REMP Ramblings

2006 RETS/REMP Workshop

Jim Key

Key Solutions, Inc.

www.keysolutionsinc.com

Regulatory Requirementsfor the REMP

• The Radiological Environmental Monitoring Program is Required by 10 CFR 50, Appendix I, Section IV.B.2 and IV.B.3.

• Focus Is On:– Dose to Individuals– Principal Pathways of Exposure

The NRC and REMP

• Radiological Assessment Branch Technical Position , Rev 1, Nov 1979, “An Acceptable Radiological Environmental Monitoring Program”

• Guidance for details of REMP provided in NUREGs 0472, 0473, 1301 and 1302.

The NRC and REMP

• Branch Technical Position Sets Forth an “Acceptable Minimum Radiological Monitoring Program”

• An Acceptable Monitoring Program Does Not Guarantee an Effective Monitoring Program

Original NRC REMP Program Design Was Driven By:

• Monitoring of Human Food Chain– Does not necessarily insure accurate assessment

of environmental impact.– More environmentally sensitive indicators may

be overlooked.

• Assumed Demographics • Assumed Environmental Usage

(Agricultural)• Assumed Likely Critical Exposure Pathways

REMP Program• Based On NRC Assumptions (30 years ago)• Are Assumed Demographics Still Valid at

Your Site?• Is Assumed Environmental Usage Still

Valid at Your Site?• Are Assumed Critical Pathways Still Valid

at Your Site?• Are There Non-Critical Pathways That

Need Monitoring – More Environmentally Sensitive?

Ground Water Grumblings• Average per capita

Consumption of Water is 185 gal/da.

• Subdivision of 50 Houses (3 individuals per house) ~ 10,000,000 gal/yr

• Could Have Significant Effect on Local Aquifer

Ground Water Grumblings

• UFSAR Hydrology Data Decades Old• Consumption from Local Aquifers

– Potential to Modify Aquifer Gradient– Aquifer Flow May Be Retarded or Increased– Result Transport of H-3 in Groundwater Not

Properly Understood

• If in Doubt “Back of the Envelope” Calculations Should be Considered to Determine Need for Additional Study

Spills and Thrills

• Need to Review Past Site Contamination Incidents– Attitude Towards On-Site Spills Was Different in Past

• Hot Spills or High Volume Spills– How Much Activity Was Recovered

– How Much Activity Unaccounted For (and Still Out There?)

– What is the Potential for Migration on Site and Off Site?

How Low Do We Go?

Where Did the LLD Number Come From?

• LLDs in Current Guidance Based On

“What (we thought) the technology would be capable of by the time the RETS were in force.”

• Based on 30+ Year Old Technology

How Low Do We Go?

Reg Guide 4.1

“…the detection capability of environmental measurements should be the most sensitive that is practicably achievable for measuring plant-contributed radionuclides in the environment.”

