that current manufacturer's recommendations for monitoring specific gravity no longer-require level correction. An increase in the specific gravity is normal with a decrease-in water level because the electrolyte becomes more concentrated.
The manufacturer states tha the battery performance is not affected by
. changes in-electrolyte level as.long-as the change in level is reasonable (i.e., between the:high1and low level marks on the battery). Additionally, IEEE 5td. 450 states that if the electrolyte level is-between the high.and low level-marks and. the temperature-corrected specific gravity of the electrolyte is within the manufacturer's-nominal specific gravity range, it is not necessary to. correct the specific gravity of the battery for electrolyte level. -The current lTSs at Limerick do require that the battery electrolyte
. level be maintained between the high and low level: marks.
~ TS Bases-Section B 3/4 8-2:
1.
TS Bases Section B 3/4 8-2 is revised-to reflect the-above proposed changes-regarding TS Table 4.8.2.1-1.
The staff has reviewed the proposed changes and concludes that they are either editorial and/or consistent with-IEEE Std. 450 and NUREG-1433. Therefore, the staff finds the pnposed changes by the licensee acceptable.
3.0 STATE CONSULTATION
I In accordance with the Commission's regulations, the Pennsylvania State official was notified of the-proposed issuance of the amendments.
official had no cremments.
The-State-4.0. ENVIRONMENTAL CONSIDERATION 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. 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 (62 FR 30643). 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 Comission 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 Comission'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 Contributors:
M. Pratt
- 5. Saba Date: October 8, 1997
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