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Ms. Ann Kolata 561070.400.0002 October 15, 2013 Page b are polyethylene bogs filled with analyte -free water that are hung in monitoring wells for approximately 14 days. Field personnel return to the monitoring well, retrieve the sampler, and collect the sample by filling sampling vials in the same manner as traditional methods. Significant savings are realized by reducing mobilization, purging, and sampling time; by minimizing the volume (and thereby cost and environmental footprint) of field materials such as low -flow tubing; and by eliminating most equipment rental costs. Laboratory analytical subcontractor costs for this Task include the cost of PDBs for each well, and for Level IV QA /QC reporting by the laboratory. This estimate assumes that the City and Hull will succeed in gaining IDEM approval to cease sampling groundwater for lead and arsenic, which should be acceptable given the proposed restriction of groundwater use as discussed in Task 5 below. A brief draft letter report documenting the results of each quarterly sampling event will be prepared and submitted to the Client for review. Once the draft letter report is reviewed by the Client and finalized by Hull, a copy will be submitted to the IDEM VRP. Task 5 Evaluate GW Remedies, Restrict GW Use. and Amend the RWP Once the extent of downgradient groundwater impacts, the current status of groundwater impacts on -Site, and the potential off -Site [i.e., south and southwest (upgradient)] sources that may be contributing to groundwater entering the Site's southern boundary are better understood by the activities to be completed in steps 2, 3, and 4 above, the prior remedy (i.e., EOSTM) that was pilot tested — and shown to be effective — will be re- evaluated for additional applications. At present, we presume that it will remain the preferred option, but as the groundwater in -situ treatment technology market has evolved in the last 3 -4 years, we will commit to evaluating similar chemistries that may offer a cost and /or effectiveness advantage. As we have discussed previously, Hull recommends that the City effectively render incomplete the groundwater ingestion exposure pathway at and in the vicinity of the Site by ensuring that St. Joseph County Code 52, Section 52.042 is enforced, which prohibits the installation of wells for potable use where a municipal water source is available, and Section 52.043 is implemented for the vicinity of the Site, which governs the establishment of an Administrative Control Area (ACA). The language of Section 52.043, whereby an ACA is established, contains additional relatively far- reaching yet flexible provisions to further restrict exposure to groundwater when a threat to human health may be present. Hull and the City's outside counsel have already engaged the St. Joseph County Health Department to begin the process of establishing an ACA, and will continue to pursue this effort. We are confident that once the ACA is established, the groundwater ingestion exposure pathway will officially be rendered incomplete, thereby eliminating the need to sample groundwater on- and off -Site for lead and arsenic concentrations. The results of the additional soil sampling in Task 1 above, the evaluation of the proposed groundwater remedy, the extent to which a future remedy is necessary based on the additional groundwater delineation and monitoring, and the progress of establishing the ACA will be summarized in an amendment to the December 2011 RWP. A draft of the forthcoming amended RWP will be provided to the City and its outside counsel prior to finalization and submittal to IDEM. SCHEDULE Hull can begin coordinating soil and groundwater sampling immediately, subject to your approval of this proposal. Assuming our drilling subcontractor remains reasonably available, we anticipate all drilling and sampling activities will be completed by the end of November 2013, and that the Amended RWP can be