april 29th, 2011 - consortium of industrial and governmental organizations analysis of tepco roadmap...

8/13/2019 April 29th, 2011 - Consortium of Industrial and Governmental Organizations Analysis of TEPCO Roadmap at Fukus

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PMT.japan ResourceApril 29 roadmap analysis Rev7.docxApril 29 roadmap analysis Rev7.docx

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AllAttached is the final Consortium approved Roadmap analysis.Chuck NortonRST BWR Analyst

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The United States Consortium of Industrial and Governmental Organizations* analysis ofthe adequacy of the Tokyo Electric Power Company TEPCO) Roadmap for the purposeof achieving near term plant stability goals established by the Consortium

Introduction: The United States Consortium of Industrial and GovernmentalOrganizations associated with nuclear energy suggests near and longterm goals for the stabilization of the damaged Fukushima Daiichi nuclearunits. This document is not an official position of the U.S. NuclearRegulatory Commission or associated industrial or governmental entities.It is meant as technical insights to the Government of Japan on theTEPCO Roadmap. It is understood that the responsibility and decision-making regarding meeting these goals is the responsibility of TEPCO andthe Japanese regulatory body.

As requested, the purpose of this analysis is to evaluate if he TEPCORoadmap will accomplish the near term actions necessary to minimizeradiological releases and reestablish safety functions. The consortiumconsiders these functions to be reasonable to support long-term effortsthat will be needed to achieve a safe end state.

4 Purpose:

Note: The TEPCO Roadmap is included as an attachment to this document.

Background:The consortium has established five essential functions necessary for achieving the near term(TEPCO s Step 2 6 to 9 months)) goal of establishing plant conditions that provide reasonableconfidence that unanticipated conditions will not require increased Protective Action measures.These five essential functions are as follows:

1. Remove decay and chemical heat from reactors, containment, and spent fuel pools.2. Maintain reactors and spent fuel pools subcritical and adequately shielded.3. Ensure structural integrity for all units (e.g. containment and spent fuel pools).4. Provide reliable indication of essential parameters.

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Offi.ial UscOnl.y Sensitive Internal Information5. Terminate or render insignificant) uncontrolled radioactive releases.

Factors used to evaluate the status of the essential functions are as follows:

1. Remove decay and chemical heat.

a. Establish reactor pressure vessel RPV) water level, reliably maintained, abovetop of the active fuel TAF). If unable to maintain RPV water level, establish an dmaintain containment water levels covering the RPV lower head. Reduce RPVtemperatures to less than 100 degrees Celsius.

b. Provide functional and reliable backups, including power sources, for each ofthe systems being used; ensure backups can be employed in time to maintainadequate cooling.

c. Establish a functional and clean water source of sufficient capacity to ensureadequate on-site cooling water.

d. Establish the ability to reliably add makeup water to each spent fuel pool andmaintain spent fuel pool temperatures less than 100 degrees Celsius.

2. Maintain reactors and spent fuel pools sub-critical and adequately shielded.

e. Establish reliable means, either chemical or geometric, to maintain each reactorand each spent fuel pool sub-critical.

f. Establish adequate shielding or zone of protection around reactors and spent fuelpools to allow for the safe execution of Roadmap countermeasures.

3. Ensure structural integrity for all units (e.g. containment and spent fuel pools).

g. Preclude detonation in primary containment atmosphere by establishing a non-combustible atmosphere in the primary containment.

h. Establish reasonable assurance of Reactor Pressure Vessel, PrimaryContainment, and Spent Fuel Pool integrity.

4. Reliable Indication of essential parameters.

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L Establish reliable means to determine key parameters associated with actual orpotential large releases.

i. Instrumentation to confirm reactors and spent fuel pools are sub-critical,ii. Area Radiation, gaseous and liquid release detectors,iii. Reactor Pressure Vessel/Drywell/Suppression Pool RPV/DW/SP) level,

RPV/DW/SP pressure indications, RPV/DW/SP temperaturesiv. Spent fuel pool level, temperature indications

5. Terminate or render insignificant) uncontrolled radioactive releases

j. Establish the means for containment of significant external leakage (e.g. primarycontainment leakage) for portions of the plant (spent fuel pools or reactor units)with credible potential for energetic releases of significant quantities ofradioactive material.

k. With regard to activities in close proximity to the site, consider measures tominimize further spread of contamination e.g., covers or resin spray oversignificant sources of loose contamination at the plant).

