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5.9 Proposed Land Survey of Monitoring Wells and Sample Locations A wellhead elevation survey will be conducted to provide surveyed measuring-point elevations used to assess the elevations of the water table in the monitoring wells. The survey will be conducted by a California Licensed Land Surveyor. The horizontal well locations (x and y) are expected to be accurate to 0.1 foot. The vertical measuring point elevation (z) is expected to be accurate to 0.01 foot. The survey will be conducted in accordance with the State of California Geotracker requirements. Depths-to-water and corresponding water-table elevation information will be logged when the monitoring wells are developed. Utilizing the wellhead elevation survey data, a groundwater gradient map will be prepared utilizing the water table elevations for a geological, three-point solution. A survey of the horizontal locations of the remaining sample locations including the six soil boring along the sewer lateral, the six borings associated with the petroleum hydrocarbon assessment, and the four soil gas samples along the southern boundary of the subject property, will be conducted by a California Licensed Land Surveyor in accordance with GeoTracker requirements. 5.10 Sample Collection Methods The following section provides a description of the sample collection methods that will be used during implementation of the Site SAP. Field documentation forms that will be used during the investigation are presented in Appendix A. 5.10.1 Direct Push Borings Direct push drilling methods, such as Geoprobe, will be used to collect subsurface soil samples for laboratory analysis. Shallow grab groundwater samples will also be collected during direct push drilling activities. Direct push-drilling methods use hydraulic pressure and the weight of the drill rig to advance drill rods into the subsurface. This drilling method is invasive but can be performed quickly while generating relatively little waste. Rods containing clear acetate liners approximately 2 inches in diameter and 4 feet long will be driven to the desired depth. The rods will be retracted, and the acetate liners will be removed for lithologic logging. Soil will be logged using the unified soil classification system (USCS). Soil samples will be collected using an EnCoreTI sampler from the desired sampling depth (three EnCoresT°" per sample). After soil samples have been collected the soil borings will be sealed to grade with a tremie pipe using neat cement grout. The soil borings will be completed under the supervision of a California Professional Geologist. Additional soil samples may be collected at the discretion of the field geologist, based on Site conditions and signs of contamination and/or PID measurements. Groundwater samples will be collected with the direct push equipment using a HydropunchTI to collect depth-specific groundwater samples. A direct-push drill rig (e.g., Geoprobe) will be used to hydraulically advance 13/4-inch diameter, hollow push rods to the bottom of the desired sampling interval. The push rods will then be retracted, exposing a screen and allowing groundwater to infiltrate hydrostatically from the formation into the screen. A small-diameter bailer will be lowered through the push rods into the screen section for sample collection. Upon filling, the bailer will be retrieved and the groundwater will be decanted into the appropriate laboratory-supplied sample containers. Upon completion of sample Sampling and Analysis Plan Tracy Corners Shopping Center 3225 North Tracy Boulevard Tracy,California 95376 Partner Project Number SM14-129814 Docket Number HAS-VCA 14/15-108 August 15,2016 Page 22