bruce power

8/14/2019 Bruce Power

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CMD 10-M13

Date: 2010-01-26

File / dossier : 6.02.04

Edocs 3490675

Early Notification Reports Rapports de notification rapide

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Bruce Power:Alpha Contamination Event in Bruce A

Unit 1

Bruce Power: Bruce A Unit 4Unanticipated SDS2 Trip

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Bruce Power :Contamination alpha la tranche 1 de

Bruce-A

Bruce Power : Dclenchement imprvu duSAU2 de la tranche 4 de Bruce-A

Commission Meeting Runion de la Commission

February 18, 2010 Le 18 fvrier 2010


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4.1.1 Bruce Power:

Alpha Contamination Event in

Bruce A Unit 1

10-M13 4.1.1 Bruce Power :

Contamination alpha la tranche 1

de Bruce-A


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e-docs #3489957

Prepared by DPRR / Bruce Regulatory Program DivisionUcenseeBruce PowerWhen event/situation was discoveredDate: 2010-01-05

Location Tiverton, OntarioHave Reporting Requirements been met?YES

OVERVIEWDescription: On November 26th, 2009, workers at Bruce A Unit 1 conducting a routine airbornesurvey in the vault found the presence of long-lived particulates. Radiation controls were re-inforcedand sample frequency was increased. Follow-up analysis identified the particulate to be Cobalt-60 andalso the presence of alpha contamination. The alpha contamination was quantified by a third party onDecember 21, 2009. Preliminary dose calculations were completed January 5, 2010 and wereconservatively interpreted as a potential indication that an action level for inhalation of airborneradioactivity may have been exceeded. Up to 217 workers may have been affected by this event.C8use(s): Activated corrosion products in the feeders in Bruce A Unit 1 became dislodged duringfeeder grinding activities.

REASON FOR NOnFlCAnONCriterion 10 from CMD 03-M68 "An occurrence or incident that receiVes, or may receive, substantialmedia coverage or that has a high public visibility".

EFFECIS OF THE EVENT/SUUAnON - ON

Persons

EnvironmentSecurityOtherimplications

Who affected:Workers: potential for exceeding an action level; regulatory limits are not likely tohave been exceededPublic: noneHow affected:NoneNot applicableNone


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e-docs #3489957UCENSEE ACTIONS

Taken or in progress: An oral notification was provided to CNSC staff on January 5, 2010 once itwas determined that an action level may be exceeded, which is a licence reporting requirement. APreliminary Report was submitted to the CNSC on January 7, 2010.Work in the Unit 1 vault was stopped until clean-up of the alpha contamination was complete. Workerspotentially affected by the incident have been removed from other radioactive work until additionalinformation regarding the exposures is obtained.Analysis is currently underway at Chalk River Laboratories to determine the actual doses received bythe workers. This should be complete by the first week of February. In the meantime, Bruce Powerhas placed alpha-sensitive monitors at strategic locations in Units 1 and 2 in order to identify anyfurther potential contamination.Planned: Bruce Power will continue to update CNSC staff with new information as its obtained andwill submit a Detailed Report as per regulatory reporting requirements.An additional alpha-sensitive monitor has been ordered for the West End Complex as an additionalbarrier for monitoring.

CNSC ACTIONSTaken or in progress: CNSC staff has been monitoring the situation, ensuring that the licensee isaware of the extent of condition of cause of the event and that they are taking the appropriatecorrective actions.Planned: CNSC staff will continue to monitor the situation, including the conduct of enhancedinspection activities as well as review of the Detailed Report when submitted.Further reporting: No

NAMEDirectorate- Bruce Regulatory programDivision - Director - Ken Lafreniere

SIGNATURE

P A , r u ~ J Director General


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4.1.2 Bruce Power:

Bruce A Unit 4 Unanticipated

SDS2 Trip

10-M13 4.1.2 Bruce Power :

Dclenchement imprvu du SAU2

de la tranche 4 de Bruce-A


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e-docs #3489726

Prepared by OPRR - BRPOUcensee - Bruce Power Inc.When event/situation was discoveredDate: 2010-01-14

E-doc # 3489726Location Bruce A, Unit 4Have Reporting Requirements been met?YES

OVERVIEWDescription (What happened?): Operating staff were performing a routine Shutdown Systemnumber two (5052) safety System Test (SST) on one r i the three channels (channel G of channel G, .Hand J).While Channel Gwas tripped for this test, Channel J tripped spuriously which caused a completed 5052trip and poison injection, which shuts down the reactor.cause(s): The event was a result of the unantidpated Ch J trip while Ch G was tripped for testing.The root cause of the Ch J trip is unknown at this time.

REASON FOR NOnFlCAnONActuation of a Shutdown System during reactor operation.Criteria B.3-1 of CMO 03-M68

EFFECTS OF THE EVENT/SITUAnON - ONPersons

EnvironmentsecurityOtherimplications

Who affected There were no persons affected by this eventHow affectedNo impactNo impactno impact

UCENSEE ACTIONS

French version - e-docs # 3449609


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e-docs #3489726

Taken or in progress:Bruce Power staff followed procedures

At the time of the event the Unit transient tone was sounded. A Power Reduction Action Guide for 5052 was completed 5051 was manually tripped as per procedure. Turbine was tripped and monitored as per procedure.

There were no human performance issues identified. Crew demonstrated very good response to thetransient. Bruce Power also determined that the operability of other units was not affected.Due to the shutdown of the unit, Bruce Power decided at this time to complete a design change thathad just been completed in Unit 3.Planned: Bruce Power is performing a root cause investigation.

CNSC ACTlONSTaken or in progress: CNSC Site Staff reviewed Bruce Power's actions after the event and verifiedthat there were no unforeseen issues that occurred as a result of the trip (i.e. the station operated asexpected on initiation of 5052 trip).Planned: Review the detailed report and root cause investigation report when they become availableto verify that the assigned Bruce Power corrective actions are appropriate.Further reporting: The detailed report which will indude the root cause will be submittedto the CNSC as per 5-99 procedures.

NAMEDirectorate - Bruce Regulatory ProgramDivision - Director - Ken Lafreniere A d , ' ~ Direetor General

SIGNATURE::kTl 0 0, 1 - f

Date

French version - e-docs # 3449609

bruce power

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