Summary of US Technical Suggestions:

The following are suggestions to enhance TEPCO s ability to achieve its stated Roadmaptargets. They are suggestions that, ifenacted, could better align the Roadmap to theConsortium s stability recommendations.

The Roadmap contains the essential countermeasures for core and spent fuel cooling.Completion of these elements as quickly as possible will reduce the risk of further damages.Obstacles to flooding of the containments, e.g., radwaste processing should be given priority sothat containment flooding can begin as quickly as possible.The equipment used to add water to the spent fuel pools i.e., giraffes) are a single point offailure that could result in a loss of cooling function to the 1F1 and 1F4 spent fuel pools. TheConsortium encourages TEPCO to provide independent, redundant backup means of cooling

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Official Use,O.y - Sensitive Internal Informationthe spent fuel pools 1F1 and 1F4 that can be employed in time to provide adequate coolingshould the primary means fail.

Based on photographs of 1F1 it is not clear to the Consortium that water is actually reaching thepool. The Consortium encourages TEPCO to pursue additional investigations to validate thatthe spent fuel in spent fuel pool 1F1 is being cooled.

The consortium recommends that TEPCO consider adding a redundant means of adding wateras a backup to the normal fuel pool cooling systems for the 1F2 spent fuel pool. Restoration ofthe cooling function of fuel pool cooling system would also increase reliability.

The Consortium recommends redundant delivery systems with multiple points of injection toeach of the seven fuel locations requiring emergency cooling to improve the reliability of thecooling function. In addition, installing pipes that are seismically supported, in place of firehoses that are currently being used to carry cooling water may improve system reliability in caseof aftershocks.

The Consortium acknowledges the need to circulate water back to the RPVs to improve thewaste-water generation situation. Coupling this action with redundant delivery systems to thefuel locations requiring emergency cooling would be highly beneficial.

The TEPCO Roadmap is silent on maintaining the fuel sub-critical. Fuel movement andstructural degradation have the potential to increase reactivity. Actions to further prevent ordetect inadvertent criticality, such as adding borated water to spent fuel pools, would improveconfidence that inadvertent criticality will not inhibit recovery actions.

The fuel configuration in 1F1, 1F2, and 1F3 spent fuel pools has not been verified. Verificationof actual conditions in the spent fuel pools would help inform the proposed countermeasurescontained in the Roadmap.The Consortium encourages continued prevention of a hydrogen explosion by implementingnitrogen injection into the Primary Containment Vessels PCV) for 1F2 and 1F3.

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TEPCO Roadmap structural concerns related to spent fuel pools are primarily focused on the1F4 spent fuel pool. However, the structural integrity of reactor building 3 also appears to bedegraded from the explosions. Although 1F4 spent fuel pool may have more significantconsequences because the full core was offloaded from 1F4 reactor core, the consortium alsoencourages TEPCO to assess the structural integrity of the 1F3 spent fuel pool, and confirm thestructural integrity of spent fuel pools 1F1 and 1F2.

Instrumentation is showing signs of degradation and will continue to degrade with time.Investigation and development of alternate instrumentation systems will be necessary to ensurecritical parameters will continue to be monitored, and that the data will be accurate. Also,recovery of installed instrumentation, where possible, will be helpful.

Consideration should be given to the issues of biological growth within the reactor vessels,primary containments, and the spent fuel pools. It is likely that sea water used for emergencycooling included some life forms capable of enduring temperatures and radiation dosescurrently present much as was the case at Three Mile Island TMI). It is likely that seawater alsoprovides nutrients for such life forms. Growth of the life forms could at a minimum reducevisibility in the waters again as was the case at TMI. In a worst case, growth of life forms couldaffect coolability of the fuel either by reducing flows or reducing heat transfer coefficients fromsurfaces.

Analysis:

The analysis that follows assesses the adequacy of the TEPCO Roadmap countermeasuresand risk considerations. It addresses the factors necessary to satisfy the five Consortiumidentified essential functions necessary to provide reasonable confidence that unanticipatedconditions will not require increased protective action measures.

