ML18051A545
| ML18051A545 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 08/15/1983 |
| From: | CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | |
| Shared Package | |
| ML18051A543 | List: |
| References | |
| TASK-15-02, TASK-15-2, TASK-RR NUDOCS 8308230382 | |
| Download: ML18051A545 (3) | |
Text
NU080983-NL01 ENCLOSURE 2 CONSUMERS POWER COMPANY PALISADES PLANT DOCKET 50-255 Palisades Plant Operating Procedure Review August 15, 1983 53 Pages
ENCLOSURE 2 PALISADES PLANT OPERATING PROCEDURE REVIEW Palisades Emergency Operating Procedures (EOPs) were reviewed to determine their adequacy with regard to a postulated main steam line break (MSLB) concurrent with a main steam isolation valve (MSIV) failure, followed by a blowdown of both steam generators (SGs) and possibly an auxiliary f eedwater (AFW) induced SG tube failure.
There is no EOP for the postulated sequence of events.
The EOPs address only single events; not sequences of failures.
The following EOPs were reviewed with regard to their use during the proposed event.
Copies of these procedures and a copy of Off Normal Procedure ONP-21, which is referenced in EOP 1, are attached with this review.
These procedures have been abridged by removal of cover sheets and some attachments.
EOP 1 EOP 6 EOP 7 EOP 8.1 EOP 8.2 ONP 21 "Reactor Trip" (Attachment 1)
"Main Steam Line Break/Main Feedwater Line Break Inside Containment" (Attachment 2)
"Main Steam Line Break/Main Feedwater Line Break Outside Containment (Attachment 3)
"Loss of Coolant Accident" (Attachment 4)
"Steam Generator Tube Rupture" (Attachment 5)
"Natural Circulation" (Attachment 6)
The NRC expressed concern that the Palisades EOPs were inadequate for the proposed sequence of events.
The NRC expressed the specific concern that the SG tube failure procedure would direct the operator to secure the high pressure safety injection (HPSI) pumps thereby losing the ability to remove decay heat.
The symptoms presented to the operator during the blowdown of both SGs would initially be similar to those for a MSLB without a MSIV failure and to those for a loss of coolant accident (LOCA).
An attachment to procedures EOP 6, 7 and 8.1 entitled "ACCIDENT IDENTIFICATION LARGE BREAKS" would guide the operators to EOP 6 or EOP 7.
The immediate actions prescribed by either of these procedures, including references to EOP 1 and to ONP 21 are proper for the two SG blowdown case as well as the intended event.
The subsequent actions of EOP 6 or EOP 7 (MSLB Inside or Outside Containment) are proper except for the statements requiring identification and isolation of the faulted SG.
The new AFW system will include motor operated valves which automatically isolate the faulted SG.
The operator, however, will have the ability to re-open these isolation valves if necessary.
The procedures have not yet been revised to include that change.
NU080983-NL01
If a SG tube failure should occur following the two SG blowdown, the symptoms available to the operator would most likely be the failure of pressurizer level and pressure to stabilize and/or recover rather than those symptoms listed in EOP 8.1 (LOCA) or EOP 8.2 (SG Tube Rupture); where the incident is assumed to initiate from normal operating conditions.
Most all of the immediate actions required by EOP 8.1 are covered by both EOP 6 and EOP 7.
At this point, either procedure EOP 1 (Reactor Trip), EOP 6 (MSLB Inside Containment), EOP 7 (MSLB Outside Containment) or EOP 8.1 (LOCA) have directed the operator to ensure that containment isolation has initiated and to verify operation of all ECCS equipment.
The procedures then discuss balance of plant actions and recovery.
Conditions required prior to reset of SIS are listed in EOP 1 Step 4.10 as follows:
4.10 If safety injection has actuated, reset only after all of the following conditions are met, insuring that hot and cold leg temperatures are at least 50°F subcooled per Attachment #2 (also posted in the Control Room) using all available instrumentation including all hot and cold leg temperatures, several incore thermocouples, PCS Pressure.
(a)
The cause of the low-pressure condition is known and corrected.
(b)
The reactor is shutdown and will remain shutdown.
(c)
Pressurizer level is greater than 20% and is returning to normal.
(d)
Tave is stable or increasing and is less than 545°F.
(e)
Pressurizer pressure is greater than 1700 psia and is returning to normal.
If after a reset of the Safety Injection System 50°F subcooling cannot be maintained, restart the High Pressure Safety Injection System.
Other steps which require stopping HPSI pumps are EOP 8.1 Step 4.12.b.l (which requires one HPSI pump left running), and EOP 8.1 Step 4.14.b.2(a) (which secures HPSI only after initiating shutdown cooling)
- NU080983-NL01