ML19323A056
| ML19323A056 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 03/31/1980 |
| From: | Trimble D ARKANSAS POWER & LIGHT CO. |
| To: | Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| NUDOCS 8004170086 | |
| Download: ML19323A056 (6) | |
Text
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t ARKANSAS POWER & LIGHT COMPANY POST OFFICE BOX 551 UTTLE ROCK. ARKANSAS 72203 (501) 371-4000 r
March 31, 1980, 1-030-14 2-030-11 Mr. K. V. Seyfrit, Director Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission i
Region IV 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76011
Subject:
Arkansas Nuclear One-Units 1 and 2 Docket Nos. 50-313 and 50-368 License Nos. DPR-51 and NPF-6 10 CFR 50.59 Design Changes (File:
0520.2, 2-0520.2)
Gentlemen:
In accordance with 10 CFR 50.59, attached is a report containing a brief description of our safety evaluation for design changes made to Arkansas Nuclear One - Units 1 and 2 (ANO-1 and 2).
This report contains only those design changes which required a safety evaluation and were com-pleted in 1979.
Very truly yours, f
[ David C. Trim le i
Manager, Licensing DCT:.%S:nak cc:
Mr. Victor Stello, Jr., Director
$0/9 Office of Inspection and Enforcement O
U. S. Nuclear Regulatory Commission Washington, D. C.
20555 MEM9EA MCCLa SCW UTiuTIES SYSTEM 8 0 04170 0 8 r.
ANO-1&2 DCR's DCR 644 - Emergency Cooling Pond Modification Completion Date: August 27, 1979 The downstream sections of the spillway crest, areas which appeared to bare voids, and the adjacent embankment were pumped with an elastic type of grout. To protect the pond side slopes against wave action, rip rap was placed 18" deep all around the pond. A compatible clay was placed on the north side of the pond to eliminate leakage through the existing filter material to the underdrain. A series of weirs was constructed to eliminate part of the silt problem from the drainage pattern.
The spillway grout addition assures that the spillway will perform as assumed with minimal maintenance. Addition of the rip rap will prevent future erosion of the pond banks. The addition of weirs will help eliminate the silting problem and will not prevent the pond from per-forming as assumed in the safety analyses.
ANO-1 DCR'.s l
DCP 661 - Firehose Station Addition f
Completion Date: September 19, 1979 A firehose station with 100' of 1.5" CRL firehose and an adjustable nozzle was provided at EL 317'-0" in the reactor auxiliary building.
This addition creates no new accident possibilities, nor increases the probability of any accidents previously analyzed in the safety analysis.
DCR 79-1013 - Increase of Sprinkler Coverage Completion Date:
September 19, 1979 As a result of NRC fire protection review for ANO-1, wet pipe sprinkler coverage was provided for the Condensate Demineralizer Area to protect safety related cables.
The sprinkler coverage does not cover the entire demineralizer area but only the area where safety related cables are rcuted.
This modification does not create any situation not previously analyzed in the safety analysis, nor does it increase the probability of any previously analyzed event. A tech. spec. change which was
- required for this DCR is administrative in nature.
I ANO-2 DCR's DCR 33-Drain Lines Completion Date: January 8,1979 A number of drain lines for the Wet Pipe Sprinkler Systems in the Aux-i iliary Building Extension were combined to reduce the number of drain lines required. The deleted system connections were capped off. Jul -
nunciation windows were also combined.
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Since the drains do not perform a safety function and are not required to mitigate the consequences of an accident, the changes do not reduce the margin of safety.
DCR 2 Revise Sensing Contacts from Hand Switch to Starter Breaker Contracts Completion Date: April 2, 1979 To correct computer indication, the sensing contacts from some hand-switches to the starter bre;ker contacts were changed. These changes were made in the Boric Acid / Waste Condensate System.
This modification provides for transmittal to the computer of the cor-rect equipment condition. Neither the computer nor the modifications made are necessary to mitigate the consequences of an accident.
DCP 2 Fire Main Relocation Completion Date: April 9, 1979 In order to allow for construction of the maintenance facility, the fire l
main north of the plant road was relocated.
