ML20238E675
| ML20238E675 | |
| Person / Time | |
|---|---|
| Site: | Catawba  |
| Issue date: | 12/28/1987 |
| From: | Tucker H DUKE POWER CO. |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| NUDOCS 8801050284 | |
| Download: ML20238E675 (8) | |
Text
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DUKE POWER GOMPANY P.O. DOJC 3318D CIIAILLOTTE, N.O. 28242 HALU. TUCKER TE12 PHONE vms eneminswr (704) 07&4M1 ptmtman reopocrion i
December 28, 1987 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D. C. 20555
Subject:
Catawba Nuclear Station Docket Nos. 50-413 and 50-414 IE Report 50-413/87-30 RII:PKV/MSL
Dear Sir:
Please find attached revised responses to the Violations 414/87-30-01 and 413,414/87-30-02 as requested by a letter from Dr. J. Nelson Grace on December 10, 1987.
Very truly yours, O & AK Hal B. Tucker LTB/1160/sbn I
Attachment xc:
Dr. J. Nelson Grace, Regional Administrator U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 I
Mr. P. K. Van Doorn NRC Resident Inspector Catawba Nuclear Station h
i
(
)
871228 l
8801050284 ADOCK0500g3 DR
DUKE POWER COMPANY.
RESPONSE TO VIOLATION 413, 414/87-30-01 1
Technical Specification T.S.
2.2.1 requires that the. Reactor 1
Trip System Instrumentation and Interlocks Setpoints shall be set consistent with the Trip Setpoint values shown in
. With.a Reactor Trip System Instrumentation or Table 2.2-1.
Interlock Setpoint less conservative than the value shown in i
the Allowable Values column of Table 2.2-1, adjust the I
l Setpoint consistent with the' Trip Setpoint Value and L
determine within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> that Equation 2.2-1 was satisfied I
for the affected channel.
contrary to the above, on April 29, 1987, with all four channels of Power Range Neutron Flux Trip Setpoints less conservative than the Allowable Value of Table 2.2-1, the licensee used incorrect values for Z and S in Equation 2.2-1 to determine that Equation 2.2-1 was satisfied and to conclude that the event was within the safety analysis.
Consequently, determination that Equation 2.2-1 was satisfied was not performed within the 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> specified by the Tech Spec Action Statement.
RESPONSE
1.
Admission or Denial of Violation Duke Power Company admits the violation.
2.
Reasons for Violation if Admitted Technical Specification 2.2.1 requires that the Power Range 9IS High Flux Reactor Trip setpoints be more conservative than 111.1% of Rated Thermal Power as evaluated by equation 2.2-1:
s Z + R + S < TA Where:
Z = 4.56 (from Table 2.2-1)
R = Determined Rack Drift Error S = 0.0 (from Table 2.2-2)
TA = 7.5 (from Table 2.2-1)
Per this Tech. Spec., the Power Range NIS is recalibrates whenever its indication is in error > 2%
from indicated Reactor Thermal Power.
During the j
subject incident an error in the calculation of Reactor Thermal power on the Plant Operator Aid Computer created indications of thermal power y 3% lower than actual power level.
Since this error was not realized
{
at the time, Operations personnel directed I and E 1
personnel to recalibrates the Power Range NIS channels
'to match the erroneous thermal power level.
This 1
resulted in the Power Range NIS being 23%
nonconservative with respect to the High Flux Reactor Trip Setpoint, (the worst channel was 3.1%
nonconservative).
The error in the Reactor Thermal Power Heat Balance was discovered and corrected within two hours of the erroneous NIS recalibration and the NIS was promptly recalibrates to restore the required conservatism.
An invalid evaluation of Equation 2.2-1 was performed within the specified 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> as follows:
i The value of "R" was assumed to be 0.5 (per station I and E personnel contacted) and the value of "S" used was zero as indicated on Table 2.2-1.
The value of "Z"
used was 5.96, which was derived by the Nuclear Safety Group in Design Engineering and assumes an inherent NIS/ Thermal Power mismatch of 5%.
The "Z" value of 4.56 provided by Table 2.2-1 assumes a mismatch of 2%.
The new value of Z had been derived due to considerable interest in the past in adopting a looser interpretation of the Tech. Spec. requiring recalibration of the Power Range NIS whenever mismatchess in excess of 2% with indicated reactor thermal power exist, (the intent being to eliminate multiple recalibrations during power ascension following shutdowns or load decreases).
