ML18051A779
| ML18051A779 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 01/30/1984 |
| From: | Johnson B CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| GL-82-28, NUDOCS 8402030259 | |
| Download: ML18051A779 (11) | |
Text
.. ~
consumers Power company General Offices: 1945 West Parnall Raad, Jackson, Ml 49201 * {517) 7f;l$.-0550 January 30, 1984 Dennis M Crutchfield, Chief Operating Reactor Branch No 5 Nuclear Reactor Regulation US Nuclear Regulatory Commission Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT - RESPONSE TO GENERIC LETTER 82 ADDITIONAL INFORMATION NRC letter dated December 14, 1983 documented the review of Consumers Power Company's earlier submittals in response to NRC Generic Letter 82-28 entitled Inadequate Core Cooling Instrumentation System, and requested further informa-tion to clarify the proposed system and implementation schedule.
The intent of this submittal is to give the status of our plans for Inadequate Core Cooling Instrumentation (ICCI) implementation at Palisades and provide as much of the requested information as is available.
Consumers Power Company has continued to pursue a plant-specific ICCI design based on the generic Westinghouse approach.
We expect results from this initial design study to be available from Westinghouse within one month.
However, we recently became aware of an alternate type of reactor vessel level system which appears to have several advantages the Palisades Plant.
This approach utilizes a new type of Heated Junction Thermal Couple (HJTC) probe from Technology for Energy Corporation and is similar to the system proposed for the Combustion Engineering Unit at Arkansas Power and Light.
Telephone conferences with the NRC Staff have indicated that concurrence with this approach would be subject to the qualification tests at ORNL and that further discussion of the Palisades application should probably be delayed until the ORNL tests results are available.
Our plans are to pursue this alternate approach with Technology for Energy corporation (TEC) in parallel with finalizing the plant-specific Westinghouse RVLS design.
We will provide a final s.ubmittal in April 1984, based on the best system for application at Palisades.
The original installation schedule, which was question~d in NRC letter dated December 10, 1982 has been changed due to the extension of the present refuel-ing outage.
This extension appears to provide the opportunity for installa-tion of either ICCI system under consideration during the next refueling OC0184-0006AA-NL02 r--s4020302s9 040130 PDR ADOCK 05000255 I
p PDR
J DMCrutchfield, Chief Palisades Plant RESPONSE TO GENERIC LETTER 82-28 January 30, 1984 outage which is now expected in late 1985.
final proposal will support this schedule.
Enclosure A.
2 Your concurrence in May of our A proposed schedule is included in The additional information requested in the NRC letter dated December 14, 1983 and available at this time are provided in Enclosure A.
Final responses on the reactor vessel level portion of the ICCI, questions 7 and 8, will depend on the type of system chosen and will be supplied in April 1984.
However, the upgraded core exit thermocouple (CETC) system is essentially on independent system, except for readout methods.
Therefore, we are providing responses to CETC review questions at this time to support timely resolution of this portion of the ICCI system.
Please note that in our earlier submittal we misunderstood the definition of primary and backup display system and are now responding accordingly.
Please advise us if there are further questions or if an information meeting should be arranged.
If not, we will plan to contact the NRC Palisades Project Manager in March regarding a final submittal in April 1984.
Brian D Johnson Staff Licensing Engineer CC Administrator, Region III, USNRC NRC Resident Inspector - Palisades Enclosure OC0184-0006AA-NL02
I' *.
- I I
I OC0184-0006B-NL02 ENCLOSURE A Consumers Power Company Palisades Plant - Docket 50-255 RESPONSE TO GENERIC LETTER 82-28 January 30, 1984 8 Pages
- l.
In the April 14 submittal, the RVLIS display was erroneously designated as the primary CET display.
The intended primary CET display will be from the Critical Function Monitoring System (CFMS), which was recently installed at Palisades to provide the SPDS function.
The CFMS is a computer based system with human factored color graphic CRT displays.
Although the CET display software has not been designed yet, the capabilities of the CFMS will allow for displays consistent with NUREG~0737, Part II.F.2, Attachment 1, item (2) which includes.
- a.
A spatially orie?ted core map indicating temperature at each thermocouple location.
- b.
Selective reading of highest thermocouple or average temperature.
- c.
Direct readout with hard copy for all 16 thermocouples.
- d.
Trend capability showing temperature time history.
The CFMS is non-IE and powered from a non-IE bus, but it is provided with a battery back-up.
The CETs will be routed from the containment to a qualified signal processing unit.
The CET temperature signals will then be fed to the CFMS, through a qualified isolation device, and to the qualified backup display units.
The CFMS display CRT will be located between the operators desks in the main control room (Fig l). Additional display units are located in the TSC, the EOF and at the General Office in Jackson.
Alarm contacts in this unit will be used to activate an alarm in the existing qontrol room annunciator system.
The range capability of the readouts is limited only by the thermocouples themselves.
The proposed range will be 0-2300°F.
The desi~ concept for the CETs is shown in Fig 2, block diagram of system.
