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sample identification number, borehole number, sampling depth, sample collection date and time,the sampler's name,job number, etc. The sample is then annotated on a chain-of-custody form and placed in an ice-filled cooler for transport to the laboratory. The remaining soil samples are used for soil classification and field evaluation of headspace volatile organic vapors, where applicable, using a PID or flame-ionization detector calibrated to a calibration gas(typically isobutylene or hexane). VOC vapor concentrations are recorded on the boring logs. A physical description of the encountered soil characteristics (i.e. moisture content, consistency, odor, color, etc.)and soil type as a function of depth are indicated on the boring logs. In addition, the sample recovery and sampler penetration are also noted on the boring logs. The sampled soils are classified in accordance with the USCS. STANDARD PROCEDURE FOR EQUIPMENT DECONTAMINATION Equipment that could potentially contact subsurface media and compromise the integrity of the samples is carefully decontaminated prior to drilling and sampling. Drill augers and other large pieces of equipment are decontaminated using high pressure hot water spray. Samplers, groundwater pumps, liners and other equipment are decontaminated in an Alconox scrub solution, and double-rinsed in clean tap water rinse followed by a final distilled water rinse. The rinsate and other wastewater are contained in 55-gallon, DOT-approved drums, labeled(to identify the contents, generation date and project) and stored on-site pending waste profiling and disposal. STANDARD PROCEDURE FOR GROUNDWATER SAMPLING Depth to Groundwater/LPH Thickness Measurements Prior to purging each of the wells, the depth to groundwater and thickness of liquid phase hydrocarbons (LPH), if present, within each well casing is measured to the nearest 0.01 foot using either an electronic Solinst water level indicator or an electronic oil-water interface probe. Measurements are taken from a point of known elevation on the top of each well casing as determined in accordance with previous surveys. Groundwater Monitoring Well Purging Groundwater wells will be purged prior to sampling with a bailer or groundwater pump. Purge water may be contained on-site in 55-gallon DOT-approved drums. To help assure that the collected samples were representative of fresh formation water,the conductivity, temperature, and pH of the delivered effluent are monitored and recorded using a Cambridge Hydac meter or another meter similar in nature during purge operations. Purge operations are determined to be sufficient once successive measurements of pH, conductivity, and temperature stabilize to within +1- 10 percent.