Fermilab
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JLab
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SLAC
LBNL
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BNL
LANSCE
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Argonne
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SNS
1. Field Instruments
Volumetric radioactivity - Ludlum 2241 or 18 meter with 4402 detector (1” NaI) or equivalent
Surface contamination - Ludlum 2241 with GM pancake or equivalent (e.g., TBM P15).
For volume activation, Bicron Analyst with 1.5” X 1.5” NaI probe or Eberline E140 or Ludlum 17704
Frisker Survey Instrument (Pancake GM tube) are used. The Bicron is preferred for detecting volume
activation but magnetized materials and stray static magnetic fields from spectrometers, etc. preclude their use
in some locations.
Smear samples are also taken as indicated by other reasons.
Volumetric activity: Thermo (Bicron) Microrem with low energy option. Plastic (tissue equivalent)
scintillator.
Surface contamination: Pancake GM detector with any appropriate count rate meter.
Volumetric – 2x2 NaI probe with ASP-2e electronics.
Surface Contamination – Pancake probe with Bicron Surveyor M
Volumetric radioactivity: Ludlum 16 meter with 44-2 detector (1” NaI) or equivalent is required. Typically
use Ludlum 2221 meter with 44-20 (3” NaI) detector.
Surface contamination: Ludlum 2224 meter with 43-89 (alpha/beta phoswich) or equivalent.
Ludlum 19 micro-R with 1” NaI detector.
Eberline
o E600-SPA-3 (2X2” NaI)
o ESP-1-HP-260 (GM)
Eberline ASP2e meter with PG2 2mm x 2 inch probe (mini-FIDLER)
Summary:
 For volumetric radioactivity: Most labs (6 out of 7) use a NaI detector with diameter between 1” and 3”. One lab uses plastic
scintillator.
 For surface contamination: Most labs (5 out of 7) use GM counters. One lab uses an alpha/beta phoswich. One lab also does
smear samples, as needed.
SLAC
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Fermilab
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JLab
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SNS
LBNL
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BNL
LANSCE
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Argonne
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2. Direct Field Surveys
Volumetric radioactivity - surface-scan 2”/s over all surfaces for gamma measurements using Ludlum 2241 or
18 meter with 4402 detector (1” NaI) or equivalent with an ambient background of ≤ 600 cpm
Isotopes of interest are high-energy and high-intensity beta-gamma isotopes, e.g., Na-22, Mn-54, Co-57, Co60, Eu-152, etc.
For volumetric radioactivity, a surface scan with the Analyst must be done in a background of < 2000 cpm.
Twice the mean background rate is taken to evidence radioactive material. If the background rate is higher (up
to 3000 cpm), a net count rate of 2000 cpm is taken to evidence radioactive material.
Using the friskers, a net count rate above 50 cpm is taken to evidence radioactive material.
Our isotopes of interest are those typically found at all accelerators; Na-22, Mn-54, Be-7, Co-60, etc.
Volumetric activity: Direct surface measurement; combination static and slow scan technique, in background
< 15 µrem/h.
Surface activity: Swipes counted with pancake GM, or direct scan if item is not activated. [Pancake GM
surveys allowed if PK indicates presence of beta emitters]
Surface scans
Volumetric radioactivity: Surface-scan over all surfaces for gamma measurements using Ludlum NaI meter
with stable background.
Surface contamination: All-surface scan for fixed contamination at 2”/s and 100-cm2-surface swipe for loose
contamination (measure moderate to high-energy beta and gamma with 43-89 probe. Clearance procedure
includes table of maximum background depending on efficiency of probe for isotope of concern.
Isotopes of interest are any and everything, but actinides, C-14, and P-32 most common.
Surface scan, 2 inches/second utilizing Ludlum 19 with ambient background < 13 uR/h.
Isotopes of interest are Na-22, Mn-54, Co-57 & Co-60.
LANSCE Isotopes of interest are same as listed by SLAC, but in addition include Tungsten spallation
products.
Surface scan speed is 2”/s with both instruments.
Ambient background must be less than the following at the survey location:
o SPA-3: 33k cpm max
o HP-260: 480 dpm max
1 minute bkgd must be < 1500 cpm
place probe ~ 1 inch from item and scan while in integrate mode for 1 minute. Large items scan at 5 minutes
per 1 meter^2.
Summary:
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For volumetric radioactivity: All labs do a surface scan in with a designated, low-background value. One lab also does static
measurements. Three labs use a scan speed of 2”/s
For surface contamination: All labs do a surface scan. Two labs also take swipes as indicated.
Four labs noted that isotopes of interest are high-energy, high-intensity beta-gamma isotopes (Na-22, Mn-54, etc). For one lab,
actinides, C-14, and P-32 are the most common. One lab is also interested in tungsten spallation products.
