QUATERLY_REPORT_2010_01_events_shortlist

Document Sample
QUATERLY_REPORT_2010_01_events_shortlist Powered By Docstoc
					                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
        SOURCE OF INFORMATION

http://www.na-sa.com.ar/news/detail
                www.arn.gov.ar
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
SOURCE OF INFORMATION

http://www.anra.am/index.asp
      http://www.anpp.am
                        DATE OF
COUNTRY   NPP UNIT                  EVENT DATE
                       REPORTING


BELGIUM    DOEL 1       1/15/2010    1/13/2010




BELGIUM    DOEL 1       2/12/2010    2/8/2010




BELGIUM   DOEL 1 & 2    3/9/2010     3/4/2010




BELGIUM   TIHANGE 2     3/23/2010    3/16/2010
                                              EVENT DESCRIPTION

      Non-compliance with Doel unit 1 valves tightness criteria - During the yearly outage of Doel Unit 1, some
   containment penetration valves were found to be exceeding the thightness criteria. The corrective actions were
     immediately implemented. This event had no consequences on health and safety of staff, population and
                                       environement, neither on the facility.

                                             Unexpected fans switch off.
  During the Doel unit 1 yearly outage, a test pointed out that an electrical protection could cause some fans to be
unexpectedly switched off. The corective actions has been implemented. Following analysis, this event was rated by
FANC at INES level 1. This failure had no consequences on health and safety of staff, population and environement,
                                                neither on the facility.
                                  Failure of an electrical protection of Doel 1 and 2.
 During a test in Doel units 1 and 2, an electrical protection of a pump motor was found not complying with all the
  specifications. As a result, the operability of the pump could be impaired in case of earthquake. The corrective
measures have been carried out. This deviation had no consequences on staff, public, environment or the facilities.
An engineering review of the EDG has pointed out that the seismic qualification of an electronic card used in a motor
start-up mode was not established. This deviation could question the operability of the EDGs in some conditions. The
 start-up mode was immediately repaired. After FANC and BelV analysis, this event has been rated at INES level 1.
 INES
             REMARKS, NOTES
SCALE


  1     Source of information in French




  1     Source of information in French




  1     Source of information in French




  1     Source of information in French
                          SOURCE OF INFORMATION


http://www.fanc.fgov.be/fr/news/depassement-criteres-d-etancheite-de-vannes-doel-
                                   1/265.aspx




     http://www.fanc.fgov.be/fr/news/arret-injustifie-de-ventilateurs/282.aspx




http://www.fanc.fgov.be/fr/news/anomalie-sur-une-protection-electrique-de-doel-1-
                                   2/289.aspx



http://www.fanc.fgov.be/fr/news/centrale-nucleaire-de-tihange-2-anomalie-classee-
                      au-niveau-1-de-l-echelle-ines/292.aspx
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
              SOURCE OF INFORMATION

                  http://www.cnen.gov.br
http://www.eletronuclear.gov.br/noticias/busca_noticias.php
                         DATE OF      EVENT
COUNTRY     NPP UNIT
                        REPORTING     DATE



BULGARIA   KOZLODUY 6    3/22/2010   3/21/2010
                                               EVENT DESCRIPTION

   On 21.03.2010 Unit 6 operates on 100% of the nominal power. The equipment works in accordance with the
 requirements for this level of power. At 23:03 the turbine-generator No 10 disconnects from the national electric
power grid due to short circuit, which led to a false signal for axial displacement of the turbine shaft. The automatic
  system for decreasing of the reactor power actuates as required. The fast acting steam dump system opens in
accordance with the design algorithm. The pressure in steam generator No 3 drops down and the reactor SCRAM
system actuates. At 23:30 the reactor was shut down in accordance with the Technical Specifications of the Unit 6.
 INES   REMARKS,
                           SOURCE OF INFORMATION
SCALE    NOTES


          Source of
                         http://www.bnra.bg/bg/facilities/npp-
  0     information in
                             events/facilities/npp-events/
          Bulgarian
                            DATE OF
COUNTRY     NPP UNIT                    EVENT DATE
                           REPORTING




CANADA    BRUCE A UNIT 1    1/21/2010    11/28/2009




                            2/19/2010




                            3/11/2010




                            3/19/2010




                            1/7/2010



                            3/17/2010




                            1/22/2010




                            2/17/2010
3/12/2010




3/22/2010
                                            EVENT DESCRIPTION

   On January 7, 2010, Bruce Power informed the CNSC of the discovery of alpha contamination in Bruce A
  Unit 1. Bruce A Unit 1 is currently shut down for refurbishment. Workers were grinding feeder tubes and a
    routine airborne survey detected alpha contamination within the work area. Alpha contamination can be
       hazardous if particulates are inhaled or ingested, which may have been the case here. Preliminary
     monitoring of all potentially affected workers indicated no overexposures.Bruce Power conservatively
reported the situation to CNSC since the preliminary monitoring indicated that an action level may have been
 exceeded. Bruce Power has arranged for more sensitive testing to be done by a third-party firm, the results
 UPDATE: On November 28, 2009, routine airborne surveying at the Bruce Nuclear Power Plant Unit 1, which
is undergoing refurbishment, detected elevated radiation (alpha) contamination. Bruce Power took measures
   to identify and contain the contamination. All regulatory requirements, including reporting requirements,
     were met. Preliminary monitoring of affected workers indicates no exposures above regulatory limits.
     However, increased monitoring of affected workers and a root cause investigation continues by Bruce
     Power. CNSC on-site staff has been actively monitoring the situation since its onset. Bioassay sample
  analysis of the potentially most affected workers indicates doses received are well below regulatory limits.
  Bioassay sample analysis on other potential workers is underway. The final results are expected in June.
UPDATE:Bruce Power has released the latest results of its dose monitoring of workers affected by the alpha
contamination event that took place in November 2009. None of the individuals tested to date have exceeded
      CNSC’s annual or five-year regulatory dose limits. The CNSC has worked with Bruce Power who has
 identified an additional lab to help expedite sample analysis. This is expected to double the rate of bioassay
     testing within a few weeks. The CNSC continues to monitor the situation and Bruce Power’s remedial
                           activities. There is no risk to the public or the environment.
   UPDATE: Bruce Power has released additional information regarding the alpha contamination event that
took place in November 2009. One individual, combined with the worker’s 2009 exposure from other sources,
 could potentially exceed CNSC’s annual regulatory dose limit. The CNSC has approved the use of alternate
 alpha dosimetry labs to increase the throughput and timeliness of communicating results to employees and
contractors. The CNSC continues to monitor the situation and Bruce Power’s remedial activities. There is no
                                    risk to the public or the environment.

