U. S. DOE Experience with D&D of EBR-2 and FFTF
Andrew Szilagyi
US Department of Energy
Office of Environmental Managementfor theSecond Expert Panel on Monju Decommissioning
Tsuruga, Japan, 19 July, 2017www.energy.gov/EM1

Experimental Breeder Reactor-2
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1964: Full Power
1994: Shutdown
1996: Defueled
2001: Bulk Sodium Removed
2015: Reactor Entombed
2019: Start Dome Demolitionwww.energy.gov/EM2

Fast Flux Test Facility••••••

1982: Full Power
1992: Shutdown
1995: Defueled
2005: Bulk Sodium Removed
2007: Deactivated2030’s: Final Decommissioning: Entombment
Anticipatedwww.energy.gov/EM3

Project Phases• Planning• Project Strategic Objectives• Project Execution Planning• Supporting Plans• Deactivation• Fuel Removal, Washing, and Storage• Sodium Draining and Residual Sodium Removal, Passivation, and Storage• Deactivation of Structures, Systems, Components, Materials• Surveillance and Maintenance Waiting for Final Decommissioning• Final Decommissioning• Entombment• Demolitionwww.energy.gov/EM4

Strategic Objectives• Deactivation End State Definition (depends on if continuing directly tofinal decommissioning or if the facilities will sit idle for many years)• Final Decommissioning End State Definition (Green Field, Brown Field,Entombed)• Environmental Evaluations; in the U.S., this is the basis and justification
for the chosen final End State• Sequence for Deactivation and Decommissioning of Major Site
Facilities (example: electrical supply routing on the site may be
important if power is needed to be retained in some buildings whenothers are isolated or demolished)• Individual demolition projects can include several facilities associatedwith a major buildingwww.energy.gov/EM5

Individual Project Plans•

Characterization••••Radiological contamination, airborne, and direct radiation
Chemical and Hazardous Materials
Physical (use of LIDAR for inaccessible areas)

Project Baseline•

Scope• deactivation, demolition, entombment• number of buildings in a single project•

Schedule• Will depend on many site limitations and available resources, need for technology
development, testing of methods, and others•

Cost• Detailed activity-based estimate• Basis of estimate assumption must be documented•

Technology and Demonstration Needs•••

Adaptation of existing technologies (preferred)
Development of new technology for unusual situations

Project Risk Assessment•••

Risk Identification that could have an effect on the ability to conduct the project activities
Chances of Occurrence
Methods for Avoidance and/or Mitigationwww.energy.gov/EM

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Supporting Plans

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Regulatory Compliance
Worker Safety
Training of Workers for D&D activities
Environmental Protection
Stakeholders, Public, and Local Government Communication
Emergency Responsewww.energy.gov/EM7

Fuel Removal & Washing• From an FFTF Review• Fuel removal rate will be controlled by the rate of washing• At Super Phoenix, the fuel washing process was based on injection within thewashing pit of water mist and C02• At FFTF water vapor and argon were planned• The water mist and CO2 would be much faster• The washing schedule will be controlled by the availability of sufficient storagecasks for the fuelwww.energy.gov/EM8

FFTF Draining••••

All bulk sodium was drained (except for cold traps) and stored in 4 large tanks at theFFTF site pending future use
Draining of reactor vessel required the drilling of a 3/4” hole between the highpressure and the low pressure volumes near the bottom of the reactor vessel.
Piping changes made to NaK systems to allow mixing of NaK with primary sodium toassure complete removal of NaK.
Used a one-third size mockup of the reactor vessel to demonstrate use of superheated steam to react residual sodium

www.energy.gov/EM9

Sodium Treatment Methods(Not one method works for all of it)
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Moist CO2 for passivation (but see next viewgraph)
Superheated Steam for non-passivated sodium
Acidic aqueous solution for passivated and non-passivated sodium andNaKSaturated steam/condensate treatment for heat exchangers
Important Lesson Learned: An attempt to use citric acid treatment to treat
sodium in a network of pipes led to excursions of increasing intensity withmovement of treatment solution back and forth between branches.
Ultimately, this resulted in a larger reaction of sodium and water moving aslug of water rapidly down a pipe and against a dead end, causing a breachof the piping by water hammer.
Lessons from this event are in the reference titled: EBR-II D&D Update—
September 2012 CWI Completes Treatment of Primary System Sodium

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www.energy.gov/EM10

Pros and Cons of Passivation(moist CO2)
•PROS
• Stabilizes sodium by creating a bicarbonate crust 3.9 in (10 cm)
deep over the remaining reactive sodium• Good for long term in-situ storage of sodium•

CONS• Creates an approximate 3.9 in (10 cm) thick hard crust over thesodium hindering further treatment of the sodium using moist
CO2 or superheated steam treatment methods• In order to treat the sodium, the bicarbonate crust must betreated through erosion, high heat, or acid.
• Much easier to treat non-passivated sodium

Passivated Sodium

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www.energy.gov/EM11

Deactivation
Example of Deactivation Planning
FFTF-25070 Revision 0, Fast Flux
Deactivation End Points CriteriaDefinition•Deactivation: Placing a facility in a stableand known condition including theremoval of hazardous and radioactive
materials to ensure adequate protectionof workers, public health and safety, andthe environment, thereby limiting thelong-term cost of surveillance andmaintenance.

