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Subtask 1.5 Review of Draft Permit Consultant will review the draft permit provided by SJRWMD prior to final issuance, on behalf of the County. Consultant will provide written comments to the County and SJRWMD (if needed) for incorporation into the final permit. Task 2.0 MEETING WITH SJRWMD Consultant will perform the required groundwater modeling for inclusion in initial permit application submittal to SJRWMD. Modeling will be performed using the Southeast -Central (SEC) MODFLOW model that has been developed and calibrated by SJRWMD. SJRWMD is continuing to improve the calibration of the surficial aquifer system by more refined inclusion of the surface water network in the model area using the MODFLOW RIVER package. The Consultant will use the most recent version of the model available at the time when modeling begins. This model covers all of Indian River and St. Lucie Counties, along with portions of Brevard, Highlands, Okeechobee, Osceola and Polk Counties. Consistent with all of the other regional models developed by SJRWMD, the model was calibrated to 1995 conditions, which is a baseline year in which there was abundant water use and hydrological data available to calibrate the model. The model includes a representation of the surficial aquifer, the Intermediate Confining Unit (Hawthorn Group), the UFA and Lower Floridan Aquifer. Calibration of the model will be verified to ensure that the difference between measured groundwater elevations and model computed groundwater elevations (residuals) are within acceptable range and that there is no spatial bias in these differences. The verified model will be used to perform up to five modeling simulations (one 1995 baseline pumping scenario and four proposed County pumping scenarios) to determine the optimum pumping rates that will maximize the withdrawal from North County wellfield, as agreed upon by the County and the Consultant. These five simulations will use different combinations of North County wellfield and South County wellfield withdrawals along with other permitted users within the model extent withdrawing at the permitted annual average allocation. Model simulations will be used to determine the effects, if any, from the pumpage of the County's wellfield(s) based on the following resources evaluation criteria: • No interference with other existing legal uses; • Cannot induce saline water intrusion; • Cannot create or contribute to pollution of the water resources; • Cannot adversely affect existing offsite land uses; • Cannot produce impacts to wetlands; and • No lowering minimum flow and levels for designated water bodies. Consultant will produce maps showing the anticipated cone of depression for each wellfield pumping scenario and contours of incremental and cumulative groundwater level drawdown due to pumping. These maps will be used in the evaluation of potential impacts to the resource evaluation criteria above. A technical memorandum describing the model that was used, results of model verification, a description of the simulations performed, the results of the modeling and impact evaluation including figures and tables will be submitted to the County for review and comment. The Consultant will review and incorporate County comments and finalize the groundwater modeling memorandum. This final technical memorandum will be used to support the application to modify the County's CUP modification for increased operational flexibility. cSmith A-3 jj1703_Ltr with Exhibits.doc