SLAC
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Fermilab
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JLab
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SNS
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LBNL
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BNL
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LANSCE
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Argonne
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3. Release Criteria
Only materials that have non-detectable radioactivity, i.e., indistinguishable from ambient measurement
background, can have unrestricted release.
o Ludlum 1” NaI: net signal ≤ 2 of background signal of detectors; about 120 cpm in a background of
600 cpm. (detection limits = a few pCi/g for isotopes of interest).
See above. Both these threshold values have been determined to correspond to 95 % confidence levels for
determining something to not be radioactive. Our limits represent specific activities of similar magnitude to
SLAC’s.
Release allowed if no activity detected, and PK indicates little likelihood of hard to detect nuclides.
o Microrem: No detectable signal above ambient background – “detectable” defined to have upper
bound of 5 µrem/h net. (sensitivity < 10 pCi/g for nuclides of interest in typical materials)
o Pancake GM: No detectable net signal (“detectable” defined to have upper bound of 100 cpm).
Sensitivity assumed equivalent to DOE β-γ contamination limits.
NaI – Less than Lc in a background of less than 8000 cpm.
Also need PK that material is uniform composition, no likely pure beta/alpha emitters, and most activated
surface is accessible, OR activation calculation showing total activity less than 1000 dpm (powder), 5000
dpm (solid) or 10000 dpm (H-3).
Pancake – less than 10CFR835 release limits for surface contamination
For potentially activated materials, only materials that have non-detectable radioactivity, i.e.,
indistinguishable from ambient measurement background, can have unrestricted release (because they are
non-radioactive material).
Ludlum 1” NaI: net signal ≤ background signal
Ludlum 2224 w/43-89: net signal ≤ surface activity in our release procedure, which references DOE O5400.5
Surface Contamination Limits (the same as Authorized Limits)
Only steel items with a thickness approx. < 2” or concrete thickness approx. < 4” indicating background only
are candidates for unconditional release.
Larger bulk items are considered volumetric release. Volumetric release requires direct scan along with
analytical samples. Volumetric release is specifically authorized by and Radiological Control Division
manager or as outlined in a Record of Decision.
Only materials with no detectable radioactivity shall be free released without any restrictions.
o Based on established LANL/LANSCE NDA release criteria (RP-1 TA-53 DP-312 procedure)
Use “decision level” labeled on meter to decide if radioactivity is present. Typically 100 cpm above bkgd.
Summary:
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For all labs, only materials with no detectable radioactivity (indistinguishable from background) are released.
For surface contamination, all labs use 10 CFR 835 surface contamination release limits
SLAC
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Fermilab
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JLab
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SNS
LBNL
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BNL
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LANSCE
Argonne
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4a. Verification Measurements:
Analytic Sample Measurements
May include portable gamma spectrometry measurements in the field (detection limits around 1 pCi/g for
isotopes of interest).
May include core drill sample measurements with Laboratory gamma spectrometry system with
environmental measurement protocol (detection limits around 0.1 pCi/g for isotopes of interest).
We have used these same verification techniques. We use field gamma spectroscopy, samples, etc. These are
used when we have process knowledge reasons for believing that the activation is nonuniform, etc.
Conducted for the following reasons:
o As part of technical basis study,
o If PK suggests potential for significant (> ANSI screening levels) activity that may not be detectable
through standard survey,
o Release of liquids, finely divided solids, soil and soil analogues.
Methods may include in-situ gamma spectroscopy, samples counted with lab gamma spec (including swipes,
core drillings, liquids, etc.), and lab tritium analysis of swipes, liquids and leachates. Detection sensitivity
defined in technical basis documents.
If any criteria not met, refer to Health Physicist for further evaluation, maybe including gamma spec
Conducted as part of shield block release technical basis study.
Conducted when warranted by process knowledge or for specific release and field applications.
May include portable gamma spectrometry measurements in the field (detection limits around 1 pCi/g for
isotopes of interest).
May include core drill sample measurements with Laboratory gamma spectrometry system with
environmental measurement protocol (detection limits around 0.1 pCi/g for isotopes of interest).
Volumetric release would include direct survey and analytical samples. Brookhaven National Laboratory no
longer has on site analytical measurement capability. Samples are sent off site for analysis (detection limits <
0.2 pCi/g for radionuclides of interest).
We primarily rely on process knowledge but have gamma spectroscopy capabilities if needed.
same as SLAC
not required, but may be done
Summary:
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Most labs use in-field gamma spectrometry if indicated by PK.
All labs use laboratory gamma spectrometry if indicated by PK.
One lab also uses laboratory tritium analysis.
One lab does not have on-site analytical measurement capability and sends all samples off site for analysis.
