Routine Radiological
Environmental Monitoring
Ronald Warren
Ecological & Environmental Monitoring
National Security Technologies, LLC
Community Environmental Monitoring Program Workshop
July 26, 2011
Overview
• Routine Radiological Environmental Monitoring Plan
(RREMP) overview
• Operations evaluations against regulatory limits
• Evaluation that indicated soil re-suspension less than
National Emissions Standards for Hazardous Air
Pollutants (NESHAPs)
• Standards vs. RREMP results
• NESHAPs standards vs. results
• Compliance is demonstrated at the on-site locations, so
the off-site dose is much less
85FY11– 07/26/2011 – Page 2
Page 2
Page
2Title
Log No.
2011-226
Routine
R
Radiological
R
Environmental
E
Monitoring
M
Plan
P
• Identifies requirements for radiological
monitoring at Nevada Site Office facilities,
primarily the Nevada National Security Site
(NNSS)
• Focuses on
– the need to ensure that the public and
the environment are protected,
– that compliance with the letter and the
spirit of the law is achieved, and
– that good land stewardship is
practiced.
• Uses a decision based approach to identify
the data that must be collected and
provides Quality Assurance, Analysis, and
Sampling Plans which ensure that
defensible data is generated.
85FY11– 07/26/2011 – Page 3
Page 3
Page
3Title
Log No.
2011-226
Pathway Approach
• Inhalation (Air)
• Ingestion
– Groundwater
– Game Animals
• Direct Exposure
(External Dose)
85FY11– 07/26/2011 – Page 4
Page 4
Page
4Title
Log No.
2011-226
Pre-Operational Evaluations
• Projects with a potential for airborne
radionuclide emissions are evaluated
(modeled) in accordance with 40
CFR 61 for the potential to cause a
0.1 mrem dose to the public under
the assumption no pollution controls
are in place.
• If the modeled emission exceeds 0.1
mrem, the regulator is required to be
involved with the design, and
monitoring will likely be required
(e.g. JASPER).
85FY11– 07/26/2011 – Page 5
Page 5
Page
5Title
Log No.
2011-226
Modeling of Potential Off-site Dose
• For potential emissions (before a new potential emission
source is created to determine off-site dose)
• To estimate dose from actual emissions because
concentrations of radionuclides from most emissions are so low
they cannot be measured even relatively near the emission
source.
How do we know modeled results are valid
(conservative)?
85FY11– 07/26/2011 – Page 6
Page 6
Page
6Title
Log No.
2011-226
Modeled vs. Measured Results
CAP88 Predicted Nuclide 1
1.0E-03
CAP88 Predicted Nuclide 2
Nearest Of f site Resident
Concentration in Air (pCi/m3)
1.2E-03
8.0E-04
6.0E-04
4.0E-04
Observed Nuclide 1
Observed Nuclide 2
Trendline for CAP88 Prediction
Mean MDC
2.0E-04
0.0E+00
0
10
20
30
40
50
Distance from Release (km)
60
70
CL for U-233, 234, 235 = 7.1E-03 pCi/m3
85FY11– 07/26/2011 – Page 7
Page 7
Page
7Title
Log No.
2011-226
Modeled vs. Measured Results
(continued)
at Gate 700 S Sampler
1.0E-14
1.0E-15
1.0E-16
1.0E-17
1.0E-18
1.0E-13
YEAR
Gate 700 S Annual Mean
CAP88 Prediction for Gate 700 S
Error bars extend from minimum to maximum of measured values.
239+240Pu
CL
Concentration in Air (µCi/mL)
Concentration in Air (µCi/mL)
239+240Pu
at Sedan N Sampler
1.0E-14
1.0E-15
1.0E-16
1.0E-17
YEAR
Sedan N Annual Mean
CAP88 Prediction for Sedan N
CL
Error bars extend from minimum to maximum of measured values.
85FY11– 07/26/2011 – Page 8
Page 8
Page
8Title
Log No.
2011-226
Air Monitoring
Air Particulate Sampling
Atmospheric Moisture Sampling
Air Sampler – Solar Power
Air Sampler – Line Power
Emergency Response
(e.g. wildfires) or for
Special Projects
85FY11– 07/26/2011 – Page 9
Page 9
Page
9Title
Log No.
2011-226
Number of Sample/Measurement Locations
Air & Direct Radiation Monitoring
Network Evolution
220
210
200
190
180
170
160
150
140
130
120
110
100
90
80
70
60
50
40
30
20
10
0
1992
Air Particulate Stations
HTO Stations
TLD Stations
1997
2002
Year
2007
2012
85FY11– 07/26/2011 – Page 10
Page 10
Page
10Title
Log No.
2011-226
Surface Contamination
Air Monitoring Stations
85FY11– 07/26/2011 – Page 11
Page 11
Page
11Title
Log No.
2011-226
239+240
Pu Annual Mean Trends
239+240Pu Annual
Mean Trends
Average
Trend
Lines
for
Locations With > 15-Year
Average Trend Lines for Locations With ≥ 15-Year Histories since 1971
Histories Since 1971
250
Areas 1 & 3
Area 5
200
3 to 9% avg.
annual
decrease
Areas 7, 9, 10 & 15
10-18 µCi/mL
Other Areas
10% of CL
150
100
50
0
1971
1981
1991
2001
2011
Year
85FY11– 07/26/2011 – Page 12
Page 12
Page
12Title
Log No.
