ML20011D941
| ML20011D941 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 12/27/1989 |
| From: | Walt T PORTLAND GENERAL ELECTRIC CO. |
| To: | |
| Shared Package | |
| ML20011D937 | List: |
| References | |
| NUDOCS 9001030099 | |
| Download: ML20011D941 (6) | |
Text
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I PORTLAND GENERAL ELECTRIC COMPANY EUGENE WATER & ELECTRIC BOARC AND PACIFIC POWER &' LIGHT COMPANY Operating License NPF-1 Docket 50-344 License Change Application 189 r
f This License Change Application requests an emergency change to the Technical Specifications for the chlorine monitors.
PORTLAND GENERAL ELECTRIC COMPANY
- t By
'T. D. Walt '
General Manager i
Technical Functions Subscribed and sworn to before me this 27th day of december, 1989.
Ikk A. JQ AlY Mf N
f Notary Putll6 of Oregon U
My Commission Expires:
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'N LCA 189 Attachment A Page 1 of 6 r
Description of Emergency Conditions On December 12, 1989, it was discovered that the chlorine detector response time could be longer than am smed in the toxic gas analysis. As a result,-both trains of chlorine detsctors were declared inoperable per Trojan Technical Specification (TTS) 3.3.3.6, " Chlorine Detection Systems", and the Control Room Emergency Ventilation System (CB-1B) was pieced in the recirculation mode of. operation as required by the appropriate action statement.
This caused a conflict with TTS 3.7.6.1,
" Control Room Emergency Ventilation System" Which requires the Control Room Emergency Ventilation System (CB-1) to be.available for automatic initiation upon receipt of a safety injection (SI) signal. With one train of CB-1 in recirculation, it was no longer in the automatic initiation lineup and the ACTION statement of TTS 3.7.6.1 applies (i.e.,
the train of CB-1 in recirculation must be restored to operable status within seven days). This seven day period began on December 12, 1989.
To allow compliance with TTS 3.7.6.1, PGE revised the Technical Specification Bases to redefine the term " recirculation mode of operation" to allow both trains of CB-1 to remain in " AUTO" with CB-1 and CB-2 outside air makeup dampers closed.
The details of the Bases change are described in Attachment C.
In addition, with the Control Room isolated, carbon dioxide (CO ) tends-2 to build to unhealthy levels for habitation. 'In discussions with the NRC on December 15, 1989, the NRC acknowledged PGE's need to enter into TTS 3.0.3 in order to ventilate the control room to maintain habitability per Occupational Health and Safety Administration (OSHA)-requirements.
Before entry into TTS 3.0.3 is made, PGE takes appropriate compensatory measures to protect the control room operators in the event a toxic gas accident occurs during the ventilation process.
The specific compensatory measures that were discussed with the NRC are providcd in Attachment B.
Based on current data it appears.that such'ventilations need to be performed approximately every 24 to-48 hours, i
Additionally, the CB-1B pressurization Surveillance required by TTS 4.7.6.1.b is scheduled for December 30, 1989.
f.pplying the extension allowed by TTS 4.0.2.a defers the surveillance until January 6,'1990.
(This date is within the 3.25 interval required by TTS 4.0.2.b.).This i
l-test cannot be performed while the Control Room oetaide makeup air j
dampers are. closed.
The problem with the potentially excessive response time of the chlorine detectors was only recently discovered (December 12,.1989).
All available resources have been applied to correct this problem:
test equipment was obtained to determine the actual detector response times; a reanalysis of toxic gas effects on Control Room personnel has been performed to determine the actual response time necessary; and efforts were made to locate replacement detectors (see Attachment D).
The need for this emergency change could not be foreseen or avoided.
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'I LCA 189 Attachment A Page 2 of 6 Response time testing of the detectors has shown that the detectors are' unreliable and cannot meet the design criteria.
The reanalysis of toxic gas effects indicates that a response time of 19 seconds is acceptable.
Replacement detectors have been ordered and will be installed as soon as possible after. qualification testing.
The schedule for installing the new detectors is provided in Attachment D.
Purpose of Change The purpose of this change is to:
1.
Allow performance of Trojan Technical Specification Surveillance Requirement 4.7.6.1.b, " Control. Room Rmergency Ventilation System" while both chlorine detectors are inoperable.
2.
Allow for ventilation of the Control Room atmosphere with both chlorine detectors inoperable.
Description of Change i
Add an asterisk (*) at the end of Technical Specification 3.3.3.6 Action b. 'On TTS page 3/4 3-47, add the following footnote:
l j-For the purpose of meeting Specification 4.7.6-1.b or for providing periodic air exchanges to maintain air quality in the control room, the outside air makeup dampers for the normal and/or emergency control room ventilation systems may be opened for up to one hour provided that appropriate compensatory measures are taken to isolate the-control room if a woxic gas accident should occur. This-process it permitted until new chlorine detectors are made OPERABLE, on approximately March 15, 1990."
The proposed page is shown on Page 6 of this attachment.
