ML11363A189

Boiling Water Reactor - Results of Root Cause Analysis Performed for Non-Compliance with ODCM Requirement

ML11363A189
Person / Time
Site:	La Crosse File:Dairyland Power Cooperative icon.png
Issue date:	12/15/2011
From:	Crainte C Dairyland Power Cooperative
To:	Document Control Desk, NRC/FSME/DWMEP
References
LAC-14205
Download: ML11363A189 (15)

Text

LA CROSSE BOILING WATER

.'REACTOR (LACBWR)

DAIRYLAND POWER COOPERATIVE December 15, 2011 In reply, please refer to LAC-14205 DOCKET NO. 50-409 Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

SUBJECT:

Dairyland Power Cooperative (DPC)

La Crosse Boiling Water Reactor (LACBWR)

Possession-Only License No. DPR-45 Results of Root Cause Analysis Performed for Non-Compliance with ODCM Requirement

REFERENCE:

(1) LACBWR Offsite Dose Calculation Manual, Rev. 11, December 2008 and reviewed with no changes December 2010 (2) Letter LAC-14191, DPC to NRC, "Non-Compliance with Offsite Dose Calculation Manual (ODCM) Requirement," October 7, 2011 (3) Root Cause Analysis Report--CAR 2011-137, December 14, 2011 On September 9, 2011, DPC determined that the plant's ventilation configuration was not in compliance with LACBWR ODCM Section 3.3.1 which requires particulate filtration of Reactor Building exhaust air.

DPC reported the condition to the NRC in accordance with the same ODCM requirement by letter of Reference 2.

DPC directed that a root cause analysis be prepared independently by Sargent & Lundy, LLC. This analysis is contained in the report of Reference 3 and is included as an attachment to this letter.

Please contact Michael Brasel of my staff at 608-689-2331, if you have any questions or comments.

Sincerely, Charles Sans Crainte, Vice President, Generation CVS:MAB:jkl A Touchstone Energy* Cooperative La Crosse Boiling Water Reactor (LACBWR)

• S4601 State Highway 35

• Genoa, WI 54632-8846

• 608-689-2331 e 608-689-4200 fax

Document Control Desk

- LAC-14205 Page 2 December 14, 2011 cc w/

Attachment:

John Hickman Project Manager U.S. Nuclear Regulatory Commission Mark Satorius .

Regional Administrator, Region III U.S. Nuclear Regulatory Commission Paul Schmidt Manager, Radiation Protection Section State:of.Wisconsin

j. ' * " '" r.

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Dairyland Power Cooperative December 14,2011 LACBWR Reactor Building Ventilation RCA Page I of 13

!t~~o~ Ca.~se A~aI~sls ftenot - CAR Np1 2011-137 1.0 Pum.=

At the direcion of the Dairyland Power Cooperative (DPC) LACBWR Plant Manager, a formal root cause analysis (RCA) was initiated to detepmine the actions and events that resulted in Reactor Building (RB) exhaust air not being filtered prior to discharge.

This independent internal investigation was conducted by qualified root cause analysis specialist, Donald Felz, with Technical Support provided by John Rich and Jeff McRill.

This report details the results of the analysis, including a description of the issue, 4*elneates #0 event timein, addresses relevant r%41 tqr4nd program information, reportson review of past CARs, identifies the extent obfkondktoi6, identifies root causes, and provides reommndations to preclude repetition of this error. The results of this analysis have been discussed with the appropriate management peemonnel.

2.0 -=07--jMT: n 51MA 175 On September 9, 2011, an error was identified that the air in the RB was not being filtered ipdor to discharge to reduce the amount of radioactive particulates being released to the environment, as reuired by Section 3.3.1 of the Offeite Dose Calculation Manual.

kil -mm - W.i An Event Timefine for this ircident is as follows:

1. Operator Log Vol. 87 indicated that the mainf rokx doors 11/30/95 were unlocked and opened.

2. -1995 Shift Supervisor Log indicated that the main aidock 11/30/95 door interlocks were overridden and both doors were open.

3. Ucense Amendment No. 69 relocated Technical Specification (TS) 4/5.2.4, Ventilation System Exhaust, 4/11/97 without change, to the Ofsfte Dose Calculation Manual by following the guidance of Generic Letter 89-01.. .... __-.

