2CAN098706, Application for Amend to License NPF-6,changing Footnote to Allow Exemption for Measuring Battery Current,Increasing Required Gravity for Category a & B Limits & Reducing Total Battery Voltage from 129 to 124.7 Volts.Fee Paid
| ML20235S369 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 09/17/1987 |
| From: | Campbell J ARKANSAS POWER & LIGHT CO. |
| To: | Calvo J NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM), Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20235S372 | List: |
| References | |
| 2CAN098706, 2CAN98706, NUDOCS 8710080467 | |
| Download: ML20235S369 (10) | |
Text
-.
m.
g 1
ARKANSAS POWER & LIGHT COMPANY CAPIT0L TOWER BUILDING /P. O. B0X 551/LITTLE ROCK, ARKANSAS 72203/(501) 377 3525 September 17, 1987 T. GENE CAMPBELL Vice President Nuclear Operations 2CAN098706 US Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 i
ATTN:
Mr. Jose A. Calvo, Director Project Directorate IV Division of Reactor Projects III, IV, V and Special Projects
SUBJECT:
Aikansas Nuclear One - Unit 2 Docket No. 50-368 License No. NPF-6 Battery Technical
^!
Specification Change Request
Dear Mr. Calvo:
Thi s proposed change will af fect sections 3. 8.f., 't, 3.8. 2.4, 4.8. 2. 3.1. a, l
4.8.2.4.2, Table 4.8-2, and the Bases for 3/4.8'of the Unit 2 Technical
)
Specifications.
These changes all affect the ANO-2 station batteries.
l l
The changes to Specifications 3.8.2.3 and 3.9.2.4 consist of adding a footnote to the applicable action statement for : an inoperable battery to allow exemption from the action statement requirements for a period of time not to exceed 10 minutes when measuring batter; charguig current.
Additionally, Bases are being added to better. explain the baf tery Technical Specifications and Surveil'ances.
The proposed change to Section 4.8.2.3.1.a will reflect a change ta a bank of the ANO-2 statfon batteries.
During the fifth. refueling outage, one af l
the C0 cell battery banks was Nplaced with a 58 ceH bank.
The remaining 60 cell bank is scheduled for replacement with a 58 cell bank durine, tr.e upcoming'sOth refueling outage..This charge wil) reduce the total battery terminal voltage required durins float e.harging Orc 129 valts to 124.7 volts.
This reduction in charging volte.ge will h(lp prevent premature D.C.
equipment. failures due to high voltage during battery chargirg.. An evaluation of the change was performed and it was determined taat 'it dres not reduce the ability of the station 9a;teries to perform their function.
p %h}9 gespair 4
4 e
-._,.o u, u,-,,,...,-
- _ _ _ -. September 17, 1987 The change to section 4.8.2.4.2 is administrative and would correct a typographical error by referencing 4.8.2.3.1.a for surveillance requirements instead of 4.8.2.3.2.
Table 4.8-2 has three proposed changes.
First, to increase the required specific gravity for the Category A and B limits.
The second change would allow the battery charging current to be used in lieu of the specific gravity in determining the operability of the battery within 30 days after a service or performance discharge test.
The last change would clarify note (c) the correction for average electrolyte temperature, to be an option instead of a requirement.
The circumstances of this proposed Technical Specification amendment request are not exigent or emergency, however, this Technical Specification change would affect the methods of testing the station batteries during the upcoming refueling outage.
Therefore, we request that this proposed change be reviewed and made effective upon completion of installation of the new battery during the upcoming sixth refueling outage which is currently scheduled to begin no earlier than the first of January.
In accordance with 10CFR50.91(a)(1), AP&L has evaluated the proposed change using the criteria in 10CFR50.92(c) and has determined that this change involves no significant hazards considerations.
Also, in accordance with 10CFR50.91(b)(1) a copy of this amendment request has been sent to Ms. Greta Dicus, Director, Division of Radiation Control and Emergency Management, Arkansas Department of Health.
A check in the amount of $150 is included as a application fee in accordance with 10CFR170.12(c).
Very truly yours, ggn.,h T. Gene Campbell TGC:MCS:lw Attachments l
cc:
Ms. Greta Dicus, Director j
Division of Radiation Control l
and Emergency Management j
Arkansas Department of Health i
4815 West Markham Street
)
Little Rock, AR 72201 l
1
____J
I STATE OF ARKANSAS
)
)
SS COUNTY OF PULASKI
)
I, T. Gene Campbell, being duly sworn, subscribe to and say that I am Vice President, Nuclear Operations for Arkansas Power & Light Company; that I have full authority to execute this oath; that I have read the document numbered 2CAN098706 and know the contents thereof; and that to the best of my knowledge, information and belief the statements in it are true.
