TY - JOUR

T1 - Application of Groundwater Thresholds for Trace Elements on Percolation Water

T2 - A Case Study on Percolation Water from Northern German Lowlands

AU - Godbersen, L.

AU - Duijnisveld, W. H.M.

AU - Utermann, J.

AU - Gäbler, H. E.

AU - Kuhnt, G.

AU - Böttcher, J.

N1 - Copyright: Copyright 2013 Elsevier B.V., All rights reserved.

PY - 2012/7/1

Y1 - 2012/7/1

N2 - The German insignifi cance thresholds (GFS) for groundwater, derived with an added risk approach, will soon be adopted as trigger values for percolation water entering groundwater. Th e physicochemical properties of the vadose zone diff er considerably from those of groundwater, which may lead to diffi culties in the applicability of groundwater-derived GFS to percolation water. To test the applicability of the GFS to percolation water regarding the concentration level and the fi eld-scale variability, 46 sites in Northern Germany were sampled, including arable land, grassland, and forest, situated on three spatially dominant parent materials: sand, glacial loam, and loess. Concentrations of As, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, Sb, Sn, V, Zn, and F were analyzed in percolation water from the transition between the unsaturated to the saturated zone. We compared median and 90th percentile values of the background concentrations with the GFS. In more than 10% of all samples, background concentrations of Cd, Co, Ni, V, or Zn exceeded the GFS. We evaluated the applicability of the GFS on fi eld-scale medians of background concentrations taking fi eld-scale interquartile distance and the bootstrap percentile confi dence interval of the fi eld scale median of trace element background concentrations into consideration. Statements about exceedance or nonexceedance of GFS values could only be made with acceptable statistical uncertainty (α ≤ 0.1) when operational median concentrations were about one third higher or lower than the corresponding GFS.

AB - The German insignifi cance thresholds (GFS) for groundwater, derived with an added risk approach, will soon be adopted as trigger values for percolation water entering groundwater. Th e physicochemical properties of the vadose zone diff er considerably from those of groundwater, which may lead to diffi culties in the applicability of groundwater-derived GFS to percolation water. To test the applicability of the GFS to percolation water regarding the concentration level and the fi eld-scale variability, 46 sites in Northern Germany were sampled, including arable land, grassland, and forest, situated on three spatially dominant parent materials: sand, glacial loam, and loess. Concentrations of As, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, Sb, Sn, V, Zn, and F were analyzed in percolation water from the transition between the unsaturated to the saturated zone. We compared median and 90th percentile values of the background concentrations with the GFS. In more than 10% of all samples, background concentrations of Cd, Co, Ni, V, or Zn exceeded the GFS. We evaluated the applicability of the GFS on fi eld-scale medians of background concentrations taking fi eld-scale interquartile distance and the bootstrap percentile confi dence interval of the fi eld scale median of trace element background concentrations into consideration. Statements about exceedance or nonexceedance of GFS values could only be made with acceptable statistical uncertainty (α ≤ 0.1) when operational median concentrations were about one third higher or lower than the corresponding GFS.

UR - http://www.scopus.com/inward/record.url?scp=84864510523&partnerID=8YFLogxK

U2 - 10.2134/jeq2011.0218

DO - 10.2134/jeq2011.0218

M3 - Article

C2 - 22751069

AN - SCOPUS:84864510523

VL - 41

SP - 1253

EP - 1262

JO - Journal of Environmental Quality

JF - Journal of Environmental Quality

SN - 0047-2425

IS - 4

ER -