title: A passive-discrete water sampler for monitoring seepage.
abstract: This paper presents the design of the passive-discrete water sampler (PDWS) which has been developed to facilitate investigations of flow partitioning in fractured rocks. The PDWS continuously isolates seeping water into discrete samples while monitoring the seepage rate. The PDWS was used in a flow and transport experiment that investigated fracture-matrix interactions. During the experiment, a mix of conservative tracers with significantly different diffusion coefficients (lithium bromide [LiBr] and pentafluorobenzoic acid [PFBA]) was introduced along a fault located in fractured tuffs, and water seeping through the lower end of the fault was collected by the PDWS and analyzed for tracer concentrations. Preliminary results from this investigation show that samples of effluent captured by the PDWS effectively retained temporal changes in the chemical signature, while providing seepage rates.
authors.affiliation: Earth Sciences Division, Lawrence Berkeley National Laboratory, Mail Stop 14-116, 1 Cyclotron Road, Berkeley, CA 94720, USA. r_salve@lbl.gov
authors.forename: Rohit
authors.initials: R
authors.lastname: Salve
mesh_terms: D001565:Benzoates / Q000032:analysis; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods*; D019015:Geologic Sediments; D018021:Lithium Chloride / Q000032:analysis; D014872:Water Movements; D014875:Water Pollutants, Radioactive / Q000032:analysis*; D005464:Fluorobenzenes; D005466:Fluorocarbons
chemical_list: D001565:Benzoates; D018021:Lithium Chloride; D014875:Water Pollutants, Radioactive; C090819:pentafluorobenzoic acid; D005464:Fluorobenzenes; D005466:Fluorocarbons