4. LACBWR Operating Manual Change No. 1498 stated, "Since we no longer leave either of the RB airlock doors shut, we should ensure a positive airflow through the RB to the stack if the RB isolates'.

5. LACBWR Operating Manual ChangeNo. 1502 was initiated to remove reference to RB integrity, test of RB integrity and 9/18/97 requirements of RB integrity.

6. LACBWR Operating Manual Change No. 1498 was

__approved.

1212/97

//9

7. LACBWR Operating Manual Change No. 1502 was 12/30/97 approved.

8. D-Plan was revised to describe the current condition that the 12.06M03

__ RB ventilation exhaust fan was not continuously in RCA - CAR No. 2011-137.doc

Dairyland Power Cooperative December 14,2011 LACBWR Reactor Building Ventilation RCA Page 2 of 13 operation. If main aidock doors were open whilethe .

exhaust fan was not in operation, unfiltered RB air would be drawn through the open main airlock doors by action of the stack blowers and discharged from the stack. (Ref. Letter LAC-13823, dtated 12116103) 9 CAR No. 2011-137 was initiated to !dn tl the ODOM

__ requirement for filtered RB exhaust was not being followyed.' _/9/1 Th6, foIllowingdocuments were rviWeod:

License No. OPR-45, Appendix A, Technical Specifications

-Li.cense.o.PR-45,......

-Decommslsioni* Plan . , ,.,

Opergling Manual R- Ventilation Operating Procod.e Operat Manual Change  : ..

- Offite Dose CalcuWlon Manual (ODCM)

. Operator Logs

- Shift Supervisor Logs Corective Action Reports (CAlb)

Si-acility Cho" -(FCs)for major RI openings'

- Maintenance Re.uens (MR) -

-Operations Review ComMitteb (ORC) Meeting Minutes

- Annual Effluent Repofts

- Generic Letter 89-01 4.1. L Mense No. DPR-45. AM&endix A.6Techical Speifications (TSb A review of the current License Amendment No.,71 TS revealed that there are no requirements noted relative to RB ventilation system exhaust. The technical requirements for RA ventilatbon system exhaust were relocated from the TS to the ODCM via Lcense Amendment No. 89.

Prior to License Amendment No. 69, TS Section 4.2.4, "RB Ventilation System Exhaust,"

required that whenever the RB Ventilation outlet dampers are open, the RB exhaust shall be through particulate filters.

4.2. L No-,

Interview with the LAC1WR Ucensing epresentative and review of relative DPR-46 Ucense Amendment records revealed the following:

RCA - CAR No. 2011-137.doc

Dairyland Power Cooperative December 14,2011 LACBWR Reactor Building Ventilation RCA Page 3 of 13 License Amendment No. 6§ d&ted July 31. 1991 This amendment for issuing LACBWR's decommissioning order and approving the Decommissioning Plan, did not provide a mechanism to make changes to the facility, such as dismantlement of unused systems, without prior NRC approval. For this reason, DPC requested a revision to the decommissioning order. The NRC issued "Confirmatory Order Modifying NRC Order Authorizing Decommissioning of Facility,"

dated September 15, 1994, permitting DPC to make changes to the facility as described Inthe Decommissioning Plan Ifthe changes did not involve an unreviewed safety question meeting three criteria that were later ontained4n the ACP-06.3 Form 2.

Under the ConfirmAory Order, dismantlement of LACOWR system accelerated. During this period the practice of opening RB main airlock doors to facilitaftdismantlement activities and the removal of large equipment began., This time frame Is verfied with the Shift Supervisor and Operatqr Log entries of November 30, 1995, referenced in Sections 4.8 and 4.9 of this report.

The final rule, =Decommissloning of Nuclear Power Reactors,0 was published in the Federal Register July 1998 (61 FR 39278, July 29, 1996). In the rule, the NRC established that licensees would be allowed to perform decommissioning activiltis that meet the criteria of 10 CFRP 50.59, as amended, to ensure that concerns specific to decommissioning were considered by the licensee.

