technical FACT SHEET
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 uses two chromatographic extraction resins to isolate and purify plutonium (Pu) by removing interfering
radionuclides as well as other components of the matrix in order to prepare the Pu fraction for counting by alpha spectrometry. The method
uses vacuum-assisted flow to improve the speed of the separations. Prior to using the extraction resins, a water sample is filtered as
necessary to remove any insoluble portions, equilibrated with 242Pu tracer, and concentrated by either evaporation or calcium phosphate
[Ca3(P04)2] coprecipitation. The sample test source is prepared by microprecipitation with neodym(lll)-fluoride. Standard laboratory protocol
for the use of an alpha spectrometer should be used when the sample is ready for counting.
Time to Process: 7.5 hr
Includes radiochemical processing and counting
Compare to traditional method (ASTM D3084-05): 14—27 hr
Method Application
The method is specific for soluble 238Pu and 23s®»Pu in drinking
water and other aqueous samples. Application of this method
should be validated by the laboratory using the protocols
provided in Method Validation Guide for Qualifvina Methods
Used bv Radioloaical Laboratories Participatina in Incident
Response Activities, or the protocols published bv a
recognized standards organization for method validation.
Measurement Quality Objectives
Required method uncertainty: 1.9 pCi/L
Analytical action level (AAL): 15 pCi/L
Required relative uncertainty: 13% above AAL
Minimum detectable concentration: 1.5 pCi/L
Sample quantity: ~ 200mL
Count time: At least 1 hr
Equipment and Supplies
Alpha spectrometer calibrated for range of - 3.5-10 MeV
| Analytical balance: 10~4 g readability or better |
Cartridge reservoirs: 10 or 20 mL syringe style with
locking device, or equivalent | Centrifuge and 250 mL
flasks | Filter apparatus with 25 mm diameter polysulfone
filtration chimney, stem support, and stainless steel support
or a single-use (disposable) filter funnel/filter combination |
Filters: 0.45 pm membrane; 25 mm polypropylene with 0.1
pm pore size or equivalent | Laboratory supplies: 250 mL
and 500 mL plastic/glass ware; 10 mL plastic culture tubes
with caps; 100 pL pipettes and plastic tips; pH paper;
stainless steel planchets or other sample mounts able to
hold the 25 mm filter; tweezers | Vacuum system: box;
pump or laboratory system; white inner tips; yellow outer
tips | Vortex mixer
Sample Preservation
Samples should be collected in 1 L plastic containers
Analysis within 3 days of sampling: No preservation required
Holding time >3 days: Adjust pH to <2 with concentrated
nitric acid
Waste Generated per Sample
~ 90 mL acidic waste
~ 1 mL hydrofluoric acid
~ 8 mL ethanol
~ 100-1000 mL pH neutral decanted solution if Ca3(PO,})2
coprecipitation performed
2 resin cartridges
Isotopes of americium, uranium, neptunium, and thorium if
present in the original sample
Contacts
Proaram: Kathv Hall Technical: John Griaas
513-379-5260 334-270-3450
hall.kathy@epa.gov griggs.john@epa.gov
Method Access:
https://www.epa.aov/sites/production/files/2015-
06/documents/DU-238-239 in water rev 0 1 eDa 402-r-
10-001 b.odf
www.epa.gov/research
Rapid Radiochemical Method
Plutonium-238 (238Pu) and 239Pu in
Water Samples
U.S. Environmental Protection Agency
Office of Research and Development, Homeland Security Research Program
EPA/600/S-17/058
March 2017

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