- 2.
As stated above the range of the CET readouts will be 0-2300°F and a control room alarm will be provided from alarm contacts in the signal processing unit.
The primary CET readout will be the CFMS display located between the control room operators desks*.
The backup display, is located on panel Cll-A in the right rear of the control room.
The SMM display is located on the front control board.
All of these locations are shown in Fig l.
3 Emergency operating procedures (EOPs) will be revised to inc'lude guidelines for when to use the primary core exit thermocouple display.
Guidelines for actions based on the core exit thermocouple readings will be developed from the recommendations of the CE owners group.
The operators will be trained on these procedures, which will describe when to use or not use the core exit thermocouples and what actions to take based on information from the CETs.
Doc ID 5968A
1..
i *.**
i* ':..,
- 4.
As stated above, our original submittal erroneously referred to existing CFMS as "backup".
The new RVLIS display units will be used as the CET backup displays.
These displays will be qualified to IEEE-323 (1974) with seismic qualification to IEEE-344 (1975).
These displays will be powered from a vital instrument bus which is electrically independent from 480 volt bus Bl4 which powers the CFMS through MCC No
- 4.
- 5.
Qualification of the Core Exit Thermocouples will be discussed as follows on a component basis (Ref: Fig 2):
- a.
Thermocouples - The thermocouples are an integral part of the standard incore instrument probe used in Combustion Engineering reactors.
The probes are manufactured by Reuter Stokes for CE, and are not currently qualified in accordance with NUREG-0588,however CE is considering entering into a qualification program for the probes.
At Palisades the incore probes are replaced each refueling due to difficulties encountered with re-insertion of incore probes which have been in the core for a fuel cycle.
- b.
Thermocouple cable - The thermocouple cable can be broken into three distinct groupings: 1) cable from the thermocouple/probe to the disconnect panel near the reactor, 2) cable from the disconnect panel to the containment penetration, 3) cable from the containment penetration to the control room.
Group 1 cable - This cable is a multiconductor cable containing both incore instrumentation and chrome-alumel thermocouple wires.
Although this cable was originally not required to be qualified, the jacket material of this cable was originally specified to be of a material which has previously been qualified.
If cable insulation can not be qualified under the CPCo EEQ program, this cable will be replaced.
The cables in this group are routed from the 8 instrument nozzles up to a disconnect panel on the refueling deck.
Group 2 cable - This cable is of a type identical to the Group 1 cable.
Again, if the cable cannot be qualified under the CPCo EEQ program, it will be replaced.
The cables in this group currently all run together in a single cable tray system from the disconnect panel to the containment penetrations.
At the containment wall, the cables are divided equally between two adjacent penetration cannisters.
This arrangement of the cables does not meet the separation criteria of
.IEEE-384 (1977), however we have analyzed the tray for potential failures per Section 6 of IEEE-379 (1977), and have concluded that major modificaions to the system are not justified.
Failure modes which have been considered include seismic, high energy line break (both missile and jet impingement), fire and environmental.
Separation for fire protection is not considered applicable since CETs are not required for plant shutdown following a fire.
Flooding and environmental considerations will be dispositioned by the Consumers Power Company EEQ program as previously mentioned.
In areas where HELE missiles or jet impingement are a concern, the trays will either be protected or re-routed.
2
Group 3 cable -
As is the case with Group 2 cables, these cables are routed together in a single cable tray system from the penetrations to the control room.
These trays will be analyzed for single failure similar to the group 2 cable.
In the control room, the cables are routed to a reference junction within an existing data logger used for incore readouts, rod position indications and some rod control functions.
From the reference junction, 16 thermocouple signals will be routed to a qualified signal processing unit.
- c.
Disconnect panel connectors - The existing connectors are ITT Cannon type CVGE-24-75 plugging into receptacles of type ITT cannon CVOE-24-7P.
This connection is not LOCA qualified.
CPCo plans to replace this connection with a Celmark connector which is qualified.
Thermocouple connectors -
The thermocouple connectors which are currently in use at Palisades are Physical Sciences model Tl06-12-105-Fl, and are not qualified to NUREG-0588.
These connectors will be replaced with qualified connectors if such connectors are commercially available. If qualified connectors are not commercially available, Raychem heat shrink tubing will be used to sleeve the existing connectors to-provide an improved moisture barrier.
Penetration connectors - Existing connectors are not qualified.
They will be replaced with Celmark connectors which have been previously qualified for use at Palisades.
- d.
Signal Processing/Readout - The qualification of these components is described in answers 1 & 4.
- 6.
The Reactor Core Plan submitted on April 14 is in error.
Attached to this letter is a revised Reactor Core Plan (Fig 3) showing the location of the selected 16 upgraded core exit thermoc?uples, four per quadrant.
- 7.
(The answer to this question is contained in the Westinghouse licensing report).
- 8.
(The answer to this question is contained in the Westinghouse licensing report)'.
- 9.
A description of the proposed RVLIS display is not available at this time.
