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technical FACT SHELI

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BUILDING A SCIENTIFIC FOUNDATION FOR SOUND ENVIRONMENTAL DECISIONS
EPA's rapid radiochemical methods expedite analytical
turnaround time for selected radionuclides while providing
quantitative results that meet measurement quality objectives.
Methods are applicable to samples where contamination is from
either known or unknown origins. This fact sheet is intended for
radioanalytical laboratory personnel, decision makers within the
incident command structure, additional reoccupancy decision
makers (e.g., state and local public health), and other field
environmental response personnel.
Method Summary: This method is a sample dissolution and pretreatment technique used prior to other separation and analysis
methods. Refractory radioisotope thermoelectric generator (RTG) particles are collected on a 0.45 pm filter using vacuum, RTG
activity remaining in the aqueous filtrate is preconcentrated using calcium phosphate precipitation. The filtered solids fraction
and the filtrate fraction are processed separately by fusing with sodium hydroxide/sodium peroxide prior to subsequent chemical
separation and alpha spectrometric analysis. Plutonium (Pu) is separated from the fusion matrix using a lanthanum/calcium
fluoride matrix removal step in preparation for separation and analysis using the Rapid Radiochemical Method forPu-238 and
Pu-239/240 in Building Materials for Environmental Remediation Following Radiological Incidents.
Time to Process: 10.25-13.25 hr
Includes fusion, radiochemical processing, and counting
Compare to traditional method: N/A: no validated
methods available for this special matrix
Method Application
This fusion method is applicable to the total dissolution of
refractory RTG materials via rapid, rigorous, and effective
dissolution of refractory radionuclide particles present in water
matrices. Application of this method should be validated by the
laboratorv usina the protocols provided in Method Validation
Guide for Qualifyinci Methods Used bv Radioloqical
Laboratories Particioatina in Incident Response Activities, or
the protocols published by a recognized standards organization
for method validation.
Measurement Quality Objectives
Required method uncertainty: 2.1 pCi/L
Analytical action level (AAL): 16.3 pCi/L
Required relative uncertainty: 13% above AAL
Minimum detectable concentration (MDC): 0,23 pCi/L
Sample quantity: 1 L
Count time: 360 minutes; 240 minutes for MDC
Equipment and Supplies
Balance: top loading or analytical, +0.01 g readability or better
| Cartridge reservoirs: 10 or 20 mL syringe style with locking
device, or equivalent | Centrifuge: able to accommodate 225
mL tubes | Centrifuge tubes: 50 mL and 225 mL tubes |
Crucibles: 250 mL zirconium with lids | Filters: 0.45 pm
membrane | Hot plates: adjustable temperature | Laboratory
supplies: 1000 mL beaker; 100 pL, 200 pL, 500 pL, 1 mL
pipettes and plastic tips; 1—10 mL electronic/adjustable pipette;
tongs; tweezers | Muffle furnace capable of reaching at least
700° C | Reusable vacuum filter units to hold 47 mm filters
with 500 mL receivers or equivalent filter apparatus | Vacuum
system: box; pump or laboratory system | Vortex stirrer
Sample Preservation
None listed in method
Waste Generated
Waste disposal information is provided in the plutonium
chemical separation method
Method Access:
https://www.epa.qov/sites/production/files/2015-
06/documents/rtq dissolution bv fusion rev 0 402r 1400
3.pdf
Contacts
Program: Kathy Hall	Technical: John Griggs
513-379-5260	334-270-3450
hall.kathy@epa.gov	griggs.john@epa.gov
EPA/600/S-17/059
March 2017
Rapid Radiochemical Method for
Fusion of Radioisotope
Thermoelectric Generator (RTG)
Materials in Water Prior to Plutonium
(Pu) Analyses
U.S. Environmental Protection Agency
Office of Research and Development, Homeland Security Research Program

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