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Mr. Christopher Cochrane California Regional Water Quality Control Board July 31, 2000 Page 2 Phase H of the pond investigation involves the installation of three groundwater monitoring wells to confirm the direction of groundwater flow and evaluate the potential migration of cherry processing brine in groundwater beneath the site and vicinity. The proposed monitoring well locations are shown on Figure 2. The field and analytical methods are described in the following sections. FIELD METHODS Phase H of the pond investigation involves the installation of three groundwater monitoring wells. The field activities will be conducted in accordance with the attached Geomatrix environmental field protocols. Prior to initiating field activities, a site health and safety plan will be prepared for the field activities. A drilling permit will be obtained from the San Joaquin County Public Health Services/Environmental Health Division(PHS/EHD), and Underground Service Alert will be notified for utility clearance. Soil cuttings,purge water, and equipment decontamination water generated from the field sampling activities will be temporarily stored in sealed and labeled 55-gallon drums to be placed on-site for later disposal by Dole. The borings for the monitoring wells will be advanced to a depth of approximately 80 feet bgs using the hollow-stem auger method. Soil samples will be collected at 5-foot depth intervals from the boring for lithologic logging and field screening. The soil samples will be described using the Unified Soil Classification System visual-manual procedure (American Society for Testing and Materials Method D 2488). The wells will be constructed similar to the existing wells and will have machine-slotted screen intervals from about 60 to 80 feet bgs. The wells will be developed by surging and bailing until the water produced is relatively free of suspended sediments. Following development, elevations of the three new wells will-be surveyed relative to mean sea level by a California-licensed land surveyor. The wells will be allowed to equilibrate with the formation for a minimum of 1 week prior to sampling. Prior to purging the wells,water level will be measured in each of the six wells at the facility(Figure 2). The wells will be purged using a submersible electrical pump. A minimum of four casing volumes of groundwater will be purged from each well prior to collecting a groundwater sample. During purging, field parameters will be measured including pH, temperature, electrical conductivity, dissolved oxygen, and oxidation-reduction potential. After purging, groundwater samples will collected from each well. Samples will be sealed, labeled, and placed immediately into an ice-cooled chest for subsequent delivery to a laboratory for chemical analysis under chain-of-custody procedures. L\PROJECr16508.000\doc=ent\6508-02.do c