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Mr. Himanshu H . Mehta, P . E . 30 September 2011 Page 5 will be performed at a frequency of semi- annually ( in conjunction with current semi- annual groundwater sampling at the site) , for a minimum of one sampling event following the performance of injection activities, and laboratory analyzed for UIC parameters . UIC parameters include total recoverable petroleum hydrocarbons (TRPH), polysorbate 80 surfactant (by method SM5540-1)) , sodium , chloride and total dissolved solids ( TDS) . UIC parameter analysis will be performed on groundwater samples from three monitoring wells, including : ( i) GR-MW3013 in the former source area; (ii) GR-MW02D located adjacent to and down-gradient of biobarrier transect 1 ; and ( iii) GR- MW28D located adjacent to and down- gradient of biobarrier transect 3 . Additional sampling will not be conducted for the referenced parameters if, sample results from the semi-annual event following the injection activities meet UIC criteria . It is anticipated that semi- annual CVOC and total organic carbon (TOC ) sampling currently performed (and contracted) at the site is adequate for performance monitoring of the source area and biobarriers . This sampling will continue to include semi-annual sampling for TOC in one former source area monitoring well ( GR- MW3013 ), a monitoring well downgradient of biobarrier transect 1 (GR-MW021)), and a monitoring well downgradient of biobarrier transect 3 (GR-MW281)) . TOC concentrations will be evaluated as an indicator of the presence of electron donor. Field parameters (pH, dissolved oxygen, and oxidation-reduction potential) will continue to be recorded during semi- annual groundwater sampling activities and will be utilized to evaluate whether the aquifer continues to be conducive to reductive dechlorination . It has been assumed that the UIC and performance monitoring will be conducted within the currently authorized semi-annual groundwater monitoring budget and therefore no additional budget is included for these activities herein. However, the scope is discussed above to inform the County about the additional analytical costs that should be expected because the analytical costs are directly billed to IRC SWDD . SCHEDULE FDEP has requested that the County begin implementation of the required activities by 21 October 2011 . Geosyntec will initiate these activities within two weeks of receipt of notice to proceed from the County . The final field schedule will be based on subcontractor availability . We anticipate that the field activities will tentatively be conducted in November and/or December 2011 . A description of the well installation and dosing activities will be included in future semi -annual groundwater monitoring report( s) . BUDGET ESTIMATE A budget estimate for the scope of work outlined in Phases 1 through 4 of this proposal is summarized in the following table, and a detailed budget estimate is provided as Exhibit 1 . The budget estimate presented in this proposal is based on Geosyntec ' s understanding of the project XR11055\XR11072 f' nIlf11"we. rs `civrltists innovators