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Soil Vapor Probe Sampling It is proposed that the newly-installed sub-slab soil vapor probes and soil vapor probes (SS-1, SS-2, SV-3 and SV-4) and existing soil vapor probes (SV-1 and SV-2) be purged and sampled. The newly-installed probes will be allowed to equilibrate for a minimum of 48 hours prior to purging and sampling. Prior to purging and sampling a given vapor probe, shut-in testing will be conducted on the purging/sampling apparatus, and the purging/sampling apparatus adjusted as necessary. Upon completion of shut-in testing, a plastic shroud will be placed over the probe and sample collection equipment. For leak detection, a cloth rag saturated with isopropanol (rubbing alcohol) will be placed in the shroud directly adjacent to the soil vapor probe and sampling equipment. Each soil vapor probe will be purged of three purge volumes of vapor with either a Summa purge cannister, or a SKC PCXR4 or equivalent purge/sample pump in accordance with the Advisory. A purge volume is equal to the internal volume of the soil vapor probe and the volume of the filter pack of the probe. Following probe purging, soil vapor samples will be collected in 1-liter Summa canisters equipped with 200 mUmin flow controllers. Each Summa canister will be labeled with the probe number and time and date of sample collection. The Summa cannisters will be delivered to the laboratory using chain of custody procedures and protocols. Collected soil vapor probe samples will be analyzed for total purgeable petroleum hydrocarbons (TPPH) and VOCs in accordance with EPA Method No. TO-15, and for fixed gases including oxygen in accordance with ASTM D1946. The soil vapor sample laboratory analysis will be conducted by a State-certified hazardous waste testing laboratory. VAPOR EXTRACTION FEASIBILITY TESTING FREY proposes to conduct one vapor extraction test (VET) using existing vapor extraction well VW-1 to evaluate the effectiveness of vapor extraction at reducing the concentrations of petroleum hydrocarbons in vadose zone soils. Vapor extraction testing of well VE1, which is screened from 5 to 10 feet bgs (Appendix C) will allow for assessing the feasibility of extracting soil vapor from upper vadose zone soils between approximately 5 and 10 feet bgs near former soil boring B-1, where the highest benzene concentrations in soil were historically detected. The vapor extraction testing will assess parameters required to design a vapor extraction system. FREY Environmental, Inc. 7 1092-01