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CIMM CDIM Standard Operating Procedure 2.1 Subsurface Soil Sampling '"°'"""'"° Rev.1 10/23/2020 of the volatiles, the split spoon sampler should not be driven until the sampling team is ready to process the sample. Additionally, during drilling, vapors in the breathing zone should be monitored according to the project work plan, the health and safety plan, and the Drilling SOP. 3.5 Continuous Core Methodology Continuous core sampling system methods may be used where continuous soil cores are to be recovered by direct push coring methods (e.g., Geoprobe or Envirocore). The continuous core sampling method uses a core barrel to recover the soil core from the interval the barrel is advanced through. The barrel is recovered after the total depth of the boring is attained. To begin, both the core barrel (inner sampling rod) and outer casing are simultaneously driven into the ground. If the desired sample depth does not start at the ground surface, the inner sampling rod will often contain a disposable tip that can be pushed off once the inner rod is at the desired upper sampling interval. Upon reaching this upper interval, the inner rod is pulled out of the borehole, opened, and sample sleeves (typically plastic) are placed within the inner rod. The inner rod is then lowered back through the outer casing until the upper interval is reached. At this point, both the inner rod and outer casing are advanced simultaneously and as a result, the inner rod is filled with the soil core. Once the soil has been continuously cored to the desired bottom depth, the inner rod is extracted once more and the sample sleeves, filled with soil core, are removed. After extrusion, new sleeves are inserted into the sample barrel, which is then lowered back into the borehole. An additional three or more feet of inner rods and outer drive casing can be attached, and the process is repeated until the desired depth is reached. Repeat this sampling procedure continuously until the bottom of the borehole is reached and/or the last sample is collected as specified in the work plan. 3.6 Non-VOC Sample Collection Soil samples are collected in 1.5- to 2-inches diameter sleeves inside the inner sample barrel or sampler in both the split-spoon and continuous core. The inner sleeves are then given to the site geologist or engineer to prepare for chemical analysis and for lithologic description. During sample collection using a hollow-stem drilling method, observe and record the amount of sample recovery and blow count for each 6-inch sleeve on the Borehole/Well Construction Log. Any observed field problems associated with the sampling attempt (e.g., refusal) or lack of recovery should also be noted. Selecting which sleeve to submit for analysis is based on five factors: • Judgment that the sample represents relatively undisturbed intact material, not slough; • Proximity to the drive shoe; • Minimal exposure to air; • Lithology; and • Obvious evidence of environmental contamination in the sample. The project work plans will specify which sample sleeves should be submitted for specific analyses and confirm the selection criteria. To secure the sample inside the sleeves, place teflon 5