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| Discovered date | Reporting criterion | Title | Event description | |
|---|---|---|---|---|
| ENS 46593 | 4 February 2011 21:00:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Loss of Emergency Response Data System Due to Planned Replacement of Plant Process Computer | The implementation of a planned replacement of the Unit 3 plant process computer, also known as the Critical Function Monitoring System (CFMS), with a new Plant Integrated Computer System (PICS), resulted in the loss of the Emergency Response Data System (ERDS). The Meteorological Radiological Plant Data Acquisition System (MRPDAS), and Meteorological Information and Dose Assessment System (MIDAS) is also impacted. MIDAS will function but the automatic download of Unit 3 plant parameters will not be available and the MIDAS Operator (SM or Dose Assessor) will have to manually input this data to perform dose assessment. Meteorological data will remain available. All Unit 2 functions remain available. Other systems such as the Safety Parameter Display System (SPDS), the Radiological Emergency Communication System (RECS), and the Emergency Notification System (ENS) remain available. As a compensatory measure, a proceduralized backup method is available to FAX applicable data for ERDS and MRPDAS. As discussed in a letter to the NRC data October 6, 2010, the plant process computer is being replaced due to obsolescence. The new Unit 3 computer processors will be located in the Unit 2 Computer Room which will become the Computer Room for both the Unit 2 and Unit 3 Plant Computers. The new Unit 3 plant process computer work stations will be located in the Unit 3 Control Room. The new PICS was previously installed in the Unit 3 plant simulation facility. The modification was initiated on February 4, 2011 and is scheduled to be completed by March 6, 2011. The new PICS will not affect the transmitted data points nor affect the transmission format and computer communication protocol to ERDS. In accordance with the site reporting procedure, a loss of ERDS is reportable as a major loss of emergency assessment capability. The licensee expects the duration of the ERDS outage to be from one to three weeks. The licensee notified the NRC Resident Inspector. The licensee also notified the following: New York State, Putnam County, Westchester County, Rockland County, and Orange County.
This notification is an update to the information previously provided on February 4, 2011. The replacement of the Unit 3 plant process computer with a new plant integrated computer system (PICS) has been completed. With the return of PICS to service the function of ERDS was also returned to service. A quarterly test with the NRC on April 5, 2011, verified ERDS is functional. The link to PICS for MRPDAS and MIDAS remains unavailable. The previously reported compensatory measure using a proceduralized backup method remains available to FAX applicable data for MRPDAS. Future upgrades will address the PICS data for MRPDAS and MIDAS. The licensee notified the NRC Resident Inspector and will notify the state and local authorities. Notified the R1DO (Henderson). |
| ENS 45718 | 23 February 2010 06:00:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Erds Not Availble Due to Plant Computer Malfunction | The Emergency Response Data System (ERDS) link from the Critical Function Monitoring System (CFMS) was lost at approximately 0100 hours on February 23, 2010 due to a malfunction of the plant computer. Other systems such as Safety Parameter Display System (SPDS), RECS, and ENS remain available. In accordance with the site reporting procedure, a loss of ERDS for greater than 16 hours is reportable as a major loss of emergency assessment capability. Troubleshooting is in progress. The licensee has notified the NRC Resident Inspector and will notify the state.
ERDS was restored to operable status at 1652 EST. The licensee notified the NRC Resident Inspector. |
| ENS 41958 | 29 August 2005 17:45:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Safety Parameter Display System and Emergency Response Data System Planned Upgrade Outage | On August 29, 2005 at about 1045 PDT, San Onofre Nuclear Generating Station, Unit 3, removed a portion of the Safety Parameter Display System (SPDS) and the Emergency Response Data System (ERDS) from service for a planned upgrade to ensure long-term reliability and improve the human-machine interface. This work is expected to complete within seven days. The SPDS emergency assessment function at San Onofre is implemented by a combination of the Qualified Safety Parameter Display System (QSPDS) and the Critical Function Monitoring System (CFMS). The QSPDS portion, which provides emergency assessment capability to plant operators in the control room, will remain functional. The CFMS portion, which receives input from the QSPDS, implements the ERDS and communicates data to the Technical Support Center and Emergency Offsite Facility. Only the CFMS and ERDS are impacted by this upgrade. This planned CFMS outage is being reported in accordance with10CFR50.72(b)(3)(xiii) as a courtesy notification even though only a portion of the SPDS will be removed from service and preplanned compensatory measures will be in place for the duration of the work. "At the time of this report, Unit 2 and Unit 3 were operating at about 99 percent and 100 percent power, respectively. The NRC Resident Inspectors will be notified of this occurrence and will be provided with a copy of this report. * * * UPDATE ON 09/04/05 AT 0249 FROM C. WILLIAMS TO P. SNYDER * * * The CFMS upgrade work was completed on September 3, 2005 at 2255 PDT. The SPDS and ERDS have been returned to service. The NRC Resident Inspectors will be notified of this occurrence. Notified R4DO (Smith). |
| ENS 41477 | 9 March 2005 08:00:00 | 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness | Planned Loss of the Emergency Response Data System | The following information was obtained from the licensee via e-mail (licensee text in quotes): On Thursday, March 10, 2005 San Onofre Nuclear Generating Station, Unit 2, will remove a portion of the Safety Parameter Display System (SPDS) and the Emergency Response Data System (ERDS) from service for a planned upgrade to ensure long-term reliability and improve the human-machine interface. This work is expected to complete within seven days. The SPDS emergency assessment function at San Onofre is implemented by a combination of the Qualified Safety Parameter Display System (QSPDS) and the Critical Function Monitoring System (CFMS). The QSPDS portion, which provides emergency assessment capability to plant operators in the control room, will remain functional. The CFMS portion, which receives input from the QSPDS, implements the ERDS and communicates data to the Technical Support Center and Emergency Offsite Facility. Only the CFMS and ERDS are impacted by this upgrade. This planned CFMS outage is being reported in accordance with 10CFR50.72(b)(3)(xiii) as a courtesy notification even though only a portion of the SPDS will be removed from service and preplanned compensatory measures will be in place for the duration of the work. At the time of this report, Unit 2 and Unit 3 were operating at about 79 percent and 99 percent power, respectively. The NRC Resident Inspectors will be notified of this occurrence and will be provided with a copy of this report. Should an emergency event occur, the licensee intends to transmit emergency response data to the NRC via facsimile and voice via the emergency notification system. No electronic data will be sent to the NRC Operations Center for the outage duration.
The CFMS upgrade work was completed on March 17, 2005 at 2310 PST. The SPDS and ERDS have been returned to service. The licensee has notified the NRC Resident Inspector. Notified R4DO (Farnholtz). |