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Event Notification Report for April 21, 2000

                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           04/20/2000 - 04/21/2000

                              ** EVENT NUMBERS **

36908  36909  36910  36911  

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|Power Reactor                                    |Event Number:   36908       |
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| FACILITY: SAN ONOFRE               REGION:  4  |NOTIFICATION DATE: 04/20/2000|
|    UNIT:  [] [2] [3]                STATE:  CA |NOTIFICATION TIME: 11:43[EDT]|
|   RXTYPE: [1] W-3-LP,[2] CE,[3] CE             |EVENT DATE:        04/20/2000|
+------------------------------------------------+EVENT TIME:        07:45[PDT]|
| NRC NOTIFIED BY:  CLAY WILLIAMS                |LAST UPDATE DATE:  04/20/2000|
|  HQ OPS OFFICER:  DICK JOLLIFFE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |DALE POWERS          R4      |
|10 CFR SECTION:                                 |                             |
|AOUT 50.72(b)(1)(ii)(B)  OUTSIDE DESIGN BASIS   |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     N          Y       100      Power Operation  |100      Power Operation  |
|3     N          Y       100      Power Operation  |100      Power Operation  |
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                                   EVENT TEXT                                   
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| - HPSI, LPSI & CS SYSTEMS OUTSIDE THEIR DESIGN BASIS DUE TO LACK OF          |
| INSTALLED INSULATION -                                                       |
|                                                                              |
| The following is the text of a fax received from San Onofre:                 |
|                                                                              |
| This notification from San Onofre Units 2 and 3 is being made in accordance  |
| with 10CFR50.72(b)(1)(ii)(B) for the condition of the High Pressure Safety   |
| Injection (HPSI), Low Pressure Safety Injection (LPSI) and Containment Spray |
| (CS) Systems being outside their design basis.  This condition exists for    |
| both Units 2 and 3.                                                          |
|                                                                              |
| On 04/19/00, during an NRC inspection, it was discovered that portions of    |
| the ECCS piping were not insulated as assumed in design calculations.        |
| Affected lines are the suction and discharge piping for the HPSI Pumps       |
| #P017, P018 & P019, LPSI Pumps #P015 & P016, and CS Pumps #P013 & P014. The  |
| consequence of the missing insulation is that the heat loads in the ECCS     |
| pump rooms will be higher than assumed in the plant accident analyses.       |
|                                                                              |
| At 0745 PDT on 04/20/00, SCE concluded that ECCS pump room temperatures      |
| during certain accident scenarios may not remain below their design basis    |
| room temperatures of 104F.  However, the equipment in the pump rooms        |
| continues to be operable at the calculated higher post-accident              |
| temperatures.  That is, even with the higher than expected ECCS pump room    |
| temperatures, the affected equipment would continue to be able to perform    |
| its intended safety function.                                                |
|                                                                              |
| SCE has installed some temporary insulation and will take actions to install |
| permanent insulation on the affected piping.  SCE's investigation of this    |
| occurrence is ongoing; the cause of this condition will be reported in the   |
| followup 30 day licensee event report.                                       |
|                                                                              |
| At the time of this discovery, both Units 2 and 3 were operating at about    |
| 100% power: Unit 1 remains permanently defueled.  SCE plans to notify the    |
| NRC Resident Inspectors about this issue and will provide them with a copy   |
| of this event report.                                                        |
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|Power Reactor                                    |Event Number:   36909       |
+------------------------------------------------------------------------------+
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| FACILITY: INDIAN POINT             REGION:  1  |NOTIFICATION DATE: 04/20/2000|
|    UNIT:  [2] [] []                 STATE:  NY |NOTIFICATION TIME: 14:02[EDT]|
|   RXTYPE: [2] W-4-LP,[3] W-4-LP                |EVENT DATE:        04/20/2000|
+------------------------------------------------+EVENT TIME:        09:30[EDT]|
| NRC NOTIFIED BY:  KEVIN DONNELLY               |LAST UPDATE DATE:  04/20/2000|
|  HQ OPS OFFICER:  DICK JOLLIFFE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |JOHN WHITE           R1      |
|10 CFR SECTION:                                 |ED GOODWIN           NRR     |
|AOUT 50.72(b)(1)(ii)(B)  OUTSIDE DESIGN BASIS   |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|2     N          N       0        Cold Shutdown    |0        Cold Shutdown    |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| - UNIT 2 S/Gs PRIMARY-TO-SECONDARY DESIGN DIFFERENTIAL PRESSURE OUTSIDE      |
| DESIGN BASIS -                                                               |
|                                                                              |
| Indian Point Unit 2 received a letter from Westinghouse (the NSSS Supplier)  |
| which stated that Westinghouse is in the process of completing a Nuclear     |
| Safety Advisory Letter regarding the primary-to-secondary design pressure    |
| differential in the steam generators. The current design pressure listed in  |
| the equipment Specification is 1550 psid.  With an anticipated steam         |
| generator outlet pressure in the 650 to 660 psia range, this design pressure |
| will be exceeded.  However, Indian Point Unit 2 has an analysis that         |
| determined that the limiting structure within the steam generator, the tube  |
| sheet, can withstand a pressure differential of 1750 psid. This issue may be |
| addressed by updating the design pressure and stress reports demonstrating   |
| compliance with the ASME Code as governed by Section IWA-4312, Re-rating, of |
| Section Xl of the ASME Code.                                                 |
|                                                                              |
| The licensee plans to notify the NRC Resident Inspector.                     |
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+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   36910       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: SAINT LUCIE              REGION:  2  |NOTIFICATION DATE: 04/20/2000|
|    UNIT:  [] [2] []                 STATE:  FL |NOTIFICATION TIME: 17:38[EDT]|
|   RXTYPE: [1] CE,[2] CE                        |EVENT DATE:        04/17/2000|
