U-600977, Ro:On 870704,protected Area Intrusion Detection Sys Deactivated Due to Severe Weather.Compensatory Measures Not Taken Due to Personnel Safety.Util Will Review Area of Formal Communications & Take Corrective Actions

Ro:On 870704,protected Area Intrusion Detection Sys Deactivated Due to Severe Weather.Compensatory Measures Not Taken Due to Personnel Safety.Util Will Review Area of Formal Communications & Take Corrective Actions

ML20235M513
Person / Time
Site:	Clinton
Issue date:	07/11/1987
From:	Spangenberg F ILLINOIS POWER CO.
To:	Davis A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
U-600977, NUDOCS 8707170219
Download: ML20235M513 (3)

Text

{{#Wiki_filter:-

                                                                                                                      'brYL6'
      ,                                                                                            .U-600977 1A.120 ILLINOIS POWER COMPANY CLINTON POWER STATION. P.O. BOX 678, CLINToN, ILLINOl$ 61727
                                                                                                                          ~

July 11, 1987 gienity ROUT 1 6 F Docket No. 50-461 -{- Mr. A. B. Davis v ' , h;ph;M  ; . Regional Administrator g j Region III J U.S. Nuclear Regulatory Commission  ; 799 Roosevelt. Road l Glen Ellyn, Illinois 60137

Subject:

Five-Day Report, Loss of Perimeter Detection , Incident of July 4, 1987,-Incident 008/87 i

Dear Mr. Davis:

Please find attached, for your information, the Five-Day Report on the Loss of Perimeter Detection Incident (Number 008/87) of July. 4, 1987 This report is being submitted in accordance with-10CFR73.71(c). j i If you have any questions, please contact me. Sincerely yours, [ i C '

                                                                     &M               V F. A. E angeberg'I L                                                    ,

Manager - Licensing and Safety j l JAB /cke Attachment ' cc without attachments:  ! B. L. Siegel, NRC Clinton Licensing Project Manager l NRC Resident Inspector  ; Illinois Department of Nuclear Safety

                                                                                                                              .I i

8707170219 070711 t PDR ADOCK 05000461 l S PDR , t j. SL *j h T 2p/ !

       ~

4 Attachment Illinois Power Company Clinton Power Station i Incident ) At approximately 1520 hours, on July 4, 1987, the protected area j intrusion detection system was deactivated due to severe weather. Compensatory measures were not taken due to personnel safety in that I three tornados had been sighted aloft. The protected area perimeter was j fully compensated at 1550 after the tornado warning was cancelled at 1545, i N Chronology of Events At approximately 1500 hours, the Shift Captain observed the sky becoming  ; very dark with visible lightning bolts. The Captain contacted the j Operations Lieutenant and instructed that the perimeter be posted in j accordance with Post Standing Order 45 (PS0-45), Central Alarm ' l Station / Secondary Alarm Station (CAS/SAS) Operations. At approximately 1509 hours, the perimeter was posted in anticipation of severe weather. At approximately 1510 hours, a CAS Operator received a phone call from 3 the Staff Assistant Shift Supervisor (SASS). The SASS stated that three (3) funnel clouds had been sighted alof t near Latham, Illinois; they were traveling northeast towards the plant and the area was under a l severe thunderstorm warning. The Shift Liaison instructed the CAS/SAS lead to contact the Local Law Enforcement Agency (LLEA) DeWitt County Sheriff, to try to obtain more information that could be forwarded to the Main Control Room (MCR). The CAS/SAS lead instructed the SAS operator to contact the LLEA. The < LLEA reported a funnel cloud warning due to the three tornados spotted l l over Latham. The SAS operator reported this to the CAS/SAS lead. The CAS/SAS lead reported to the Shift Liaison that the area was now ' under a tornado warning. At approximately 1513 hours, the Shift Liaison advised the Shift Captain that a tornado warning had been issued and personnel should be pulled from the compensatory posts immediately. At this time, the perimeter intrusion detection system was still active. At approximately 1519 hours, all compensatory posts had been pulled with three additional Security Force Members (SFMs) assigned in the CAS and three addi.ional SFMs assigned to the SAS to monitor the Closed Circuit Television (CCTV). Ar : approximately 1520 hours, after the six additional SFMs were in place, the intrusion detection system was deactivated.

     .                                                                                                                            l
   ,                                                                                                                              l Attachment                                                                           j Illinois Power Company                                                                        l Clinton Power Station                                                                       j l

As a result of a lightning strike near Multiplexer 5 (MUX 5), all f supervisory alarm points associated with MUX 5 on the perimeter were locked in. 1 .: At approximately 1545 hours, the CAS/SAS lead advised the Shift Liaison i that the tornado warning had been cancelled.- ] l By 1550 hours, the protected area perimeter was properly compensated. l . i The perimeter remained under compensatory measures until the supervisory alarms were cleared by Control and Instrumentation Technicians at approximately 1200 hours on July 5, 1987. Corrective Actions Since actions taken were appropriate to protect personnel safety, no corrective actions are necessary. However, due to the confusion created by interchanging the terms " funnel cloud" and " tornado, Illinois Power will review the area of formal communications and take corrective actions as appropriate. Conclusion Illinois Power considers this incident to be a moderate loss of physical  ! security effectiveness. 1

                                                                            - - - _ _ _ _ _ _ _ - - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _}}