ML20116N645
| ML20116N645 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 04/26/1985 |
| From: | NEBRASKA PUBLIC POWER DISTRICT |
| To: | |
| Shared Package | |
| ML20116N627 | List: |
| References | |
| NUDOCS 8505070298 | |
| Download: ML20116N645 (8) | |
Text
k,1 I y
-Attachmsnt i 1
EP Revised Technical Specifications for 125/250 Volt D-C Station Batteries Revised Pages:
194 195 196 197 198
.A recent NRC inspection (84-26) focused on the 125/250 volt D-C station batteries resulted in the identification-of Severity Level III violations and subsequent. civil penalty.- The NRC observed that the District had apparently
-failed to demonstrate-the operability of the station batteries.
A thorough study of this issue was conducted by the District in order to correct any
-departure from NRC requirements.
The study' included a review of pertinent NRC-endorsed and generated documents including, but not limited to, IEEE Standard 450-1980; IEEE Standard 308-1978; Regulatory Guides 1.129, 1.118, and-1.32; GE standard Technical Specifications for BWR/4 (NUREG-0123); and Standard Review Plan (NUREG-0800); as well as applic'able sections of the CNS
- Technical Specifications, USAR, engineering procedures, and the battery manufacturer's recommendations.
Nebraska Public-Power District requests a revision to the Technical Specifications which will incorporate changes to the station battery surveillance requirements and bases in order to:
- 1) improve the demonstration
~
of the unit' battery system operability, 2) incorporate appropriate guidance from the various ' aforementicned NRC endorsed industry standards, regulatory guides, etc., and battery manufacturer's recommendations.
In order to clarify the difference between existing and proposed Technical Specifications, a point-by-point explanation follows:
1.
The absolute value for the total battery terminal voltage Q105 volts for
,the 125-volt batteries, >212 volts for the 225-volt batteries) was specified for the weekly. surveillance addressing the measurement and recording of total battery voltage.
These voltage values were obtain'ed
-as described in the -final-paragraph of revised bases page 198. '
2.
Measurement and logging of electrolyte level for each pilot cell and a i
specified acceptable level range was added to the Tweekly surveillance i
items.
l.
[
3.
Temperature and electrolyte level correction was'added to the pilot cell voltage.and specific ; gravity measurement surveillances, as well as the i
requirement that-these-parameters meet the~ manufacturer's recommendations.--
+
i --
4 The ne'asurement tolerance of 0.1 volt was deleted since it was deemed to l
be more appropriately addressed in the revised CNS surveillance procedure.
5.
Industry-accepted term " Battery Service Test" was used in lieu of " Rated Load-Discharge Test" in' describing the once per-operating-cycle battery j
capacity surveillance..
3
[
L in asm ag.;-
~
F l
{
6.
A tolerance band of tS*F was specified for the acceptable temperature differential between a representative sample of battery cells.
7.
A performance discharge test to verify the station battery capacity to be
.at least 85 percent of the manufacturer's rating was added as a five-year surveillance item.
Each of the-above changes were introduced to improve the overall demonstration
'of battery operability and provide for improved assurance of verification that the CNS= station batteries fully satisfy their design function, utilizing the aforementioned documents as guidance.
It is the District's position that these changes will improve plant safety, hence there is no loss of safety function or any reduction in the degree of protection provided public health and safety.
Evaluation of this Revision with Respect to 10CFR50.92 A.
The enclosed Technical Specification change is judged to involve no significant hazards based upon the following:
1.
Does the proposed license amendment involve a significant increase in the probability or consequences of an accident previously evaluated.
Evaluation:
The proposed change will result in improved surveillance requirements and related surveillance procedures.
No changes to existing equipment are being introduced and no changes are being
'made to surveillances or procedures which will affect the probability or consequences of an accident previously evaluated.
2.
Does the proposed license amendment create the possibility for a new or different kind of accident from any accident previously evaluated?
Evaluation:
The proposed changes does not introduce any new mode of operation, and the possibility of an accident of a different type than analyzed in the FSAR would not result from the change.
3.
Does the proposed amendment involve a significant reduction in a margin of safety?
Evaluation:
The proposed change does not change existing facility equipment.
The proposed change will, however, change existing surveillances and procedures, making them more stringent than previously required.
The additional surveillance requirements use NRC-endorsed or generated standards as acceptance criteria and are being introduced to increase demonstrated operability of the station batteries. This will not involve a significant reduction in the margin of safety.
T:
,5 1
B. :
Additional basis for proposed no significant hazards consideration determination:
s The' Commission has provided guidance concerning the application of the standards for making a no significant hazards consideration determination by providing certain examples (48FR14870).. The-examples include "(11) A change that constitutes an additional limitation, restriction, or control not presently included in the Technical Specifications:
for example, a more stringent surveillance requirement."
It is the District's belief that the proposed change is encompassed by the above example.
L.
..J
LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS 3.9.A 4.9.A.2 (cont'd) 2.
