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J r. Three simulations were performed at pumping rates of 6, 1, and 0 75 gpm At pumping rates of 6 and 1 gpm, model predictions of head exceeded the bottom of the aquifer (i e , bottom of the wells) Figure 5 indicates a prediction of head distributions under steady-state conditions at a pumping rate of 0 75 gpm The model predicts a radius of influence exceeding the estimated area of dissolved petroleum hydrocarbons in groundwater indicated in the Aegis FRP Figure 6 indicates predictions of groundwater velocities and direction at steady-state conditions at a pumping rate of 0 75 gpm The figure indicates groundwater velocities and flow directions are affected approximately 100 feet off site in the downgradient direction, and confirm the predicted radius of influence exceeds the estimated area of dissolved petroleum hydrocarbons in groundwater indicated in the Aegis FRP Figures 7, 8, and 9 indicate particle tracking predictions at the specified pumping rate after 500 days, 2,500 days, and steady-state conditions, respectively A total of 65 particles were placed in the domain at varying distances from the pumping well The retardation rate of the particles was set at 1 due to the limited amount of collected data The predictions, therefore, represent approximate tracking times for particles of water Travel times and distances for hydrocarbon particles may be much longer Figure 7 predicts that within 500 days, water from the estimated extent of dissolved hydrocarbons is captured Figure 8 predicts that after 2,500 days most of the particles released along the site boundary have been captured by the well Figure 9 indicates particle tracking under steady-state conditions and, thus, predicts the maximum achievable capture zone under the assumed conditions The figure predicts particles will be captured in the downgradient direction between 75 and 100 feet from the boundary of the site In summary, the model predicts • Sustained yield of Well MW-1 B may not exceed approximately 0 75 gpm unless the saturated thickness of the aquifer is greater than the measurements made in October 1991 • Pumping 0 75 gpm from well MW-1 under the assumed conditions will create a cone of depression, radius of influence, and capture zone in excess of the estimated extent of dissolved hydrocarbons • Under the assumed conditions, it would take in excess of 500 days to capture the estimated extent of dissolved petroleum hydrocarbons in groundwater Therefore, with the current specified pumping regime, it is feasible to control the estimated extent of dissolved hydrocarbons, but it may not be feasible to capture and remove the estimated extent of dissolved hydrocarbons due to time and costs considerations