Event Notification Report for July 25, 2001
U.S. Nuclear Regulatory Commission
Operations Center
Event Reports For
07/24/2001 - 07/25/2001
** EVENT NUMBERS **
38164 38165 38167 38168
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|Power Reactor |Event Number: 38164 |
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| FACILITY: CLINTON REGION: 3 |NOTIFICATION DATE: 07/24/2001|
| UNIT: [1] [] [] STATE: IL |NOTIFICATION TIME: 05:59[EDT]|
| RXTYPE: [1] GE-6 |EVENT DATE: 07/24/2001|
+------------------------------------------------+EVENT TIME: 02:51[CDT]|
| NRC NOTIFIED BY: LARRY WESTEROOK |LAST UPDATE DATE: 07/24/2001|
| HQ OPS OFFICER: FANGIE JONES +-----------------------------+
+------------------------------------------------+PERSON ORGANIZATION |
|EMERGENCY CLASS: NON EMERGENCY |MONTE PHILLIPS R3 |
|10 CFR SECTION: | |
|ARPS 50.72(b)(2)(iv)(B) RPS ACTUATION - CRITICA| |
| | |
| | |
| | |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1 A/R Y 100 Power Operation |0 Hot Shutdown |
| | |
| | |
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EVENT TEXT
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| AUTOMATIC REACTOR SCRAM ON HIGH REACTOR VESSEL LEVEL |
| |
| The reactor scrammed at 0251 CDT on 7/24/20001 on a level 8 signal, a high |
| reactor vessel level. All rods fully inserted and all systems functioned |
| properly. At the time of the scram there was a surveillance being performed |
| on a level transmitter that feeds the feedwater level control system. |
| Exactly what happened is not known at this time, but an investigation is |
| ongoing. |
| |
| The plant is stable using the bypass valves to the condenser and level is |
| being maintained with motor driven feedwater pump. |
| |
| The licensee notified the NRC Resident Inspector. |
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|Power Reactor |Event Number: 38165 |
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| FACILITY: ARKANSAS NUCLEAR REGION: 4 |NOTIFICATION DATE: 07/24/2001|
| UNIT: [1] [] [] STATE: AR |NOTIFICATION TIME: 10:00[EDT]|
| RXTYPE: [1] B&W-L-LP,[2] CE |EVENT DATE: 07/24/2001|
+------------------------------------------------+EVENT TIME: 06:39[CDT]|
| NRC NOTIFIED BY: PATRICK WILLIAMS |LAST UPDATE DATE: 07/24/2001|
| HQ OPS OFFICER: FANGIE JONES +-----------------------------+
+------------------------------------------------+PERSON ORGANIZATION |
|EMERGENCY CLASS: NON EMERGENCY |GARY SANBORN R4 |
|10 CFR SECTION: | |
|ARPS 50.72(b)(2)(iv)(B) RPS ACTUATION - CRITICA| |
| | |
| | |
| | |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1 N Y 100 Power Operation |0 Hot Standby |
| | |
| | |
+------------------------------------------------------------------------------+
EVENT TEXT
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| AUTOMATIC REACTOR TRIP ON HIGH REACTOR COOLANT SYSTEM PRESSURE |
| |
| The unit received an automatic reactor trip on high reactor coolant system |
| pressure due to a problem with the main turbine control valves. There were |
| no ESF actuations and all rods fully inserted. Steam generator safeties |
| opened for a short period as expected. The plant is stable in hot shutdown |
| with excess heat being controlled by condenser bypass valves with main |
| feedwater system controlling steam generator level. |
| |
| The problem is being investigated and the cause is unknown at this time. |
| |
| The licensee notified the NRC Resident Inspector and state agencies. |
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|Power Reactor |Event Number: 38167 |
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| FACILITY: SEABROOK REGION: 1 |NOTIFICATION DATE: 07/24/2001|
| UNIT: [1] [] [] STATE: NH |NOTIFICATION TIME: 17:35[EDT]|
| RXTYPE: [1] W-4-LP |EVENT DATE: 07/24/2001|
+------------------------------------------------+EVENT TIME: 15:50[EDT]|
| NRC NOTIFIED BY: HUGH HAWKINS |LAST UPDATE DATE: 07/24/2001|
| HQ OPS OFFICER: BOB STRANSKY +-----------------------------+
+------------------------------------------------+PERSON ORGANIZATION |
|EMERGENCY CLASS: NON EMERGENCY |JOHN WHITE R1 |
|10 CFR SECTION: | |
|APRE 50.72(b)(2)(xi) OFFSITE NOTIFICATION | |
| | |
| | |
| | |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR| INIT RX MODE |CURR PWR| CURR RX MODE |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1 N Y 100 Power Operation |100 Power Operation |
| | |
| | |
+------------------------------------------------------------------------------+
EVENT TEXT
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| OFFSITE NOTIFICATION DUE TO EXCEEDING NPDES PERMIT LIMITS |
| |
| "The EPA and NH Department of Environmental Services (NHDES) were notified |
| this afternoon of a daily maximum exceedence of the NPDES Permit limit for |
| oil and grease at Outfall 025 (Waste Test Tank). The discharge occurred on |