Understandably, the TEPCO Roadmap presents a high-level strategy with timeframe goals andis not a project plan and schedule. Itaddresses key objectives such as shifting to recirculationand heat exchanger based cooling, flooding the primary containment vessels to improve corecooling, stopping the containment water leakage that is preventing containment flood up, andradioactive waste water reprocessing. The Roadmap lays out a path that accomplishes thestated objectives. However, the practicability of achieving the step 1 and step 2 objectives in

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Official Use Only - Sensitive Internal Informationthe indicated timeframes cannot be reliably assessed considering the tremendous challengesinvolved in achieving some of the pivotal goals. For example, flooding the 1F2 core depends onhaving an intact RPV or stopping the suspected leak in the suppression pool. Considering thelack of access to the damaged area it is impossible to accurately assess the feasibility andtimeframe for such a repair. For such items, further details developed by TEPCO will enable amore meaningful assessment of the planned actions. Thus, we suggest that thecountermeasures be prioritized, further defined, and scheduled so a clearer view of siteactivities can be gained. Those priorities will guide specific action plans and specific actions asTEPCO progresses through recovery.

Note: For clarity US Consortium items will be non-italicized; TEPCOcountermeasuresand riskswill be italicized

Note: Because it may not be possible to accomplish some proposed actions in the near future,individual assessments of each reactor unit and spent fuel pool may be necessary todemonstrate that the five essential functions are accomplished without necessarily complyingwith each individual factor.

Factors used to evaluate Essential Function 1 (Remove decay and chemical heat)

a. Factor: Establish reactor pressure vessel RPV) water level, reliably maintained,above top of the active fuel TAF). Ifunable to maintain RPV water level, establishand maintain containment water levels covering the RPV lower head. Reduce RPVtemperatures to less than 100 degrees Celsius.

(Unit FI and Unit F3)

Countermeasure 9]: Flood the primarycontainmentvessel (PCV)up to the top of activefuel (TAF).

Countermeasure 10]: Reduce the amount of radioactivematerials utilizationof standbygas treatmentsystem (filter), etc.) when PCV venting (releaseof steam containingradioactivematerials nto the atmosphere).

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Countermeasure 11]: Continuepreventinghydrogen explosion by injectingnitrogen intothe PCV.

Risk [4]: Increase n waterleakage into the turbinebuilding in the process of flooding thePCV.

Countermeasure 12]: Considerationand implementationof measures to hold down waterinflow (e.g., circulatingthe water back into the RPV by storingand processing heaccumulated water n the turbine building.).

Countermeasure 13] Considerationof recovering heat exchange function for the reactor(installingheat exchangers)

Risk [5]: Possibilityof prolongedwork in high dose level area (keep countermeasures 9]and[12])

(Unit 2)

Countermeasure 14]: Continue coolingby currentminimum injection rate.

Countermeasure 16]: Continue considerationand implementationof sealing measure todamaged ocation. Implement coolingmeasures similar o those for UnitsF1 and F3 oncethe damagedlocationis sealed.

Risk [2]: Possibilityof prolonged work sealingthe damaged location (continuecountermeasures 12] and[14]

Factor a. analysis:Countermeasure [9] will satisfy Factor a. Obstacles to flooding of the containments, e.g.,radwaste processing should be given priority so that flooding can begin as quickly aspossible.

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b. Factor: Provide functional and reliable backups, including power sources, for eachof the systems being used; ensure backups can be employed in time to maintainadequate cooling.

Countermeasure[8]: Install interconnecting ines of offsite power soon

Countermeasure 22] Continue waterinjection by Giraffe , etc reliabilitymprovement(enhanceddurabilityof hoses)/switch to remote-controlledoperation)

Factor b. analysis:

Countermeasures [8] and [22] address redundancy. The Consortium encourages TEPCOto provide backup means of cooling, including backup power sources, that can beemployed in time to provide adequate cooling should the primary means fail. TEPCOmay consider using probabilistic risk assessment to determine countermeasures thatprovide the greatest risk reduction.

c. Factor: Establish a functional and clean water source of sufficient capacity toensure adequate on-site cooling water.

Countermeasure 12] Considerationand implementationof measures to hold down waterinflow (e.g. circulatingwater back into the RPV by storingandprocessingthe water in theturbinebuilding)

Countermeasure 23]: Add cooling function to normal fuel pool coolingsystem andcontinue injecting water for unit F2.

Countermeasure 24]: Examinationfor and implementationof restorationof normal coolingsystem for unitsF1, F3, and F4 .Factor c. Analysis:

Stabilization countermeasures are appropriate for this Factor. However TEPCO shouldalso assess the reliability of the ultimate fresh water source including the delivery system

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(water piped from nearby reservoir and the onsite delivery system to the reactors andspent fuel pools). The consortium recommends that TEPCO consider adding a backupmeans of adding water to the normal fuel pool cooling systems for the 1F2 spent fuel pool.Restoration of the cooling function of fuel pool cooling system would also increasereliability.