SLAC
Fermilab
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JLab
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SNS
LBNL
BNL
LANSCE
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Argonne
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4b. Verification Measurements:
Portal Gate Monitor
Plan to use (detection limit of ~1 µCi for Co-60 in the vehicle).
We have a commercial “truck scanner” monitor used as a secondary check on outgoing shipments. Do not
readily have the calibration in hand, but if the monitor trips, a full scale hand survey is done. We don’t trust
this as primary because of self-shielding considerations.
Developing in-situ scrap/waste container monitor. All site waste/scrap metal will be staged in a single
collection area employing dedicated, continuous monitoring of containers. Expected sensitivity is < 1
µrem/h.
Walk-thru portal monitors at doorways as a feel-good step – 3 to 5 microCi sensitivity
We have one, but not in use.
Vehicle monitor has detection limit of 2 nCi Cs-137 in an open vehicle.
Defense-in-depth radiation monitor at facility exit is being replaced, and we will need to establish our new
gate monitor sensitivity. In the past, the alarm threshold was set at 4 sigma of the background count rate.
none
Summary:
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Four of seven labs have portal gate monitors. One has a walk-thru portal monitor.
Two of the labs that have portal gate monitors do not use them. One lab is having their gate monitor repaired.
Two of seven labs are developing or plan to use portal gate monitors or in-situ scrap/waste container monitor.
SLAC
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Fermilab
JLab
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SNS
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LBNL
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BNL
LANSCE
Argonne
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5. MARSSIM and MARSAME Considerations and Implementation
Process knowledge about potential activation from beam type, energy, loss, etc allows for zoning for different
levels of survey.
Discrete point measurements on surface grid instead of 100% full surface scan.
Number of samples for field or Lab analytic measurements is determined by process knowledge and/or
practicality.
We have not implemented MARSSIM and MARSAME at Fermilab.
Classification of areas requiring monitoring for release (impacted vs non-impacted) is analogous to
MARSAME method (PK, historical surveys, sentinel measurements, etc.).
All impacted material is surveyed (no distinction between Class 1, 2, 3). Survey detail on large objects driven
by process knowledge – uniform coverage of all surfaces with discreet points and scans, plus specific
assessments of any areas with potential for localized activity.
Number of analytic measurements determined by PK.
100% survey, some PK or (preferably) specific activation calculation needed. If no PK or calculation
available, gamma spec is standard approach.
We have limited process knowledge, but when sufficient knowledge available it is utilized during survey
planning.
For shield blocks, if there is process knowledge of block orientation within the shield wall, we scan the entire
inside face surface with 3x3 to find areas of elevated reading then make discrete point measurements at
highest elevated area and again at outside face. If insufficient process knowledge, then each face is scanned
and gamma spec performed on each face.
For materials other than shield blocks, full 100% scan is made.
Volumetric release at BNL has been performed with soils, asphalt and gravel. Volumetric release of solid
bulk items such as shielding has not occurred.
We evaluate the potential for item activation based on process knowledge.
In addition, we perform 100% survey on small items.
We use SLAC’s steps 2 and 3 otherwise.
If 100% surface area survey cannot be done; i.e. inaccessible surfaces, owner must dismantle item, or use a
process-knowledge statement form, co-signed by division director or designee.
Summary:
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None of the labs has implemented MARSAME or MARSSIM directly.
One of the labs does not use it.
Five of the labs have developed methods which are analogous to MARSAME/MARSSIM methods.
SLAC
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Fermilab
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JLab
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SNS
LBNL
BNL
LANSCE
Argonne
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6. Record Management
Facility release authorization records
RP survey records,
Survey of all components, but record identification of individual large components and identification of a
group of small and similar components (e.g., cables in a drum, small concrete blocks in a bin)
Photos for representative components or release bins/drums.
Were we to go into a moratorium release program these would be good things to do we would pick up from
the exemplary approved programs that would already be in place at SLAC and perhaps JLAB!
Primary record is survey/release form.
o All items leaving accelerator enclosure documented at the point of release
o Contains general description, specific ID if available
o Includes ID of individual to whom released
Release form augmented by contamination survey form and analytical reports if conducted
“Special” releases include photos and other data (usually done for extremely large items or materials that
have radiological history at non-JLab facility
Property sent offsite requires “authorization for shipment” form requiring user to certify no hazardous
materials.
Estimates of waste/scrap release reported in ASER.
Survey records in Websurvey
Health Physicist evaluation (if needed) is appended to Websurvey report
RPG survey records
Radiological release tag (not always required).
Certificate of burial for suspension items released for burial at landfill
Photos used, but not mandated by procedure and left up to preference of RCT performing survey.
Some surveys (e.g. those performed in support of RWP program) are tracked and pdf of signed survey in
RADAR. Others are tracked in traditional survey logbook.
Survey of small items for unconditional release recorded on item survey release log.
