Event Notification Report for March 18, 2007
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
03/17/2007 - 03/18/2007
EVENT NUMBERS
43247
Power Reactor
Event Number: 43247
Facility: DUANE ARNOLD
Region: 3 State: IA
Unit: [1] [] []
RX Type: [1] GE-4
NRC Notified By: HANS OLSON
HQ OPS Officer: BILL HUFFMAN
Region: 3 State: IA
Unit: [1] [] []
RX Type: [1] GE-4
NRC Notified By: HANS OLSON
HQ OPS Officer: BILL HUFFMAN
Notification Date: 03/18/2007
Notification Time: 22:07 [ET]
Event Date: 03/18/2007
Event Time: 19:40 [CDT]
Last Update Date: 03/18/2007
Notification Time: 22:07 [ET]
Event Date: 03/18/2007
Event Time: 19:40 [CDT]
Last Update Date: 03/18/2007
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
RICHARD SKOKOWSKI (R3)
RICHARD SKOKOWSKI (R3)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | M/R | Y | 28 | Power Operation | 0 | Hot Shutdown |
MANUAL REACTOR SCRAM DUE TO COOLANT CHEMISTRY CONCERNS
"This report Is being made under 50.72(b)(2)(iv)(B) for inserting a manual reactor scram due to high levels of reactor coolant chlorides, sulfates, and conductivity. These elevated chemistry parameters may be due to a possible resin intrusion following the placement of a Condensate Demineralizer in service.
"In addition, this report is being made under 50.72(b)(3)(iv)(A), 'Any event or condition that results in valid actuation of any systems listed in paragraph (b)(3)(iv)(B) of this section' due to PCIS groups 2, 3, and 4 being received when reactor water level dropped below 170 inches. All isolations went to completion. The reactor water level drop is normal following a scram from 28% power due to void collapse in the reactor vessel. Reactor water level was restored to normal and the PCIS group isolations were reset.
"The current plan is to cooldown the plant and enter Mode 4."
The scram was characterized as uncomplicated. All rods fully inserted. No safety relief valves lifted. Reactor water low level was approximately 165 inches and was restored with normal reactor feedwater. Decay heat is currently being removed via steam line drains. There were no electrical alignment or grid issues as a result of the transient. No significant Technical Specification LCOs were in effect at the time of the scram.
The licensee notified the NRC Resident Inspector.
"This report Is being made under 50.72(b)(2)(iv)(B) for inserting a manual reactor scram due to high levels of reactor coolant chlorides, sulfates, and conductivity. These elevated chemistry parameters may be due to a possible resin intrusion following the placement of a Condensate Demineralizer in service.
"In addition, this report is being made under 50.72(b)(3)(iv)(A), 'Any event or condition that results in valid actuation of any systems listed in paragraph (b)(3)(iv)(B) of this section' due to PCIS groups 2, 3, and 4 being received when reactor water level dropped below 170 inches. All isolations went to completion. The reactor water level drop is normal following a scram from 28% power due to void collapse in the reactor vessel. Reactor water level was restored to normal and the PCIS group isolations were reset.
"The current plan is to cooldown the plant and enter Mode 4."
The scram was characterized as uncomplicated. All rods fully inserted. No safety relief valves lifted. Reactor water low level was approximately 165 inches and was restored with normal reactor feedwater. Decay heat is currently being removed via steam line drains. There were no electrical alignment or grid issues as a result of the transient. No significant Technical Specification LCOs were in effect at the time of the scram.
The licensee notified the NRC Resident Inspector.