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Additional Soil and Groundwater Investigation Report Canepa's Car Wash(Pacific Avenue) January 21,2002 Page 5 geological boring logs in Appendix C. Well collar elevations for all of the monitor wells are included in Table 2, below. TABLE 2 Monitor Well Elevation Survey Details Monitor Well MW-1 MW-2 MW-3 MW-4 MW-5 MW-6 MW-7 MW-8 MW-9 MW-10 MW-11 MW-12d Previous Survey 13.45 13.27 13.50 13.82 12.69 11.62 13.18 13.26 NA NA NA NA Elevation New Survey 15.48 15.29 15.53 15.83 14.71 14.89 15.80 15.31 14.84 14.72 15.I2 14.99 Elevation Elevation 2.03 2.02 2.03 2.01 2.02 3.27 2.62 2.05 NA NA NA NA Difference(feet) Screen Interval 50-70 50-70 50-70 50-70 50-70 45-65 45-65 45-65 1 25-45 25-45 25-45 I00-110 (feet bgs) Monitor well elevations are in feet above mean sea level referenced to NAD 83 and NAVD 88 vertical datum, NA=Not Available 3.5 MONITOR WELL DEVELOPMENT On October 23, 2001, monitor wells MW-9, MW-10, MW-11, and MW-12d were developed using a Grundfos Redi-Flog stainless steel submersible pump and by surging and bailing the groundwater using a stainless steel bailer. All wells were developed until the discharge water was relatively free of sediment (clear of particles visible to the unaided eye). All well-development pump equipment was cleaned prior to use in each well by washing in a solution of laboratory-grade, non-phosphate detergent and de-ionized water, and double-rinsing with de-ionized water. Groundwater well development logs are included in Appendix D. 3.6 GROUNDWATER SAMPLING Groundwater samples for laboratory analysis were collected from the new monitor wells on October 25, 2001, as part of a quarterly monitoring event. Prior to sample collection, the static water level in each well was measured to the nearest 0.01 foot with a battery-operated water-level meter. The monitor wells were purged using a submersible pump or disposable bailer until the temperature, electrical conductivity, and pH of the water stabilized. At least three casing volumes of water were purged from each monitor well. Groundwater monitoring field forms are included in Appendix D. The groundwater samples were collected into the sample bottles directly from the outlet of the t, 'L.1. discharge +„b,;,, -r +l,e I,,,++-- f+I. 1.,.,1 .i' bla $u v�it4r5iu14 pump u�o�.rrarge �uviug �r ii0 41 Luo.. vv«vii■ Oi ui�. UU11%W10 u$Iiag u u7SpvSa water sample was collected into three 40-m1 volatile organic analysis (VOA) vials. Each sample container was labeled for sample identification and placed in a cooler chilled with blue ice. Upon completion of the fieldwork, the water samples were delivered under chain-of-custody procedures to GeoAnalytical Laboratories, Inc., in Modesto, California. 3.7 SOIL SAMPLING Soil samples for laboratory analysis were collected into clean brass rings using an 18-inch California modified split spoon sampler at five-foot depth intervals. The middle brass ring from the sampler was i I CONDOR I I