LWentse Amedm~en t- fig0 aroEM Andlif 1997R This amendment revle license condition 2- to establish 50.59 as applica to LACBWR. Importantly, this amendment also removed cpntainment integrity requirements. In the Safety Evaluation Report (SER) discussing the deletion of TS dealing with leak testing and maintenance of containment integrity, the NRC stated:

'The worst fuel pool accidentthat could occur is the loss of all gap activity from the 333 spent fuel assembliesstoredin the pool. As noted in the evaluationof the old Subsections 4/5.1 FUEL STORAGE AND HANDUNG. above, the consequences of this accident were previously found acceptableby the staff. In that analysisit was assumed that the containment was not functional; therefore, the continuedmaintenance of the integrityof the containmentto resist LOCA forces or the loss of all spent fuel gap activity is not required."

As documented in the Safety Analysis for Operating Manual Change No. 1502, initiated September 18, 1997, LACBWR staff interpreted the deletion of containment Integrity requirements as meaning the function of the RB to mitigate the consequences of any credible accident at LACBWR was no longer necessary. Since there was no longer a required containment function and airborne particulate levels were insignificant to the public health and safety even under worst case accident conditions, the direction shifted to maintaining monitoring capability of the exhaust from the facility at the stack release point. This direction is evident in evaluations of changes from this time forward where it is repeatedly documented that changes did not adversely affect the monitoring pathway or that the monitored path was maintained. This monitoring focus was in keeping with 10 CFR 50, Appendix A, Criterion 64 which states:

RCA - CAR No. 2011-137.doc

Dalryland Power Cooperative December 14,2011 LACBWR Reactor Suilding Ventilation RCA Page 4 of 13 "Monitorin radioactLvfty rlases. Means shallbe provided for monitoringthe reactorcontainment atmosphere,spaces containingcomponents for recirculation of loss-o-coolant accidentfluids, effluent dischargepaths,and the plantenvirons for radioactviy that may be releasedfrom normaloperations,including anticipatedoperationaloccurrences,and from postulatedaccidents."

The NRC approved License Amendment No. 69 to relocate the requirements for RB Ventilation System exhaust from the TS, without change, to the ODCM by following the guidance of NRC Generic Letter 89-01. The basis of the NRC approval was that the ODCM is referenced in the Defueled Technical Specifications (DTS) Subsection 8.4.2.2, which requires the licensee to maintain the ODCM and provides the mechanism for changes to the ODCM. TS Sectiof 4.2.4 that was moved to the ODCM stated that whenever the RB Ventilatioh outlet dampers am open, theiRB Ventilation System exhaust shall be through particulate filters. It should be noted that the ODCM had already been revised to incorporate TS Section 4.2.4 in ODCMRevision 4, dated March 1998. ..

4.3. F!77-71717771"T' Section 5.2.29 of the D~Plan that was in place (Revision - October 1998) at the time License Amwendmnt No. 69 was approved stated:

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'fThe:ReatorBuilding ventilation system utilizes'two 30-,on, 12,000Wdfm air conditioning units for drawingfresh airinto the building and for circulatingthe'air.

throughout the building. The airenters the ReactorBuilding through two 20-inch Isolationdampers in series, and is exhaustedfrom the building by a centrifugal exhaust fan which has a capacity of 6000 cfm at 4 inches of water static pressure. The exhaust fan dischargesthrough two 20-inch isolation dampers in

-%seriestothetunnel..... . r"..,

A 20nch damperis also providedfor recirculationof the exhaust fan discharge air. The exhaust system is provided with conventionalandhigh-efficiency filters and with a gaseousand particulateradiationmonitor system.

Under the above configurton the air could not be exhausted through the stack unfiltered.

Section 52.29 of the current "-Plan (Revision - November 2010) states:

"The ReactorBuilding ventilation system utilizes two 30-ton, 12,000-cfm air conditioningunits for drawingfresh airinto the buiding and for circulatingthe air throughoutthe building. Each air-conditioningunit airinlet is provided with a filter box assembly, face andbypass dampers, and one 337,500-Btwuhrcapacity steam coil that are used when heating is required Air enters the building through two series 20-inch dampers and is exhaustedfrom the buildingby action of the stack blowers Additional exhaust flow is availableusing a centrifugalexhaust fan that has a capacityof 6000 cfn at 4 inches of waterstaticpressure. The exhaustfan and buildingexhaust airdischargethrough two series 20-inch dampersto the Reactor Building ventilation outlet plenum connected to the tunnel.