The Consortium recommends redundant delivery systems to each of the seven fuellocations requiring emergency cooling.

The Consortium acknowledges the need to circulate water back to the RPVs to improvethe waste-water generation situation. When recirculation methods are put into place, therewill be increased risk of debris in re-circulated water interfering with cooling. TEPCOshould address this concern in design of the recirculation systems. A once-through wateraddition method should still be maintained as a backup.

TEPCO should also address the possibility of biological fouling of reactors, spent fuelpools, containments, water recirculation systems, and water delivery systems.

d. Factor: Establish the ability to reliably add makeup water to each spent fuel pooland maintain spent fuel pool temperatures less than 100 degrees Celsius

Countermeasure 22]: Continue water injectionby Giraffe , etc reliability mprovement(enhanceddurabilityof hoses)/switch to remote-controlledoperation.)

Factor d. analysis:

It is not clear how TEPCO is reliably adding water to the 1F1 spent fuel pool and the basisfor concluding that adequate cooling is occurring. It is our understanding that reportedtemperatures are based on thermography from above, which indicates only the surfacetemperature of the first obstacle encountered. This would not seem to be a reliableindicator of actual spent fuel pool temperature. Also, the basis for determining how muchwater is actually being added to the 1F spent fuel pool is unclear, considering the almostcomplete obstruction by the collapsed roof shown in photographs.

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TEPCO might consider countermeasures to establish reliable temperature indication forthe spent fuel pools.

Factors used to evaluate Essential Function 2 (Maintain reactors and spent fuel poolssub-critical and adequately shielded)

e. Factor: Establish reliable means, either chemical or geometric, to maintain eachreactor and spent fuel pool sub-critical.

Factor e. analysis:

This factor is not satisfied.

The TEPCO Roadmap is silent on maintaining the fuel sub-critical Fuel movement orstructural degradation may potentially increase reactivity. Actions to further prevent ordetect inadvertent criticality would improve confidence that inadvertent criticality will notinhibit recovery actions.

TEPCO may consider establishing countermeasures that will assure the fuel in 1F1, F2,and 1F3 reactors is subcritical.

The fuel configuration in 1F1, 1F2, and 1F3 spent fuel pools has not been verified.

One cooling water sample on the 1F4 spent fuel pool indicated that criticality had notoccurred in the pool. Additional samples would enhance the validity of this single sample.Visual observations indicate that the fuel is intact in the racks.

f. Factor: Establish adequate shielding or zone of protection around reactors andspent fuel pools to allow for safe execution of the Roadmap countermeasures.

Factor f. analysis:This factor is not satisfied. The Roadmap considers dose rates at or beyond the siteboundary. There is little consideration in the Roadmap for providing shielding to theworkers on site.

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Factors used to evaluate Essential Function 3 (Ensure structural integrity for all units(e.g. containment and spent fuel pools)

g. Factor: Preclude detonation in primary containment atmosphere by establishing anon-combustible atmosphere in the primary containment

Countermeasure 15]: Continue prevention of hydrogen explosion by nitrogen injectionintothe PCV.

Factor g. analysis

This factor is satisfied for 1F1 and should be continued.

This factor is not satisfied for 1F2 and 1F3. Given that TEPCO has reported that normalinjection paths may be unavailable, it becomes necessary to evaluate alternate methodsfor injecting nitrogen into 1F2 and 1F3 PCVs. When evaluating paths for injecting nitrogeninto 1F2 and 1F3 PCVs, the consortium recommends against considering the RPV wateraddition flow path for nitrogen injection, as a nitrogen blanket in the RPV would reducesteam cooling of the core material.

Ifnitrogen injection and containment atmospheric sampling are not feasible, verifyanalytically the steam inerting and/or leakage is sufficient to not have an explosivemixture.

h. Factor: Establish reasonable assurance of Reactor Pressure Vessel, PrimaryContainment, and Spent Fuel Pool integrity

Countermeasure 20]: toleranceevaluationis especiallyneeded for F4. A certainlevel ofseismic tolerancehas been confirmed.

Factor h. analysis

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TEPCO Roadmap structural concerns related to spent fuel pools are primarily focused onthe 1F4 spent fuel pool. However, the structural integrity of reactor building 3 alsoappears to be degraded from the explosions. Although spent fuel pool 1F4 may havemore significant consequences because the full core was offloaded from 1F4, theconsortium also encourages TEPCO to assess the structural integrity of the 1F3 spent fuelpool, and confirm the structural integrity of spent fuel pools 1F1 and 1F2.

