MODFLOW-2005 groundwater flow models and MT3DMS solute transport models were developed to represent conditions in the vicinity of a bioremediation experiment conducted in fractured rocks underlying the former Naval Air Warfare Center, West Trenton, New Jersey. The groundwater flow models include transient simulations of water-level changes during six field aquifer tests and steady-state simulations of hydraulic head at the site. The solute transport models include simulations of bromide tracer transport and of injection conditions during the bioremediation experiment. ZONEBUDGET and MODPATH were used for postprocessing analyses of flow modeling output. UCODE_2014 was used to calibrate the flow models and to conduct uncertainty analyses.

MODFLOW-2005 groundwater flow models were developed to simulate 47 pumping tests conducted for a hydraulic tomography experiment in fractured rocks underlying the former Naval Air Warfare Center, West Trenton, New Jersey. These flow models simulate the change in water level during the pumping tests, which range from about 45 to 60 minutes in duration. MODFLOW-2005 models were also developed to simulate groundwater flow in different directions across the hydraulic conductivity field estimated by the hydraulic tomography, and MODPATH simulations were conducted to identify flow paths in these simulations. This USGS data release contains all of the input and output files for the simulations described in the associated journal article (https://doi.org/10.1111/gwat.12915)

MODFLOW-2005 groundwater flow models were developed to simulate 47 pumping tests conducted for a hydraulic tomography experiment in fractured rocks underlying the former Naval Air Warfare Center, West Trenton, New Jersey. These flow models simulate the change in water level during the pumping tests, which range from about 45 to 60 minutes in duration. MODFLOW-2005 models were also developed to simulate groundwater flow in different directions across the hydraulic conductivity field estimated by the hydraulic tomography, and MODPATH simulations were conducted to identify flow paths in these simulations. This USGS data release contains all of the input and output files for the simulations described in the associated journal article (https://doi.org/10.1111/gwat.12915)

The U.S. Geological Survey, in cooperation with the U.S. Department of the Navy, developed several 3-D groundwater flow models for used with MODFLOW-2005, MODFLOW-NWT, and SEAWAT model codes to evaluate variable-density groundwater flow and contaminant transport in Operable Unit 1 on Naval Base Kitsap in Keyport, Washington. Chlorinated volatile organic compounds (CVOCs) have migrated to groundwater beneath a former 9-acre landfill at Operable Unit 1 (OU-1). The three predominant ground-water contaminants are the chloroethene compounds trichloroethene (TCE), cis-1,2-dichloroethene (cis-DCE), and vinyl chloride (VC). A need for remedial action was identified because some of the contaminants present a potential risk to humans primarily through drinking contaminated groundwater or through ingesting seafood harvested from contaminated surface water. An ongoing effort with the U.S. Navy and U.S. Geological Survey (USGS) began in 1995 by evaluating the effectiveness of natural attenuation processes for removing and controlling the migration of CVOCs in ground water at OU-1. Additional collection of geochemical and contaminant concentration data demonstrated that biodegradation of CVOCs in shallow groundwater at OU-1 is substantial and prevents most of the mass of dissolved-phase CVOCs in groundwater beneath the landfill from discharging to surface water. However, dissolved-phase contaminant concentrations in the hundreds of milligrams per liter continue to persist in localized areas of OU-1. Data suggest that residual sources of chloroethenes in the form of non-aqueous phase liquid remain at the site, and that biodegradation is only partly effective at reducing the dissolved-phase contaminants that are generated from these sources. In 2018 an additional USGS effort was begun to simulate variable-density groundwater flow and contaminant transport in the vicinity of OU-1 using a revised hydrogeologic model of the site and a refined delineation of persistent contaminant sources. MODFLOW-2005 and MODFLOW-NWT model codes were used to calibrate a new model. Then groundwater flow and contaminant transport models were developed using SEAWAT-Version 4, a computer program based on MODFLOW and MT3DMS, to simulate three-dimensional variable-density groundwater flow coupled with multi-species solute transport. These models were used to simulate the direction and rate of groundwater flow near OU-1, estimate the CVOC mass in groundwater and the rate of mass loading, and assess possible remedial activities at OU-1. 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/sir20205066).

A groundwater-flow model was used to simulate zones of contribution to wells south of Naval Weapons Industrial Reserve Plant, Bethpage, New York. The model results will be used to demonstrate how the size and shape of zones of contribution may vary.

A three-dimensional groundwater flow model was developed to simulate the effects of withdrawals on the groundwater-flow systems of five aquifers in and around Ocean County, New Jersey—the unconfined Kirkwood-Cohansey aquifer system and Vincentown aquifer, and three confined aquifers--the Rio Grande water-bearing zone, the Atlantic City 800-foot sand, and the Piney Point aquifer. A transient model was used to simulate conditions that represent no groundwater withdrawals, 2000–2003 groundwater withdrawals, and maximum-allocation groundwater withdrawals. Particle-tracking analysis, using results from two steady-state simulations, determine flow paths and travel times to near-shore wells screened in the unconfined Kirkwood-Cohansey aquifer system, the Rio Grande water-bearing zone, and the Atlantic City 800-foot sand. Sources of water to wells in both unconfined and confined aquifers and travel times based on particle-tracking analysis are used to assess the susceptibility of selected wells to saltwater intrusion from bay or ocean water. 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/sir20165035).