2011-226
3
H Average
Trends
by Group
Area Group
H Average
Trends by Area
3
Average Trend Lines for Locations With ≥ 7-Yr Histories since 1990
Data before 1999 adjusted; Schooner omitted
15
Area 1
Area 3
x 10-6 pCi/mL
Area 5
Areas 6-9-10-12
10
Areas 15-16-18-20
Areas 23-25
1% of CL
5
~15% avg.
annual
reduction
0
1990
1995
2000
2005
2010
Year
85FY11– 07/26/2011 – Page 13
Page 13
Page
13Title
Log No.
2011-226
Fraction of Limit from Air Pathway
Fraction of Regulatory Limit for
Emissions
Fraction ofAir
Regulatory
Limit for Air Emissions
Off-site MEI Based on CAP88 Modeling
On-site Compliance Station: Highest Annual Average Air Concentration
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
Calendar Year
85FY11– 07/26/2011 – Page 14
Page 14
Page
14Title
Log No.
2011-226
Water Monitoring
Groundwater
Monitoring Wells (ER-OV-01 and -06A)
Surface Water
E Tunnel Ponds
E Tunnel
Out-flow
Water Supply (Last Trails Ranch)
Off-Site Springs
85FY11– 07/26/2011 – Page 15
Page 15
Page
15Title
Log No.
2011-226
Groundwater Monitoring
Surface Water Monitoring
85FY11– 07/26/2011 – Page 16
Page 16
Page
16Title
Log No.
2011-226
Tritium in Onsite Monitoring Wells with
Tritium in Onsite Monitoring Wells with
HistoriesHistories
of Elevated
Concentrations
of Elevated Concentrations
10000
pCi/L
1000
100
PM-1
UE-7NS
10
U-19BH
WW A
10% of EPA MCL
1
1984
1988
1992
1996
2000
2004
2008
2012
Collection Date
85FY11– 07/26/2011 – Page 17
Page 17
Page
17Title
Log No.
2011-226
Pahute Mesa Contaminant Transport Model
85FY11– 07/26/2011 – Page 18
Page 18
Page
18Title
Log No.
2011-226
Biota Monitoring
Game Birds
Big Game
(opportunistic
sampling – e.g.
road kills)
Rabbits
85FY11– 07/26/2011 – Page 19
Page 19
Page
19Title
Log No.
2011-226
Biota Monitoring Sites
85FY11– 07/26/2011 – Page 20
Page 20
Page
20Title
Log No.
2011-226
85FY11– 07/26/2011 – Page 21
Page 21
Page
21Title
Log No.
2011-226
Dose from Animal Consumption
Potential Dose from Consuming One Animal (mrem)
1.0
0.9
0.8
0.7
E Tunnel Chukar
Schooner Cottontail Rabbit
T2 Quail
T2 Jackrabbit
0.6
Sedan Jackrabbit
Area 3 RWMS Jackrabbit
0.5
Area 5 RWMS Jackrabbit
Pu-valley Jackrabbit
0.4
0.3
0.2
E Tunnel Doves
Palanquin Doves
Well U-20n PS#1DDH Doves
Pu-valley Doves
Sedan Doves
0.1
Schooner Doves
Areas 8, 12, & 30 Mtn Lion
0.0
Area 5 Pronghorn
85FY11– 07/26/2011 – Page 22
Page 22
Page
22Title
Log No.
2011-226
Direct Radiation Monitoring
Thermoluminescent Dosimeters
85FY11– 07/26/2011 – Page 23
Page 23
Page
23Title
Log No.
2011-226
ETLD Monitoring Locations
Area 3
RWMS
Area 5
RWMS
85FY11– 07/26/2011 – Page 24
Page 24
Page
24Title
Log No.
2011-226
Estimated
Annual Exposures
Estimated Annual Exposures
Locations
With
10-Year
Histories
Locations
Withat
at Least
Least 10-Year
Histories
1600
Control
Background
Environmental 1
Associated with Legacy Contamination
Waste Operations
1200
mR
A4 Stake A-9
800
A2 Stake N-8
A3 RWMS S
400
0
Year
85FY11– 07/26/2011 – Page 25
Page 25
Page
25Title
Log No.
2011-226
Calendar Year 2010 Radiological Dose
to a Person Breathing Air on the NNSS (Gate 510)
and Eating 20 Jackrabbits from near the Sedan Crater
63.3%
Dose from cosmic and
terrestrial radiation at
Indian Springs,
100 mrem/yr
Dose from natural
radionuclides in body,
31 mrem/yr
8.6%
Dose from inhalation of
decay products from
natural radon,
229 mrem/yr
27.6%
0.5%
Dose from NNSS
emissions to air and
consumption of wildlife
and plants, 1.69 mrem/yr
85FY11– 07/26/2011 – Page 26
Page 26
Page
26Title
Log No.
2011-226
Conclusions
• Concentrations of radionuclides from legacy
contamination show decreasing trends primarily due to
immobilization, dilution, and physical decay.
• On-site operations involving radioactive materials are
evaluated for air emissions.
• Current pathways for radionuclides to off-site public are air
and game animals (no current pathway for groundwater or
direct radiation).
• Concentrations of radionuclides measured in air at on-site
compliance stations and in water at on and off-site
environmental monitoring locations are much less than
limits for exposure to the public.
85FY11– 07/26/2011 – Page 27
Page 27
Page
27Title
Log No.
2011-226