•Same as IAEA’s “Transition fromOperation to Decommissioning”

FFTF – 25070 Table of Contents
1.0 Introduction
2.0 Background
3.0 End Points Methodology
4.0 FFTF Deactivation End Points
4.1 Applicable Building Structure and Areas
4.2 End Point Criteria
4.2.1 Fuel Off Load
4.2.2 Sodium Drain and Disposition
4.2.3 Alkali Metal Residuals
4.2.4 Special Components
4.2.5 Systems Shutdown
4.2.6 Hazardous Materials
4.2.7 Administrative Items
5.0 Remaining Hazardous Materials
6.0 Regulatory Framework
7.0 D&D Planning
8.0 References
www.energy.gov/EM12

Surveillance & MaintenanceFFTF Example: Table of Contents
DOE/RL-2009-26 Revision 0, Surveillance andMaintenance Plan for the Fast Flux Test Facility

www.energy.gov/EM13

Final Decommissioning
FFTF Example••

Environmental Impact Statement issued in November 2012; Alternatives
Evaluated were:•No Action•
Entombment•
RemovalThe Preferred Alternative selected was “Entombment” and consists of thefollowing actions:• Removal of all above grade structures• All below grade facilities/components filled with grout to immobilize
radioactive and hazardous constituents• Engineered barrier to be placed over area
• Remote-handled “special components” processed at Idaho NationalLaboratory and waste returned to Hanford• Bulk sodium (currently in storage at FFTF) would be used as product at theWaste Treatment Plant at Hanford

www.energy.gov/EM14

EBR-2 Final Decommissioning
Reactor Entombment

Main Floor above the Reactor

Reactor is now Entombed with Grout

Entombment
Conceptwww.energy.gov/EM15

Lessons Learned-1• Expect the Unexpected! You will meet situations that were not planned; such as
physical configuration different than documented, contamination or high radiation
not anticipated, air flow in the wrong direction, or many other kinds.
• It is important to accelerate the transition from an operating culture to thedecommissioning culture and mission. Until this is done, progress will be delayed.
This will require re-training of workers that wish to stay and hiring others withneeded skills. Engineering and work practices and procedures will need to change
for the new work and mission environment.
• Understand and plan for the safety of workers and the public for which manypotential threats will be different than during operations.
• Regulatory oversight will need to adapt to the changes in mission, conditions, typesof activities, and other issues that differ considerably from previous operations.
Many of the previous issues will also remain.
• Inform Stakeholders as early as possible of future uses and end states. Continue tocommunicate as progress is made.
• Understand the need for different and evolving technologies; encourage innovation.
www.energy.gov/EM16

Lessons Learned-2• Characterization is essential to project planning• Several methods for sodium removal and processing will be needed. Do not plan onone.
• The use of mock-ups to test and qualify sodium removal methods and processes
proved to be valuable• Record knowledge of technical staff prior to their departure• Maintain “as-built” drawings for equipment and systems that will continue to beneeded (recognizing they may be inaccurate)• Maintain spare parts that may be needed to “re-configure” systems for D&D• Maintain records of past operational upsets

www.energy.gov/EM17

Acknowledgements & References•

Acknowledgements•••

EBR-2, Mr. Kirk Dooley
FFTF, Mr. Al Farabee

References
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U.S DOE Hanford Office, Fast Flux Test Facility Closure: Accomplishments and Plans, January
26, 2017.
Idaho Cleanup Project, D&D Sodium Treatment Overview
Experimental Breeder Reactor (EBR-II) D&D Overview
DOE/ID-11398Revision 0, Engineering Evaluation/Cost Analysis for the EBR-II Final End State,January 2010
DOE/EA – 0993, Environmental Assessment, Shutdown of the Fast Flux Test Facility
DO E/RL-2009-26 Revision 0, Surveillance and Maintenance Plan for the Fast Flux Test Facility
FFTF-25070 Revision 0, Fast Flux Test Facility Deactivation End Point Criteria
IAEA-TECDOC-1633, Decommissioning of Fast Reactors after Sodium Draining
IAEA-TECDOC-1769, Treatment of Residual Sodium and Sodium Potassium from Fast Reactors
DOE EM Project Experience & Lessons Learned for In Situ Decommissioning, U.S. Departmentof Energy Office of Environmental Management, Office of D&D and Facility Engineering
EBR-II D&D Update—September 2012 CWI Completes Treatment of Primary System Sodium

www.energy.gov/EM18