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M CDIM Standard Operating Procedure 2.2 Surface and Shallow Soil Sampling N 0 1 N i R R I N 0 Rev.0 1/27/2022 the sample for direct transfer into glass jars. The exact methodology to be used will be specified in the project work plan. When using the coring device, a sample sleeve (brass, stainless steel, Lexan, etc.) is inserted into the trailing end. The trailing end is then connected to a piston-type drive hammer. The core is driven into the soil by using the hammer (or pushed in the case of very soft soil) until the trailing end of the sleeve is at the soil surface. In this manner, a relatively undisturbed sample is collected in the sleeve. When the device is retrieved, check to see that soil recovery is adequate in the sample sleeve. If there is sufficient recovery, mark or note the leading (deeper) end of the sample sleeve to avoid confusion. The sample can then be sealed with Teflon tape, capped, handled, secured, and shipped in the sample sleeve. 3.6 Subsurface Soil Sample Collection using an Excavator Bucket There are two primary methods that can be used when collecting soil samples using an excavator bucket: 1) the excavator bucket is placed on the ground and the sample is collected from within it while the excavator is in neutral or the power is turned off or 2)the excavator bucket is emptied outside of the guardrail (or safety exclusion zone for the excavation) and the sample is collected from that the resulting soil pile. In the second scenario, the bucket should be emptied a safe distance from the excavation or other machinery. Distances will vary depending on site conditions. In either scenario, a sediment or soil sample can be collected by using tools such as a shovel, trowel, or stainless steel spoon/scoop, disposable scoops, etc. These tools can be used to scoop or collect soil/sediment and directly transfer the matrix into a pre-cleaned sample container (e.g., glass jar, brass sample sleeve, etc.). In addition, the sample should be collected from the center of the excavator bucket or pile, in an effort to minimize sample disturbance and the introduction of outside contamination. The project work plans will specify the type of sampling equipment and sample containers to be used. If sampling for non-volatile compounds such as metals or polychlorinated biphenyls (PCBs), sample collection from an excavator bucket or soil pile may also be satisfactory and can help reduce the physical safety hazards associated with entering an open excavation or trench. If sampling for volatile compounds, such as solvents and fuels, an undisturbed sample collected with minimum potential for volatilization is required. To do this, the sample should be collected directly from the undisturbed sample location (i.e. an excavation sidewall) such that little to no head-space exists in the sample container. However, this method of sample collection is limited to situations where the excavation can be entered safely. The exact procedure to be used will be specified in the project work plans. The sampling event should be documented in the Daily Field Activity Log as specified in the project work plan. Descriptions of any examined core material should be recorded in the CDIM Boring Log Document. Appropriately preserve, handle, package, and ship the samples per the project work plans and Chain-of-Custody SOP (1.0). 3.7 Subsurface Soil Sample Collection from an Open Excavation If collecting samples from open trenches/excavations, borehole/sidewall stability should be maintained to prevent the recovery of slough in the samples. If sloughing cannot be controlled, then another sampling methodology may have to be considered. Additionally, the Occupational Safety and Health Administration (OSHA) and California-OSHA require vertical-walled open trenches or pits to be braced or shored if they are deeper than 5 feet, unless the walls are comprised entirely of stable rock. Alternatively, the trench or open excavation walls must be benched or sloped (slope will be determined by soil type). Lack of soil stability may require a flatter slope. Walls that appear stable can collapse or large slabs may dislodge from the trench 4