title: PRex: An Experiment to Investigate Detection of Near-field Particulate Deposition from a Simulated Underground Nuclear Weapons Test Vent.
abstract: A radioactive particulate release experiment to produce a near-field ground deposition representative of small-scale venting from an underground nuclear test was conducted to gather data in support of treaty capability development activities. For this experiment, a CO2-driven "air cannon" was used to inject (140)La, a radioisotope of lanthanum with 1.7-d half-life and strong gamma-ray emissions, into the lowest levels of the atmosphere at ambient temperatures. Witness plates and air samplers were laid out in an irregular grid covering the area where the plume was anticipated to deposit based on climatological wind records. This experiment was performed at the Nevada National Security Site, where existing infrastructure, radiological procedures, and support personnel facilitated planning and execution of the work. A vehicle-mounted NaI(Tl) spectrometer and a polyvinyl toluene-based backpack instrument were used to survey the deposited plume. Hand-held instruments, including NaI(Tl) and lanthanum bromide scintillators and high purity germanium spectrometers, were used to take in situ measurements. Additionally, three soil sampling techniques were investigated and compared. The relative sensitivity and utility of sampling and survey methods are discussed in the context of on-site inspection.
authors.affiliation: *Pacific Northwest National Laboratory, P.O. Box 999, MSIN: J4-65, Richland, WA 99352; †University of Florida, Materials Science and Engineering, P.O. Box 116400, Gainesville, FL, 32611; ‡National Security Technologies LLC, Las Vegas, NV, 89193; §Oregon State University, Nuclear Science and Engineering, 3451 SW Jefferson Way, Corvallis, OR, 97331.
authors.forename: Martin E
authors.initials: ME
authors.lastname: Keillor
authors.forename: Leah M
authors.initials: LM
authors.lastname: Arrigo
authors.forename: James E
authors.initials: JE
authors.lastname: Baciak
authors.forename: Veraun
authors.initials: V
authors.lastname: Chipman
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Detwiler
authors.forename: Dudley F
authors.initials: DF
authors.lastname: Emer
authors.forename: Warnick J
authors.initials: WJ
authors.lastname: Kernan
authors.forename: Randy R
authors.initials: RR
authors.lastname: Kirkham
authors.forename: Matthew R
authors.initials: MR
authors.lastname: MacDougall
authors.forename: Brian D
authors.initials: BD
authors.lastname: Milbrath
authors.forename: Jeremy P
authors.initials: JP
authors.lastname: Rishel
authors.forename: Allen
authors.initials: A
authors.lastname: Seifert
authors.forename: Carolyn E
authors.initials: CE
authors.lastname: Seifert
authors.forename: John E
authors.initials: JE
authors.lastname: Smart
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D003198:Computer Simulation; D006207:Half-Life; D006801:Humans; D007811:Lanthanum / Q000032:analysis*; D054043:Nuclear Weapons; D052638:Particulate Matter / Q000032:analysis*; D011834:Radiation Monitoring; D011847:Radioactive Fallout / Q000032:analysis*; D012107:Research Design
chemical_list: D000396:Air Pollutants, Radioactive; D052638:Particulate Matter; D011847:Radioactive Fallout; D007811:Lanthanum