RCA - CAR No. 2011-137.doc

Dairyland Power Cooperative December 14,2011 LACBWR Reactor Building Ventilation RCA Page 5 of 13 A 20-inch damperis also provided for recirculationof the exhaust fan discharge air. The exhaust system is provided with conventional and high-efficiency filters and with a gaseous and particulateradiationmonitorsystem."

Under this configuration the air could be exhausted through the HEPA filters in the RB to the stack or unfiltered through open main airlock doors through the turbine building to the stack f the exhaust fan was not running. The above change was made to the D-Plan as part of the annual D-Plan update to the NRC (Letter LAC-1 3823, dated 12/16/03) that, as stated in the submittal, was made to bet describe current conditions (i.e., exhaust fan not in continuous operation) but did not include discussion of the open main airlock doors configuration. The 50.59 screen for the 2003 D-Plan Annual Revision did indicate review of ODCM Sections 3.3.4 and 3.5, but did not indicate review of ODCM Section 3.3.1, which required filtration from the RB prior to discharge.

Additionally, the 50.59 procedure that was in effect when the review was pedormed (ACP-06.4, Issue 1, dated 4/21/03) did not specifically require the ODCM to be reviewed. It should be noted that the requirement to review the ODCM was added to ACP-06.4 in lssue 4 (dated6112/08). *. -

1. The 50.59 screen for the 2003 D-Plan Annual.Revisiondid, not review oDCM Section 3.3.1, which required ftration from theRa prior to dischlrge. The 50.59 procedure.

that was in effect when the review was perfrmed (ACP-C6.4, Issue 1, dated 4/21/03) did not specifically require the ODCM to be reviewed.

2. The current revised 0-lan does not describe the main airock doors open configuration and the effects that configuration has on air efflnt from the RB being filtered prior to discharge out the stack.&. - .

S ,-

4.4.

LACBWR Operating Manual, Volume-V, Service System (Revision - February 2011),

Section 10, "Heating, Ventilation, and-Air Conditioning Systems," does not address the current main airlock doors open configuration.

Issu~es):

1. The LAC8WR Operating Manual, Volume V, Section 10 was not revised to reflect the current conditions (i.e., RB main airlock doors might be open).

4.5. RB Ventilation OoeQRtlina Procedure Procedure OP-87-02, "Operation of RB Bi-Parting Doos," was reviewed. The purpose of this procedure Is to provide instructions for operation of the RB bi-parting doors. The procedure addresses the need to establish conditions for adequate airflow into the RB from outside to prevent unmonitored release of air effluent- It does not address the requirements for filtration of air. Steps 3.1.1 through 3.1.8 establish the actions required to establish a path for airflow from the RB to the stack. Specifically, step 3.1.6 states RCA - CAR No. 2011-137.doc

Dairyland Power Cooperative December 14,2011 LACBWR Reactor Building Ventilation RCA Page 6 of 13 that both main airlock doors are to be open. The procedure does not identify the steps for returning the RB back to its normal condition.

A review of the 50.69 screen performed for Procedure OP-87-02 revealed that it did not address the need for the air to be filtered prior to discharge to the stack.

1. The 50.69 screen for Procedure OP-87-02 failed to recognize that the air effluent from the RB was required to be filtered prior to discharge out the stack.

2. Procedute OP-87-02 does not identify the steps for returning the RB ventilation back to its normal condition.

4.6. Operating ManuaI Chanes, On July. 15, 1997, LACBWR Operating Manual Change No. 1498 was initiated. This change stated that since LACBWR does not leave either of the RB airlock doors shut, there isa need to ensure a posltive aklow through the RB to the stack if the RB isolates.

The "Reason for Changes! section of the ACP-06.3 Form 2 acknowledges that the RB airlock door are no longer kept shut. This change was processed in accordance with ACP-06.3, LACBWR Operating Manual Review (Rev. 16, dated 8/16/95), which required that a Safety Analysis in Accordance with Decommissioning Plan and Technical Specfications (ACP-06.3 Form 2) be performed. This change was approved on December 2, 1997 and incorporated into the LACBWR Operating Manual, Volume I, Integrated Plant Operations, Alarm C81, "Reactor Building Dampers Closed."

On September 18, 1997, LACBWR Operating Manual Change No. 1502 was initiated.