  See complete event description, consequences, actions in Preliminary Report by Bruce Power in the link
                                                  PDF

  UPDATE: See complete additional information on event description, consequences, actions in Additional
                         Information Report by Bruce Power in the link PDF
 Canadian nuclear regulators say an incident of alpha contamination was fully contained within unit 1 of the
    country's Bruce A nuclear plant and there was no risk to the public or the environment. The Canadian
 Nuclear Safety Commission (CNSC) said it was told of the discovery of alpha contamination by plant owner
Bruce Power on 7 January 2010. The unit, a 750-megawatt pressurised heavy water reactor in the province of
    Ontario, has been in long-term shut-down since 1997 and is undergoing refurbishment. Workers were
grinding feeder tubes when a routine airborne survey detected alpha contamination within the work area, the
 CNSC said. Alpha contamination can be hazardous if particulates are inhaled or ingested, which may have
  been the case here, the CNSC added. However, preliminary monitoring of most of the potentially affected
workers indicated no overexposures. The CNSC said Bruce Power has arranged for "more sensitive testing"
  Analysis is under way into contamination at Bruce A nuclear power plant which could have affected up to
 217 workers. There was no impact outside plant buildings and nobody is known to have been hurt by the
    contamination during maintenance work, but Bruce Power has notified the Canadian Nuclear Safety
Commission early because the incident could receive substantial media coverage or have high visibility. As
 part the refurbishment of unit 1 in late November last year, corrosion products containing cobalt-60 were
dislodged during grinding work on reactor feeder pipes. The immediate response was to reinforce radiation
 controls and increase the frequency of sampling. Follow-up analysis confirmed the presence of cobalt-60
 and alpha-emitting contamination and this was confirmed by outside experts in late December. Radiation
  doses to all nuclear power plant workers are logged every day and Bruce Power did not mention to the
Bruce Power is conducting checks on 192 staff that could have been affected by a contamination incident in
November last year. Chalk River Laboratory has so far carried out 39 large volume bioassays with the results
  that ten people have shown less than detectable activity (MDA); 20 have more than MDA but less than 10
 mSv; six are between 10 and 20 mSv and three are between 20 and 30 mSv. None of these results has taken
 a worker beyond annual or five-year dose limits. An American lab will soon begin contributing to the work,
 following approval from the Canadian Nuclear Safety Commission, which expects the move "to double the
   rate of workers exposed to contamination during refurbishment of Canada's Bruce A nuclear power plant
One of thebioassay testing within a few weeks." Bruce Power is complementing the survey with 'extent-of-
 in November could potentially exceed the annual regulatory dose limit. Additional information released by
Bruce Power to the national regulator, the Canadian Nuclear Safety Commission (CNSC), has shown that for
  one individual, the contamination, combined with the worker's 2009 exposure from other sources, could
    potentially exceed CNSC's annual regulatory dose limit. The contamination occurred when corrosion
products containing cobalt-60 were dislodged during grinding work on reactor feeder pipes. The presence of
cobalt-60 and alpha-emitting contamination was confirmed by outside experts in late December. Since then,
 Bruce Power has been conducting checks on 192 staff that could have been affected by the contamination
 INES
        REMARKS, NOTES
SCALE
                      SOURCE OF INFORMATION




http://www.nuclearsafety.gc.ca/eng/mediacentre/updates/bruce_power_alpha
                     _contamination_jan21_2010.cfm




http://www.nuclearsafety.gc.ca/eng/mediacentre/updates/bruce_power_alpha
                 _contamination_update_feb19_2010.cfm




http://www.nuclearsafety.gc.ca/eng/mediacentre/updates/bruce_power_alpha
                _contamination_update_march11_2010.cfm




http://www.nuclearsafety.gc.ca/eng/mediacentre/updates/bruce_power_alpha
                _contamination_update_march19_2010.cfm




      http://www.brucepower.com/uc/GetDocument.aspx?docid=2954



      http://www.brucepower.com/uc/GetDocument.aspx?docid=2974




          EMAIL NucNet News in Brief / No. 12 / 22 January 2010




                     http://www.world-nuclear-
   news.org/RS_Bruce_Power_looks_into_contamination_1702101.html
                http://www.world-nuclear-
news.org/IT_Assessments_continue_at_Bruce_1203101.html




         http://www.world-nuclear-news.org/RS-
One_Bruce_worker_potentially_over_dose_limit-2203108.html
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE

 NOTHING FOUND
          SOURCE OF INFORMATION

http://www.caea.gov.cn/n602670/n621894/index.html
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
SOURCE OF INFORMATION

http://www.sujb.cz/?r_id=26
                         DATE OF
COUNTRY    NPP UNIT                  EVENT DATE
                        REPORTING




FINLAND    LOVISA 2      2/19/2010    1/3/2010




FINLAND   OLKILUOTO 2    3/12/2010    1/21/2010




FINLAND    LOVISA 1      3/31/2010    3/30/2010
                                        EVENT DESCRIPTION

Leakage of 15 m3 in the Nuclear Intermediate Component Cooling system (TF) in one instrumentation
   room below the auxiliriary control room. Cause: Break of the V-belt of the cooling device in the
Ventilation System for Controlled Zone (TL) together with cold air coming from the exhaust air line of
 the chiller resulted in the brokage of the condensator of the chiller resulting the leakage of the water
from the chiller and TF system. No harm to the cables affected by the flooding; cables were designed
    for accident conditions or the manufactuer confirmed their resistance against the experienced
               conditions. The event was reported to STUK with a operational event report.


  Faulty spare voltage regulator for diesel generator. During a trial test in periodic maintenance of one
    DG faulty volatge regualtor was identified. The regulators served over 10 years were decided to
     replace with new ones. During the replacement of the voltage regulator of one DG (preventive
   maintenance package) in January 2010, two spare voltage reglators were found faulty. All volatge
regulators in the spare part storage have been sent to the manufacturer for futher testing. The common
   cause failure has already been excluded due to the proper function of four spare regulators. The
 conprehensiveness and adequacy of testing requiremenst will be assessed. The case will be followed
                                        by the licensee and STUK.


Leakage of radioactive waste water to the ventilation system for controlled zone (TL). The leakakge of
 radioactive water (70 - 100 litres) containing resin was found from the ventilation duct. The water was
 the origin of the gas exhaust pipe of one resin mixing tank in the Solid active waste treatment system
  (TT). During the day the flushing operations of resin tanks (two) were carried out, and due to a faulty
level measurement one resin tank was overfilled resulting in the overflow to the gas exhaust pipe. The
   leagake was identified rapidly due to other maintenance activities going on in the room. Preliminary
                      INES estimation was 0. STUK consider the event as INES 1.
 INES
             REMARKS, NOTES
SCALE




         Flooding contributed by cold
             wheather conditions




         Adequacy of requirements for
        testing procedure of equipment.




          Component failure, human
  1
               performance
              SOURCE OF INFORMATION




    Operational Event Report for information to STUK




Operational Event report submitted to STUK for information.




