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Momtorin Well Develo ment and Groundwater Sam lin The fluid level in the monitoring well was measured using an electric water level indicator Prior to ' sampling, the well was purged until water quality measurements had stabilized or a minimum of five casing volumes of groundwater were removed using an electric submersible pump The pH, conductivity, and temperature were periodically monitored during the pumping of the well and ' recorded on Monitoring Well Sampling Data Sheet, a copy of which is included in Appendix C of this report Following purging, a groundwater sample was collected from the well with a disposable bailer The collected water was decanted into appropriate sampling containers Each sample was labeled, chilled, and transported to Zymax utilizing standard chain-of-custody procedures ' Quality assurance/quality control (QA/QC) procedures were adhered during the field activities These procedures included decontaminating the sampling equipment prior to, and following, each use Decontamination consisted of washing the equipment in an Alconox® solution, followed by a fresh water rinse, and subsequent distilled water rinse Auger flights and drilling rods used during the advancement of the boring were steam cleaned prior to use Cone Penetrometer Test (CPT) Two CPT soil borings (CPT-A and CPT1) were advanced to a maximum depth of approximately 30 meters (100 feet) using a truck-mounted cone penetrometer rig The work was performed using a 22,500-kilogram (25 ton) CPT rig and support rig The dead weight of the CPT rig was used to advance the 5 08-centimeter (2-inch)-diameter cone penetrometer using a hydraulic ram located at ' the center of the truck As the cone penetrometer was advanced, it measured cone bearing tip resistance, sleeve friction, friction ratio, and pore water pressure The data were processed in real time in the field to expedite interpretation of subsurface conditions The CPT borings were performed to obtain deep lithologic data on the aquifer and to collect four vertically discreet groundwater samples with the hydropunch bailer One boring consisted of a pilot hole to determine the stratigraphy and the groundwater target zones The second boring was used to obtain groundwater samples from the targeted zones The CPT log indicated that possible water bearing zones were located at intervals of 14 to 15 meters (48 to 51 feet), 16 5 to 17 4 meters (55 to 58 feet), 18 3 to 18 9 meters (61 to 63 feet), 19 5 to 20 1 meters (65 to 67 feet), and 21 to 21 6 ' meters (70 to 72 feet) The boring was terminated at 30 meters (100 feet) to prevent penetration of a potential underlying confining layer that was encountered below approximately 21 6 meters (72 feet) The upper zone, 14 to 15 meters (48 to 51 feet), was found not to contain an adequate amount of water to sample Water samples were collected from the four lower zones Groundwater samples were collected at the target zones by setting a 1 5-meter (5 foot)-screen with the Protect No 58475-06-02 -6- December 26,2001 1