ML20137C148

195-96 Annual Progress Rept, Replacing Pages IV-6,IV-11 & IV-12

ML20137C148
Person / Time
Site:	05000083
Issue date:	12/31/1996
From:	FLORIDA, UNIV. OF, GAINESVILLE, FL
To:
Shared Package
ML20137C117	List: ML20137C115 ML20137C134 ML20137C148
References
NUDOCS 9703240164
Download: ML20137C148 (4)

Text

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- ATTACIIMENT II 1995-96 Annual Progress Report Replacement Pages IV-6, IV-11 and IV-12 ,

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4. biocraiv Zone 2 and 3 Bvoass on Fire Alarm System for Pipinn Reolacement (Temporary -

ClosedItem)

(Modification 95-07: Determination Completed 09 October 1995)

.i This 10 CFR 50.59 Determination was generated to address the temporary bypass of the Smoke Detectors in Zones 2 and 3 for piping ranhemmant which required welding. The zones were continuously occupied during working hours and reconnected during non-working hours. This change was evaluated and determined not to involve any unreviewed safety

. questions. No further problems were noted.

Controlling Document: 10 CFR 50.59 Determination #95-07

5. . Elimination of Ouarterly Check of Air Handler Condeneate for Contamination (0-10 SurvaHinnce) (Permanent - Closed Item)

(Modification 95-08: Evaluation Completed 26 October 1995)

This 10 CFR 50.59 Evaluation was generated to address the discontinuation of the Q-10 surveillance which required sampling and analysis of the air handler condensate for contamination.

In a memorandum dated September 13,1995 from the Radiation Control Officer to the Facility Director, the RCO recommended that sampling and analysis of the air handler condensate (Q-10 Surveillance) be discontinued. This recommendation was based on the rerouting of the air handler condensate discharge pipe to the sink in the cell which eliminated a potential unmonitored release point in January,1993 and is controlled as 10 CFR 50.59 Evaluation Number 95-08. Other data was supplied as well showirig essentially negative determinations in the sample analysis performed from August,1991 through August,1995.

The RSRS approved this change at its meeting on October 26,1995.

Controlling Document: 10 CFR 50.59 Evaluation #95-08

6. ' Stack Monitor Rustrak Recorder Meter Movement Reolaced and Meter Soan Calibration Circuit Installation (Permanent - Closed Item) ,

(Modification 96-01: Evaluation Completed 14 March 1996)

- This 10 CFR 50.59 Evaluation was generated to address the replacement of the failed 100 pA l meter movement with a 50 pA meter movement along with a modification in the form of a 1 linear calibration circuit to allow adjustment / calibration of the recorder meter span to keep  :

the recorded values within the range of the recorder.

IV-6

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9 Temocrary Replacement ofFire Alarm System Batteries (Temporary - Closed Item)

(Modification 96-04: Evaluation Completed 25 April 1996)

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. This 10 CFR 50.59 Evaluation was generated to address the temporary replacement of the four zone fire alarm system monitoring panel batteries with a used set of higher rated batteries, until new superior rated batteries which had been ordered could arrive and be

, installed, to eliminate battery trouble indications. Under MLP #96-14 and 10 CFR 50.59 l Evaluation Number 96-04, the work was completed and the system tested, with no further

problems noted. .-

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Controlling Documents

Maintenance Log Page #96-14 (Closed 18 April 1996) 10 CFR 50.59 Evaluation #96-04 i

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10. Enoxy Bonding ofMechanical Tachometer Manter (Permanent - Closed Item) i j (Modification 96-05

Evaluation Completed 06 June 1996)

This 10 CFR 50.59 Evaluation was generated to address the epoxy bonding of the mechanical tachometer adapter to the stack dilute fan pulley to ehminate slipping which resulted in an

] unreliable and decreased rpm indication in the control room.