  Operational Event report has been submitted to STUK.
                Special Report will follow.
        A           B              C            D                                                                                                                                                                        E                                                                                                                                                                   F                                    G                                                                        H
                               DATE OF                                                                                                                                                                                                                                                                                                                                                      INES
     COUNTRY     NPP UNIT                  EVENT DATE                                                                                                                                                        EVENT DESCRIPTION                                                                                                                                                                                          REMARKS, NOTES                                                       SOURCE OF INFORMATION
1                             REPORTING                                                                                                                                                                                                                                                                                                                                                    SCALE


                                                         On December 15th 2009, the Cruas NPP reported that an EDG of unit 4 failed to be started up from the Control Room. On December 3rd, during a periodic test, an operator mistakenly put a switch in an improper position, which didn't allow the diesel to be started up from the Control Room. If the EDG start-up had
     FRANCE      CRUAS 4       1/6/2010     12/15/2009   been needed, it could have been done only in the EDG Room, which would have delayed the power back-up by this diesel. Nevertheless, the other EDG remained operable and could have supplied power if it had been needed. On December 7th, this deficiency was found out and immediately repaired.                                   1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/108276
                                                         This event didn't have any consequences for environment or staff safety but led to a breach of the TS, as the EDG was inoperable during longer than authorized, and the event was thus rated at INES level 1.
2
3

                                                         On December 18th 2009, the operating range of Cruas unit 1 had been exceeded during 2 minutes. Following a dilution of the Reactor Coolant System boron, the RCS temperature was found to be exceeding the TechSpec upper limit and therefore the reactor was out of its operating range. This was caused by
                                                         unsufficient surveillance by the operators.
     FRANCE      CRUAS 1       1/6/2010     12/18/2009                                                                                                                                                                                                                                                                                                                                       1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/108273
                                                         The operating procedures have been immediately implemented, which allowed the RCS temperature to come down inside the operating range.
                                                         This event had no consequences on facilities, environment or staff, but in reason of the breach of TechSPec, it was rated at INES level 1.
4
5
                                                         On July 12th 2009, the Saint-Alban NPP informed ASN that tightness seals repair works in Unit 1 caused a large volume of air to enter into the suction pipes of Safety Injection System and Containment Spray System pumps. As a result, those pumps had been declared inoperable.
                                                         During the first half of 2009, the utility replaced some seals on these systems pipes, which caused air to come inside the pipes. The pipes venting didn't allow to remove all the air.
                                                                                                                                                                                                                                                                                                                                                                                                   Source of information in French. Info notice on the subject by   http://www.asn.fr/index.php/content/view/full/108282; http://www.nrc.gov/reading-
     FRANCE     ST-ALBAN 1     1/7/2010     12/28/2009   If the SIS and CSS had been required, the air could have reduced the pumps performance or even caused the pumps to stop and to be damaged.                                                                                                                                                                                          1
                                                                                                                                                                                                                                                                                                                                                                                                                    NRC in 2006, see PDF link.                                rm/doc-collections/gen-comm/info-notices/2006/in200621.pdf
                                                         The Saint-Alban NPP detected this deficiency during operating tests in July 2009 and took immediately corective actions to remove the air.
6                                                        This event had no consequences on environment or staff safety. This event was first rated at INES level 0 but, upon ASN request, EDF has continued the safety analysis of this event. Finally, on December 28th, this event has been rated at INES Level 1 because of TEchSpec breaches.
7
                                                         On September 30th 2009, EDF reported a deficiency related to the greasing of the RHR system motor-driven pumps. This deficiency concerned the Blayais units 1,2,3 and 4, the Gravelines unit 1, the Tricastin units 1,2,3 and 4, the Nogent unit 1, the Penly units 1 and 2 and the Civaux unit 2.
                                                         During maintenance activities, different kinds of greases were found mixed in the motor-driven pumps, which could question the Environmental Qualification of the pumps. Indeed, even if each individual grease is qualified, there is no evidence of EQ of the greases mix.
     FRANCE      GENERIC       1/12/2010    9/30/2009                                                                                                                                                                                                                                                                                                                                        1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/108333
                                                         EDF has conducted a verification and repair programme which has been controlled by ASN during the units outages.
8                                                        Because the feedback of similar events in April 2001 and July 2009 has not been implemented, this deficiency has been rated at INES level 1.

9
                                                         On October 16th 2009, EDF reported a generic deficiency related to the head bearings of the connecting rods of EDG motors, concerning the Blayais units 1and 3, Bugey units 2, 3 and 4, Chinon unit B3, Cruas units 3 and 4, Saint-Laurent unit 2 and Tricastin units 1, 2, 3 and 4.
                                                         Following a failure of an EDG in Chinon unit B4 in July 2008, an investigation was carried out by EDF and the motor vendor. This investigation revealed in October 2009 that a fast deterioration of a bearing caused the deficiency. When the diesel engine is operating, the bearing deterioration could cause the engine to
     FRANCE      GENERIC       1/27/2010    10/16/2009   seize up and therefore the EDG to fail.                                                                                                                                                                                                                                                                                             1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/108702
                                                         In October 2009, EDF conducted a bearings replacement programme. The event was first rated at INES level 0 on October 19th 2009 according to the information available at the moment. After replacement of the bearings, a further investigation revealed a potential failure of the bearings for one of the both EDGs of
                                                         each concerned unit, leading therefore the event to be rated at INES level 1 on Jannuary 14, 2010.
10
11
                                                         On January 15th 2010, EDF found out a deviation from the procedure of a periodic test which was carried out on December 18th 2009. This test concerns the in-core reactor power measurement and it was found out that 2 thermocouples were checked beyond the TechSpec time limit.
                                                         Following failures of thermocouples which are taking part in the post-accident surveillance system, thermocouples have been swapped for years in Paluel units. In some case, thermocouples taking part in the post-accident surveillance system have been swapped for nearby thermocouples. In Paluel unit 1, 2 out of
                                                         the 22 thermocouples taking part in the post-accident surveillance system have been swapped.
     FRANCE      PALUEL 1      1/27/2010    1/15/2010    On December 18th 2009, when the thermocouples taking part in the post-accident surveillance system were tested, the thermocouples swapping was missed and, as a result, the 2 swapped thermocouples were not tested.                                                                                                                1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/108693
                                                         On January 15th 2010, the miss was detected. The 2 missed thermocouples were tested and found to be in compliance with the expected performance.
                                                         Similar events already occured in Paluel NPP in 2004, 2005 and 2009.
12                                                       This deviation hasn't had any consequences on nuclear safety, staff safety or environment. Nevertheless, as it had already happened several times, the event was rated at INES level 1.
13

