Example: Akacievej
Example: Setup and application of models for a field site (Akacievej, Hedehusene)
First, several models were compared for a contaminated site in Denmark, where a plume of dissolved PCE has migrated through a fractured limestone aquifer. Numerical modeling was integrated in the planning of field tests and in the update of the conceptual model. Field data includes information on spill history, distribution of the contaminant (multilevel sampling), geology and hydrogeology. To describe the geology and fracture system, data from borehole logs, packer tests, optical televiewers and cores was combined with an analysis of local heterogeneities and data from analogue sites. A pumping and tracer test with depth-specific contaminant sampling was conducted at the site to determine flow and transport parameters of the fractures and matrix and to quantify the contaminant distribution in the aquifer. Different models were used for the planning and interpretation of the pumping and tracer test. This is described in the following report:
To reduce the numerical effort and to simulate the plume propagation on a larger scale, a coupled 2D plume-scale and 3D source-zone model was developed. The 3D model resolves flow and transport in the source zone. Therefore, an initial contaminant distribution in the source zone was implemented, which is based on depth-specific measurements of PCE. The source-zone model is then used to compute the contaminant input fluxes for the 2D model, which starts at the downstream end of the source zone model.
The following report (in Danish) shows the setup and application of this coupled 3D source-zone and 2D plume-scale model, which supported the re-evaluation of the remediation system at the Akacievej site: