ARCHIVED REPORTS_XR0009515 - Laserfiche WebLink

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3. Underground utilities will be identified and located prior to commencing operations. 4. The County EHD will be notified a minimum of 48 hours prior to beginning work. PROGRAM; 1. Move in properly licensed auger rig for the boring and installation of the three (3) monitoring wells shown on PLATE VIII. 2. Using clean 10-1/4" OD hollow-stem augers, advance three (3) soil borings to approximately 55 feet below ground level at the approximate locations shown on PLATE VIII. Groundwater is estimated to be at 45 feet (PLATE IV), therefore each boring will penetrate ten (10) feet into the water sand. The augers and sampler will be cleaned between borings to avoid the possibility of cross-contamination. 3. Soil samples will be taken at 5 foot intervals from ten (10) feet to bottom using a California Modified Spitspoon Sampler or wireline operated continuous coring equipment designed to hold standard brass tubes for proper preservation of the cores. 4. One (1) sample tube from each cored interval will be briefly described, the ends promptly covered with foil or teflon tape, sealed with plastic caps, and securely wrapped with duct tape. The samples will be labeled and preserved on ice pending transport by proper chain of custody to a State Certified laboratory for analysis of BTEX, TPH-gasoline, and total lead using methods and detection limits agreeable to the County EHD. S. Drill cuttings, rinsate, and unpreserved core material will be placed in properly marked and sealed drums and stored on site pending the results of the laboratory analysis. 6. Each boring will be converted into a groundwater monitoring well by-installing 4" OD, screw-type, internal flush, blank and slotted, schedule 40 PVC casing, gravel packed, sealed and grouted as shown on the enclosed schematic, EXHIBIT I The top of the perforations will extend a minimum of 5' above the water table, and 10' below. 7. Each well will be equipped with a preformed surface vault, thoroughly cemented in place, and a suitable heavy duty locking traffic cover. The casing will extend far enough up into the vault to allow placement of an expandable cap and lock assembly. The top of each casing will be matched on the north side to facilitate measurements. Each well cover will be clearly identified for future reference. 8. Within 18 to 24 hours after completion, each well will be developed by swabbing with a hard rubber disc or suitable device for at least 15 minutes, or as directed by the County EHD personnel. Fluids removed will be placed in properly labeled drums and securely sealed for storage on location. Disposal of the contents will 4