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ENCLOSURE A <br /> SAMPLING TECHNIQUES <br /> Proper sampling techniques were followed to assure that samples represented actual field <br /> conditions and that samples were labeled, preserved, and transported properly to retain sample <br /> integrity This exhibit describes procedures followed by Acton • Mickelson • van Darn, Inc <br /> (AMV), during collection of samples of subsurface soil and ground water Sampling guidance <br /> documents from the American Society of Testing and Materials (ASTM), U S Environmental <br /> Protection Agency (EPA), and California Department of Health Services (DHS) were followed <br /> for all sampling procedures Actual sampling procedures employed were based on field <br /> conditions and may differ from those described here <br /> 1.0 WATER LEVEL AND LIQUID-PHASE HYDROCARBON (LPH) <br /> THICKNESS MEASUREMENTS AND GROUND WATER SAMPLING <br /> 1.1 Water Level and LPH Thickness Measurements <br /> The static water level and/or LPH thickness in each well was measured prior to purging or <br /> sampling <br /> The depth to water/product was measured using an electronic interface probe The wire of the <br /> interface probe is marked at 0 01 foot intervals One tone is emitted from the interface probe <br /> if LPH is encountered, another tone for water The wire of the interface probe was lowered <br /> slowly until LPH or water was encountered At this point, the mark on the interface wire <br /> opposite the permanent reference point on the top of the well casing was read to the nearest <br /> 0 01 foot and recorded If the first encountered substance was LPH, the probe was lowered <br /> until the tone corresponding to water was emitted This depth was also recorded The <br /> difference between the two depths corresponds to the LPH thickness The interface probe was <br /> rinsed in detonized water between measurements in different wells <br /> A permanent reference point was marked on the well casings The permanent reference point <br /> on the well casings was surveyed to a common reference point All well casing riser elevations <br /> are known to within 0 01 foot <br /> Prior to well development, a disposable bailer was used to collect a sample of LPH, if present <br /> in a well, for subjective analysis The sample was collected by gently lowering the bailer <br /> approximately one-half the bailer length past the air/LPH interface The appearance (color, <br /> opacity, "freshness") was described and noted on field notes <br /> LAPT025%1AF <br />