This change *as Initiated to remove reference to RB integrity, test of RB integrity and requirements of RB integrity. The stated need for the.change was that the Containment Buildingr Integrity was removed from the TS under License Amendment No. 69. Included in the change was acknowledgement that the airlock doors mechanical interlock is normally disabled to allow both doors to remain open. This change was processed In accordance with ACP-06.3, LACBWR Operating Manual Review (Rev. 16, dated 8/16/95), which required that a Safety Analysis in Accordance with Decommissioning Plan and Technical Specifications (ACP-06.3 Form 2) be performed. This change was approved on December 30, 1997, and Incorporated into the LACBWR Operating Manual, Volume XI, Reactor Containment Building. "

As previously noted In Section 4.2 of this report, the NRC approved License Amendment No. 69 on April 11, 1997, to relocate the requirements for RB ventilation system exhaust from the TS, without change, to the ODCM. Therefore, the Safety Analyses that were performed for Operating Manual Changes No. 1498 and 1502 would not have noted the requirement for RB exhaust to be filtered prior to discharge out the stack. Additionally, ACP-06.3 did not specifically require that the ODCM be reviewed, and the Safety Analyses failed to recognize that the D-Plan required RB exhaust being filtered prior discharge out the stack.

RCA - CAR No. 2011-137.doc

Dairyland Power Cooperative December 14,2011 LACBWR Reactor Building Ventilation RCA Page 7 of 13 1.. The Safety Analysis in Accordance with Decommissioning Plan and Technical Specifications (ACP-06.3 Form 2) performed for LACBWR Operating Manual Changes No. 1498 and 1502 did not recognize th that the ODCM required the RB exhaust air to be fiotered prior discharge out the stack.

4.7. Osite Dt uai (0M The OCM (Rev. 11, dated December 2010), Section 3.3.1, "Gaseous Effluents -

Reactor Building Isolation," states:

"Normalairdischargefrom LACBWR is made as an elevated stack release. Air is swept throughthe Turbine Building andRB and then Oshargedup,the stack.

Wenever the RB Venttn Oaompe am oen, the airfrm l* shallbe R4 dischargedthrough a set ofHEPA patkcate fler to.reluceUe amountof.,

,,.ad/activepafticee being releasedto *4e0e4v'onrent:.This f. *.nof the RB Ventilation Sydst&- exhautlmp4 mntts,b erquhernents of 10 CFR Part 50.36a, General.DesIn.C9tarlo,.0of Appendix A to 10CPR Part 50,; nd the, design objectives in $acton l.D 9of.Appenxifbto 10 CFR Part50.. *,,

With RB Ventilation System: exhaust being dischrgedwithout filtation,prepare and submit to the Commissiqn.within.30days a.,SpecialReport which dWspus the circumstancesand **at action Will be taken to prevent recuqunce.

During normal SAFSTOR operations, radioactive airborne particulate cncentrations in the RB range from IOE-11 to IOE-12 pc/cma and are insignificant. Postulated accident conditions do not create radioactive airborne particulate having any significance to the public health and safety. Despite these fat., the ODCM Section 3.3.1 requirement for filtration of air from the RO to reduce the amount of radioactive particutates being, released to the environment hos no been changed.

I. LACBWR did not recognize that they were not in compliance with this ODCM requirement to discharge air through the HEPA filters when the RB ventilation dampers were open while the exhaust fan was not running with main airock doors open.

4.8. Omma Lows Operator logs were reviewed to determine when the RB main airlock doom were opened for extended periods, over and above normal opening for equipment removal, etc. This review noted the following:

RCA - CAR No. 2011-137.doc

Dairyland Power Cooperative December 14,2011 LACBWR Reactor Building Ventilation RCA Page 8 of 13

- Operator Log Vol. 87 indicated that the main airlock doors were unlocked and opened on 11/30/95.

- Operator Log Vol. 89 indicated that the main ailock doors were closed on 10/13197.

- Operator Log Vol. 89 Indicated that the RB door is shut and then opened on 3/15/98.

4.9. Shift Suesor LoMs Shift Supervisor Logs were reviewed to determine when the RB main airlock doors were opened for extended periods, over and above normal opening for equipment removal, etc. 1995 Shift Supervisor Logs documented that the main aidock door interlocks were overridden and both doors were opened n t1130/95.