| July 3, 2001. The amount of the exceedence is minor but the significance is |
| still being evaluated so this report is being made as a conservative |
| decision." |
| |
| The NRC resident inspector has been informed of this notification by the |
| licensee. |
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|Fuel Cycle Facility |Event Number: 38168 |
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| FACILITY: PORTSMOUTH GASEOUS DIFFUSION PLANT |NOTIFICATION DATE: 07/25/2001|
| RXTYPE: URANIUM ENRICHMENT FACILITY |NOTIFICATION TIME: 05:28[EDT]|
| COMMENTS: 2 DEMOCRACY CENTER |EVENT DATE: 07/24/2001|
| 6903 ROCKLEDGE DRIVE |EVENT TIME: 12:30[EDT]|
| BETHESDA, MD 20817 (301)564-3200 |LAST UPDATE DATE: 07/25/2001|
| CITY: PIKETON REGION: 3 +-----------------------------+
| COUNTY: PIKE STATE: OH |PERSON ORGANIZATION |
|LICENSE#: GDP-2 AGREEMENT: N |PATRICK HILAND R3 |
| DOCKET: 0707002 |C.W. (BILL) REAMER NMSS |
+------------------------------------------------+ |
| NRC NOTIFIED BY: SISLER | |
| HQ OPS OFFICER: CHAUNCEY GOULD | |
+------------------------------------------------+ |
|EMERGENCY CLASS: NON EMERGENCY | |
|10 CFR SECTION: | |
|NBNL RESPONSE-BULLETIN | |
| | |
| | |
| | |
| | |
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EVENT TEXT
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| 24 - HOUR 91-01 BULLETIN - LOSS OF ONE CONTROL OF THE DOUBLE CONTINGENCY |
| PRINCIPLE |
| |
| On 7-24-01 at 1230 hours, a process operator in the X-330 Building |
| discovered a NCSA-0330_004.A05 noncompliance with cell 29-4-6. Cell 29-4-6 |
| is a shutdown cell at a UF6 negative and was buffered above 14 psia. Over |
| time the pressure decrease to 13.96 psia. This violated NCSA-0330_004.A05 |
| requirement #8 resulting in a loss of one control (moderation) of the double |
| contingency principle. Mass (second control) was maintained throughout the |
| event. |
| |
| NCSA-0330_004.A05 requirement #8 states in part, "Within 8 hours after |
| cascade equipment shutdown (motor turned off) and with the system at a UF6 |
| negative, the system shall be pressurized with plant air or N2 buffer at > |
| 14 psia, unless the equipment is undergoing maintenance, pre and post |
| maintenance troubleshooting, being evacuated or treated." |
| |
| Buffer pressure was increased to greater than 14 psia at 1300 hours. |
| Moderation control was re-established for cell 29-4-6. |
| |
| The safety significance of this event is low. There is no deposit in this |
| cell. The worst case would be contamination on process surfaces exposed to |
| process gas prior to shutdown and buffering. |
| |
| This event is reportable per NRC BL 91-01 as a loss of one control of the |
| double contingency principle. |
| |
| SAFETY SIGNIFICANCE OF EVENTS: |
| |
| The safety significance of this event is low. There is no deposit in the |
| cell (thus is less than a safe mass for an H/U=4 and the cell is isolated |
| from the cascade. The mass in the cell is controlled by virtue of the fact |
| that the shutdown cell is isolated from the cascade which is also shutdown. |
| If the unbuffered condition were permitted to continue for a long period of |
| time, the H/U could eventually reach a maximum of 4. However, since any |
| material in the cell is less than the safe mass H/U ratio, a criticality |
| would not occur even if the H/U reached the maximum through the loss of a |
| buffer. |
| |
| POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO(S) OF HOW |
| CRITICALITY COULD OCCUR): |
| |
| The cell would need to be unisolated and UF6 introduced to create a deposit. |
| That deposit would then have to become sufficiently moderated in order for a |
| criticality to occur. |
| |
| CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.): |
| |
| The parameters controlled are mass and moderation. |
| |
| ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDE PROCESS |
| LIMIT AND % WORST CASE OF CRITICAL MASS): |
| |
| There is no deposit in this cell. Worst case would be contamination on |
| process surfaces exposed to process gas prior to shutdown and buffering. |
| |
| NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION |
| OF THE FAILURES OR DEFICIENCIES |
| |
| The NCS control is a dry air buffer >14 psia. Over time the pressure |
| decreased to 13.96 psia. |
| |
| CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEM AND WHEN EACH WAS IMPLEMENTED: |
| |
| Buffer pressure was increased to greater than 14 psia at 1300 hours. |
| Control was re-established. |
| |
| The NRC Resident Inspector was notified along with the DOE Representative. |
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Page Last Reviewed/Updated Thursday, March 25, 2021
Page Last Reviewed/Updated Thursday, March 25, 2021