                                                         On January 20th 2010, during a periodic test, a pump of the Coolant Water Pumps Seals Injection System was found to be out of the expected operating range. The pump was immediately declared to be inoperable and, in compliance with the TechSPec, the reactor has been shutdown. The cause of the failure was
     FRANCE      PALUEL 2      2/1/2010     1/20/2010                                                                                                                                                                                                                                                                                                                                        1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/108718
                                                         investigated and repaired by the utility. This event had no consequences on staff or environment. Nevertheless, as a pump involved in the primary containment was inoperable, the event was rated at INES Level 1.
14
15
                                                         On January 25th 2010, the Bugey NPP reported that the upper limit of the Reactor Coolant System temperature had been exceeded.
                                                         On January 21st 2010, while the unit 4 was starting up, a failure of the steam pressure regulation system caused the RCS temperature to increase slightly over the TechSpec upper limit (289 C). The RCS temperature had been fluctuating around 289 C during 2 hours but never exceeded 289,3 C. The late detection
     FRANCE      BUGEY 4       2/12/2010    1/25/2010    of this TechSpec breach didn't allow to have the temperature quickly decreased within the TechSpec range.                                                                                                                                                                                                                           1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/108988
                                                         This event had no consequences on facilities, environment or staff.
16                                                       Because of the TechSpec breach, the event was rated at INES Level 1.
17
                                                         On February 3rd 2010, the Bugey NPP reported a mounting deficiency of a Containment Spray System valve. On February 1st, during a CSS periodic test, a valve position indicator was found to be mis-mounted : the valve was indicated to be closed when open and open when closed. This deficiency was immediately
                                                         repaired.
     FRANCE       BUGEY        2/17/2010     2/3/2010                                                                                                                                                                                                                                                                                                                                        1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/109178
                                                         This event had no consequences on facilities, environment and staff.
18                                                       Because of the TechSpec breach, the event was rated at INES Level 1.
19

                                                         On October 2nd 2009, while the Dampierre unit 3 was starting up, a Main Steam Isolation Valve was detected uncompletely closed, in deviation from the TechSpec. This failure was due to the mounting of an improper spare part during maintenance in 2008. This spare part was intended for another reactor design.
     FRANCE    DAMPIERRE 3     2/18/2010    10/2/2009    Upon ASN request, the improper part has been replaced and the EDF Headquarters which caused the spare parts identification mistake, have reported a generic event. As no leakage occured from the primary circuit to the secondary circuit, radioactivity remains inside the primary circuit and the event had no                   1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/109192
                                                         consequences on the environment. Because of the TechSpec breach, the event was rateed at INES Level 1.
20
21
                                                         On October 29th, during the outage of unit 4, the Bugey NPP reported that a containment penetration valve was found open, whereas it was requested to be closed by the TecSpec.
     FRANCE      BUGEY 4       2/19/2010    10/29/2009   The valve was closed immediately.                                                                                                                                                                                                                                                                                                   1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/109277
                                                         This deviation had non consequences on staff or environment. Nevertheless, because of the TechSpec breach, the event was rated at INES Level 1.
22
23
                                                         During the outage of Chooz unit B2 from March to April 2009, the utility carried out maintenance activities on 8 Auxiliary Feedwater valves pneumatic actuators.
                                                         On February 19th 2010, during the same maintenance activity on unit B1, the utility found out that the commissioning of the AFW of unit B2 hadn't been properly performed after maintenance. Mainly, the hydraulic resistance of AFW injection pipes hadn't been checked. The utility immediateley checked the hydraulic
     FRANCE     CHOOZ B2       2/25/2010    April 2009   resistance of the unit B2 pipes, which led the settings of 5 out of the 8 valves to be modified.                                                                                                                                                                                                                                    1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/109330
                                                         This event had no actual consequences. Nevertheless, in case of a main feedwater pipe break, the Steam Generators auxiliary feedwater flow could have been less than expected.
                                                         Because of the impairement of the safety system, this event was rated at INES level 1.
24
25

                                                         On January 18th 2010, while the Fessenheim unit 2 was in operation, a turbine pressure probe was found malfunctionning. This failure impaired both the reactor protection system and the condenser regulation.
     FRANCE    FESSENHEIM 2    2/26/2010    1/18/2010    Because of the improper analysis of this failure, the reactor wasn't shutdown within the TecSpec time limit. When the utility found that the analysis was not correct, the pressure probe wasn't repaired yet and the shutdown time limit was exceeded.                                                                             1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/109343
                                                         Because of the TechSpec breach, the event was rated at INES Level 1.
26
27

                                                         On March 7th, 2010, the Golfech unit 2 had been operated out of its TechSpec operation range during 43 minutes.
                                                         On March 7th, the unit 2 had just been shut down for a maintenance and refuelling outage. While RCS pressure and temperature were decreasing, a lack of surveillance by the operating shift led both pressure and temperature TechSpec limits to be exceeded.
     FRANCE     GOLFECH 2      3/16/2010     3/7/2010                                                                                                                                                                                                                                                                                                                                        1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/109623
                                                         As soon as the deviation was detected, the adequate procedures were implemented in order to comply with the TechSpec limits.
                                                         This deviation had non consequences on staff, environment or safety. Nevertheless, because of the TechSpec breach, the event was rated at INES Level 1.
28
29
                                                         On March 8th 2010, while a periodic test was going on in order to check the configuration of a set of valves, the licensee found a valve closed whereas it was requested open by the TechSpec. The valve concerned is a part of the installation which is intended to prevent the pressurization of the Safety injection valves
                                                         body, which could challenge the safety injection valves operability. The valve closure impairs the operability of one of the both safety injection trains in case of LOCA.
     FRANCE      PALUEL        3/23/2010     3/8/2010    The valve was mistakenly closed since November 6th, 2009.                                                                                                                                                                                                                                                                           1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/109755
                                                         A similar failure already occured in Paluel NPP in 2008.
30                                                       Because of the late detection of this deviation and because it has already happened, the deviation was rated at INES level 1.
31
                                                         On March 6th 2010, during a comprehensive inspection of the Environmentally Qualified servo-motors of Gravelines unit 3, a grease mix was found in some servo-motors, which questions their qualification. The concerned systems are the RHR and Reactor Coolant systems.
                                                         The grease of those servo-motors has been replaced.
     FRANCE    GRAVELINES 3    3/23/2010     3/6/2010    Those deviations, which affect other EDF NPPs, led to the declaration of a generic event on July 15th 2009 which was rated at INES level 1.                                                                                                                                                                                         1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/109758
                                                         Those deviations had non consequences on staff, environment or safety
32                                                       However, as those deviations have a common cause failure concerning the maintenance of redundant safety-related equipment, this event was rated at INES level 1 as the generic event.