4.10. Corective Action Reports (CARs) . .

A database search for CARs related to RB ventilation was performed. CAR No. 2009-17, initiated on 3/4/09, noted that as a result of the access door (bi-parting doors) being installed, the RB was no longer airtight and that procedures for Hi-Red Alarms were not changed to ensure negative pressure would be maintained in the RB and that there would be no chance for an unmonitored discharge from the building. Operating Manual changes weiproposed and an immediate temporary charnge Was initiated. The causal analysis performed indicated that the there was no analysis performed of what the affect of the b-parting door installation (Ref. Facility Change FC-37-06-34) may have on the overall RB ventilation system. It stated that the initial analysis (for FC-37-06-34) of this situation was not sufficient, but was being addressed, and that a review of the ODCM indicated that even though and monitored air effluents are required, a loss of either filtration or monitoring can be dealt with In a planned recovery evolution.

1. Although the causal analysis recognized that the ODCM required air effluents to be filtered, it did not result in any actions to bring the RB Into compliance with the ODCM filtration requirement, or recommend that the ODCM be changed to reflect actual operating conditions.

4.111. EFaclty M (F-C-*1for mHiofRBog incw The following 50.59 Evaluations were reviewed for the Installation of the Reactor Building Bi-Parting Doors:

FG-37-06-3. Reactor Buildina Modification. dated 10123/06 RB air inflow was addressed to maintain a monitored gaseous effluent path to the stack by employing a combination of strategies available. Among the options noted were; operating the 6,000-cfm RB exhaust fan, and operating the two 35,000-cfm stack blowers. Filtration requirements from the ODCM were not addressed.

RCA - CAR No. 2011-137.doc

Dairyland Power Cooperative December 14,2011 LACBWR Reactor Building Ventilation RCA Page 9 of 13 FC-37-06-34. Reactor =uidinaRestorationActivities, dated 11/5/06 RB air inflow was addressed to maintain a monitored gaseous effluent path to the stack by employing a combination of strategies available. Among the options noted were; operating the 6,000-cfm RB exhaust fan, and operating the two 35,000-cfm stack blowers. Filtration requirements from the ODCM were not

• addressed.

MOSu~ ): *. .:,  ::

1. When the 50.69 evaluations for the above FCs were performed,: the D-Plan had not been revised to allow for unfiltered exhaust discharge out-the stack, the filtration requirements were already moved from the TS to the OXCM, andthe 50.59 evaluation process did not specifically requirfthat tIhe ODCM be rev*#md.

Consequently, thereiere no pocbse baftiers that would have alentified the requirement for RB airfiltration td#rto discharge.

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4.12. 1247,1717=LM-7. 0-777,77-Tilt]

Ameview of MRs associated with RB door maintenance did not reveal any activities pertinent to the timeline for when the main airlock doors were opened and dosed for extended periods.

4.13. ORC f Min The following ORC meeting minutes were reviewed:

Jnuy 211997- Discussed a memo from the Mechanical Maintenance 7." 0pettiO#ftt permission to defer the 3-year preventive maintenance (PM) on the Personnel Aidock inner door. The airlock was stated to be in a failed"mods and the ba vave Is not ued.

Failed mode would imply that the mecharnc interlocks between the Inner and outer doors were dafeatediremoved to allow independent door operation, or both doom open.

1. 1 I Discussed f the Reactor Bin Isolates'automatically, then Operations will atmtn to restore Reactor Building air flow. If it is not possible, on-airlock door will need to be closed to ensure positive air flow from the Reactor Building thrugh the stack This would Imply that the air lock doors were normally in the open position.

4.14. Annua Efflent Reno..s The Annual Radioactive Effluent Reports for 1990-2010 were reviewed. Although the annual doses to the public were well below 10 CFR 20 and 40 CFR 190 limits during the period from 1990 through 2010, the gaseous effluent release data for this period was RCA - CAR No. 2011-137.doc

Dairyland Power Cooperative December 14,2011 LACBWR Reactor Building Ventilation RCA Page 10 of 13 reviewed to determine if bypassing the filtration units had a measurable effect on dloses to the public. The release data indicate that the effect of operating without filtration is insignificant. In part, this is because the dose rates from 1995 through 2010 are less than the liowest dose rate between 1990 and 1995, which also means that bypassing the filtration units did not increase the annual dose above that which is already well below regulatory limits.

