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Reconnaissance Groundwater Sampling Procedures <br /> 10 <br /> This procedure is used when reconnaissance groundwater sampling without permanent wells is <br /> desired Either HydroPunch® or temporarily cased open boreholes may be used <br /> 1 . Reconnaissance groundwater sample, handling, and storage will follow guidance documents of <br /> the Environmental Protection Agency and Regional Water Quality Control Board and local <br /> agency guidelines for the investigation <br /> 2 . Reconnaissance groundwater samples will be collected in the field in temporarily cased <br /> exploratory boreholes using clean Teflon or disposal bailers The samples will be collected <br /> from temporarily cased exploratory boreholes All sample containers will be properly <br /> prepared, sealed, labeled, and identified Label information will include the date, sampler <br /> name, sampling time, and identification number, and the project name and number <br /> 3 . The sample will be delivered to a State Certified Laboratory within two days of collection <br /> Samples will be kept on ice and/or refrigerated continuously for shipment to the Laboratory <br /> 4 . The sealed sample will only be opened by Laboratory personnel who will perform the chemical <br /> analysis <br /> 5 . The samples will be analyzed according to the approved EPA Method and storage for the <br /> requested analysis <br /> 6 . Groundwater sampling will begin 24 hours following «ell development, following the <br /> procedures detailed below for monitoring well sampling Depth to water measurements are <br /> 40 made to the nearest 0 01 foot a surveyed datum (project or known) and wells are checked for <br /> separate phase product Boreholes are sealed following water sampling <br /> Monitoring Well Construction <br /> 1 . The proper permits will be obtained from the appropriate agency or Water District, using a Well <br /> Inspector as required to be present to witness the installation of the annular seal The soils <br /> borings will be drilled with a continuous-flight hollow-stem auger of at least 3 inches Inside <br /> Diameter (ID) and 6 to 8 inches Outside Diameter(OD) All augers will be thoroughly steam- <br /> cleaned prior to visiting the site The augers will be steamed cleaned between borings at a <br /> location well away from the proposed borings or adequate clean auger will be available to <br /> complete all of the wells without reusing auger sections <br /> 2 . A geologic drilling log will be made of the materials encountered and sample depth for each <br /> boring The soils/sediment lithology will be logged using the Unified Soil Classification <br /> System The log will include field descriptions of the soil lithologic variations, moisture <br /> conditions, geologic data, and any unusual characteristics which may indicate the presence of <br /> chemical contamination <br /> 3 The borings will be advanced to a depth of 45 feet if a saturated zone is not encountered (in <br /> absence of other depth specifications) If a saturated zone is encountered, the boring will <br /> advance no further than 15 feet below first encountered groundwater or 5 feet into the <br /> underlying clay aquitard A seal will be placed in the overdnlled portion of the aquitard <br /> 4 . During the drilling operations, 55-gallon drums will be on site to contain potentially <br /> contaminated soils and rinse water <br /> Wright Environmental Services, Inc rev 6/2/94 <br /> Geoscience Protocols Page 2 <br />