MODFLOW-2000 and MODPATH4 used to simulate groundwater flow and contaminant transport in the Pohatcong Valley, Warren County, New Jersey
Description
The U. S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency,
developed a numerical ground-water-flow model, using MODFLOW-2000, to simulate
ground-water flow in the Pohatcong Valley including the area within the Pohatcong Valley
Ground Water Contamination Site. In 1978, the chlorinated solvents trichloroethene (TCE)
and tetrachloroethene (PCE) were detected in thePohatcong Valley in production wells in
Washington Borough and Washington Township, Warren County, New Jersey. Subsequent
investigation revealed that many domestic wells in Washington and Franklin Townships
also were contaminated, and in 1989 the Pohatcong Valley Ground Water Contamination
Site was added to the U.S. Environmental Protection Agency (USEPA) National Priority List.
A remedial investigation, by the USEPA and CH2M Hill with technical assistance from the
U.S. Geological Survey (USGS), was begun in 1999. The simulation of ground-water flow in
the Pohatcong Valley described here was conducted by the USGS in cooperation with the
USEPA. The ground-water-flow model, using MODFLOW-2000 and the particle–tracking
program MODPATH, estimated flow paths of groundwater from known sources of contamination
in Washington Borough and tested possible site contamination remediation alternatives. Five
ground-water remediation alternatives (GW2a, GW2b, GW3a, GW3b, and GW4b) were
simulated. In addition, a 10-year solute transport simulation was conducted, using the USGS
groundwater-transport process, to illustrate the potential for dispersion to increase the width of
the solute plume. This USGS data release contains all of the input and output files for the
simulations described in the associated model documentation report
(https://doi.org/10.3133/sir20065269).