This erroneous Equation 2.2-1 analysis showed no violation of safety limits (i.e. the Trip Setpoints' Allowable Value on Table 2.2-1 was not exceeded).
However, since unapproved (from a Tech Spec standpoint) values were used in this analysis it was not, in effect, performed to the satisfaction of the Tech. Spec's 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Action Statement and hence the violation was incurred.
3.
Corrective Actions Taken and Results Achieved An exhaustive evaluation of the intended application of Equation 2.2-1 with respect to the Power Range NIS by Performance, Station I and E, Westinghouse, and Design Engineering's Nuclear Safety personnel has resulted in the following interpretation:
Equation 2.2-1:
Z + R + S < TA Z=
4.56 (from Table 2.2-1, which allows for a 2%
mismatch between NIS and Thermal Power l
indications)
R=
(X - 2) + 0.1 1.2 l
where : X= the mismatch between NIS and Thermal Power indications
!C_
7.-
L m.
l
~
o
'(X-2):
deducts the allowed 2% mismatch'which is already accounted for in the "Z"
term (X-2):
adjusts this difference for the 1.2 proper percent of enan (120%)
0.1.= the worst expected NIS channel rack drift between calibrations (per I and E personnel as substantiated by review of Monthly Channel Calibration Procedures)
S=
0.0 (from Table 2.2-1, an assumed value of zero for an Ion Chamber field device)
TA = 7.5 (As assigned by Table 2.2-1)
Adopting this interpretation of Equation 2.2-1, the evaluation of this avent yields the following result:
Z
+
R
+
S
- TA 4.56 +
(3.1-2) + 0.1
+ 0.0 1 7.5 1.2 5.577 1 7.5
.Which verifies that no safety Limits were violated during the subject event.
4.
Corrective Actions to be Taken to avoid further violations A Tech. Spec. Interpretation shall be issued to clarify the application of Equation 2.2-1 to ensure that it is properly applied to perform required evaluations within the specified 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
5.
Date of Full Compliance January 1, 1988
_________d
DUKE POWER COMPANY RESPONSE TO VIOLATION 50-413/87-30-02 50-414/87-30-02 10 CFR 50, Appencix D, Criterion XII as implemented by Quality Assurance Program (Duke 1-A, Amendment 10) Section 17.2.12 requires in part that measures be established to assure that instruments and measuring devices used in activities affecting quality are properly calibrated and adjusted at specified periods to maintain accuracy within necessary limits. Standing Work Request 006091 SWR specified a calibration period of 18 months (with a 25 percent grace period) for pressure switch ICAPS 5131.
Contrary to the above, the licensee failed to established adequate measures to assure that all instruments and measuring devices used in activities affecting quality were calibrated and adjusted at specified periods to maintain accuracy within necessary limits, in that pressure switch 1 CAPS 5131 was not calibrated from installation in April, 1984 until July 7, 1987, exceeding the specified calibration and grace period.
Twenty other safety-related instruments were also identified as having exceeded their specified calibration and grace periods.
RESPONSE
(1) Admission or Denial of Violation I
Duke Power Company admits the violation.
(2) Response for Violation if Admitted l
No evidencs can be found to account for this condition.
Construction records indicate ICAPS 5131 was installed in April, 1984 under F-13A#6724.
No completad work request or calibration information could be located to support tb Anitial calibration. However, the licensee has reason to believe thi; calibration did occur because the circuit performed its function on July 17, 1986. The licensee did identify and indicate an SWR for this safety related instrument.
Instruments identified in this report were not calibrated by the initial SWR, but were being phased into the work schedule by Integrated Scheduling, Planning and the Instrument and Electrical sections as manpower and plant conditions permitted.
(3) Corrective Actions Taken and Results Achieved Instrument ICAPS 5131 was checked and valved back in service under work request 5749PRF on July 7, 1987.
Instrument Details were reviewed to verify if additional instruments should be added to the Instrument Startup Checklist. The Instrument Valve Checklist was issued on (CA) (NS) systems to ensure all identified instruments were in service.
Integrated Scheduling phased the 20 Standing Work Roquests into the Weekly Operating Schedules and work as completed December 7, 198.
