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F A-5 All samples are collected by experienced Brown and Caldwell field personnel, and placed in containers appropriate to the required analysis. Brass tubes used to collect soil samples are cleaned by washing in laboratory-grade detergent, rinsing with tap water, and rinsing again with deionized water. All glass containers have been precleaned by the manufacturer or at the analytical laboratory according to guidelines established by the U.S. Environmental Protection Agency. Following collection and inspection of soil samples, the ends of the brass tubes are covered with aluminum foil and plastic caps and sealed with plastic tape. Groundwater samples are collected in sampling bottles that have caps with Teflon septa. After filling, the bottles are visually inspected to ensure that no air bubbles remain within. All samples are labeled and then placed in zip-lock plastic bags. Samples are stored and transported in a closed ice chest and protected from meltwater. Samples are stored for analysis no longer than the maximum allowable holding time. Sample identification and chain-of-custody procedures ensure sample integrity and document sample possession from the time of collection to ultimate disposal. Each sample container submitted for analysis has a label affixed to identify the project number, sampler, date of collection, sample location, the monitoring-well number (if appropriate), and a number unique to that sample. That information is recorded on the borehole log or in the field records, along with a description of the sample, field measurements, sampling methodology, names of sampling personnel, and other pertinent field observations. A standard Brown and Caldwell chain-of-custody form is used to document possession of samples from time of collection to arrival at the laboratory. All samples are submitted to an analytical laboratory that has been certified by the California Department of Health Services. The sample-control officer at the laboratory verifies sample integrity and confirms that samples were collected in the proper container, preserved correctly, and that there is an adequate volume for analysis. If these conditions are met, the sample is assigned a unique log number by the laboratory for identification throughout analysis and reporting. The log number is recorded on the chain-of-custody form and in the legally required log book maintained at the laboratory. The sample description, date received, client's name, and other relevant information also are recorded. SAMPLE HANDLING Samples are handled during collection and shipment in such a way as to ensure maximum sample quality and integrity. All samples are collected by experienced Brown and Caldwell field personnel. The samples are collected in containers that are appropriate to the sample material and the required analyses. All containers.have been precleaned by the analytical laboratory or the container manufacturer. All sampling equipment is decontaminated prior to and between use by washing in laboratory-grade detergent, rinsing with tap water, and then rinsing with deionized water.