Since the fire protection system is not a safety system and is not required to mitigate the consequences of an accident, relocation of this fire main will not decrease the margin of safety to the public.
DCR 2 Piping Revision Completion Date: April 2, 1979 I
T This modification adds piping to a process radiation monitor to allow for an acceptable method of calibration of the monitor. As this change does not affect monitor operation, no situation is created which has not been previously analyzed in the safety analysis, nor is the probability of occurrence increased for any situation previously' analyzed in the safety analysis.
t DCR 2 Revised Piping for Calibration of Monitors Completion Date: April 2, 1979 The piping to several monitors was changed to allow for an acceptable method of calibration of the monitors. These changes included the addition of vents, drains, and in-line isolation valves.
This change does not affect monitor operation and, therefore, does not create a situation which has not been previously analyzed in the safety analysis, nor is the probability of occurrence increased for any event previously analyzed in the safety analysis.
The margin of safety to the public is not decreased.
DCR 2 Revised Piping to Allow for Monitor Calibration Completion Date: April 2, 1979 The piping to a process acnitor was changed to allow for an acceptable i
method of calibration of the monitor. Vents, drains, and in-line iso-i lation valves were added.
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This change does not affect monitor operation and, therefore, does not create a situation which has not been previously analyzed in the safety analysis, nor is the probability of occurrence increased for any event previously analyzed in the safety analysis.
The margin of safety to the public is not decreased.
DCR 2 Addition of Sight Glasses and Pressure Indicator in the Demineralizer Room Completion Date: March 29, 1979 Three in-line sight glasses and one differential pressure indicator were installed in the demineralizer room to improve observation of resin t
transfer operations.
These additions will supply the operator with additional information to ensure that the resin transfer operation is going as desired. No sit-untion is created which has not been previously analyzed in the safety analvsis. The margin of safety to the public health and safety is not l
decreased.
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DCR 79-2016 - Provide Cooling to Area Above Control Room Completion Date: April 10, 1979 i
The ventilation system to the area above the false ceiling in the Con-l trol Room was re-routed to provide for cooling the annunciator panels.
Approximately 4% of the total Control Room air flow was re-routed.
i Habitability of the Control Room was not affected since the system will still r.emove heat. The probability or consequences of previously ana-lyzed accidents will not be increased, nor will the possibility of any new accidents be increased. The margin of safety based on the tech.
specs.will not be decreased.
DCR 79-2017 - Relief Valve Added in Cross-Tie Between Seal Supp1v Lines Completion Date: December 14, 1979 l
A relief valve was added in the cross-tie between the seal supply lines downstream of the pressure control valves in the heater drain pump seal l
system.
This system does not perform a safety function and is not required to mitigate the consequences of an accident. Therefore, the change will neither increase the probability or consequences of a previously ana-lyzed accident nor will it create the possibility of any new accident.
DCR 79-2018 - Changes to the Condenser Hotwells I
Completion Date: December 15, 1979 A high differential water level existed between the high and low pres-I sure condenser hotwells. To correct this, an existing pressure equal-i izing line was replaced with a larger duct.
Tubing was also re-routed to eliminate interference with the duct. Also, internal condenser pipe j
inodifications were made to re-route the drains from two nozzles.
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4 These modifications were made to improve condenser service, nd will not increase the probability or consequences of a previously analyzed ac-cident. The possibility of a new accident will not be created nor will the margin of safety as related to the health and safety of the public be reduced.
DCR 79-2019 - Changes to the Main Feedwater Pump Seal Injection Completien Date: December 13, 1979 To avoid the potential contamination of main feedwater pump and turbine bearing lube sil with seal water via the adjacent seal cavity, several changes were maie: Seal injection leak-off valves were locked open; four valves were removed; and the intertie between the leak-off heads and the seal cavits drip drain was eliminated by re-routing the cavity drip lines to floor drains.
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This change was made to improve system reliability and will not create the possibility of any new accident nor will it increase the probability or conseqc:::.-s of a previously analyzed accident. The margin of safety as related to the health and safety of the public is not decreased.
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