+------------------------------------------------+EVENT TIME:        10:20[EDT]|
| NRC NOTIFIED BY:  STEVE MERRILL                |LAST UPDATE DATE:  04/20/2000|
|  HQ OPS OFFICER:  DICK JOLLIFFE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |ANN BOLAND           R2      |
|10 CFR SECTION:                                 |DAVID MATTHEWS       NRR     |
|NINF                     INFORMATION ONLY       |CHUCK DePUY          FEMA    |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     N          N       0        Hot Shutdown     |0        Hot Shutdown     |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| - RCS LEAKAGE CRITERIA FOR DECLARING AN UNUSUAL EVENT EXISTED ON 04/17/00 -  |
|                                                                              |
| At 1020 on 04/17/00, St. Lucie Unit 2 was in Mode 4 in a refueling outage    |
| preparing to go on shutdown cooling.                                         |
| A pre-job brief was conducted and included a discussion of the potential for |
| pressurizer level change, relief valve lifting and the need to monitor the   |
| telltale on containment spray isolation valve #MV-07-3 to determine valve    |
| leakage. The expectation was established that the operating crew would       |
| terminate the evolution if unexpected leakage was observed with the primary  |
| focus on the telltale tubing monitoring containment spray isolation valve    |
| #MV-07-3.                                                                    |
|                                                                              |
| The control room operator observed a sudden drop in pressurizer level once   |
| the last shutdown cooling isolation valve was opened (6% drop on the hot     |
| calibration indication).  The valve was immediately closed and pressurizer   |
| level stabilized; the evolution duration was approximately 3 minutes.  As    |
| the valve was closing, the field operator stated he was seeing leakage       |
| through the tygon tubing, which he estimated to be about 1 to 2 gpm.  There  |
| was no increase in sump level and no abnormal interfacing system behavior.   |
| Operations department personnel believed the behavior observed was           |
| consistent with filling shutdown cooling lines.                              |
|                                                                              |
| Subsequently, the on-shift engineer performed an inventory balance and,      |
| without adjusting for changing temperatures and pressures, estimated a 100   |
| gpm leak had occurred.  The Nuclear Plant Supervisor (NPS) did not feel the  |
| inventory balance was valid in that he knew the accuracy of the calculation  |
| was biased because of the effect of temperature and pressure and the short   |
| duration of the event.  Based on the discrepancy between the calculation and |
| field observation, the NPS had a condition report issued to determine the    |
| RCS leak rate.                                                               |
|                                                                              |
| The NPS rationale for not entering the Emergency Plan and that RCS leakage   |
| was not greater than 10 gpm was based on the following:                      |
|                                                                              |
| - his field operator's observations showed a 1-2 gpm leak,                   |
| - a lack of any increase in sump level,                                      |
| - a lack of any abnormal plant interfacing systems behavior, and             |
| - the evolution was consistent with his understanding of the pressurizer     |
| level behavior when filling shutdown cooling piping based on his observation |
| in the past.                                                                 |
|                                                                              |
| A subsequent activity of placing shutdown cooling on line later that same    |
| day resulted in a similar event,                                             |
| with significantly less inventory loss.  Shutdown cooling train A was placed |
| on line the afternoon of 04/17/00.                                           |
|                                                                              |
| However, based on the results of the engineering review, the pressurizer     |
| level drop was not solely due to the fill and vent evolution of the shutdown |
| cooling system, as originally concluded.  Two hundred (200) gallons of RCS   |
| inventory was transferred inter-system during this event.  FPL has concluded |
| that this short duration, operator-terminated event met the procedural       |
| requirements for entering the emergency plan.  However, it is clear upon     |
| review of the context and intent of the emergency plan that at no time did   |
| an actual emergency or threat thereof exist.                                 |
|                                                                              |
| As provided for in NUREG 1022, "a licensee may discover that an event or     |
| condition had existed which met the emergency plan criteria, but that no     |
| emergency had been declared and the basis for the emergency class no longer  |
| exists at the time of discovery".  Based on an engineering review, FPL       |
| concludes that while initiating shutdown cooling on the A train on 04/17/00, |
| an RCS inventory transfer occurred to interfacing systems in the 2-3 minute  |
| periods associated with starting shutdown cooling.  The initial attempt to   |
| place shutdown cooling on line, and possibly a second attempt later the same |
| day, resulted in leakage exceeding the Technical Specification threshold and |
| would constitute entry into a Notification of Unusual Event.  Although the   |
| criteria was met, FPL is not declaring an emergency for the following        |
| reasons:                                                                     |
|                                                                              |
| 1.  The event was the result of a planned activity and the greater than      |
| expected pressurizer level drop was quickly compensated for by operator      |
| actions.                                                                     |
|                                                                              |
| 2.  The event was of very short duration and at no time challenged the       |
| ability for decay heat removal or posed a threat to the health and safety of |
| the public or plant personnel.                                               |
|                                                                              |
| 3.  The circumstances associated with determining the appropriate            |
| classification of the event required three days of engineering evaluation.   |
|                                                                              |
| State and local county officials and the Senior NRC Resident Inspector are   |
| being informed of the event.                                                 |
+------------------------------------------------------------------------------+

