title: A method for conducting simultaneous convergent tracer tests in multilayered aquifers.
abstract: Forced gradient tracer tests between two boreholes can be used to study contaminant transport processes at the small field scale or investigate the transport properties of an aquifer. Full depth tests, in which tracer samples are collected just from the discharge of the abstraction borehole, often give rise to breakthrough curves with multiple peaks that are usually attributed to different flow paths through the aquifer that can rarely be identified from the test results alone. Tests in selected levels of the aquifer, such as those between packer-isolated sections of the boreholes, are time consuming, expensive; and the identification of major transport pathways is not guaranteed. We present a method for simultaneously conducting multiple tracer tests covering the full depth of the boreholes, in which tracer sampling and monitoring is carried out by a novel multilevel sampling system allowing high frequency and cumulative sampling options. The method is applied to a tracer test using fluorescein conducted in the multilayered sandstone aquifer beneath the city of Birmingham, UK, producing six well-defined tracer breakthrough curves.
authors.affiliation: Water Sciences (Hydrogeology), School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
authors.forename: Richard B
authors.initials: RB
authors.lastname: Greswell
authors.forename: Véronique
authors.initials: V
authors.lastname: Durand
authors.forename: Maria F
authors.initials: MF
authors.lastname: Aller
authors.forename: Michael S
authors.initials: MS
authors.lastname: Riley
authors.forename: John H
authors.initials: JH
authors.lastname: Tellam
mesh_terms: D001435:Bacteriophages; D004739:England; D004784:Environmental Monitoring / Q000379:methods*; D019793:Fluorescein / Q000032:analysis; D060587:Groundwater / Q000737:chemistry*; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D014874:Water Pollutants, Chemical; D019793:Fluorescein