A three-dimensional groundwater flow model was developed to simulate the effects of withdrawals on the groundwater-flow systems of five aquifers in and around Ocean County, New Jersey—the unconfined Kirkwood-Cohansey aquifer system and Vincentown aquifer, and three confined aquifers--the Rio Grande water-bearing zone, the Atlantic City 800-foot sand, and the Piney Point aquifer. A transient model was used to simulate conditions that represent no groundwater withdrawals, 2000–2003 groundwater withdrawals, and maximum-allocation groundwater withdrawals. Particle-tracking analysis, using results from two steady-state simulations, determine flow paths and travel times to near-shore wells screened in the unconfined Kirkwood-Cohansey aquifer system, the Rio Grande water-bearing zone, and the Atlantic City 800-foot sand. Sources of water to wells in both unconfined and confined aquifers and travel times based on particle-tracking analysis are used to assess the susceptibility of selected wells to saltwater intrusion from bay or ocean water. 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/sir20165035).

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).

The study of Whiting Field Naval Air Station, Milton Florida requires numerical modeling of the groundwater system to determine the fate of contaminants released at the air station in previous decades. The MODFLOW-NWT modeling code (Niswonger and others, 2011) was applied for this purpose with field data defining a number of inputs including aquifer properties and timeseries. Lithologic logs were used to define aquifer material types and estimated hydraulic conductivities were redistributed based on these logs. Net recharge (precipitation minus evapotranspiration) is the primary flow input to the model and stream leakage is the primary flow output. The resulting model simulation has a grid spacing of 100 feet with grid dimensions of 533 rows and 424 columns, with 7 vertical layers. In order to better represent the flow transporting surficial contaminants to the water table, the unsaturated zone flow (UZF) package (Niswonger and others, 2006) was implemented in MODFLOW-NWT to relate surficial recharge to water-table recharge. The simulation involved three warmup timesteps of 1000 days each followed by 17 daily timesteps representing the transient simulation of June 24-July 10, 2017. Simulation results were evaluated by comparing simulated water-table elevations and stream leakage with measured values. Output values of interest include groundwater flow vectors in horizontal plane view and along vertical transects in locations where contaminant transport could be occurring. Model-simulated velocity vectors were compared with a known benzene plume location to evaluate flow directions. At the northern part of the plume, the flow-vector magnitudes are small and the highest Benzene concentrations are seen in this relatively stagnant area. Higher flow-vector magnitudes further to the south and southeast move the plume towards a nearby creek. 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/sir20215124).

An existing three-dimensional model (MODFLOW-2000) by Fine, Petkewich, and Campbell (2017) (https://doi.org/10.3133/sir20175128) was used to evaluate 7 water-management scenarios and predict the effects on the groundwater flow and groundwater-level conditions in the Mount Pleasant, South Carolina area. This model was originally developed in 2007, by Petkewich and Campbell (https://pubs.er.usgs.gov/publication/sir20075126), then updated and recalibrated to conditions from 1900 to 2015. Results of six previous scenario simulations (scenarios 1-6) for the Mount Pleasant Water Works are published in a U.S. Geological Survey (USGS) Scientific Investigations Report (https://doi.org/10.3133/sir20175128). The archived model input and output files are available in a USGS data release (https://doi.org/10.5066/F7S181FC). Seven additional MODFLOW-2000 scenarios (numbered 7-13), using this updated and recalibrated model, were developed to evaluate different withdrawal strategies which are included in this data release: (7) Mount Pleasant Waterworks bringing online a new well (located at the old well 5 location) at 3.51 million gallons per day (Mgal/d) in 2025; (8) Maximizing withdrawals from Mount Pleasant Waterworks wells 2 and 5 (3.51 Mgal/d each) in 2020 and 2025, respectively; (9) Same as Scenario 7, but removing well 3 from production in 2025; (10) Same as Scenario 9, but removing well 4 from production in 2025 (11) Same as Scenario 7, but converting well 3 to an injection well in 2025 (12) Same as Scenario 11, but converting well 4 to an injection well in 2030; and (13) Same as scenario 8, but with two injection wells added (one in 2025 and one in 2035) to Mount Pleasant Waterworks well field. Nine alternate simulations for scenarios 11-13 (three MODFLOW and six MODPATH) were done to evaluate the effects of different porosity on the groundwater flow system, water levels, and the time-of-travel of particles from injection wells to the main water source. This USGS data release contains all the input and output files for the simulations described above and in the readme.txt file of this data release (https://doi.org/10.5066/P9GZEE4E).