ML042040249
| ML042040249 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 06/03/2004 |
| From: | NRC/OE |
| To: | |
| References | |
| FOIA/PA-2004-0243 | |
| Download: ML042040249 (2) | |
Text
Page 1 of 2 Follow-Up Assignment Sheet (Detail)
Assigned To: TELSON, ROSS D Facility: NINE MILE POINT Vendor Name:
pReported By:----
50.72 No: 40684 Event Dt: a MR No:
HQ MR No:
TAC No:
Part 21 No:
IN No:
BL No:
PN No:
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Assignment Dt: 06/03/2004 Unit 2 050-00410 Region No. 1 GL No:
I Insp. Rpt. No:
I IRS No:
RIS No:
)4/18/2004 Event Type:
HQ MR Dt:
Briefing No:
LER No:
Inspection Type:
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Submitted by:
Closeout Reviewed by:
I Approved by:
Submitted Dt:
Closeout Dt:
Approved Dt:
Event
Description:
RETRACTION RESIDUAL HEAT REMOVAL SYSTEM ISOLATION DUE TO A RISE IN REACTOR PRESSURE "At 1830 hours0.0212 days <br />0.508 hours <br />0.00303 weeks <br />6.96315e-4 months <br /> on 18 April 2004, Nine Mile Point Unit 2 was restoring from reactor pressure vessel leakage test.
"Reactor pressure was -82 psi, temperature -178 degrees, reactor level was solid with both reactor recirculation pumps running in slow speed per the leak test procedure.
" 'B' residual heat removal system was being warmed up in preparation for going in to service.
Reactor water cleanup reject from the vessel was secured to maintain RPV [Reactor Pressure Vessel] pressure stable in order to provide driving head for flow through the residual heat removal discharge line to radwaste.
The line is warmed up from the reactor, back through the Shutdown cooling isolation valve, to radwaste prior to placing shutdown cooling in service.
When warm-up criteria are met, the operating procedure directs securing flow.
When flow was secured, this effectively isolated the solid reactor vessel, resulting in a rise in reactor pressure.
Pressure peaked at -146 psi before operators established reactor water cleanup reject flow.
"When RPV pressure reached 128 psi, the residual heat removal system isolation was automatically initiated as designed. The shutdown cooling injection valve, which was open to support piping warm-up, closed as designed. All other shutdown cooling valves were closed prior to the event per the warm-up lineup."
RPV is currently depressurized with shutdown cooling in service. All systems are functioning as expected.
The licensee notified the NRC Resident Inspector.
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Page 2 of 2 Follow-Up Assignment Sheet (Detail) w w w xir^tu-riuN on Ub/Ul/U4 at ibli Mar rrom unris uinner co jonn macsinnon w.
"The following is a retraction of ENS Notification #40684: On April 18, 2004, Nine Mile Point Unit 2 reported Residual Heat Removal Shutdown Cooling System isolated due to a pressure spike while warming up the piping. The shutdown cooling injection valve, which was open to support piping warm-up, closed as designed.
All other shutdown cooling valves were closed prior to the event per the warm-up lineup.
Accordingly, Control Room personnel conservatively initiated ENS reporting under 10CFR50.72(b)(3)(iv)(A) in response to the valid containment isolation signal.
"Subsequent analysis has concluded that, although the isolation signal was valid, it was not a general containment isolation signal (i.e., the isolation signal only involved the shutdown cooling system) and the shutdown cooling function of the Residual Heat Removal System is not listed under 10CFR50.72(b)(3)(iv)(B) as a system that is required to be reportable.
This system isolation does not meet the reporting requirements of 10CFR50.72(b)(3)(iv)(A).
"Therefore, this notification made on April 18, 2004, is being retracted.
The NRC Resident Inspector was notified."
NRC RlDO (Ron Bellamy) notified.
Assignment:
Review of retraction.
6/16/04:
Reassigned from Foster to Telson.