title: Concentration and size distribution of particles in abstracted groundwater.
abstract: Particle number concentrations have been counted and particle size distributions calculated in groundwater derived by abstraction wells. Both concentration and size distribution are governed by the discharge rate: the higher this rate the higher the concentration and the higher the proportion of larger particles. However, the particle concentration in groundwater derived from abstraction wells, with high groundwater flow velocities, is much lower than in groundwater from monitor wells, with minimal flow velocities. This inconsistency points to exhaustion of the particle supply in the aquifer around wells due to groundwater abstraction for many years. The particle size distribution can be described with the help of a power law or Pareto distribution. Comparing the measured particle size distribution with the Pareto distribution shows that particles with a diameter >7 microm are under-represented. As the particle size distribution is dependent on the flow velocity, so is the value of the "Pareto" slope beta.
authors.affiliation: KWR Watercycle Research Institute (formerly Kiwa Water Research), P.O. Box 1072, 3430 BB Nieuwegein, the Netherlands. Kees.van.Beek@kwrwater.nl
authors.forename: C G E M
authors.initials: CG
authors.lastname: van Beek
authors.forename: A H
authors.initials: AH
authors.lastname: de Zwart
authors.forename: M
authors.initials: M
authors.lastname: Balemans
authors.forename: J W
authors.initials: JW
authors.lastname: Kooiman
authors.forename: C
authors.initials: C
authors.lastname: van Rosmalen
authors.forename: H
authors.initials: H
authors.lastname: Timmer
authors.forename: J
authors.initials: J
authors.lastname: Vandersluys
authors.forename: P J
authors.initials: PJ
authors.lastname: Stuyfzand
mesh_terms: D008956:Models, Chemical; D009426:Netherlands; D010316:Particle Size; D012987:Soil; D014881:Water Supply / Q000032:analysis*
chemical_list: D012987:Soil