33
                                                         On February 25th, 2010, the licensee of Civaux NPP found out that 8 motors bearings hadn't been greased within the required time limit. The EDF maintenance programme requires the bearings to be greased after a certain amount of operating hours, depending on the motor. The operating hours are displayed on a
                                                         counting device, they are checked periodically then manually typed. Afterwards, a software launches automatically a work order when the greasing threshold is close.
                                                         On February 25th, the maintenance dept. found out that a pump motor hadn't been greased within the required time limit because its operating hours counter was out of order. After investigation, 2 other counters were found out of order in Unit B1 and 5 in Unit B2. The concerned motors had been operating between
     FRANCE       CIVAUX       3/31/2010    2/25/2010                                                                                                                                                                                                                                                                                                                                        1                     Source of information in French                                http://www.asn.fr/index.php/content/view/full/109903
                                                         115 and 12500 hours beyond the greasing time limit. Nevertheless, the vibration records of the 8 pumps didn't show any damages.
                                                         The Techspec don't allow to grease all the concerned motors at the same time. At the moment, 3 motors bearings have still to be greased in the coming weeks.
34                                                       As the concerned motors kept running correctly, this event had no actual consequences. Nevertheless, a similar event already occured on April 24th, 2006, which led the event to be rated at INES level 1.
35
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE

 NOTHING FOUND
                                SOURCE OF INFORMATION


               http://www.enbw.com/content/de/presse/meldepflichtige_ereignisse

 http://www.rwe.com/web/cms/de/241154/rwe-power-ag/standorte/kernkraftwerke/kkw-biblis/presse-
                              betriebsinformationen/archiv-2009/
http://www.rwe.com/web/cms/de/17050/rwe-power-ag/standorte/kernkraftwerke/kkw-emsland/presse-
                                    betriebsinformationen/

                 http://www.kkw-gundremmingen.de/presse.php?Typ=Mitteilung

                  http://www.kkw-gundremmingen.de/presse.php?Typ=Ereignis

                                    http://www.schleswig-
       holstein.de/MSGF/DE/Service/Presse/PI/2009/090813__msgf__mebrunsbuettel.html

                                   http://www.vattenfall.de/
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
             SOURCE OF INFORMATION

http://www.haea.gov.hu/web/v2/portal.nsf/introduction_en
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
        SOURCE OF INFORMATION

           http://www.aerb.gov.in/
         http://www.kseboa.org/news/
http://www.npcil.nic.in/main/PressRelease.aspx
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE   EVENT DESCRIPTION
                     REPORTING

                                               NOTHING FOUND
 INES
        REMARKS, NOTES          SOURCE OF INFORMATION
SCALE

                         http://www.tepco.co.jp/en/niigata/index-e.html
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
SOURCE OF INFORMATION

http://www.kins.re.kr/english/
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE

 NOTHING FOUND
       SOURCE OF INFORMATION

   http://www.vatesi.lt/index.php?id=2&L=1
http://www.iae.lt/inpp_en.asp?lang=1&sub=234
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE

 NOTHING FOUND
               SOURCE OF INFORMATION

http://www.cnsns.gob.mx/seg_nuclear/seguridad_nuclear.aspx
              http://saladeprensa.cfe.gob.mx/
          NPP     DATE OF    EVENT
COUNTRY                              EVENT DESCRIPTION
          UNIT   REPORTING   DATE
                                      NOTHING FOUND
 INES
        REMARKS, NOTES         SOURCE OF INFORMATION
SCALE
                         http://www.vrominspectie.nl/actueel/nieuws/
                                        www.epz.nl
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
SOURCE OF INFORMATION

   http://www.pnra.org
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
          SOURCE OF INFORMATION

http://www.cncan.ro/ro/evenimente.php?page=istoric
                http://www.cne.ro/
                                  DATE OF
COUNTRY        NPP UNIT                       EVENT DATE
                                 REPORTING




RUSSIA    Volgodonsk Unit No.1    1/11/2010    1/10/2010




RUSSIA       Kola Unit No.1       2/2/2010     1/15/2010
                                             EVENT DESCRIPTION

   Unit 1 of the Volgodonsk NPP was routinely halted by the personnel for maintenance to remedy a defect in the
    steam-generator piping detected by the reactor's automatic control systems.The preliminary cause has been
 determined as a leakage in the steam generator piping. The repairs are estimated to take four days. The limits and
conditions of safe operation of equipment have not been violated. The background radiation at the Volgodonsk NPP
 and in the surrounding area corresponds to those of standard-mode reactor operation and does not exceed natural
                                                background values.




On 15.01.2010 16:48, while the plant operating capacity was 1,433 MW, the failure of the voltage transformer led to
 shutdown of two power lines 330 kV that supply electrical power from Kolsk NPP to Murmansk Oblast. Alongside
  with this, power units Nos.3 and 4 were balanced up to 50 % of continuous power in compliance with the design
algorithm. Power supply of Murmansk Oblast was renewed in 1 min 14 s; the plant load was restored to the level of
 the dispatch schedule at 20:05. Preliminary classification of the event according to INES is “below scale”. Repair
works of the failed equipment are scheduled for February 4. The accident has no impact on the safety operation of
                             the plant and stability of power supply in Murmansk Oblast.
   INES
              REMARKS, NOTES                         SOURCE OF INFORMATION
  SCALE


                                               http://www.rosenergoatom.ru/eng/press/news/
             Source of information                       http://www.gosnadzor.ru/ ;
     0
                  in Russian          http://www.rosatom.ru/ru/safety/news_yarb/index.php?from4=4;
                                                         http://www.russianatom.ru/



             Source of information
             in Russian. Results of
               investigation of the
              Inquiry Commission:
                                               http://www.rosenergoatom.ru/eng/press/news/
                 the failure of the
                                                         http://www.gosnadzor.ru/ ;
Below scale voltage transformer led
                                      http://www.rosatom.ru/ru/safety/news_yarb/index.php?from4=4;
               to shutdown of two
                                                         http://www.russianatom.ru/
               power lines 330 kW
               and damage of the
              adjacent disconnect
                      switch.
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE

 NOTHING FOUND
              SOURCE OF INFORMATION

http://www.ujd.gov.sk/ujd/web.nsf/viewByKeyMenu/En-01-01
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
SOURCE OF INFORMATION

     http://www.nek.si/
 http://www.ursjv.gov.si/en/
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
   SOURCE OF INFORMATION

        http://www.nnr.co.za/
http://www.eskom.co.za/live/index.php
                      DATE OF
COUNTRY   NPP UNIT                EVENT DATE
                     REPORTING

 SPAIN    ALMARAZ     15/2/2010    15/02/2010




 SPAIN    ASCÓ II     23/3/2010    23/03/2010
                                               EVENT DESCRIPTION

The reactor of Almaraz I NPP has tripped due to steam generator low level, during the opening of the main feedwater
                                line isolation valve, while in the process of startup.