At least one diesel generator During the monthly generator test the shall be operable during fuel diesel generator starting air compres-handling operations. This one sor shall be checked for operation and diesel shall be capable of its ability to recharge air receivers.
supplying power to an operable The operation of the diesel fuel oil Standby Gas Treatment System, transfer pumps and fuel oil day tank level switches shall be demonstrated, and the diesel starting time to reach rated voltage and frequency shall be logged.
b.
Once'every 18 months the condition under which the diesel generator is required will be simulated and a test conducted to demonstrate that it will start and accept the emergency load within the specified' time sequence.
The results shall be logged.
c.
Specification 4.9.A.2.c deleted.
d.
Once a month the quantity of. diesel fuel available shall be logged.
1 e.
Every three months and upon delivery a sample of diesel fuel shall be checked for quality.
The quality shall be within the ace'eptable limits specified in Table 1 of ASTM D975-68 for Nos. 1D or 2D and logged, f
f.
Each diesel generator shall be given an annual inspection in accordance with instructions' based on the manu-facturer's recome:ndations.
3.
125 VDC Unit Batteries a.
Every week, the following parameters shall be verified.
The actual values shall be measured and logged:
1.
The total battery terminal vol-tage is equal to or greater than 105 volts, 2.
The electrolyte level of each pilot cell is between the min-imum and maximum level indica-tion marks.
-194-
+ -..
LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REOUIREMENTS' 3.9.A
.4.9.A (cont'd.)
3.
The pilot ce?.1 voltage and spe-cific gravity, corrected for 77'F and electrolyte level, are in accordance with the manufac-turer's recommendations.
b.
Every quarter, the following para-meters shall be verified.
The actual values shall be measured and logged:
1.
The electrolyte level of each connected cell is between the minimum and maximum level in-dication marks.
2.
For each connected cell, the voltage and specific gravity, corrected for 77'F and electro-lyte level, are in accordance with the manufacturer's recom-B. Operation with Inoperable Equipment mendations.
- 1. Whenever.the reactor is in Run Mode or 3.
The electrolyte temperatures Startup Mode with the reactor not in a in a representative sample of Cold Condition, the availability of cells, consisting of at least electric power shall be as specified every sixth cell, are within in 3.9.A.1, except as specified in 25'F.
3.9.B.1.
c.
Once each operating cycle, the 125
- a. Incoming Power VDC batteries shall be subjected to a battery service test.
- 1. From and after the date incoming power is not available from a startup or emer-d.
At least once each 5 years, the gency transformer, continued reactor battery capacity shall be verified operation is permissible under this to be at least 85% of the manufac-condition for seven days. At the end turer's rating when subjected to a of this period, provided the second performance discharge test.
This source of incoming power has not been performance discharge test shall be made immediately available, the NRC performed subsequent to the satis-muut be notified of cl3 avant and the factory completion of the required plan to restore this secons source.
battery service test.
During this period, the two diesel generators and associated critical buses must be demonstrated to be operable.
- 2. From and after the date that incoming power is not available from both start-up and emergency transformers (i.e.,
both failed), continued operation is permissible, provided the two diesel generators and associated critical buses are demonstrated to be
-195-
_.~
LIMITING CONDITIONS FOR OPERATION I SURVEILLANCE REQUIREMENTS r,
3.9.B (cont'd.)
'4.9.A.4 250 VDC Unit Batteries operable, all core and containment a.
Every week, the following parameters cooling systems are operable, reactor shall be verified. The actual values power level is reduced to 25% of the shall be measured and logged:
rated and NRC is notified within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of the situation, the precau-1.
The total battery terminal
.tions to be taken during this period voltage shall be equal to cr and the plans for prompt restora-greater than 212 volts, tion of. incoming power.
s 2.
The electrolyte level of each b.
Diesel Generators pilot cell is between the minimum and maximum level 1.
From and after the date that one of indication marks, the diesel generators or an associ-4 ated critical bus is made or found 3.
The pilot cell voltage and to be inoperable for any reason, specific gravity, corrected continued reactor operation is per-to 77*F and electrolyte level, missible in a.ccordance with Speci-are in accordance with the fication 3.5.F.1 if Specification manufacturer's recommenda-3.9.A.1 is satisfied.
- tions, 7
i 2.
Frca ard aft 9r the date that.both b.
Every quarter, the following par-diesel honorators are made or found aseters shall be verified.
The to be inoperable for any reason, actual values shall be measured continued reactor operation is per-and logged
.missible only during the succeeding 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> in accordance with Speci-1.
The electrolyte level of each fication 3.5.F.2 if Specification connected cell is between the 3.9.A.1 is satisified, minimum and maximum level indication marks.
3.
From and after the date that one of the diesel generators or associated 2.
For each connected cell, the f
critical buses and either the emer-voltage and specific gravity, i
gency or startup transformer power corrected for 77*F and electro-t source are made or found to be in-lyte level, are in accordance operable for any reason, continued with the manufacturer's recom-l reactor operation is permissible in mandations.
accordance with Specification 3.5.F.1, provided the other off-site source, 3.