+------------------------------------------------------------------------------+
|Power Reactor                                    |Event Number:   36911       |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
| FACILITY: LIMERICK                 REGION:  1  |NOTIFICATION DATE: 04/20/2000|
|    UNIT:  [1] [] []                 STATE:  PA |NOTIFICATION TIME: 20:29[EDT]|
|   RXTYPE: [1] GE-4,[2] GE-4                    |EVENT DATE:        04/20/2000|
+------------------------------------------------+EVENT TIME:        19:30[EDT]|
| NRC NOTIFIED BY:  DOUG AMTHFIELD               |LAST UPDATE DATE:  04/20/2000|
|  HQ OPS OFFICER:  DICK JOLLIFFE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          N/A                   |JOHN WHITE           R1      |
|10 CFR SECTION:                                 |                             |
|APRE 50.72(b)(2)(vi)     OFFSITE NOTIFICATION   |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE   |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|1     N          N       0        Refueling        |0        Refueling        |
|                                                   |                          |
|                                                   |                          |
+------------------------------------------------------------------------------+
                                   EVENT TEXT                                   
+------------------------------------------------------------------------------+
| - LICENSEE NOTIFIED NATIONAL RESPONSE CENTER AND STATE DEP OF A CHEMICAL     |
| SPILL ONSITE -                                                               |
|                                                                              |
| The licensee notified the National Response Center and the State Department  |
| of Environmental Protection (DEP) that approximately 5 gallons of a mixture  |
| of sulfuric acid and sodium hydroxide spilled from a tank truck onto the     |
| ground after a chemical reaction took place.  The spill was contained within |
| a portable dike area onsite and is being cleaned up.                         |
|                                                                              |
| The licensee plans to notify the NRC Resident Inspector.                     |
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