   During the repair of a recirculation pump of the boron inyection tank, the redundant pump had to be put out of
 service. The recirculation capacity was therefore out of service longer that allowed in the Technical Specifications.
    This event has not had any impact in the status of the plant, and has not posed any risk for the public or the
                                                     environment.
 INES
             REMARKS, NOTES
SCALE

  0     Source of information in Spanish




  0     Source of information in Spanish
                                   SOURCE OF INFORMATION

          http://www.csn.es/index.php?option=com_content&view=category&id=48%3Anotas-
                            informativas&layout=blog&Itemid=121&lang=en



http://www.csn.es/index.php?option=com_content&view=category&layout=blog&id=47&Itemid=120&lang=en
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
                                   SOURCE OF INFORMATION

  http://www.stralsakerhetsmyndigheten.se/In-English/About-the-Swedish-Radiation-Safety-Authority1/
                               http://www.okg.se/default____123.aspx

http://www.vattenfall.se/www/vf_se/vf_se/518304omxva/518334vxrxv/518814vxrxe/520284ringh/index.jsp

http://www.vattenfall.se/www/vf_se/vf_se/518304omxva/518334vxrxv/518814vxrxe/519534forsm/index.jsp
                      DATE OF
COUNTRY   NPP UNIT               EVENT DATE
                     REPORTING
                     INES
EVENT DESCRIPTION           REMARKS, NOTES
                    SCALE
 NOTHING FOUND
SOURCE OF INFORMATION

http://www.ensi.ch/index.php
                               DATE OF
COUNTRY      NPP UNIT                      EVENT DATE
                              REPORTING


  UK      Torness Reactor 1   15/02/2010    1/2/2010
                                              EVENT DESCRIPTION

   Torness Reactor 1 tripped on 1 February 2010 following the failure of a generator transformer. Work has
commenced to replace the transformer and it is expected that the unit will be returned to service early in the second
                                                quarter of 2010.
 INES
        REMARKS, NOTES
SCALE
                SOURCE OF INFORMATION


http://www.edfenergy.com/media-centre/press-news/EDF-ENERGY-
                 OPERATIONAL-UPDATE.shtml
                            DATE OF
COUNTRY     NPP UNIT                    EVENT DATE
                           REPORTING


          Zaporozhje NPP
UKRAINE                    05.10.2009    04.10.2009
             Unit Nr. 3




          Zaporozhje NPP
UKRAINE                    21.10.2010    21.10.2010
             Unit Nr. 1




          Rovno NPP Unit
UKRAINE                    19.10.2009    19.10.2009
               Nr.2




          Khmelnicka NPP
UKRAINE                    02.11.2009    30.10.2009
             Unit Nr. 2




          Khmelnicka NPP
UKRAINE                    16.02.2010    16.02.2010
             Unit Nr. 2




          Khmelnicka NPP
UKRAINE                    31.03.2010    30.03.2010
             Unit Nr. 2
                                               EVENT DESCRIPTION

Energy unit was shut down in the condition "hot standby". Main circulation pump Nr.1 tripped as result of activation of
   differential protection of electric motor. During visual inspection leakage of cooling water was found at the lower
 flange of air cooling system of electric motor of MCP. Repair personnel removed hatch of electric motor and found
    charred section of stator of electric motor of MCP. There were no breaches of safety limits and conditions or
                                            radiation consequences of incident.


 Energy unit was working at nominal power (Ne=1000 MW). Main circulation pump Nr.1 tripped as result of activation
  of differential protection of electric motor. Unit power reduced to Ne=535 MW. During visual inspection leakage of
cooling water was found at the lower flange of air cooling system of electric motor of MCP-1. There were no breaches
                           of safety limits and conditions or radiation consequences of incident.



    Energy unit was working at nominal power (Ne=415 MW). Operative personnel of MCR identified increasing
humidity in the shaft of the control-protection system. During inspection of leaktight compartment leakage of coolant
from the primary circuit identified in the chamber A-201/2 near the non-return valve 2CH12-2 of standpipe 2HOP-2
of primary circuit. Estimated leakage flow rate up to 4.5 m3/day, about 3 liters per minute. Unit power reduced to 0.



Energy unit was working at nominal power (Ne=1000 MW). The scheduled maintenance according to work program
 of the 3 train of safety system was underway. After disconnection of power supply to the section 2BX, starting of
   diesel-generator and connecting them to section 2BX emergency feed water pump 2TX30D01 failed to start.
   Availability of trains TX10, TX20 was confirmed. There were no breaches of safety limits and conditions. The
         radiation background at the NPP and in the surrounding area did not change (remaining normal).



  Energy unit was working at nominal power (Ne=1010 MW). E15 During the 77 step of the working program after
 disconnection of power supply to the section 2BW diesel-generator failed to start. Availability 1of 3 trains of safety
system was confirmed. There were no breaches of safety limits and conditions. The radiation background at the NPP
                         and in the surrounding area did not change (remaining normal).


 When stable working at nominal power (Ne=1007 MW) energy unit was disconnected from grid due to actuation of
generator protection БРЕ1301against short circuit. The 750 kV switches (circuit breakers) В-31, В-32 were affected,
 and block transformer was disconnected. Signals on the control panel of MCR were activated: “Protection against
  short circuit of generator winding”, “Actuation of technological protection”. During transient process all systems
 performed as designed. There were no breaches of safety limits and conditions. The radiation background at the
                        NPP and in the surrounding area did not change (remaining normal).
 INES
              REMARKS, NOTES
SCALE



  0     Source of information in Ukranian




  0     Source of information in Ukranian




  0     Source of information in Ukranian




  0     Source of information in Ukranian




  0     Source of information in Ukranian




  0     Source of information in Ukranian
SOURCE OF INFORMATION




   http://www.npp.zp.ua




   http://www.npp.zp.ua




  http://www.snrc.gov.ua/




  http://www.snrc.gov.ua/




  http://www.snrc.gov.ua/




  http://www.snrc.gov.ua/
                                    DATE OF
COUNTRY        NPP UNIT                         EVENT DATE
                                   REPORTING




  US      Braidwood Units 1 & 2     1/11/2010   1/9/2010 19:51




  US         Catawba Unit 1         2/19/2010   2/18/2010 3:33




          Calvert Cliffs Units 1
  US                                2/19/2010   2/18/2010 8:24
                  and 2




                                    3/1/2010




  US      Davis-Besse Unit 1        3/16/2010     3/12/2010




                                    4/12/2010
                           3/18/2010




                           3/18/2010




     H. B. Robinson Unit
US                         3/29/2010   3/28/2010 18:51
              2




                           3/31/2010




                           4/19/2010




US         Perry           3/30/2010   3/28/2010 18:38
                    3/31/2010




