Numerical simulation of the groundwater-flow system of the Kitsap Peninsula, west-central Washington

Abstract

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Multifactor analysis of specific storage estimates and implications for transient groundwater modelling

“…Seven of the reviewed models used spatially variable S S using pilot point parameterization with a spatial interpolation method (kriging) for specific layers (Bilge 2012;Frans and Olsen 2016;Khan et al 2002;Liu et al 2014;OGIA 2019;Pawel and Matthew 2018;Vermeulen and Kelder 2020). Pawel and Matthew (2018) modelled the Heretaunga aquifer for groundwater resource assessment with spatially variable S S that was calibrated for each of the two layers.…”

Variable-density groundwater flow and contaminant transport, Operable Unit 1, Naval Base Kitsap, Keyport, Washington

“…CVOC mass-degradation rates and fluxes to surface water were calculated by Dinicola and others (2002) and Dinicola (2006) from contaminant concentrations and water-level contour maps. A three-dimensional characterization of hydraulic head and groundwater flow rates in the 575 square mile (mi 2 ) area surrounding the Keyport Peninsula is available from a steady-state, numerical groundwaterflow model of the Kitsap Peninsula developed by Frans and Olsen (2016).…”

“…The area includes Virginia Point, a residential area with domestic wells located 0.6 mi northwest of OU-1 across Dogfish Bay. Study area boundaries were delineated to coincide with the model grid of the Kitsap Peninsula used by Frans and Olsen (2016), so simulated groundwater levels from their model could be used to set boundary conditions for the Keyport models. Variable-density groundwater flow and contaminant transport was simulated within a smaller 1.3 mi 2 transport domain within the larger 5.9 mi 2 study area that is centered on OU-1 and surrounds the Keyport Peninsula ( fig.…”

“…Model domain boundaries coincide with the model grid of the 3D Kitsap groundwater-flow model of Frans and Olsen (2016), but they do not correspond to natural hydrologic boundaries. Hydraulic heads and flow rates computed by the Kitsap model were used to set head and flow boundaries in the Keyport model in two model layers below the top of the Clover Park Aquitard (Unit 7: QC1) with the FHB package.…”

“…Keyport model boundaries coincide with the model grid of the 3D Kitsap groundwater-flow model of Frans and Olsen (2016), and hydraulic heads and flow rates computed by the Kitsap model were used to set head and flow boundaries in the Keyport model. Hydraulic heads were specified at model boundaries in model layers 13 and 15 representing the permeable interbeds within the Clover Park Aquitard (Unit 8; QC1pi) and the sea-level aquifer (Unit 10; QA1), respectively, and vertical flows exchanged between the sea-level aquifer and deeper model layers in the Kitsap model were specified in model layer 15.…”