6C(2) Proposal for Supplemental Phase II Assessment

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accessible areas in close proximity include alleyways to the immediate west and south of the subject site (side gradient and up gradient). Using Geoprobe methodologies (small track mounted hydraulically driven sampling probe) soil samples from a total of five locations. One soil boring (GP -5) is proposed for the common alleyway to the west of the subject site. Two additional soil borings are proposed for the residential lot to the southwest of the site. One of the borings (GP -6) would be located within the front yard, along Indiana Avenue; the second (GP -7) being located in the rear yard, along the eastern property boundary of the lot. The fourth boring (GP -8) will be established within the east /west alleyway, near the intersection of Kendall Avenue. The final boring (GP -9) is proposed to be located within the public park area to the east of the subject site, across Kendall Avenue. For each of the Geoprobe boring locations, discrete soil samples will be collected at 4- foot intervals throughout the soil profile to a depth of 20 feet below ground surface, or until saturated soil conditions are encountered. Each soil sample interval will be screened for the presence of volatile organics by placing a portion of the soil sample into a plastic bag, allowing time for equilibration, and insertion of a photo ionization detector (PID) probe to observe a reading of "total VOCs" in parts per million (ppm). All data associated with the field screening of VOCs will be recorded for future reference (Soil Boring Logs). In addition, a portion of each discrete sampling interval will also be collected for submittal to the laboratory. PES proposes to submit two soil samples from each of the five boring locations based on the PID field screening results and /or other indications of the presence of potential contamination (visual or olfactory). In the event that field screening with a PID, visual or olfactory observations do not indicate the presence of contamination; the two depth intervals immediately above the soil /groundwater interface will be submitted for laboratory analysis. Each of the soil samples selected for laboratory analysis will be analyzed for the presence of Volatile Organic Compounds (VOCs). PES will utilize IDEM guidance Terra -Core Methods to collect soil samples from each discrete sampling interval for the analysis of VOCs. All soil samples will be labeled, packed on ice and forwarded to the laboratory under chain -of- custody procedures. Temporary Geoprobe Well Installation for Groundwater Sampling PES proposes to convert each of the five Geoprobe soil borings to temporary wells with insertion of a Geoprobe groundwater sampling device, which allows for the extension of a stainless steel slotted screen for collection of a groundwater sample from the point at which the saturated or water - bearing zone is encountered. For this proposal, PES has assumed that the water - bearing zone will be encountered within 20 -feet of land surface. Once installed, each temporary well would be purged until such time as the water discharge becomes relatively free of solids or until at least three gallons of water have been removed. PES proposes that groundwater from each of the temporary wells be analyzed for VOCs. Each groundwater sample will be appropriately labeled, packed on ice, and forwarded to the laboratory (priority overnight delivery) under chain -of- custody procedures. PES will plug the boreholes /wells with bentonite once soil and groundwater sampling activities have been completed. Reporting Upon receipt of the laboratory analyses, data will be reviewed and tabularized. Comparison of the data for each respective chemical constituent will be made to the