NRC Environmental Reporting Levels

Nuclide Water Airborne Fish Milk Food

pCi/l pCi/m3 pCi/Kg pCi/l pCi/Kg

H-3 20,000

Mn-54 1,000 30,000

Fe-59 400 10,000

Co-58 1,000 30,000

Co-60 300 10,000

Zn-65 300 20,000

Nb-95 400

Zr-95 400

I-131 2 0.9 3 100

Cs-134 30 10 1,000 60 1,000

Cs-137 50 20 2,000 70 2,000

Ba-140 200 300

La-140 200 300

Annual Doses Associated With Reporting Levels

Nuclide Water Airborne Fish Milk Food

mrem mrem mrem mrem mrem

H-3 2.1

Mn-54 10.2 8.8

Fe-59 9.9 7.1

Co-58 11.0 9.5

Co-60 8.8 8.4

Zn-65 6.2 6.5

Nb-95 6.1

Zr-95 9.0

I-131 9.2 14.6 13.8 14.9

Cs-134 7.0 11.3 3.2 13.9 10.0

Cs-137 10.1 18.1 4.8 14.1 17.0

Ba-140 11.3 16.9

La-140 13.5 11.8

NRC Environmental LLDs

Nuclide Water Airborne Fish Milk Food Sediment

pCi/l pCi/m3 pCi/Kg pCi/l pCi/Kg pCi/Kg

H-3 2000

Mn-54 15 130

Fe-59 30 260

Co-58 15 130

Co-60 15 130

Zn-65 30 260

Nb-95 15

Zr-95 15

I-131 1 0.07 1 60

Cs-134 15 0.05 130 15 60 150

Cs-137 18 0.06 150 18 80 180

Ba-140 15 15

La-140 15 15

Annual Doses Associated With Environmental LLDs

Nuclide Water Airborne Fish Milk Food Sediment

mrem mrem mrem mrem mrem mrem

H-3 0.21

Mn-54 0.15 0.04

Fe-59 0.74 0.19

Co-58 0.17 0.04

Co-60 0.44 0.11

Zn-65 0.62 0.08

Nb-95 0.23

Zr-95 0.34

I-131 4.59 1.14 4.59 8.92

Cs-134 3.48 0.06 0.41 3.48 0.60 4.8E-03

Cs-137 3.63 0.05 0.36 3.63 0.68 2.0E-03

Ba-140 0.85 0.85

La-140 1.01 0.59

How Low Do We Go?

• Ideally Environmental Detection Limits Should be a Small Fraction of the Reporting Limits

• This Implies LLDs of 1% – 5% of Reporting Limit

• NUREGs Specify (Drinking Water)– 10% for Tritium– 36% for Cs-137– 50% for I-131

Tritium LLDShould We Go Lower?

• Yes – Why?– Reg. Guide 4.1 – “the detection capability of

environmental measurements should be the most sensitive that is practicably achievable…”

– State-of-the-Art Has Improved Dramatically in 30 years.

– Public Relations– Must Get Out of Reactive Mode

Where Do We Stop?

• Depends – How Paranoid Are You?

Tritium – How Low Do We Go?

2000 pCi/L

1000 pCi/L

500 pCi/L

400 pCi/L

200 pCi/L

100 pCi/L

What Is Good Stopping Point?

% Rpt Lmt Comments

2000 pCi/L 10 % Current Requirement

1000 pCi/L 5 % Could Do Better

500 pCi/L 2.5 % Good

400 pCi/L 2 % Good

200 pCi/L 1 % Some Plants Are Currently Measuring In This Range 100 pCi/L 0.5 %

Washing Vegetation

• IAEA Technical Report 364 Lists Decontamination Factors for Food Preparation

• Factors Provided For:– Total Contamination of Plant

(root and leaf)– External Contamination

(deposition on leafy portion)

Decon Factors for Washing(External Contamination)

Sr Cs I

Cabbage 0.9 0.5

Cauliflower 0.05 – 0.2 0.03

Lettuce 0.2 – 1.0 0.1 – 0.5

Spinach 0.2 0.2 - 0.9 0.07 – 0.8

To Wash or Not to Wash?

• RETS-REMP Steering Committee Recommendation– Wash if used for human

consumption.– Do not wash if used for animal

consumption.

• Caveat– Important to Maintain Consistency

for Purposes of Historical Comparison

There Are Others Out There…

• NRC and EPA Regs Are Not the Only Requirements

• Don’t Forget State Environmental Regs

• One Utility Hit By Recent Change (2002) in State Regs Which Required Reporting of Any Environmental Results Above LLD Background

Meteorology

• How Old is the Met Data Used to Generate Your /Q and D/Q?

• FSAR Values Probably 20 – 30 Years Old

• How Many Years of Met Data Are You Using for /Q and D/Q?– 1 Year? – Should Update Annually– 5 Years? – Good But How Old?

Meteorology

• Does Your /Q and D/Q Still Adequately Characterize Current Atmospheric Transport?

• Can You Prove It?– Need to Look at Wind Rose Data– Need to Look at Stability Class Frequency

• Be Prepared to Answer this Question…

• Industry Has Been Content to Carry Around REMP Box as Defined by Regulatory Guidance– Assumed No Need to Look Outside

of Box

– Is Current Guidance Too Narrowly Focused? – Could Be

• Time to Think Outside the REMP Box