Laserfiche WebLink
Drilling and Sampling Proceduresiiy, <br /> F� <br /> Soil Sampling <br /> Soil borings were permitted through the San Joaquin County Public Health Services, Environmental . <br /> Health Division. Locations were cleared by Underground Service Alert (USA)prior to drilling. <br /> A truck-mounted drill rig equipped with 8-inch diameter hollow stem augers was used to complete <br /> the borings. Soil samples were collected using a split-spoon sampler. Soils encountered during <br /> drilling were classified by Harza staff by visual examination in the field in accordance with the <br /> Unified Soil Classification System. Boreholes were backfilled with a bentonite-cement grout to the <br /> surface. <br /> Soil samples for chemical analysis were collected in 2-inch diameter, 6-inch long brass liners. <br /> Sample liners were sealed with Teflon tape and plastic end-caps, labeled, and immediately placed <br /> in iced storage for transport to a state-certified analytical laboratory. A chain-of-custody form was <br /> initiated in the field and accompanied the samples. <br /> Select soil samples were collected using a hand auger. Samples collected from hand auger borings <br /> were collected as bulk grab samples and placed in glass jars sealed with Teflon-lined lids. <br /> Sampling equipment was steam cleaned,or washed with a laboratory grade detergent and rinsed with <br /> distilled water before use and between samples to minimize the potential for cross-contamination. <br /> Water Sampling <br /> Prior to sampling, ground water monitoring wells were purged of at least three casing volumes of <br /> water until the physical parameters pH,EC,and temperature stabilized. Purging was accomplished <br /> using a Teflon bailer,a peristaltic pump with Teflon tubing,or a Grundfos pump with PVC tubing. <br /> Purged water was contained in drums on site. <br /> Ground water samples were collected following purging using a Teflon bailer. The bailer was <br /> lowered into the monitoring well or open borehole,and allowed to fill with water. The sample was <br /> then decanted into laboratory-supplied containers, labeled,and placed in iced storage for transport <br /> to a state-certified analytical laboratory with accompanying chain-of-custody forms. The surface <br /> water sample was collected using a dipper fitted with a linear polyethylene(LPE)cup. The cup was <br /> 11-21-95 A-1 <br />