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16 June 2016 <br />AGE Project No. 95-0167 <br />Page 3 of 5 <br />Percent oxygen (fixed gas) in accordance with analytical method ASTM D 1946- <br />90; and <br />Tracer compound isopropyl alcohol in accordance with EPA Method TO-15. <br />Laboratory reports for soil-vapor analyses (lowest possible detection limits), testing <br />methods, laboratory quality assurance/quality control (QA/QC) reports, and sample <br />chain-of-custody documentation will be presented in a report with the findings and <br />recommendations. Electronic deliverable format (EDF) files of the laboratory analytical <br />results will be submitted to the State of California GeoTracker database. <br />3.0. PROCEDURES <br />All field procedures will be overseen by an AGE representative under the supervision of <br />a California Professional Geologist. Procedures for advancing soil borings, collection and <br />analysis of soil-vapor samples, equipment decontamination and sample handling are <br />presented below. <br />3.1. SOIL-VAPOR WELL INSTALLATION <br />AGE proposes to advance a total of two (2) pilot soil borings to 5.5 feet bsg for installation <br />of depth discrete soil-vapor wells to evaluate the potential threat of vapor intrusion to the <br />site building. Proposed soil borings will be advanced using a 3-inch diameter hand auger. <br />For installation of soil-vapor wells, 1/4-inch diameter, 2-inch long polyethylene soil vapor <br />implants and eight feet of 'A-inch Teflon® tubing will be lowered to the base of the borings; <br />three feet of tubing will remain outside the boreholes for vapor sample collection. <br />However, before installing the vapor implant and tubing, approximately six inches of #2/12 <br />sand will be placed at the bottom of the boreholes for the vapor implants to be placed on. <br />Once the six inches of sand, tubing and vapor implants are in place, the filter pack of <br />#2/12 sand will continue to be added from the bottom of the boreholes to approximately <br />six inches above the top of the vapor implants. Following placement of the filter pack, <br />approximately 10 inches of dry granulated bentonite will be placed atop the filter packs. <br />The remaining annular space will be filled to the ground surface with a cement grout. The <br />grout mixture will consist of Type I/II Portland neat cement with approximately 3-5% <br />bentonite content. A flush mounted well box will then be installed over the wells. <br />Approximately, 3 feet of extra tubing will be run above ground for soil-vapor sample <br />collection. A well construction diagram illustrating the proposed design is included as <br />Figure 3. <br />Once soil-vapor wells are installed, a minimum of 48 hours equalization time will be <br />observed prior to sampling the wells. <br />Advanced GeoEnvironmental Inc.