JWwYd l
T. Gene Campbel SUBSCRIBED AND SWORN T0 before me, a Notary Public in and for the County and State above named, this 3 0 day of ()L S OM 1987.
(
%Q-Notar Public My Commission Expires:
b4 N. NN
\\
s.
DESCRIPTION OF AMENDMENT REQUEST c
The first change is to Section 4.8.2.3.1.a.2 of the ANO-2 Technical l
Specifications.
This section is being revised to reflect the change from 60 cells to 58 cells and the subsequent lower battery voltage.
After this battery replacement, both Class' 1E batteries will consist of 58 cells.
Therefore, the allowance for a 60 cell battery and associated terminal voltage is being deleted.
The second change is to Section 4.8.2.4.2 which is being revised to change the referenced surveillance requirement for demonstrating operability from 4.8.2.3.2 to 4.8.2.3.1.a.
This is an administrative change to correct a typographical error.
j The third change is to Table 4.8-2.
The table is to be changed three ways.
The first change to the table increases the required value of specific gravity for the Category A and B " Limits" to reflect a nominal cell specific gravity of 1.215.
Amendment #54 to the ANO-2 Technical Specifications approved a change which lowered the original standard Technical Specification (STS) value for specific gravity.
This change was based on the fact that the original AN0-2 batteries were provided with nominal specific gravity of 1.210 instead of 1.215 on which the original STS values were based.
The new cells used in the replacement batteries are furnished by the manufacturer with a nominal specific gravity of 1.215.
Therefore, the specific gravity values are being increased back to the original STS values.
The second change to the table adds a note which will allow the battery charging current to be used in lieu nf the specific gravity parameter of the Category B " Limits" in determining the operability of the battery within thirty (30) days after either a service or performance discharge test.
The station batteries are presently subjected to a service discharge test once every 18 months and a performance discharge test once every 60 months to comply with the Technical Specification requirements.
At the completion of a service or performance discharge test, the test procedure requires a quarterly surveillance to demonstrate the operability of the battery.
This procedure uses the Category B limits of Table 4.8-2 as the acceptance criteria.
Although the battery is fully charged after a discharge test and capable of performing its safety function, it cannot be declared operable until the specific gravity limits are satisfied.
To avoid the usual delay associated with the specific gravity diffusion process, the service discharge test procedure mandates mixing of the electrolyte in each cell prior to taking tM specific gravity readings.
This mixing process increases the risk of cell electrolyte contamination and spillage which could result in shortening the life of the battery, damage to equipment and injury to personnel.
Also, the delay in declaring the battery operable causes a delay in performing scheduled maintenance and test to the other battery.
The specific gravity drops during a discharge approaching a value of 1.00.
On the subsequent recharge, the measured specific gravity of the cells lags behind the true specific gravity.
This is caused by the release of strong,
i heavy acid from the plates during the recharge which falls toward the bottom of the cell where it gradually diffuses through the solution.
Depending on the depth of discharge and the recharge voltage, diffusion of the acid through the electrolyte may take several weeks.
Due to the time required for the diffusion process, the specific gravity parameter does not accurately reflect the battery's state of charge immediately af ter recharging.
Therefore, the specific gravity parameter is not an accurate indication of the operability of the battery during this time.
The battery charging current is a more accurate indicator of the battery's state of charge and is currently utilized by the Category A Limits.
Using the battery charging current indicator resolves the problems associated with mixing electrolyte and delaying battery operability after scheduled discharge tests.
This change in testing is supported by IEEE 450-1980, section 4.5 and Appendix A, Part A1.
The third change to table 4.8-2 is a revision to note (c) to clarify that a voltage correction for average electrolyte temperature is an option not a mandatory requirement.
The purpose of the cell voltage correction for temperature is to determine if an equalize charge is necessary when cell temperatures vary.
The temperature correction factor should only be applied to cells in a battery which have both a higher than average temperature and a lower cell voltage.
The voltage correction is allowed but not mandated by IEEE 450-1980 and is not recommended for use where all cells are at approximately the same temperature or to routinely adjust the cell voltage limits for variations in cell temperatures.
The last change is the addition of information to the bases of the Technical Specifications.