US   Fermi Unit 2   3/30/2010   3/25/2010 16:27




                    3/31/2010
                                                EVENT DESCRIPTION

On January 9, 2010, at 7:51 p.m. CST, Braidwood Station declared a Notice of Unusual Event due to exceeding by 1
 minute the 15-minute limit for extinguishing a fire within the protected area. The fire, which originated from a bearing
    of the Auxiliary Building Ventilation Supply Fan, was extinguished in 16 minutes using portable extinguishers. No
        offsite assistance was required to support the fire fighting efforts. The licensee confirmed that the fire was
       extinguished at 7:41 p.m. CST and continued to monitor the area. There were no injuries from the event. The
    licensee terminated the Unusual Event at 9:11 p.m. CST on January 9, 2010. Both Braidwood units continued to
   operate at full power throughout the event. No other safety related equipment was affected by the fire. This fan is
 utilized by both Braidwood units. The licensee is working to determine the cause of the fire. Region III monitored the
 licensee’s responses to the event in consultation with the staff from the Office of Nuclear Reactor Regulation (NRR)
  On February 18, 2010, at 3:33 a.m., Catawba Unit 1 was shutdown to Mode 3 to allow for additional inspection of a
     reactor coolant leak. The unidentified RCS leak rate was 0.08 gpm. Initial inspection using a remotely operated
camera indicated that the leakage was coming through the insulation on the reactor coolant "A" hot leg. On February
18, 2010, at 1:48 p.m., the unit entered Mode 4. A bare metal visual inspection confirmed pressure boundary leakage
  at a seal weld on the 1A Hot Leg Wide Range RTD thermowell. No release to the environment occurred as a result
   of this leak and there is no danger to the public. The licensee made the proper notifications and entered Technical
     Specification 3.4.13, "RCS Operational Leakage." The unit entered Mode 5 on February 19, 2010, at 0223. The
   licensee plans to repair the weld, inspect the RTD thermowells on the other loops, and return the unit to power on
   Sunday, February 21, 2010. This preliminary notification is issued for information only and no further action by the
       At 8:24 a.m. on February 18, 2010, Calvert Cliffs experienced a loss of one of the two electrical power
  distribution buses for the site. Loss of this power source resulted in a Unit 2 trip and all four Unit 2 reactor
  coolant pumps (RCPs) tripping. The loss of this bus caused a loss of power to one of the two safety buses
      on each unit; the Unit 2 2B emergency diesel generator (EDG) initially started, but tripped and failed to
      supply power to the affected Unit 2 safety bus. The Unit 1 1B EDG started as expected upon the loss of
power and supplied power to the affected Unit 1 safety bus. Plant operators cross-tied the de-energized Unit
  2 safety bus with another power source to return power to Unit 2 safety-related loads. At approximately the
same time as the loss of power, Unit 1 experienced an unexpected trip of one of the RCPs, resulting in a Unit
   trip. All other preliminary notification supplements information in PNO-I-10-001, stable in hot standby. Due
1UPDATE: This safety systems responded as appropriate. Both units are currently which documented a dual
    unit reactor trip at Calvert Cliffs that resulted in a shutdown greater than 72 hours. The Unit 1 trip was
   caused by the loss of one of the reactor coolant pumps. The normal power supply to the electrical bus
 supplying the reactor coolant pump tripped due to water intrusion into the breaker cabinet. Unit 1 systems
    were subsequently cooled down and has entered a refueling outage, originally scheduled to begin on
  February 21, 2010. The Unit 2 reactor trip was the result of the loss of a 13 KV transformer, caused by the
 failure of a protective relay after the Unit 1 bus was lost. The source of the water intrusion into the breaker
   cabinet (roof leak) has been repaired, and other maintenance has been completed. The cause of the 2B
 emergency diesel generator shutdown after starting was determined to be a faulty relay and slow response
    While performing NRC required inspections on Friday, March 12, Davis-Besse Nuclear Power Station
  (DBNPS) workers identified potential cracks in some of the control rod drive mechanism (CRDM) nozzles
 inspected. At the time DBNPS was conducting planned ultrasonic (UT) examinations on the CRDM nozzles
which penetrate the reactor pressure vessel (RPV) head. The reactor is in a safe condition and has been shut
  down for a scheduled refueling outage since February 28, 2010. Additionally, during the bare metal visual
   examination of the outer surface of the RPV head, dried boron deposits were found at two of the CRDM
nozzles, which is indicative of possible primary water leakage. A visual examination and a UT examination is
being performed on the RPV head. As of March 15, 2010, the utility has completed examinations on 50 of the
 69 nozzles for the first set of planned UT examinations. When the utility is ready they will provide an action
 UPDATE: As of April 12, 2010, the utility has completed UT and BMV examinations on all of the 69 nozzles.
 On April 1, 2010, the utility submitted an action plan for the nozzle repair activities to the NRC for approval.
They plan to repair at least 16 of the 69 nozzles. On March 16, 2010, the NRC dispatched a Special Inspection
   Team to DBNPS to review the circumstances surrounding the discovery of crack indications in multiple
 CRDM nozzles and to evaluate the utility's actions to properly analyze the nature of the flaws, its proposed
repair methods, and conclusions regarding the mechanism causing the greater than expected indications of
nozzle flaws. The NRC will hold a public exit meeting when the Special Inspection is complete to discuss its
preliminary findings. The Special Inspection report will be issued 30-45 days after the exit meeting. To date,
   The US Nuclear Regulatory Commission has dispatched a special inspection team to investigate cracks
  discovered in the reactor vessel head at the Davis-Besse nuclear plant in Ohio. The 877 MWe pressurized
   water reactor (PWR) entered a refuelling and maintenance outage on 28 February, and inspections on 12
   March by operator First Energy Nuclear Operating Company (Fenoc) discovered indications of cracking
round several of the control rod drive mechanism (CRDM) nozzles, which penetrate the reactor vessel head.
 The company notified the NRC along with federal, state and local officials. Inspections including bare metal
  visual and ultrasonic testing are ongoing, although by 15 March Fenoc had tested 49 out of the 69 nozzles
    and detected indications of cracking in 12 of them. The NRC has taken pains to stress that the cracks
  present no danger to the public since the reactor is inspection an outage and will not benuclear power plant
The US Nuclear Regulatory Commission has sent an already in team to the Davis-Besse allowed to restart
    to review the circumstances surrounding the discovery of crack indications in multiple control rod drive
mechanism (CRDM) nozzles, which guide the control rods into the reactor core to shut down the reactor. The
  NRC said that on 12 March 2010, while performing NRC-required inspections of CRDM nozzles, workers at
the Ohio plant discovered preliminary indications of cracks in some of the nozzles that penetrate the reactor
vessel head. These inspections, which include bare metal visual and ultrasonic testing, are continuing. When
  the testing of the plant's 69 CRDM nozzles is complete, the utility will determine the number of nozzles that
    need to be repaired. There is no danger to the public from these cracks because the plant has been shut
down for a scheduled refueling outage. But before the plant can resume operations, the NRC said it must be
  On March 28, at 6:51 p.m., H.B. Robinson Steam Electric Plant Unit 2 experienced an automatic reactor trip
   due to an undervoltage condition on the non-safety related 4kV bus #4 and a subsequent reactor coolant
 pump trip. At 6:56 p.m. a fire was reported in the non-safety related 4kV bus #5 (which is powered from bus
#4). The licensee’s fire brigade responded and the fire in 4kV bus #5 was reported out at 7:05 p.m. Following
 the reactor trip, at 7:00 p.m., a safety injection occurred due to low pressurizer pressure caused by the post
   trip cooldown. The plant was stabilized and the licensee initiated an event response team. At 10:35 p.m. a
  loud noise and thick smoke in the non-safety 4kV bus #4 room were reported to the control room. At 11:00
 p.m. the licensee declared an Alert per Emergency Action Level HA2.1, due to a fire affecting the operability
     of plant safety systems required to establish or maintain safe shutdown. DC team to the H.B. Robinson
    The US Nuclear Regulatory Commission (NRC) has sent a special inspection bus grounds were present
 nuclear power plant in South Carolina to review the circumstances surrounding a fire in an electrical panel
  that led to an Alert being declared late on Sunday evening. An Alert is the next-to-lowest NRC emergency
  classification for plant events. The NRC said the plant experienced an automatic shutdown and a fire was
 reported in a non-safety-related electrical system. The plant was stabilised and plant employees formed an
 event response team. About three and a half hours later, another fire was reported in a different non-safety-
 related electrical system. The second fire affected the operation of some safety-related systems and led to
  the Alert declaration at about 23:00. The NRC said no one was injured and the plant remained safely shut
On March Alert was ended about two and a half hours after it was bus-tie breaker to open began yesterday
down. The 28, 2010, an electrical fault propagated by the failure of adeclared. The inspection resulted in a fire,
     and caused lowering voltage on 1 of 3 reactor coolant pumps (RCP), initiating a reactor trip. Due to the
   failure of the breaker to open to isolate the fault, power was lost to two buses. The subsequent cooldown
  resulted in an automatic safety injection initiation on low pressurizer pressure as operators focused on the
 fire. In following the procedure to restore the plant, operators attempted to reset the main generator lockout
     relay, which resulted in re-closing a separate breaker that had eventually opened to isolate the fault, re-
      energizing the fault and causing a second fire event in the switchgear. This resulted in grounds on the
station's 2 DC buses. Further complications included a failure of the charging pump to swap suction sources
       from the Volume Control Tank to the Refueling Water Storage Tank on low level, and the closure of a           1971
 On March 28, 2010, the NRC was notified of a lube oil fire on one of the three reactor feedwater pumps. The plant’s
    fire brigade and offsite fire departments responded to the fire. The turbine-driven feedwater pump was manually
  tripped to allow the removal of the turbine lube oil system from service. The motor-driven pump, which serves as a
   backup for two turbine-driven feedwater pumps, started as designed and the reactor recirculation system lowered
  reactor power as is expected in the given conditions. The fire, which started at 6:18 p.m., was reported to be out at
       9:22 p.m. Two fire brigade members were transported to a local hospital due to signs of heat exhaustion and
  released later that night. They were verified to be free of contamination. The licensee reported no other issues with
   plant personnel or offsite fire department personnel. The licensee is in the process of identifying the cause of the
  leak, the extent of damage, and make repairs. The plant is currently at 85 percent power. NRC resident inspectors
  UPDATE: On March 30, the licensee completed inspection of the affected components and identified two potential
lube oil leak sources and made the necessary repairs. The turbine-driven reactor feedwater pump has been returned
    to service. The plant is in the process of returning to full power. The feedwater pump turbine is operating with no
    anomalies. The licensee continues to monitor for unusual conditions during power ascension. The NRC resident
 inspectors continue to monitor licensee activities on site. The information presented herein has been discussed with
  the licensee, and is current as of March 31, 2010, at 8:00 a.m. This preliminary notification is issued for information
                                       only. No further updates of the PN are planned.

