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d 14 November 2014 AGE Project No . 07-1529 Page 2 of 6 Based on CVRWQCB requirements , two additional injection wells screened from 100 to 120 feet bsg are proposed for installation , adjacent to the locations of wells MW-9 and MW- 13. A site plan illustrating the locations of the proposed wells is included as Figure 2 . A detailed work plan for installation of the wells is provided below. CVRWQCB Comment 2: In the NOI, you propose using MW-2, MW-8, and MW- 18 as transition zone wells and MW-6 and MW- 10 as compliance zone wells. The compliance zone wells are over 100 feet from the treatment zone and would require monitoring for a very long time before a groundwater response could be observed at this location. Compliance zone wells should be located at a reasonable distance downgradient of the treatment zone to ensure breakdown products generated or mobilized from the ISCO reaction do not exceed water quality objectives and groundwater limitations. Considering the location of the proposed compliance zone wells and site lithology consisting of silty clay, groundwater constituents from the ISCO reaction potentially may not be observed in the compliance wells for over 10 years. Central Valley Water Board staff is concerned that the proposed compliance zone wells are too far from the Site to provide useful data in determining if water quality objectives and groundwater limitations are exceeded. Central Valley Water Board staff recommends installation new transition zone wells and utilizing the proposed transition zone wells as compliance zone wells. In addition, please provide an estimated groundwater velocity to support the proposed transition and compliance zone well locations. Based on Water Board comments above , AGE recommends installation of two transition zone wells east of the locations of the installed injection wells and treatment zone at the site . The proposed locations of one shallow and one deep transition well are illustrated on Figure 2 . A work plan detailing the proposed well installations is included below . Furthermore , based on Water Board requirements , AGE has provided groundwater velocity (seepage velocity) calculations for both the shallow and deep groundwater monitoring zones . For the shallow monitoring zone , AGE calculated the seepage velocity at approximately 0 . 0016 feet per day (ft/day) . For the deep zone , the seepage velocity was calculated at 0 . 17 ft/day . Assumptions and calculations for seepage velocity for both shallow and deep monitoring zones is included in Appendix B . Updates have been also been completed to the MRP , which is included in Appendix C . CVRWQCB Comment 3: A contingency plan must be included in the NOI that ensures compliance with Section E (Groundwater Limitations) of the General Order. The contingency plan must include constituent concentration trigger levels in compliance zone wells that will require implementation of the contingency plan. Advanced GeoEnvironmen[al, Ine.