The maximum annual organ doses for the perod from 1990 through 2010 are plotted in Attachment A to this report. The doses during the perod from 1995 through 2010 (bypassed filtration) are less than a few percent of the doses from 1990 to 1995 (with filtration). For the purposes of estimating the maximum dose reduction that could be achieved by filtration, it is assunedthat the fle are 99% efficient (which'is conservative for estimating the maximum effect the filters could have on doses). With this assumption, the largest possible dose reduction would be 99% of the maximum dose during the period from 1995 through 2010, which is 1.58E-04 mRem. Thus the maximum dose that could be eliminated by the fiftersie less than 1.58E-4 mRem. This is an insignificant fraction of the dose limits of 10 CFRz20(100 mRemr TEDE), 40 CFR 190 (25mReom organ dose) or 10 CFR 50 Appendix 1(15 mRem organ dose). Therefore it is concluded that operating without filtration had an insignificant effect on compliance With btaU dob.imits to the public.

4.15. Generic2Letr89-01 -..

Generic Letter 89-01 addresses the "Implementation of Programmatic Controls for Radiological Effluent Technical Specifications (RETS) in the Administrative Controls Section~of the-Technical Specifications andthe Relocation-of Procedural Details of RETS to the OffIite Dose Calculation Manual or to the Process Control Program. It was verified that the guidance of this GL was followed when TS Section 4.2.4 was incorporated into the ODCM under UWendeAmendment No: 69.

The extent of this condition with regards to moving TS requirements to other controlled mechanisms, such as the-OCOM Is negligible. There have been no subsequent license amendments that resulted in moving TS requirements to lower tier implementing documents.

The extent of condition with regards to the adequacy of 50.59 reviews is indeterminate.

The 50.59 screens and evaluations reviewed were specific to activities surrounding RB ventilation, and it was determined that they were not performed adequately. However, an extended review should be performed on other non-RB ventilation related Safety Analyses and 50.59 reviews conducted during the period in question to determine overall adequacy of the Safety Analysis/50.59 review process.

6&0 R&OT UiME CONQLU81ON The annual doses to the public were well below 10 CFR 20 and 40 CFR 190 limits during the period from 1990 through 2010. The gaseous effluent release data for this period revealed that bypassing the filtration units did not have a measurable effect on RCA - CAR No. 2011-137,doc

Dairyland Power Cooperative December 14, 2011 LACBWR Reactor Building Ventilation RCA Page 11 of 13 doses to the public. The release data indicates that the effect of operating without filtration was insignificant.

A human error and organizational/programmatic diagnostic flow chart were utilized to determine the organizational/programmatic and human error root causes that exist. The primary purpose for utilizing this technique is to identify the apparent causes and to assure that the investigative technique was thorough and complete to aspure that the resultant recommendations are consistentwM. regards to adequay addressing the issues.

Thehuman error rto u was Inadequate 50.59 Training (i.e. nWtrlning for the needed skills or'" n not compete or dtoiled enough). Posslblcontributing factors include inadequate managerial methods.

The Organizational/progammAMOotcause was Insufficient DetaiL (Le. vagueness in procedures).' Possible 66ftiritiflgtdt W de inadequate proram design and inadequate work planning process. It should be noted that the requirement to review the ODCM was added to ACP-06.4 in Issue 4 (dated 6112/08).

7.0 REgg.QFND~ADtfi After reviewing the pertinent information and considering the identified root causes, the

.-f.olkwrng ecommendations are provided:

1. Revise the ODCM and OfW, as needed, to provide relief from the.filtration requirement and to reflect the appropriate operating configuration.

2. Evaluate Safety Analyses and/or 50.59 reviews conducted on other Important-to-Safety (ITS) and Quality Level I Non-RB Ventilation systems conducted since License Amendment No. 69 was issued to assess the adequacy and effectiveness of the 50.59 reviews.

3. Conduct training for personnel qualified to perform 50.59 reviews to reinforce the requirements and expectations of ACP-06.4 for the 10 CFR 50.59 review process.

4. Revise LACBWR Operating Manual, Volume V, Section 10, "Heating, Ventilation, and Air Conditioning Systems," as required, to reflect the current operational configuration of main airlock doors open.

5. Revise procedure OP-87-02 to Identify the steps for returning the RB back to its normal operating condition.

RCA - CAR No. 2011-137.doc

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