  At 4:27 p.m. EDT on March 25, 2010, the plant automatically shut down in response to a main generator trip due to
  an electrical problem in a generator circuit. The problem caused the main generator and main turbine to trip, which
 resulted in an automatic scram of the reactor, as designed. All safety systems functioned as expected. The licensee
 repaired the circuit and restarted the plant at 11:05 p.m. EDT on March 27, 2010. A problem with air leaking into the
  main turbine condenser, which takes steam and turns it back into water to cool the reactor, was encountered when
     the plant was at approximately 5 percent power, and has to be fixed before the plant can go up in power. The
licensee is investigating the in-leakage and will make necessary repairs. The resident inspectors and a region-based
 inspector toured portions of the plant following the shutdown and identified no major issues. The resident inspectors
 UPDATE: The licensee identified the source of the in-leakage and made the necessary repairs. On March 30, 2010,
 the licensee was able to increase steam to the main turbine and synchronize to the grid. The plant is currently in the
  process of returning to full power operation. The resident inspectors monitored the plant restart and are monitoring
 the plant return to full power. The information presented herein has been discussed with the licensee, and is current
  as of 01:30 p.m. EDT on March 31, 2010. This preliminary notification is issued for information only and no further
                                             action by the staff is anticipated.
 INES
        REMARKS, NOTES
SCALE
2
                                   SOURCE OF INFORMATION




   PNO-III-10-001, http://www.nrc.gov/reading-rm/doc-collections/event-status/prelim-notice/2010/




    PNO-II-10-001, http://www.nrc.gov/reading-rm/doc-collections/event-status/prelim-notice/2010/




 PNO-I-10-001, http://www.nrc.gov/reading-rm/doc-collections/event-status/prelim-notice/2010/




PNO-I-10-001A, http://www.nrc.gov/reading-rm/doc-collections/event-status/prelim-notice/2010/




PNO-III-10-003, http://www.nrc.gov/reading-rm/doc-collections/event-status/prelim-notice/2010/




PNO-III-10-003A, http://www.nrc.gov/reading-rm/doc-collections/event-status/prelim-notice/2010/
  http://track.world-nuclear-news.org/y.z?l=http%3A%2F%2Fwww.world-nuclear-news.org%2FRS-
     NRC_team_to_inspect_cracks_at_Davis-Besse-1803107.html&e=14880&j=245327392&t=h




                     EMAIL NucNet News in Brief / No. 52 / 18 March 2010




PNO-II-10-002, http://www.nrc.gov/reading-rm/doc-collections/event-status/prelim-notice/2010/




                     EMAIL NucNet News in Brief / No. 62 / 31 March 2010




                      http://www-news.iaea.org/news/topics/default.asp




  PNO-III-10-005, http://www.nrc.gov/reading-rm/doc-collections/event-status/prelim-notice/2010/
PNO-III-10-005A, http://www.nrc.gov/reading-rm/doc-collections/event-status/prelim-notice/2010/




PNO-III-10-004, http://www.nrc.gov/reading-rm/doc-collections/event-status/prelim-notice/2010/




PNO-III-10-004A, http://www.nrc.gov/reading-rm/doc-collections/event-status/prelim-notice/2010/

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:1
posted:10/25/2011
language:English
pages:438
xiaohuicaicai xiaohuicaicai
About