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Mr. Chris Dressel
<br />July 25, 2016
<br />581074.300.0001
<br />Page 3
<br />Task 1 b Interim Quarterly Groundwater Monitoring
<br />Groundwater samples will be collected from monitoring wells MW-1S (shallow screened depth), MW-II
<br />(intermediate screened depth), MW-1 D (deep screened depth), PMW-1 1, MW-135, MW-145, MW-165,
<br />MW-171, MW-17D, HMW-19, MW-20S/D, MW-21 S/D, MW-22S/D, MW-23S/D, MW-24, MW-25S/D,
<br />MW-26S/D, MW-27S/D, MW-28S/D, MW-29S/D, and MW-30S/D and submitted to the laboratory for
<br />VOC analysis using U.S. EPA Method 8260. This cost estimate also includes costs for laboratory analyses
<br />on samples collected from replacement monitoring wells installed as part of Task 2 below. As noted
<br />above, Hull will endeavor to reduce as much as possible the number of samples to be analyzed to save the
<br />City costs wherever possible.
<br />Duplicate samples will be collected at randomly selected monitoring well locations. Field/equipment
<br />blanks will also be collected and submitted along with a trip blank for analysis as part of QA/QC of field
<br />procedures. Purge and decontamination waters will be collected and stored in U.S. DOT -approved 55-
<br />gallon drums. Costs to remove, transport, and dispose of four 55-gallon drums of containerized
<br />groundwater (which is presumed to be non -hazardous) are included in this task.
<br />For the proposed sampling events, Hull will continue to deploy passive diffusion bag (PDB) samplers in all
<br />monitoring wells, which are a significantly more cost-effective .sampling methodology that has been
<br />accepted by IDEM. PDBs are polyethylene bags filled with onalyte-free water that are hung in monitoring
<br />wells for a minimum of 14 days. Field personnel return to the monitoring well, retrieve the sampler, and
<br />collect the sample by filling sampling vials in the same manner as traditional methods. Significant savings
<br />are realized by reducing mobilization, purging., and sampling time; by minimizing the volume (and thereby
<br />cost and environmental footprint) of field materials such as low -flow tubing; and by eliminating most
<br />equipment rental costs. Laboratory analytical subcontractor costs for this Task include the cost of replacing
<br />PDBs during each semi-annual sampling event at each well, and for Level IV QA/QC reporting by the
<br />laboratory.
<br />Task 2 Replace Decommissioned Monitoring Wells
<br />IDEM has indicated that certain monitoring wells that have been decommissioned to accommodate
<br />redevelopment of the parcels sold to Indiana -Michigan Power and ABC Supply must be replaced. This
<br />cost estimate assumes replacement of two nested shallow and intermediate monitoring well clusters and
<br />one nested shallow, intermediate, and deep monitoring well cluster — for a total of seven monitoring wells
<br />at three separate locations — will be required. However, because the monitoring well network is already
<br />relatively extensive, Hull will attempt to negotiate fewer monitoring wells than the proposed seven.
<br />Hull will work with the drilling subcontractor, the property owners, and the appropriate City and St. Joseph
<br />County authorities to arrange for access for the work and to clear utilities and to prepare appropriate
<br />permits for drilling in the right-of-way, if necessary. Drill cuttings and sample purge and decontamination
<br />water will be containerized and placed at a location designated by the City.
<br />Following agreement between the City, IDEM, and Hull on the final quantity and locations of the monitoring
<br />wells, the nested monitoring wells will be installed on- and/or off -Site at the agreed upon locations. Soil
<br />borings associated with the proposed monitoring wells will be drilled using 4.25-in., inside -diameter
<br />hollow -stem augers and continuously sampled using 24-in. split -spoon samplers to the appropriate depths
<br />(currently proposed to be 25 feet for shallow wells, 40 feet for intermediate wells, and 55 feet for the
<br />sole deep well at one clustered location). The final locations of the monitoring wells may be modified
<br />based on field observations. Although the deepest boring at each location will be continuously sampled,
<br />soil samples are not proposed to be submitted for laboratory analyses as part of the monitoring well
<br />installation. Regardless, as standard procedure, the Hull field personnel will screen soils with a
<br />photoionization detector (PID) during sail boring logging to evaluate for the presence of soil contamination.
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