WORK PLANS - Laserfiche WebLink

Home Browse Search

GERAGHTY & MILLER. INC. 2 site-specific health and safety plan will also be prepared for use by Geraghty & Miller employees during the drilling and soil sampling activities. Prior to drilling, Geraghty & Miller will obtain the necessary drilling permits from the appropriate agencies. Geraghty & Miller will submit a site-specific work plan and health and safety plan along with the permit application,.as required by San Joaquin County Public Health Services. TASK 2: DRILLING AND SOIL SAMPLING ACTIVITIES This task assumes that two additional groundwater monitoring wells will be installed at the subject property and that groundwater will be encountered at a depth of approximately 50 feet. The borings for the groundwater monitor wells will be drilled using 8-inch diameter, hollow-stem augers. The borings will be terminated approximately 10 feet below top of groundwater or 5 feet into a low permeability layer, whichever occurs first. All drilling equipment that enters the borings will be steam-cleaned before drilling each boring. Soil samples will be collected at approximately 5-foot depth intervals, using a modified California split-spoon sampler equipped with brass liners that is advanced into the undisturbed soil beyond the tip of the augers. The split-spoon sampler will be washed in a solution of phosphate-free detergent and potable water, and triple-rinsed in potable water prior to each use. For health and safety reasons, field measurements of volatile organic compounds will be performed in the breathing zone using a photoionization detector(PID) (TE Instruments 580B Model OVM meter or equivalent). Soil samples for laboratory analysi"s will be retained in the brass liners, sealed with Teflon" tape and plastic end caps, placed on ice, and transported to a State-approved laboratory, along with appropriate chain-of-custody documentation. The.soil samples will be submitted to the laboratory on a standard turnaround time. Upon completion, the borings will be converted into groundwater monitor wells by installing 2-inch diameter Schedule 40 PVC casing. The screen portion of the casing, consisting of 0.01-inch slots, will extend from the bottom of the boring to approximately 5 feet above the top of groundwater. A sand pack, using RMC Lonestar sand #1/20 or equivalent grade, will be placed in the annular space to a depth approximately 1 foot above the top of the screened portion of the casing. One foot of bentonite seal will be placed above the sand pack, and the remainder of the annular space will be backfilled with a cement/bentonite slurry. The actual well completion may vary, based on the hydrogeologic conditions encountered during the drilling activities. Each wellhead will be secured belowgrade using a lockable watertight cap and completed at the surface with a traffic-rated monitor well cover. The location of each well (geodetic northings and eastings) and the top-of-casing elevation relative to mean sea level will not be surveyed. Project No. RCO291.001 r