Factors to consider were plant conditions, equipment availability, manpower and priority activities. Of the 20 SWR's, eleven were in tolerance or in a conservative direction. The other results are tabulated as follows:
(Note: OOT = Out Of Tolerance)
.a
.e RESPONSE TO' VIOLATION PAGE 2 SWR SYSTEM FUNCTION RESULTS 4102 (WL - Liquid ND & NS Rooms Sump Level,
-OOT Waste Recycle Pump IB.
Setpoints were
-Recalibrates System) slightly out of tolerance
-Returned to Service (non-conservative) but still well below sump overflow.
4103 (WL - Liquid ND & NS Rooms Sump Level,
-OOT Waste Recycle Pump 2B.
Setpoints were
-Recalibrates System) slightly out of tolerance
-Returned to Service (non-conservative) but still well below sump overflow.
4378 (YC - Control Train B YC Chiller Condenser -Repaired Area Chill Water pressure control loop was
-Recalibrates System) out of service due to
-Returned to Service i
several maintenance and installation problems.
Although closer operator attention was required, Condenser pressure could still be maintained and the Control Room Ventilation remained operable.
5966 (VZ - Nuclear RN Pumphouse Temperature
-Repaired Service H20 Control Damper 1B not
-Recalibrates Pump Ventilation controlling, however,
-Returned to Service System) damper 2B was operational and could control temperature. No excessive temperature swings were reported.
6070 (VF - Fuel Pool Temperature Switch IVFTS5950 -Recalibrates Ventilation High Temperature Heater
-Returned to Service System)
Cutoff with manual reset was not functional.
It was replaced. Temperature Switch IVFTS5940 High Temperature Heater Cutoff with automatic reset was functional with the correct setpoint. Therefore, heater protection for Fan Unit lA2 was available. Other instruments were in tolerance or conservative.
s 0
RESPONSE TO VIOLATION-PAGE 3 SWR SYSTEM FUNCTION RESULTS 6071 (VF.- Fuel Pool IVFT1001A Time Delay was
-Recalibrates Ventilation inoperable. The Time Delay
-Returned to Service System)
Relay was replaced. The purpose of the time delay is to allow override of the smoke detection actuation circuit.
Both override and actuation functions were operable.
6174 (VG - Diesel
- 1) 1VGPSS270 D/G Engine "E"
-OOT Generator air supply was OOT.
-Recalibrates l
Engine Start IVGPS5250 monitors
-Returned to Service I
Air System) pressure for the front air supply header.
It was found in tolerance under the same SWR.
These two switches provide interlocks to redundant D/G engine start circuits to prevent the engine from starting on low starting air pressure. Since IVGPS5250 l
was found in calibration i
the D/G would have started, as required.
- 2) 1VGPS5230 which starts D/G starting air compressor 1B1 on a low pressure in starting I
air tank 1B1 was found with its setpoint 5 psi higher than required. This would have ensured the compressor to start earlier than actually needed, which is jn the conservative direction.
Therefore, no problem would have resulted.
6183 (VF - fuel Pool 2VFTS5920 High Temperature
-Recalibrates Ventilation Heater Cutoff with
-Returned to Service System) automatic reset was out of service.
It was replaced, j
2VFTS5930 High Temperature Heater Cutoff with Manual Reset was functional but out of tolerance - high.
Even though it was set high, i
an engineering judgement is that no Fan Unit 2A1 heater damage would have occurred in that temperature range.
l
RESPONSE TO VIOLATION PAGE 4 SWR SYSTEM FUNCTION RESULTS i
7017 (VF - Fuel Pool IVFTS5960 High Temperature
-Recalibrates j
Ventilation Heater Cutoff with
-Returned to Service System) automatic reset was out of service.
It was replaced.
l IVFTS5970 High Temperature l.
Heater Cutoff with Manual Reset was functional with correct setpoint. Therefore, I
Fan Unit 1B1 heater i
l protection was available.
I l
(4) Cggrective Actions to be Taken to Avoid Further Violations i
Added the following pressure switches to IP/1(2)/A/3820/17A Instrument j
Status Checklist: 1(2) CAPS 5131, 1(2) CAPS 5141, 1(2) CAPS 5151.
IAE is developing administrative controls to ensure that all additions and changes to instrumentation will be added to the surveillance program as appropriate (i.e., Safety-Related and Technical Specification instrumentation will be j
added to the program). A Maintenance Procedure will be written to define adequate calibration measures for new instrumentation added per NSM's (procedure to be completed by April 1, 1988.
j (5) Date of Full compliance Full Compliance to be accomplished by April 1, 1988.
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