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prior to installing the bentonite seal in order to maximize the filtering capacity of the wells. Full development of the wells will be performed a minimum of 48 hours after well completion. This will include additional surging and bailing along the screened interval to remove fine particles from the sandpack. After several volumes of the water have been removed, the wells will be pumped (or bailed) until the discharge water is relatively free of sand or silt. ' 5.0 SOIL AND GROUNDWATER SAMPLE HANDLING PROCEDURES The following procedures will be used for soil and groundwater sample handling: ' 1. Each retained sample will be labeled using waterproof ink with the project name, borehole I.D. number, sample depth (for soil samples), time and date collected, and the initials of the sampler. 1 401111,9111 A-5 4.4 Monitoring Well Sampling Procedures Each groundwater monitoring well will be purged prior to collecting groundwater to five ' samples for chemical analyses. During the purging process, approximately three well volumes of groundwater will be discharged from the well using either a centrifugal pump or bailer. The well will be properly purged when the physical parameters of the groundwater (i.e., pH, temperature, and conductivity) have stabilized. If the well is evacuated prior to the removal of three to five well volumes, a sample of the groundwater will be collected when the water level is sufficient to provide a representative sample (i.e., return to 80% or more of the static water level). Samples of the groundwater will be collected from each monitoring well using a Teflon® or stainless steel bailer which has been washed in a solution of Alconox ' followed by several rinses with potable or deionized water, or using a disposable bailer which was removed from its factory protective cover immediately prior to sampling the well. The groundwater samples collected from each well will be decanted into the ' appropriate sample containers for each analyte. Sample containers will be chemically preserved by the laboratory prior to going into the field. Care will be taken when transferring the water from the bailer to the sample containers to avoid turbulence and all ' VOA vials will be filled above the top of the opening to form a positive meniscus so that no headspace will be present. 4.5 Water Level Measurements and Surveying Top of Casing of Monitoring Wells After the water levels in the wells have stabilized, the depth to water in the wells will be ' measured to an accuracy of 0.01 ft using an electronic immersion probe. The top of casing of each well will also be surveyed to a common datum to convert depth -to -water level measurements to relative groundwater elevations. All surveyed elevations will be t performed to an accuracy of 0.01 ft. All survey locations in the X -Y coordinate will be taped to an accuracy of 0.1 ft. ' 5.0 SOIL AND GROUNDWATER SAMPLE HANDLING PROCEDURES The following procedures will be used for soil and groundwater sample handling: ' 1. Each retained sample will be labeled using waterproof ink with the project name, borehole I.D. number, sample depth (for soil samples), time and date collected, and the initials of the sampler. 1 401111,9111 A-5