TEPCO is encouraged to consider adding a corrosion control countermeasures topreserve the integrity of the RPV primary containment, and spent fuel pools. Vesselmaterials have been exposed to water chemistry that can accelerate stress corrosioncracking SCC) and general corrosion in the RPV. This is a particular concern formaterials and welds in the RPV which are known to be susceptible to failure by SCC.While guillotine fractures due to SCC are not expected ifstress levels are low, acircumferential SCC crack could increase susceptibility to failure in a transient or seismicevent. The Consortium is not aware of any attempts to characterize or control thechemistry of water injected into the RPV to mitigate corrosion. Actions to characterize thecorrosion environment and countermeasures to reduce risk of corrosion failures (e.g., pHadjustment or addition of specific corrosion inhibitors) should be considered.

Factor used to evaluate Essential Function 4 (Reliable Indication of essential parameters)

L Factor: Establish reliable means to determine key parameters associated withactual or potential large releases

i. Instrumentation to confirm reactors and spent fuel pools are sub-critical,ii. Area Radiation, gaseous and liquid release detectors,

iii. RPVIDW/SP level, RPV/DW pressure indications, RPV/DW/SP temperaturesiv. Spent fuel pool level, temperature indications

Countermeasure 57]: Monitoringseawater,soiland atmosphere within the siteboundary(25 locations)

Countermeasure 58]:Monitoringthe radiationdose at site boundary(12 locations)

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Countermeasure 59]: Considerationof monitoringmethods in evacuation orderplannedevacuation emergency evacuation preparationareas.

Countermeasure 60] Considerationand implementation of monitoringmethods inevacuationorder/plannedevacuation emergency evacuation preparationareas(incooperationwith national/prefectural/municipal overnments)

Countermeasure 61]: announce accuratelymonitoringresults of long half life residueradioactivematerialssuch as cesium 137

Countermeasure 62]:Monitoringof homecoming residences(in cooperationwithnational/prefectural/municipal ovemments)

Countermeasure 63]: Examination and implementationof necessary measures oreduce radiationdose (decontaminationof homecoming residences and soil surface) (incooperationwith national/prefectural/municipal overnments)

Factor i. analysis

This factor is not satisfied. The Roadmap places an emphasis on radiation readings offsite but little emphasis on determining essential parameters to monitor the state of thereactors and spent fuel pools.

TEPCO should evaluate what instrumentation indications are essential to successfullycompleting stabilizing actions e.g., SFP level and temperature, RPV/PCV water level,temperature, pressure) and determine what backups or contingency plans are necessaryshould these indications fail. The Roadmap countermeasures focus on radiationmeasurement, but do not address instrumentation necessary to take proper plantstabilization actions. Also, the recovery of inoperable installed instrumentation should besought.

Factors used to evaluate Essential Function 5 (Terminate (or render insignificant)uncontrolled radioactive releases)

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j. Establish the means for containment of significant external leakage (e.g. primarycontainment leakage) for portions of the plant (SFPs or reactor units) with crediblepotential for energetic releases of significant quantities of radioactive material.

Countermeasure 29]: identify leakage path andexamine and implement preventativemeasures

Countermeasure[30]: Transferringaccumulated water to facilities that can store it(condenserand Centralized Waste Treatment Facility)

Countermeasure 31]: preparingdecontaminationand desaltof transferredaccumulatedwater

Countermeasure 32]: preparing o installtanks

Countermeasure[33]: Preparing o store with tanks and barges

Countermeasure[34]: Preparing ordecontaminationand desalt of contaminatedwater

Countermeasure 35]: Preparing o install reservoir

Countermeasure 36]: Preparing o decontaminatesub-drainagewater afterbeingpumpedup.

Countermeasure 37]: Utilization of "CentralizedWaste Treatment , to store water

Countermeasure 38]: Installwaterprocessing acilities; decontaminateand desalt highlycontaminatedwater and store in tanks.

Risk [7]: Possibilityof delay in installingwater processingfacilitiesor pooroperatingperformance of the facilities.

Countermeasure 39]: Examinationand implementationof backup measures (installmentof additional anks or pools or leakage preventionby coagulator,etc)

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Countermeasure 40]: Increasestorage capacityby adding tanks, barges,Megafloat,etc.

