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water measurement will then be collected using an electronic water level. The depth-to-water will be measured to a surveyed mark on the top of the well casing and recorded on the groundwater sample collection record. Groundwater monitoring wells will be developed by surging, bailing, and/or pumping until clean, sediment-free water is produced from the well. During the purging process purge water will be monitored at random intervals for temperature pH, and specific conductance. Once sediment free water is produced and the monitored parameters have stabilized(variations in three consecutive readings not exceeding 10-percent of the readings), the well will be considered fully developed. The length of development time varies, depending upon field conditions. Development water will be contained, on-site, in 55-gallon barrels until the water can be properly disposed. Immediately following development of the well a groundwater sample will be collected for laboratory analysis. Each groundwater sample will be obtained using a pre-cleaned, polyethylene, disposable bailer equipped with a bottom-emptying valve. Samples will be transferred from the bailer to the sample bottles (three 40-m1. volatile organic analysis (VOA) vials, containing approximately 5-ml. (each) of hydrochloric acid) using a bottom-emptying device. Sample bottles will be obtained precleaned from the State certified analytical laboratory. The bottle will be carefully filled to the very top, in order to create a positive meniscus, and sealed with a teflon-lined septa and cap. These precautions aid in eliminating air from the sample. The sample will be visually inspected to ensure that no air bubbles remain within. Samples will be labeled and stored in cooled ice chests until being delivered to the analytical laboratory, under appropriate chain of custody protocol and within the permissible holding time. Sample Handling Samples are handled during collection and shipment in such a way as to ensure maximum sample quality and integrity. All samples will be collected by experienced Brown and Caldwell field personnel. The samples will be collected in containers that are appropriate to the sample material -• and the required analyses. All containers will have been precleaned by the analytical laboratory or the container manufacturer. All non-disposable, down-hole sampling equipment will be decontaminated prior to and between use by washing in laboratory-grade detergent, rinsing with tap water, and then rinsing with deionized water. Each sample container will have a label affixed in the field that identifies the date and time of sample collection, name of sampler,job number, and a unique sample number. This information will be recorded on the boring log or in the field records. Samples will be stored and shipped to the laboratory in a cooled chest. Only analytical laboratories certified by the California Department of Health Services will be used for analysis of samples. A chain-of-custody form will be used to record possession of samples from the time of collection to the time of arrival at the laboratory. The sample-control officer at the laboratory will EA2092\pha [I\workplmdo