The arrangement of reactor vessel internals at Palisades differs from the current generation of CE plants in the respect that there is no barrier between the upper head region and the core region which would inhibit the movement of water or voids between them.
At Palisades the upper guide structure (UGS) is open and hence we do not feel that it is possible to-have the upper head remain full of water with voiding in the core region. Additionally, the RVLIS adaption for Palisades will only indicate level above the core, i.e., there is no indication of level in the core region.
3
- 10.
Due to unexpected extension of the present refueling outage at Palisades, the next refueling has moved from early 1985 to about November 1985.
We now expect to be able to complete installation of all three portions of ICCI during the 1985 refuleing outage, rather than the October 1986 schedule previously submitted.
The attached schedule outlines major milestones and target dates based on the now expected 1985 refueling outage period.
In response to, item 10 of your letter, upgrading of SMM and CET systems will be completed along with core level in the 1985 refueling outage.
In response to the request in the main body of your letter, following are specific schedule points for the items listed in your Enclosure 3:
- l.
Submit final design description - April 15, 1984 - This submittal will provide final plant-specific description for the complete system, based on the reactor vessel level approach to be chosen in March.
- 2.
Approval of EOP technical guidelines - May 15, 1984.
- 3.
Inventory Tracking System Installation Complete - 1985 refueling outage, now expected to start in November 1985.
- 4.
ITS function testing and calibration - Three (3) months following the 1985 refueling outage.
- 5.
Prepare revisions to plant operating procedures and emergency procedures based on approved EOF guidelines - By the end of the 1985 refueling outage.
- 6.
Implementation letter report to NRC ~ Four (4) months following the 1985 refueling outage.
- 7.
Perform procedure walkthrough*to complete task analysis portion of ICC system design - Three (3) months following the end of the 1985 refueling outage.
- 8.
Turn on system for operator training and familiarization - Two (2) weeks prior to the end of the 1985 refueling outage.
- 9.
Approval of plant-specific installation by NRC - Five (5) months following th~ 1985 refueling outage (Assumes one month final review after implementation letter).
- 10.
Implement modified operating procedures and emergency procedures
- Six (6) months following the 1985 refueling outage.
4
L __
PALISADES ICCI IMPLEMENTATION SCHEDULE 1/1/85 1/1/86 11111111111111111111111 111111 2/1/84 I
PR~ECTED OPERATING CYCLE~~~~*~~~~~~~~~~~~~~~efuel~~~~
FINAL DESIGN SUBMITTAL-NRC
/). 4 /15 /84 NRC REVIEW & APPROVAL f-t. 5/15/84 CETC DESIGN/PROCUREMENT CETC INSTALLATION SMM DESIGN/PROCUREMENT SMM UPGRADE INSTALLATION RVLS FINAL DESIGN/PROCURMT RVLS INSTALLATION SYSTEM TESTING/CALIBRATION DEVELOP OP PROCEDURES OPERATOR TRAINING FUNCTIONAL TESTING PERIOD IMPLEMENTATION LTR TO NRC NRC FINAL APPROVAL OPERATIONAL I
I I
k I
I
- I r
A A
A A 6/1/86 fj7/l/86
/j 8/1/86
Technical Support Center with CFM/SPDS Display Figure 1 SS/Shift Eng Office MAIN CONTROL PANELS (SMM Display)
CONTROL CONSOLE
!Op Desk I I Op Des~
"--..___/ ' ~
<:_ CFMS/SPDS Display CRT
. (Primary ICCI Readout) z 0
H E-i u i:il E-i 0
~
p..
~
0 E-i u <
i:il
~
[Future Qualified Backup ICCI Displays]2 TMI Modifications Panel PALISADES CONTROL ROOM - ICCI LOCATION
~
i:il
~
p..
z 0
H E-i <
E-i Cl)
Disconnect Panel
.Connector
- Group 2 Cable Disconnect Panel I Reference 1 I Junction. ;
I I
I IE ----.
Non-IE Signal Process-Isolati
._ __...,. ing lhit Device CFMS 1--- TSC 1--* EDF Group 1 Cable 1hermocouple Connector I
Group 3 Cable Back-up Display
.*Primary Display In Control Room
~-----------------------J Core Exit 1hermocouple In Cbnta'irunent
<<----l1---11--- Penetration Connector
,V
~
Outside Containment IE --
~Non-IE PALISADES CET MONITORING SYSTEM (Typical for 16 'ihermocouples)
\\
~
I
- N A
\\
B C 0 E F G
2 4
- Upgraded CET e
Appendix E
- e
- Palisadas Plant*- Reactor* C'°re. Pfon 142 11 PRlt.11\\RY OUTLET]
H I" J
K L. -M N P Q
R *s T
V \\V X
. Z
. Figure 3 0 = Fu.JI ~cr.gth \\'~nc.::;;m
@ = Fu.l I Le;1gth Cobo It
@.=Leng bcckgTound
© :. shot+ bacJ<i9~td 2
3 4
5