HR: 1340h
AN: H23B-1303    [Abstracts]
TI: Environmental Risk Propagation From Contaminated Land Through Groundwater
AU: * Persson, K
EM: klas.persson@natgeo.su.se
AF: Department of Physical Geography & Quaternary Geology, Stockholm University, Stockholm, 106 91, Sweden
AU: Destouni, G
EM: georgia.destouni@natgeo.su.se
AF: Department of Physical Geography & Quaternary Geology, Stockholm University, Stockholm, 106 91, Sweden
AB: We present and use a limiting-scenario methodology for investigating the spatial development of environmental risk, defined as the probability of groundwater contaminant concentrations downstream of accidentally or industrially contaminated land to exceed given environmental target (maximum allowed) concentration levels. We use a stochastic advective travel time-attenuation approach to model contaminant transport for different extreme scenarios of contaminant release dynamics and downstream aquifer heterogeneity structures. For both short- pulse and long-term continuous contaminant releases, the environmental risk decline with transport distance is relatively insensitive to the degree of aquifer heterogeneity (hydraulic conductivity variance). It is further also practically insensitive to aquifer heterogeneity structure (isotropy/anisotropy, spatial correlation length) for short- pulse contaminant releases, and to contaminant release dynamics (short-pulse or long-term continuous release) for relatively isotropic aquifer heterogeneity structures. Above a certain ratio between mean attenuation rate and mean groundwater flow velocity, the transport distance at which environmental risk falls below, e.g., the 1% level is insensitive to the relation between environmental target and source input concentration for all investigated extreme contaminant release and aquifer heterogeneity scenarios. It is important to identify such risk development patterns and similarities for different extreme scenarios because they indicate similar risk behaviour, and may thus considerably simplify risk assessment, also for intermediate, more realistic and complex contaminant release and aquifer heterogeneity cases.
DE: 1829 Groundwater hydrology
DE: 1831 Groundwater quality
DE: 1847 Modeling
DE: 1869 Stochastic hydrology
DE: 1873 Uncertainty assessment (3275)
SC: Hydrology [H]
MN: 2007 Fall Meeting