Laserfiche WebLink
AdvancedGeo <br />Environmental <br />08 February 2018 <br />AGE Project No. 17-4116 <br />Page 3 of 4 <br />Following soil-vapor point installations, a minimum of one-hour stabilization period will be <br />observed prior to sample collection at each of the vapor point locations. A one-liter <br />Summa canister and a 6-liter purge canister will be connected together with a dedicated <br />and serialized sampling inlet manifold. The sampling inlet manifold will consist of an <br />air/vapor-tight valve; a particulate filter; a calibrated flow restrictor calibrated to 200 <br />milliliters per minute (ml/min), a stainless steel tee-fitting, two vacuum gauges at either <br />end of the controller and connections for both purge and sampling canisters (manifold <br />assembly). The manifold assembly will be attached to the 'A-inch Teflon® tubing from the <br />vapor sampling locations. The purge canister will be attached to the end of the sampling <br />manifold while the sample canisters will be attached to the tee-fitting between the tubing <br />and purge container. <br />Leak tests will be performed on each soil-vapor sampling assembly by attaching and <br />securing the sample and purge canisters to the manifold and opening the valve on the <br />purge canister and the manifold. The leak test will be performed for approximately 3 to 5 <br />minutes on each assembly. <br />Upon achieving a successful leak test, the purge canister valve will be opened for a <br />calculated period of time to allow for three volumes of air to be purged. The purge canister <br />vacuum gauge will be monitored to ensure a proper decrease of vacuum ensuring flow <br />and purging. The purge volume will be determined by calculating the internal volume of <br />the tubing and open borehole area. <br />Upon achieving the targeted purge volume, the purge canister valve will be closed and <br />the sample canister valve will be opened. The initial pressure and time will be recorded. <br />Upon reaching at least -5 in Hg or less, the sample canister valve will be closed and final <br />pressure and time recorded. The sampling port on the sampling canister will be capped <br />with a brass end-cap. <br />All soil-vapor samples will be labeled with sample ID, project name, date, time, and <br />samplers' initials. The samples will be logged on a chain-of-custody form, and placed into <br />dry containers. Subsequently, all collected soil-vapor samples will be delivered to a <br />California Department of Public Health (CDPH)-certified analytical laboratory for analysis. <br />EQUIPMENT DECONTAMINATION/WASTE MANAGEMENT <br />Prior to use, all non-disposable sampling tools used for sample collection will be <br />thoroughly rinsed with clean water after being washed with a solution of Alconox. <br />BORING ABANDONMENT <br />All soil borings will be permanently sealed to prevent vertical migration of potential <br />contaminants. Soil borings shall be abandoned by backfilling with cement grout from the