Title
Modelling assessment of regional groundwater contamination due to historic smelter emissions of heavy metals
Author
van der Grift, B.
Griffioen, J.
TNO Bouw en Ondergrond
Publication year
2008
Abstract
Historic emissions from ore smelters typically cause regional soil contamination. We developed a modelling approach to assess the impact of such contamination on groundwater and surface water load, coupling unsaturated zone leaching modelling with 3D groundwater transport modelling. Both historic and predictive modelling were performed, using a mass balance approach for three different catchments in the vicinity of three smelters. The catchments differ in their hydrology and geochemistry. The historic modelling results indicate that leaching to groundwater is spatially very heterogeneous due to variation in soil characteristics, in particular soil pH. In the saturated zone, cadmium is becoming strongly retarded due to strong sorption at neutral pH, even though the reactivity of the sandy sediments is low. A comparison between two datasets (from 1990 to 2002) on shallow groundwater and modelled concentrations provided a useful verification on the level of statistics of "homogeneous areas" (areas with comparable land use, soil type and geohydrological situation) instead of comparison at individual locations. While at individual locations observations and the model varies up to two orders of magnitude, for homogeneous areas, medians and ranges of measured concentrations and the model results are similar. A sensitivity analysis on metal input loads, groundwater composition and sediment geochemistry reveals that the best available information scenario based on the median value of input parameters for the model predicts the range in observed concentrations very well. However, the model results are sensitive to the sediment contents of the reactive components (organic matter, clay minerals and iron oxides). Uncertainty in metal input loads and groundwater chemistry are of lesser importance. Predictive modelling reveals a remarkable difference in geochemical and hydrological controls on subsurface metal transport at catchment-scale. Whether the surface water load will peak within a few decades or continue to increase until after 2050 depends on the dominant land use functions in the areas, their hydrology and geochemical build-up. © 2007 Elsevier B.V. All rights reserved.
Subject
Geosciences
Catchment-scale
Groundwater flow
Metal transport
Modelling
Soil
Catchments
Groundwater pollution
Heavy metals
Mathematical models
Catchment-scale
Metal transport
Groundwater flow
cadmium
ground water
heavy metal
iron oxide
metal
organic matter
Catchments
Groundwater flow
Groundwater pollution
Heavy metals
Mathematical models
assessment method
comparative study
concentration (composition)
emission
groundwater flow
groundwater pollution
heavy metal
hydrological modeling
leaching
smelting
spatial variation
three-dimensional modeling
transport process
vadose zone
article
comparative study
concentration (parameters)
geochemistry
hydrology
leaching
pH measurement
priority journal
sandy soil
sediment
sensitivity analysis
smelter
soil analysis
statistics
time series analysis
transport kinetics
water contamination
water loading
water transport
Computer Simulation
Fresh Water
Industrial Waste
Metals, Heavy
Netherlands
Soil
Water Movements
Water Pollutants, Chemical
To reference this document use:
http://resolver.tudelft.nl/uuid:31529c64-064e-4f8e-9c14-34eda37ff0ea
TNO identifier
240657
ISSN
0169-7722
Source
Journal of Contaminant Hydrology, 96 (1-4), 48-68
Document type
article