title: Development and calibration of a portable radon sampling system for groundwater 222Rn activity concentration measurements.
abstract: The assembling of a system for field sampling and activity concentration measurement of radon dissolved in groundwater is described. Special attention is given in presenting the calibration procedure to obtain the radon activity concentration in groundwater from the raw counting rate registered in a portable scintillation detector and in establishing the precision of the activity concentration measurements. A field procedure was established and the system tested during one year of monthly observations of (222)Rn activity concentration in groundwater drawn from two wells drilled on metamorphic rocks exposed at Eastern São Paulo State, Brazil. The observed mean (222)Rn activity concentrations are 374Bq/dm(3) in one well and about 1275Bq/dm(3) in the other one. In both wells the (222)Rn activity concentrations showed a seasonal variation similar to variations previously reported in the literature for the same region.
authors.affiliation: Departamento de Geofísica, Instituto de Astronomia, Geofísica e Ciências Atmosféricas da Universidade de São Paulo, Rua do Matão, 1226, Cidade Universitária, Butantã, 05508-090 São Paulo, SP, Brazil.
authors.forename: Fabio de Oliveira
authors.initials: Fde O
authors.lastname: Lucas
authors.forename: Igor José Chaves
authors.initials: IJ
authors.lastname: de Oliveira
authors.forename: Fernando Brenha
authors.initials: FB
authors.lastname: Ribeiro
mesh_terms: D002138:Calibration; D019015:Geologic Sediments / Q000737:chemistry*; D011834:Radiation Monitoring / Q000295:instrumentation* / Q000379:methods; D011886:Radon / Q000032:analysis*; D014867:Water / Q000737:chemistry*; D014875:Water Pollutants, Radioactive / Q000032:analysis*
chemical_list: D014875:Water Pollutants, Radioactive; D014867:Water; D011886:Radon