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Ms. Ann Kolata 561070.400.0002 October 15, 2013 Page 5 This estimate includes costs to install one additional deep and shallow nested monitoring well location if needed based on the results of the soil sampling in Task 2 above (e.g., within the former Oliver foundry parcel). Soil borings associated with the proposed monitoring wells will be drilled using 4.25 -in., inside - diameter hollow - stem augers and continuously sampled using 24 -in. split -spoon samplers to the appropriate depth (i.e., either 30 feet bgs or 45 feet bgs). Similar to the locations of the direct -push sampling points, the final locations of the monitoring wells may be modified based on field observations. Although the deeper boring at each location will be continuously sampled, soil samples are not proposed to be submitted for laboratory analyses as part of the monitoring well installation. Monitoring wells will be constructed of Schedule 40 PVC slotted screens and risers. Once the targeted depth has been reached, the well column will be slowly lowered to the base of the borehole. A clean silica quartz sand filter pack will be placed around the screen and will extend no more than two feet above the top of the screen. Sodium bentonite chips or pellets will then be placed on top of the sand pack. Above the chips or pellets, a thick bentonite slurry will be pumped into the annular space using a tremie pipe to a depth of approximately three feet below ground surface. The remaining three feet will be filled with concrete to anchor a flush -mount manhole. Monitoring wells will be developed following installation to remove fines that may have entered the well screen or filter pack during installation. Well development activities will continue until pH, temperature, and conductivity have stabilized for three consecutive well volumes, or until five well volumes have been removed, whichever is greater. Development waters will be collected and stored in a DOT approved 55- gallon drum. Costs to remove, transport, and dispose of approximately 51 55- gallon drums of containerized groundwater and drill cuttings (which are presumed to be non - hazardous) are included in this task. Task 4 Conduct Quarterly Groundwater Monitoring Following the installation of new monitoring wells, a routine of quarterly groundwater sample collection from all monitoring wells is proposed. This will establish a baseline and, after several quarters, will begin to allow for seasonal trend analysis. After four to six quarters, a sufficient trend should be established to allow for an analysis of whether certain monitoring wells can be removed from the quarterly sampling routine, with IDEM concurrence. In the meantime, however, this estimate assumes that quarterly groundwater samples will be collected from all existing and newly - installed monitoring wells on- and off -Site (an estimated total of 51 monitoring wells) for 8 quarters. Groundwater samples will be collected from all newly installed monitoring wells and submitted to the laboratory for VOC analysis using U.S. EPA Method 8260. Duplicate samples will be collected at randomly selected monitoring well locations. Field /equipment blanks will also be collected and submitted along with a trip blank for analysis as part of QA /QC of field procedures. Purge and decontamination waters will be collected and stored in U.S. DOT - approved 55- gallon drums. Costs to remove, transport, and dispose of eight 55- gallon drums of containerized groundwater and drill cuttings (which are presumed to be non- hazardous) are included in this task. For the proposed sampling events, in lieu of traditional low -flow sampling methods that have been employed at the Site previously, Hull proposes to deploy passive diffusion bag (PDB) samplers in all monitoring wells, which are a significantly more cost- effective sampling methodology that has been accepted by IDEM. PDBs