source term challenges and use of innovation for solutions

Source Term Challenges and Use

of Innovation for Solutions

IIS Benchmarking Meeting

Hot Springs, AR

June 2, 2015

John Moser

Lasalle Station

Unique Challenges

High source term plants

◦ CRE performance in lower quartiles

◦ High radiological risk activities performed

more frequently than at other facilities

◦ Higher contamination levels experienced

Failed fuel

Design challenges

◦ ECCS piping

◦ Cavity

Current Conditions

BRAC dose rates

◦ U1

135 and trending lower

◦ U2

245 and trending higher

Fuel integrity

◦ Recent history of failed fuel on U2

Coolant activity

◦ U1 approximately 1E-4

◦ U2 approximately 9E-3

Unit 2 Status

Crud Resins Crud Resins

Shutdown HWC

DZO

NMCA NMCA

Pleated Filters

LTNC

0

2

4

6

8

10

12

14

16

0

100

200

300

400

500

600

700

800

Jun-84 Jun-87 May-90 May-93 May-96 May-99 May-02 May-05 May-08 May-11 May-14

Co

-60 A

cti

vit

y (

µC

i/cm

2)

Do

se R

ate

(m

R/h

r)LaSalle 2

BRAC Milestones Chem Decon LTNCBRAC (alt) Power Uprate OLNC Co-60 Activity

Typical Unit 2 Conditions

Most Recent Refuel – Feb 2015

◦ Valve internals – to 80 Rad/hr/100cm2

◦ Valve internals – to 82 Rem/hr

◦ CRD’s >100 Rem/hr

◦ Vessel nozzles 30-60 Rem/hr

◦ BHD 27 Rem/hr

◦ >1500 mr/hr authorized regularly

Traditional Solutions to Radiological

Challenges Source term reduction

◦ Elimination of hot spots

◦ HRA/LHRA elimination

◦ Improved filtration (temporary)

◦ Reduced inventory of elemental cobalt

◦ Improved clean-up system capacities and

performance

◦ Shielding

◦ Flushing

Enhancing Traditional Solutions

Source term reduction

◦ Hazards of the environment

Remove/eliminate hazards

Remove worker from environment

Improved execution

◦ Improve communication

Precision

Speed

Proposed Permanent Solutions

Off load core and perform full vessel and bottom head vacuuming

Vacuum all guide tubes

Chemical decontamination of RR and RT systems

Fuel cleaning

Cut out and replace BHD

Cut out and replace RR discharge isolation valves

While We Wait

Superhydrophobic compounds

ROV Cavity decontamination robot

DTS filtration module

Custom shielding applications

◦ Condensate demin filter carts

◦ Tungsten tape on instrument lines

◦ High inventory of composite shielding


Nano-technology that prevents

adherence of water and oils to surfaces

◦ Lotus effect

Technology rapidly expanding

Several product lines available

◦ Consumer/industrial grades


Primary chemistry sample sinks

◦ Routinely decontaminated

◦ Rapidly re-contaminated

◦ Non-safety related

◦ Pre-application

55-80 mR/hr

75 mRad/hr/100cm2

◦ Post application (6 months)