The electrolyte temperatures j
startup transformer or emergency in a representative sample of transformer is available and cells, consisting of at least 1
capable of automatically supplying every sixth cell, are within power to the 4160V critical buses and 15' F.
the NRC is notified within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of the occurrence and the plans for c.
Once each operating cycle, the 250 restoration of the inoperable compo-VDC batteries shall be subjected to i
nents.
a battery service test.
I
-196-
- .c
. LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS
?3.9.B.5.(cont'd.)
4.9.A.4 (cont'd) f
~
c.
DC Power' d.
At least once each 5 years, the bat-i tery-capacity shall be verified to
-1.
From and after the date that one of be at least 85% of the manufacturer's t
the 125 or 250 volt battery systems rating when subjected to a performance is mde or found to be inoperable discharge test. This performance dis-for any reason, continued reactor charge test shall be performed subse-operation-is permissible during the quent to the-satisfactory completion
- succeeding ten days within electri-of the required battery service test.
cal safety considerations, provided 4
repair work is initiated in the most 4
Power Monitoring System for RPS Systes expeditious manner to return the failed component to an operable The above specified RPS power monitor-state, and Specifications 3.5.A.5 ing system instrumentation shall be and'3.5.F are satisfied.
The NRC determined operable:
shall be notified within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />
.of the situation, the precautions a.
At least once per operating cycle to be taken during this period and by demonstrating the operability the plans to return the failed of ovar-voltage, under-voltage j
components to an operable state, and under-frequency protective i
instrumentation by performance of d.
RPS/MG Sets a channel calibration including I
simulated automatic actuation of
}
1.
With one RPS electric power monitor-the protective relays, tripping i
ing channel for an inservice RPS MG logic and output circuit breakers i
set or alternate power supply inop-and verifying the following set-j erable, restore'the inoperable chan-points.
nel to operable status within 72-i hours or remove the associated RPS 1.
Over-voltage < 132 VAC, with MG set or alternate power supply time delay <,2 sec.
l l
from service.
j 2.
Under-voltage > 108 VAC, with i
~
2.
With both RPS electric power moni-time delay ~< 2 sec.
f toring channels for an inservice RPS 1
MG set or alternate power supply in-3.
Under-frequency > 57 Hz with operable, restore at least one to time delay ~< 2 sec.
l operable status within 30 minutes or
}
remove the associated RPS MG set or alternate power supply from service.
I i
i 4
i i
i i
i
-197-
p o., u *,
3.9 BASES The general objective of this Specification is to assure an adequate source of electrical power to operate the auxiliaries during plant operation, to operate facilities to cool and lubricate the plant during shutdown and to operate the engineered safeguards following the accident.
There are three sources of ac electrical energy available; namely, the startup transformer, the emergency transformer and two diesel generators.
The de supply is required for switch gear and engineered safety feature systems.
This supply consists of two 125V DC and two 250V DC batteries and their related chargers.
Specification 3.9.A states the required availability of ac and de power; i.e., active off-site ac sources and the required amount of on-site ac and de sources.
Auxiliary power for CNS is supplied from the startup transformer and the normal trans fo rmer. Both of these transformers are sized to carry 100% of the station auxiliary load.
The emergency transformer is about one third the size of these two transformers and is equal in size to both emergency diesel generators.
The startup transformer and the emergency transformers are the offsite power sources. Their voltage is monitored by undervoltage relays which provide low voltage protection for the emergency buses.
Whenever the voltage setpoint and time delay limit for the undervoltage relays have been exceeded, the emergency buses are automatically disconnected from the offsite power source.
If the startup or emergency transformer is lost, the unit can continue to operate since the unit auxiliary transformer is in service, and the emergency or startup transformer and the diesels are available.
If both the startup and emergency transformers become inoperable, the power level must be reduced to a value where by the unit can safely reject the load and continue to supply auxiliary electric power to the station.
In the normal mode of operation, the startup and emergency transformers are energized and two diesel generators are operable. One diesel generator may be allowed out of service based on the availability of power from the startup transformer and the fact that one diesel generator carries sufficient engineered safeguards equipment to cover all breakers. With the startup transformer and one diesel generator out of service, the off site transmission line corresponding to the emergency transformer must be available. Upon the loss of one on-site and one off-site power source, power would be available from the other immediate off-site power source and the two operable on-site diesels to carry sufficient engineered safeguards equipment to cover all breaks.
In addition to these two power sources, removal of the Isolated Phase Bus " quick" disconnect links would allow backfeed of power through the main transformer to the unit auxiliary transformer and provide power to carry the full station auxiliary load.
The time required to perform this operation is comparable to the time the reactor could remain on RCIC operation before controlled depressurization need be initiated.
A battery charger is supplied with each of the 125/250 Volt batteries. The 125 Volt battery system shall have a minimum of 105 Volts at the battery terminals to be considered operable. The 250 Volt battery system shall have a minimum of 212 Volts at the battery terminals to be considered operable.
These values are based on a minimum of 1.75 Volts per cell (each 250 Volt battery has 121 cells and each 125 Volt battery has 60 cells).
-198-
~
.