Countermeasure 41]: Decontaminatingcontaminatedwater using decontaminates obelow acceptable criteria

Countermeasure 42]: Expansionof additional anks to store high radiation evelcontaminatedwater

Countermeasure 43]: Continuationandreinforcementof decontaminationand desaltofhigh radiation evel water

Countermeasure 44]: Continuationandreinforcementof decontaminationand desalt oflow radiation evel water.

Countermeasure 45]: Reuse of processedwateras reactorcoolant.

Countermeasure 46]: Decontamination o the level below criteria evel.

Factor j. analysis:

When put in place these water management countermeasures should satisfy this factor.

k. Factor: With regard to activities in close proximity to the site, consider measuresto minimize further spread of contamination (e.g., covers or resin spray oversignificant sources of loose contamination at the plant)

Countermeasure 47]: Inhibit scattering of radioactivematerialsby full-scale dispersioninhibitorafter confirming its performanceby test.

Countermeasure 48]: Preventrainwater ontaminationby dispersioninhibitor

Countermeasure 49]: Removal of debris

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Offiuial Use Oniy - Sensitive Internal InformationCountermeasure 50]: Examinationand implementationof basic design forreactorbuildingcover full fledged measure (containerwith concrete roofand wall, etc.)

Countermeasure 51]: Considerationof solidification,substitutionand cleansing ofcontaminatedsoil (mid-term issues)

Countermeasure 52]: Improvement of work condition by expandingapplicationanddispersionof inhibitors o the groundand buildings.

Countermeasure 53]: Continue removal of debris.

Countermeasure 54]: Begin installingreactorbuilding cover (with ventilationand filter)

Risk [8]: Considerablereduction in radiationdose is a prerequisite o launch construction.

Countermeasure 55]: Complete installingreactorbuilding covers (Units 1, 3, and 4)

Countermeasure 56]: Begin detaileddesign of full-fledged measure (containerwithconcrete roof and wall, etc.)

Factor k. analysis:

When completed these countermeasures could be effective in satisfying the factor.

Organizational Risks and Considerations:

Understandably TEPCO did not include organizational risks and considerations in theirRoadmap. The Roadmap is primarily a technical document. Nevertheless, the NRC hasincluded suggestions regarding organizational issues that, ifconsidered, may enable moreefficient and effective implementation of the Roadmap. These organizational suggestions mayalso improve the safety of the facility.

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Organizational issues associated with the Roadmap are directly related to safety. Thoseorganizational issues are: 1) ensuring a safety culture is maintained throughout the stabilizationand recovery at the site and 2) providing independent oversight.

As the site transitions from crisis conditions to stable conditions, itwill require a focus onmaintaining a safety culture at the site, especially with the influx of a large non-nuclear trainedworkforce. Minimizing human error is essential for both public safety and the safety of workersat the site. Human conditions for workers are highly important to ensure safe work practices.Human error can be further minimized by the development and use of procedures, by trainingworkers, and practicing work activities on mock ups before the activities are actually carried ou tin the plants.

As Fukushima Daiichi transitions from crisis conditions to stable conditions, providing strongindependent oversight is essential. Activities that could affect criticality, emergency response,core conditions, heat removal, radiation exposure, structural stability and other safety elementsmust be rigorously reviewed through independent oversight that includes written safetyevaluations. A special licensing and safety review process will likely be needed. This processmay include separation of regulatory activities for Fukushima Daiichi in order to avoid anyadverse impacts on operating Japanese reactors. Keeping accurate records of activities will benecessary to help with the ultimate decommissioning of the site. In the long term developingand approving a Safety Analysis Report and technical specifications would be beneficial.

TEPCO will need to ensure organizational reliability within their own organization so that thereremains a safety focus on Fukushima Daiichi while continuing safe operations of the otherJapanese nuclear sites.

* The United States Consortium of Industrial and Governmental Organizations was establishedto provide advice and assistance to the people of Japan in an effort to stabilize and improveconditions at the Fukushima Daiichi Reactor Site following the earthquake and tsunami onMarch 11, 2011. The Consortium includes:

General Electric HitachiInstitute of Nuclear Power Operations

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Naval ReactorsUS Department of Energy/Nuclear EnergyUnited States Nuclear Regulatory Commission

To view the TEPCO Roadmap follow the link below:httr:llwww.tepco.co.*ip/en/press/corp-com/release/l 1041707-e.html

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april 29th, 2011 - consortium of industrial and governmental organizations analysis of tepco roadmap...

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