ARCHIVED REPORTS XR0001208 - Laserfiche WebLink

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FIELD AND LABORATORY PROCEDURES Exploratory Drilling and Soil and Groundwater Sampling The soil borings were advanced using a direct push cone penetrometer testing (CPT) ng Borings SB-3 and SB-4 were logged by CPT All soil samples for chemical analysis were collected with Enviro-Core® technology and retained in plastic liners, capped with Teflon squares and plastic end caps, and sealed in zip-lock bags The sample containers were placed on ice for transport to the laboratory accompanied by chain-of-custody docu- mentation Down-hole boring and sampling equipment was steam-cleaned prior to and following the completion of each soil boring Down-hole sampling equipment was washed in a tri-sodium phosphate or AlconoxTM solution between samples Discrete groundwater samples were collected in selected intervals based on stratigraphy and field analytical data Samples were collected using a hydro-punch and a stainless steel or Teflon bailer lowered into accumulated groundwater in each boring, then retrieved and transferred into laboratory supplied containers The sample containers were placed on ice for transport to the laboratory accompanied by chain-of-custody docu- mentation Down-hole boring and sampling equipment was steam-cleaned prior to and following the completion of each soil boring Down-hole sampling equipment was washed in a tri-sodium phosphate or AlconoxTM solution between samples • Organic Vapor Procedures Soil samples collected at periodic depth intervals or collected continuously during drilling were screened in the field for ionizable organic compounds using a photo- ionization detector (PID) with a 10 2 eV lamp or a flame ionization detector (FID) The test procedure involved measuring approximately 30 grams from an undisturbed soil sample, and placing this sub-sample in a sealed container (either a zip-lock bag or a mason far) The container was warmed for approximately 20 minutes (in the sun), then the head-space within was tested for total organic vapor, measured in parts per million as benzene (ppm, volume/volume) The instrument was 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 The results of the field-testing are noted on the boring logs PID and FID readings are useful for indicating relative levels of contamination, but cannot be used to evaluate hydrocarbon levels with the confidence of laboratory analyses •'