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) Under 10 CFR 50.59 Evaluation Number 96-05 and MLP #96-11, a modification was approved to affix the shaft coupling using JB Weld epoxy which was completed on 3 May 1996. Subsequently, on' 7 May 1996, the lead wires were reattached to the mechanical I tachometer which was reinstalled in its bracket whereupon tubing was attached. The diluting j fan was then started with no problems. The mechanical tachometer,was reading 530 rpm

while the optical tach digital readout read 534 rpm which was evaluated as good. The l tachometer was evaluated throughout the remainder of 7 May until late afterr.oon on 8 May

with no problems. At this point with the mechanical tach reading 535 rpm on the control room indicator, the strobe tach was used to verify the value at 535 rpm also. MLP# 96-11 I

was closed with no further problems noted.

. Controlling Documents: Maintenance Log Page #96-11 (Closed 08 May 1996) I 10 CFR 50.59 Evaluation #96-05 4

11. Replacement of Fire Alarm System Batteries with Higher Rated Batteries (Permanent -

i Closed item)

(Modification 96-06: Evaluation Completed 08 May 1996)

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i This 10 CFR 50.59 Evaluation was generated to address the replacement of the fire alarm i system monitoring station batteries with improved model batteries.

IV-11

i Previously under MLP #96-14 and 10 CFR 50.59 Evaluation Number 96-04, higher grade j used batteries were placed in the fire alarm monitoring station for backup power when the regular batteries began to fail on 18 April 1996, with new batteries placed on order. The new I

battries arrived on 8 May 1996. Under reopened MLP #96-14 and the new 10 CFR 50.59

Evaluation Number 96-06, the used batteries were replaced with new higher grade 7.0

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ampere-hour batteries with no further problems noted.

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j Controlling Documents: Maintenance Log Page #96-14 (Closed 08 May 1996) l 10 CFR 50.59 Evaluation #96-06 i .

12. Temoorary Replacement of Safety Channel 2 HVPS for Troubleshooting (Temporary -

Closed Item)

(Modi 6 cation 96-07: Evaluation Completed 12 July 1996)

This 10 CFR 50.59 Evaluation was generated to address the temporary repla::ement of the Safety Channel 2 high voltage power supply (HVPS) with an identical supply, to be used as a variable voltage power source to allow testing of the Safety Channel 210% loss of high voltage trip circuit.

On 10 July 1996, the Quarterly Scram Checks (Q-1 Surveillance) were being performed as scheduled after last having been successfully performed on 27 March 1996. Upon performance of step 6b (Neutron Chamber High Voltage Reduction for Safety Channel 2),

Safety Channel 2 failed to effect a water drop and blade drop full trip as required when a test

. pushbutton was depressed simtdating a 10% loss of high voltage. Because of earlier problems, this test had last been checked cperable on 15 April 1996 following a series of spurious trips as discussed in an 25 April report to the NRC. Under Maintenance Log Page (MLP) #96-23, the high voltage to the detector was verified to be normal at 841.6.VDC; however, upon inspection of the resistor string which reduced the high voltage to a 4 VDC sensing circuit, a resistor was found to be intermittent. Subsequently, on 11 July 1996, the resistor was removed from the string and verified to be functional. The solderjoint to the mounting post was a cold solderjoint, limiting the contact of the resistor. However, when the resistor was correctly reinstalled, the trip circuit was still inoperative in that pushing the test pushbutton did not effect a loss-of-high-voltage trip on Safety Channel 2. Under 10 CFR 50.59 Evaluation #96-07, the Safety Channel 2 high voltage power supply (HVPS) was temporarily replaced with an identical supply, to be used as a variable voltage power source.

The voltsge was then reduced until the trip occurred at 727 VDC (a 13.6% voltage drop); this

, value was noted to be outside the Tech Spec limit of 10% loss of high voltage to yield a trip per UFTR Technical Specifications Section 2.2(5) and Table 3.1 on Limiting Safety System Settings. At this point the sensing circuit system was adjusted to trip at 8.6% and tested satisfactorily three times. On 12 Juiy 1996, the circuit was again tested, but would not effect a trip unless the sensitivity of the comparator circuit was raised to 789 VDC (~6.3% voltage drop, a more conservative setting). The circuit was left at that setpoint and again tested satisfactorily three times.

IV-12