Volumetric release documented on volumetric release permit. http://intranetdev.bnl.gov/rcd/RCD
LANSCE RP surveys are documented.
We do not take pictures of items.
same as SLAC
Summary:
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For all labs, all surveys are documented. The survey document is the primary record.
Four labs have noted a release permit/authorization/form.
One lab keeps record of all surveys on a database.
Three labs also use photographs in survey forms.
SLAC
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7. Technical Basis
Process knowledge about isotope production and yields at electron accelerators, FLUKA generic calculations,
benchmark measurements and published radioactivity measurements.
Surface maximum concept allows for surface measurement.
Proxy isotope concept allows for measurements of easy-to-measure isotopes (long-half-life, high-energy, and
high-intensity beta-gamma isotopes versus hard-to-measure isotopes e.g., H-3 and Fe-55).
Detection limits evaluated.
We use process knowledge about radionuclide production, CASIM and MARS calculations, etc. We
understand fully that if we were seek approval for release we would have to tighten up our documentation of
these matters.
PK of nuclide production, likelihood of activation or contamination. Published/shared data from other
accelerators/labs.
Surrogate nuclides (proxy) for hard to detect isotopes.
Release criteria set at “indistinguishable from background” (IFB). Where quantitative activity determinations
are made, MDAs are required to be small fraction of ANSI SLs. Any detected activity (regardless of level)
disqualifies item from free release.
Benchmark measurements to evaluate sensitivity of field techniques. Confirmed by modeling.
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Volume: Benchmarking shows field sensitivity generally < 1/3 of ANSI.
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Surface: Any activity detected by field instrument assumed to be > 1000 dpm cm2 (i.e. IFB applied to GM
survey). Analytical methods used for hard to detect nuclides.
No detectable activity and (if available) calculated value less than surface contamination levels if the item was
all surface.
Measured activation less than Lc.
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Fermilab
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JLab
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SNS
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LBNL
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BNL
LANSCE
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Volume:
o Maximum MDA ~ 2 pCi/g (152Eu, 154Eu, 60Co), calculated from sampling and analysis.
o MDAs ≤ 1/10 of the ANSI N13.12 Screening Levels (SLs).
o ∑i (MDAi / SLi)  1
o Other sample MDAs established and approved by DOE in 1998 and vary depending on sample matrix.
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Surface:
o Maximum Scan MDC <3750 dpm/100 cm2 calculated assuming 6% instrument efficiency and
following MARSSIM, Rev. process for calculating MDC.
o MDC ≤ DOE O5400.5 Authorized Limits (ALs).
o ∑i (MDAi / ALi)  1
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Argonne
Process knowledge about the isotope production and yields at Bevatron. Published results of modeling
(Moeller, Donahue 1994).
Current NaI process to release Bevatron blocks was developed and verified through sampling and analysis.
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In work—we plan on developing MCNPX models for different accelerator/beam delivery areas of interest
using typical linac beam spill losses and Cinder calculations for isotopic analysis.
These calculations will be used to identify components and locations with a very low probability of becoming
activated.
We have used the proxy isotope concept (based on MCNPX) for tritium evaluation with the 1L tungsten
target contaminated water system.
Techniques 1, 2, and 4 have been employed on case-by-case basis
Summary:
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Process knowledge of isotope production is used at all labs.
Three labs noted using Monte Carlo methods.
Three labs noted using a proxy isotope concept.
SLAC
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Fermilab
JLab
SNS
BNL
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LANSCE
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Argonne
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8a. Site Impacts of Metal Hold
For PEP-II rings, BaBar detector, and currently HOLD metals, about 225,000 cuft materials (over 71,000 sqft
of area).
Process knowledge alternative to assist in the metals moratorium.
http://www.cadops.bnl.gov/AGS/Accel/SND/OPM/Ch09/09-05-14.PDF
1) Cost estimate in progress for removal of HRS spectrometer from Area C in FY12 (~500 tons of potentially
recyclable metal, 40 tons of non-activated lead).
2) Projects in conceptual phase such as MaRie and proton interrogation could involve hundreds to thousands
of tons of metals.
3) LANSCE Risk Mitigation project (work begins FY11) likely to involve a few to several tons of potentially
recyclable metals.
4) Area A cleanout (completed) left ~40 tons of “clean” lead currently in storage.
have not been estimated
SLAC
Fermilab
JLab
SNS
BNL
LANSCE
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Argonne
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8b. Estimated Impact for Option of Landfill Disposal
Total cost of shipping, labor, and landfill burial: $11M
$4M to bury and $3M lost revenue
1) Landfill disposal of steel: TBD. LLW disposal of steel: $178K. Macroencapsulation of lead at Clive:
$480K. (does not include labor, shipping)
2) TBD
3) TBD
4) Macroencapsulation of lead at Clive: $480K.
have not been estimated