This additional information involves the second and third changes to table 4.8-2.
The change which would allow the battery charging current to be used in lieu of the specific gravity requires the use of a battery charging current metering system which can accurately measure the small charging current to the battery.
The operational procedure of the metering system requires opening the main battery disconnect switch to obtain the current reading.
The time required to complete the reading and place the disconnect switch back in service should be less than ten minutes.
During the time the disconnect switch is open, the battery charger continues to charge the battery through the metering circuit and provide power to the normal DC loads.
However, the battery is not considered operable during this time because it cannot perform an emergency duty cycle discharge with the disconnect switch open.
Although the battery is technically inoperable the battery charger is charging the battery er.d providing power to all associated DC loads as it would during normal operation.
Figure-1 is a simplified sketch of the metering circuit.
The proposed change to the Bases and addition of a footnote to Technical Specifications 3.8.2.3 and 3.8.2.4 would clarify the allowable use of this metering system.
During conditions where both battery banks are required to be operable, opening of the disconnect switch is restricted to one battery at a time.
The other change to the Bases explains the correction of cell voltage when a temperature difference exists between cells.
CALCULATION NO.
CALCULATION SHEET FIGURE-1 0F ARKANSAS POWER 8 LIGHT 2CAN098706 PAGE OF 2bl2
--l l
l I ED5E
_ N_ o T E I n
n
<\\ ([20ALTYE4)
~
i 6-i
-II r
i ED_32.
ED4e
~
i
=_-
i
- p.
- f
- \\ f'
~
"I o
oI o4
.)
I w
{
1 sur i
l
" " ~
4 9
9 >
l O-20 A
(!.
2bOL 1
2DlP_- BATTERY tBTE l : 807H PEE 5 oFEFEAMP_
2b57_- NON-A 0To C.JPhnT BREAKER Shout 4 Fbe C.LAPJTV Eb42-FUSE / RELAY FAHEL NLM2: THIS IS A PARTIAL SKETCH 2bo? - bl. SHITCHGEAR OF bC. SYSTEM Tb SHOW P_bS?_- EATTERY c_HAR&ER.
M E hs;0 R E M D J T 3 1 3 7 & 1 l
REV. l l
BY CHKD APP'D
l 4
J BASES FOR PROPOSED NO SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION As this proposed change consists of several parts each part will have a separate significant hazards consideration determination.
PART 1 The proposed change to Section 4.8.2.3.1.a does not involve a significant hazards consideration because operation of Arkansas Nuclear One Unit 2 in accordance with this change would not:
(1) Involve a significant increase in the probability or consequences of an accident previously analyzed.
The proposed change to the station batteries would replace the 60 cell l
battery bank with a 58 cell battery bank.
This change does not reduce the ability of the station battery banks, individually or as a whole, to perform their design function.
The additional proposed change to Section 4.8.2.3 allows a 10 minute period in which the battery may be taken off line for measuring battery charging current.
As indicated in the Safety Analysis Report Table 8.3-11 (125-Volt DC Engineered Safety Feature System Single Failure Analysis), in the event of loss of one dc bus, the redundant bus will supply control power to the ESF load of the corresponding channel.
Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously analyzed.
(2) Create the possibility of a new or different kind of accident from any previously analyzed.
l The specifications and design of the replacement batteries are equal or exceed the original batteries.
In addition, all interfacing equipment and systems remain the same with no changes.
Therefore, this change does not introduce the possibility of a new or different kind of accident.
(3) Involve a significant reduction in the margin of safety.
An evaluation of this change has shown that the reduction in the number of battery cells does not reduce the ability of the station batteries to perform their design function.
This change does decrease the I
required equalizing voltage and thus decreases the probability of premature failure of normally energized D.C. equipment.
Thus, there is no significant change in the margin of safety.
I Based upon the above, it can be seen that the proposed change does not l
involve a significant hazards consideration.
The Commission has provided guidance concerning the application of these standards by providing examples.
The proposed amendment matches example (ix).
"A repair or replacement of a major component or system important to safety, if the following conditions are met:
l
(1) The repair or replacement process involves practices which have been successfully implemented at least once on similar components or systems elsewhere in the nuclear industry or in other industries, and does not involve a significant increase in the probability or consequences of an accident previously evaluated or create the possibility of a new or different kind of accident from any accident previously evaluated; and (2) The repaired or replacement component or system does not result in a significant change in its safety function or a significant reduction in any safety limit (or limiting condition of operation) associated with the component or system."
pART 2 The proposed change to Section 4.8.2.4.2 does not involve a significant hazards consideration because operation of Arkansas Nuclear One Unit 2 in accordance with this change would not:
(1) Involve a significant increase in the probability or consequences of an accident previously analyzed.