20-35 mR/hr

5-50K DPM/100cm2


Expanded use to other sample sinks

Reapplication just performed on primary

sample sinks

◦ Approximately 18 months

Robinson using for dry cask operations

◦ TIP award

Looking for EPRI to qualify for broad use

ROV Cavity Decontamination

Robot Historically high dose rates and

contamination levels

Configuration prevents effective conventional cleaning

60 segments or compartments around circumference

Needed capability to remotely vacuum and brush

Engaged expertise of ROV

◦ Designed specific to LAS


Robot


Robot Results

◦ Dose rates under water after decon 40-60%

lower than initial dose rates

◦ Dose rates upon drain down 15-20% lower

than historical

Reduction in percentage caused by system testing

and subsequent settling

Expanded use to include Nine Mile 2

Open Cavity Filtration

New filtering strategy

◦ DTS system

Filter bank assembly

Self contained

Adequate surface area

◦ Supplement with portable demineralizer

Underwater cavity decontamination

◦ Suction provided by DTS system

Scope of DTS Use

Captured nozzle flushing plumes

Utilized as suction source for ROV

decontamination machine

Vacuum source for 56 guide tubes

Vacuum source for top of fuel bundles

Continuous source of cavity volume

cleaning

DTS Simplified Plan

View of DTS Assembly in 8-120B

DTS Suction/Discharge Piping

DTS Filtration Module

Positioning of filter membranes in SCF

Canister


SCF Canister being situated on liner


Top view of SCF liner with canisters

System Performance

5,550,000 gallons processed

Continuous operation from flood-up to drain down

Pressure drop

◦ 14 psi dp at start

◦ 13 psi dp at end

Flow

◦ 900 gpm at start

◦ 815 gpm at end (limited by suction source otherwise 860 gpm))

Dose rates on completion

◦ 6.5 R/hr at cask opening

◦ 3 mR/hr on side of cask

Cost savings

◦ Approximately $300K initial use

◦ Approximately $700K per outage after initial

Radiological Results

Approximately 150 Ci removed

Reduced radiation exposure

◦ 11.2 rem for disassembly reassembly window

(historical average approximately 25 rem)

Dose rates on scorpion did not exceed 5

mR/hr (no flushing required or

performed)

Cavity <50k dpm/100cm2 post decon

DTS Dose Rates – L2R15

0.00

20.00

40.00

60.00

80.00

100.00

120.00

140.00

160.00

0

20000

40000

60000

80000

100000

120000

140000

160000

180000

200000

2/4

/15 0

:00

2/6

/15 0

:00

2/8

/15 0

:00

2/1

0/1

5 0

:00

2/1

2/1

5 0

:00

2/1

4/1

5 0

:00

2/1

6/1

5 0

:00

2/1

8/1

5 0

:00

2/2

0/1

5 0

:00

2/2

2/1

5 0

:00

2/2

4/1

5 0

:00

Cu

ries

Co

60 R

em

oved

DT

S D

ose

Rate

mre

m/h

r

13 of 56 guide

tubes vacuumed

Fuel vacuuming

Start of control

rod guide

vacuuming (11

R/hr @ contact)

Dewatered DTS Dose Rates

Previous U1 Results

Remove Worker from the

Environment Google Glass

Telepresence Robot

Google Glass

Virtual Verification

◦ Virtual Verifier to see the action the

performer will take

◦ Virtual Verifier will monitor the performer in

an area free from distraction

◦ Virtual verifier can monitor up to 6

performers

◦ Performer and Virtual Verifier will maintain

communication utilizing a VOIP phone, radio,

Vocera, etc

Google Glass

Virtual Verification

◦ Performer will identify the correct component to be manipulated, and the card that will be applied

◦ Virtual Verifier will agree or disagree with the intended action

◦ Virtual Verifier will take a screen shot of the component in the correct position with the tag applied

◦ Screen shots will be printed and kept with the OOS package or saved on a network drive

Google Glass

Application

◦ Verification during Rx hydro

◦ Field supervisor in WEC and EO in field

◦ Video link to use of virtual verification

E:\

Telepresence Robot

Provides live video and audio streaming

Operated from an ipad

Evolution monitored

◦ Replace Shepherd-89 calibrator sources

40 milli-Curie (mCi) Cs-137

90 Curie (Ci) Cs-137 sources

Tasks performed

◦ Placekeeping

◦ Verification

◦ Oversight

Telepresence Robot

Presentation Title 36

Telepresence Robot

Improving Communication

Vocera◦ Wide scale deploymention

390 personnel

◦ Permanent wifi installed in both reactor buildings Includes over 100 cameras

◦ Temporary hot spots installed in turbine building

◦ Multidiscipline use RP

Operations

All maintenance disciplines

GE

Rx services

OCC/Senior Leadership team

◦ Performed comprehensive survey of users

Improving Communication

Vocera (cont’d)

◦ Survey results

Average efficiency improvement of 27 minutes per

shift per person (3159 person hours)

Immensely improved communication

Favored features

Hands-Free

Call by Name

Push to Talk

Find a person by location

Broadcast to a group

source term challenges and use of innovation for solutions

Documents