Laserfiche WebLink
ATTACHMENT F <br /> DRILLING AND MONITORING WELL INSTALLATION <br /> PROCEDURES <br /> Drilling was conducted using 10-inch-diameter continuous-flight, hollow-stem auger drilling <br /> equipment. Soil samples for logging were obtained from auger-return materials. The soil was <br /> logged by an EMCON Associates geologist according the Unifier! Soil Classification System <br /> and standard geological techniques. <br /> A headspace analysis was conducted using a hand-held photoionization detector (PID) <br /> calibrated to an isobutylene standard. The soil was placed in a plastic Ziploc`n' bag, sealed, <br /> and placed in a warm atmosphere. After approximately 15 minutes, which is generally <br /> sufficient for volatiles to escape from the soil, the PID probe was inserted into the plastic <br /> bag. The total volatile hydrocarbons present were detected by the PID and reported in <br /> parts per million. <br /> • The drill cuttings for the borings were stockpiled with soilenerated from remediation <br /> anon <br /> system trenching and covered with plastic. Following completion of the soil borings, a drill <br /> cuttings composite soil sample was collected for chemical analysis to determine the <br /> appropriate soil disposal method. The samples were collected by driving brass rings into <br /> the cuttings. The rings were sealed at both ends with Teflon'h' tape and plastic end caps and <br /> placed on ice pending delivery to a state-certified laboratory for analysis. The soil was <br /> transported to Forward, Inc., Landfill in Stockton, California. <br /> A sand pack of #3 sand was placed in the annular space between the polyvinyl chloride <br /> casing and the borehole wall. The sand pack was added to the borehole through the hollow <br /> stem of the augers to provide a uniform sand pack around the casing and to stabilize the <br /> borehole. The sand pack was placed above the screen, and a seal consisting of bentonite <br /> pellets was placed above the top of the sand. <br /> A 4 percent bentonite cement grout was placed above the bentonite seal to within 3.0 feet <br /> of the ground surface. The wells were connected to the remediation system piping, and <br /> gravel was placed from approximately 1.0 to 3.0 feet below ground surface. A traffic-rated <br /> vault box set in concrete was installed over the well, and a watertight locking cap was <br /> installed over the top of each well casing. <br /> SAGA:TJ Z%2520\25201000.1PS-94V1b:1 F-I Rev-0,4/14/95 <br />