The proposed change would not increase the probability or consequences of any accident previously evaluated since this administration change does not provide any relief from the requirements of the Technical Specifications, or change the intended operation or administrative requirements of the plant or its design bases.
(2) Create the possibility of a new or different kind of accident from any l
previously analyzed.
The proposed change would not create the possibility of a new or different kind of accident from any previously analyzed since this administrative change does not adversely affect any components or systems which contribute to the safety of the plant.
(3) Involve a significant reduction in the margin of safety.
The proposed change would not involve significant reduction in the margin of safety since this change corrects an error but has no effect on any plant safety parameters, accident mitigation capabilities or procedures, Based upon the above, it can be seen that the proposed change does not i
involve a significant hazards consideration.
The Commission has provided guidance concerning the application of these standards by providing examples.
The proposed amendment is most closely encompassed by example (i):
" purely administrative changes to the Technical Specifications."
\\
4 PART 3 The proposed change to the specific gravity limits of Table 4.8-2 does not involve a significant hazards consideration because operation of Arkansas Nuclear One Unit 2 in accordance with this change would not:
(1) Involve a significant increase in the probability or consequences of an accident previously analyzed.
The proposed changes to the specific gravity limits are more restrictive than the current limits.
Therefore, the proposed changes do not involve a significant increase in the probability or consequences of an accident previously analyzed.
(2) Create the possibility of a new or different kind of accident from any previously analyzed.
No new possibility for an accident is introduced by modifying the specifications for the surveillance testing as the new limits are more i
restrictive than the current limits for battery cell specific gravity to reflect the use of new battery cells.
(3)
Involve a significant reduction in the margin of safety.
The existing Technical Specification, operability and surveillance requirements are not reduced by the proposed changes, thus no margins of safety are reduced.
Based upon the above, it can be seen that the proposed change does not involve a significant hazards consideration.
The Commission has provided guidance concerning the application of these standards by providing examples.
The proposed amendment most closely matches example (ii):
"A change that constitutes an additional limitation, restriction, or control not presently included in the technical specifications, e.g., E more stringent surveillance requirement."
PART 4 The proposed addition of note (d) to Table 4.8-2, the addition of footnotes to specifications 3.8.2.3 and 3.8.2.4 and the corresponding addition to the Bases of the Technical Specifications do not involve a significant hazards consideration because the operation of Arkansas Nuclear One Unit 2 in accordance with these changes would not:
(1) Involve a significant increase in the probability or consequences of an accident previously analyzed.
The proposed change to the method of assuring battery operability maintains conservative restrictions on battery operability and meets current industry standards.
Therefore, the change does not involve a significant increase in the probability or consequences of an accident previously analyzed.
(2) Create the possibility of a new or different kind of accident from any previously analyzed.
The new method of surveillance for battery operability provides the same degree of assurance of operability as the previous surveillance method.
Therefore, the possibility of a new or different kind of accident from any previously analyzed is not created.
(3) Involve a significant reduction in the margin of safety.
The alternate method of determining the battery's charge by observing the electrical current provides the same degree of confidence the batteries can perform their safety function as does the primary method.
Therefore, the station batteries have the same capabilities to mitigate and/or prevent accidents as they did prior to the change in surveillance methods.
Based upon the above it can be seen that the proposed changes do not involve a significant hazards consideration.
PART 5 The proposed change to note (c) of Table 4.8-2 and the corresponding addition to the Bases of the Technical Specifications do not involve a significant hazards consideration because the operation of Arkansas Nuclear One Unit 2 in accordance with these changes would not:
(1) Involve a significant increase in the probability or consequences of an accident previously analyzed.
The proposed change is for clarification only and does not increase the probability or consequences of an accident previously analyzed.
(2) Create the possibility of a new or different kind of accident from any previously analyzed.
The proposed changes do not affect the operability of the station batteries and do not create the possibility of a new or different kind of accident from any previously analyzed.
3)
Involve a significant reduction in the margin of safety.
This change is a clarification of current surveillance requirements and does not involve a reduction in the margin of safety.
Based upon the above it can be seen that the proposed changes do not involve a significant hazards consideration.
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ _ - _ -