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S E C O R ATTACHMENT 1 FIELD AND LABORATORY PROCEDURES Soil Borings and Sampling Soil borings will be advanced to a depth of approximately 35 feet bgs using Geoprobe® direct push equipment (first groundwater is expected at approximately 30-34 bgs). The borings will be logged by an attending SECOR geologist using the ASTM D-2488 — Standard Practice for Description and Identification of Soils (Visual-Manual Procedure) and standard geologic techniques. Soil samples for logging from the borings will be collected continuously. All soil samples for chemical analysis will be retained in acetate liners, capped with Teflon squares and plastic end caps, and sealed in clean zip-lock bags. The samples will be placed on ice for transport to the laboratory accompanied by chain-of- custody documentation. All down-hole drilling and sampling equipment will be steam- cleaned following the completion of the soil boring. Down-hole sampling equipment will be washed in an alconox solution between samples. Groundwater samples will be collected from each boring using a hydropunch. Groundwater will be retrieved using either a stainless steel or Teflon bailer. Groundwater samples will be placed into laboratory supplied containers and placed on ice for transport to the laboratory accompanied by chain-of-custody documentation. Sampling equipment will be steam- cleaned prior to and following completion of each sample. Organic Vapor Procedures Soil samples will be analyzed in the field for ionizable organic compounds using a photo- ionization detector (PID) with a 10.2 UV lamp. The test procedure will involve measuring approximately 30 grams from an undisturbed soil sample and placing this subsample in a sealed container. The container will be warmed for approximately 20 minutes in the sun, then the head-space within will be tested for total organic vapor, measured in parts per million as benzene (ppm; volume/volume). The instrument will be calibrated prior to drilling using a 100-ppm isobutylene standard (in air) and a sensitivity factor of 55, which relates the photo-ionization potential of benzene to that of isobutylene at 100 ppm. PID readings are useful for indicating relative levels of contamination, but cannot be used to evaluate hydrocarbon concentrations with the confidence of laboratory analyses. Laboratory Procedures for Soil and Groundwater Samples Selected soil and groundwater samples will be submitted under chain-of-custody documentation to a California State certified laboratory and analyzed for the presence of TPHg and methanol by EPA Method 8015, BTEX, MtBE, TBA, DIPE, EtBE, TAME, 1,2-DCA, and EDB by EPA 8260.