ARCHIVED REPORTS_XR0005948 - Laserfiche WebLink

Home Browse Search

i Ile 3.2 Soil and Groundwater Investigation Soil and groundwater will be sampled near the former UST to demonstrate the limited nature of the UST release to the subsurface A geoprobe investigation technique will be used to collect both soil Iand groundwater data At the minimum, eleven geoprobe boring locations will be sampled The proposed geoprobe locations are shown on Figure 5 I Each geoprobe test boring will involve collecting soil samples at 5-foot sampling intervals to a total depth of 15 feet, or to a maximum depth at which groundwater is encountered A sample split will ' be evaluated for total organic vapors (TOV) with a phototonization detector (PID) during the investigation If TOV readings greater than 50 ppm are detected, the investigation will be stepped ' out five feet, and an additional boring will be installed to further collect delineation samples Samples will be labeled, capped, and immediately placed into an ice chest or similar container for contaminant ' preservation and submitted under the appropriate chain-of-custody protocol to a California Certified Laboratory Each sample will be analyzed for TEPH using EPA Method 8015 modified for diesel, '* TPH-g using EPA Method 8015 modified for gasoline, and for BTEX and MTBE using EPA Method 8020 I Upon reaching groundwater, the geoprobe will advance an additional two to four feet, and a ' groundwater sample will be collected using a hydropunch sampler The hydropunch utilizes a screened drive tool, which allows the collection of relatively undisturbed groundwater samples ' Groundwater samples will be collected in a clean Teflon bailer and decanted into, laboratory supplied, 40-m1 VOA vials, and placed inside of an ice chilled cooler for transport to the laboratory ' Groundwater temperature, conductivity, clarity (m NTU), and resistivity will be measured and recorded during sampling Chain-of-custody procedures will be followed and documented ' Groundwater samples will be analyzed for the same constituents as noted for soil samples For quality assurance, an additional trip blank will be prepared and submitted for analysis, as will a ' duplicate sample collected from one of the test geoprobe borings The Lcamer Company-UST In%x--m atinn Wnrlplan 5 ' PRE ts%�R97016\97016cal dnckRev 0(lune 1997) 1