Determination of Significant Hazards Consideration In accordance with Requirements of Title 10, Code of Federal Regulations (CFR), Part 92, this LCA is' judged to involve no significant hazards i
based upon the following information:
1.
Does the proposed license change involve a significant increase in.
the probability or consequences of an accident previously evaluated?
t This change does not involve a significant increase in the probability or consequences of an accident.
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LCA 189 l
Attachment A page 3 of 6 e
The probability of a chlorine release which could affect Trojan is l
unaffected by this change as the proposed change concerns mitigation of a chlorine accident.
Chlorine release detection and subsequent mitigation of the consequences of a chlorine accident would normally be provided by the chlorine detectors. Compensatory measures were i
then designed to detect and protect from chlorine releases earlier than would normally be provided by the chlorine detectors.
The Trojan Final Safety Analysis Report (FSAR) indicates that the r
chlorine onsite is stored in the Chlorine Building.
To minimize the I
probability of a release from this source, the following compensatory measures are taken when both chlorine detectors are inoperable and outside makeup air is being brought into the control Room 1.
No chlorine shipments may be received, 2.
No evolutions / activity involving the use of chlorine in the Chlorine Building are permitted, and i
3.
Chlorine levels will be monitored in the chlorine Building.
These measures will ensure that the probability of a chlorine release from the Chlorine Building will be no greater than that previously analyzed in the FSAR and that any chlorine release from the Chlorine Building will be promptly detected and reported to the Control Room.
The Trojan FSAR indicates that offsite transportation of chlorine occurs on the Burlington Northern railroad tracks which are 150 meters west of the Plant, and on the railroad tracks 1800 meters east of the Plant on the Washington side of the Columbia River. To guard against possible chlorine accidents from the railroad tracks west of the Plant, the following compensatory measures are taken when both chlorine detectors are inoperable and outside makeup air is being l
brought into the Control Room:
1.
Communications are established between the Control Room and a guard in observation of the railroad tracks west of Trojan to alert the Control Room of passing trains, and 2.
Outside air makeup dampers (CB-1 and/or CB-2) will be closed and the associated ventilation system stopped whenever a train approaches and passes Trojan on' the railroad tracks west of the Plant.
To detect possible chlorine accidents on the railroad tracks east of the Plant when both chlorine detectors are inoperable and outside.
i makeup air is being brought into the Control Room either:
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LCA 189 Attachment A Page 4 of 6 l
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1.
An observer will be posted who can observe the railroad tracks east of Trojan on the Washington side of the Columbia River and report any train derailment, and f
2.
Outside air makeup dampers (CB-1 and/or CB-2) will be closed and the associated ventilation system stopped whenever a l
train derails on the railroad tracks east of Trojan on the r
Washington side of the Columbia River, t
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t 1.
Communications will be established between the Control Room i
and an observer posted at the Intake Structure who can alert l
the Control Room when the odor of chlorine is detected, and 2.
Outside air makeup dampers (CB-1 and/or CB-2) will be closed and the associated ventilation system stopped whenever the observer at the intake Structure detects the odor of chlorine.
The FSAR lists two locations where chlorine is stored in the vicinity of Trojan. Both of these chlorine storage locations are in Cowlitz County, Washington.
In the event of a chlorine release from either of these locations, the Control Room would be notified of the release by the Cowlitz County Emergency Services and Disaster Agency which has notification procedures in place.
If both chlorine detectors are inoperable, and if outside makeup air is being brought into the 1
Control Room, and if notification of an offsite chlorine accident is received, then outside air makeup dampers (CB-1 and/or CB-2) will be closed and the arsociated ventilation system stopped until it is confirmed that the release is terminated and poses no hazard to 1
Troj an.
These measures will ensure that the consequences of any chlorine release from offsite transportation or storage of chlorine will be no 1
greater than that previously analyzed in the FSAR and that any chlorine release will be promptly detected and reported to the 1
Control Room.
l 2.
Does the proposed license change create the possibility of a new or different kind of accident from any previously evaluated?
a This change does not create the possibility of a new or different kind of accident as the TTS 4.7.6.1.b surveillance is not changed
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(CB-1 makeup dampers for outside air opened). Allowing for the surveillance to be performed with inoperable chlorine detectors is of concern only for a toxic gas release. Because of compensatory measures (Attachment B) the Control Room can still be operated within the assumptions of the toxic gas analysis and thus does not create a I
new or different accident.
l LCA 189 Attachment A page 5 of 6
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Does the proposed license change involve a significant reduction in a margin of safetyt i
This change does not involve a significant reduction in a nortin of l
safety as compensatory measures provide for detection and j
I notification of the control Room in the event of a chlorine gas accident.
I Safety / Environmental Evaluation j
Safety and environmental evaluations were performed as required by l
10 CFR 50 and the TTS. The review determined that the proposed change as
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discussed above does not create an unreviewed safety question, nor does it have an effect upon the environment and thus does not create an unreviewed environmental question. As such an environmental assessment t
in accordance with 10 CFR 51 is not necessary.
t Schedule Consideration A stated earlier, this change is being submitted as an emergency change request.
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JSW/bsh 4117W.1289
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