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A4OM 4.2.3 Coarse Materials In coarse materials, use direct push equipment with rods used to install mini-wells, (e.g. outer 2.125 in. diameter rods). • vapor well will be installed in the inside of the tool string • sand pack and granular bentonite will be delivered down the inside of the tool string during removal of the tool string Do not to pull the casing/tubes out of sand pack when extracting the tool string. 4.2.4 Tighter Soils • Advance the direct-push rod or hand auger (e.g. small diameter rods with 2 in. pre- probe, or 2 in. hand auger) to the desired depth, then remove the rod or auger completely. • Provided the borehole will stay open, vapor wells can be installed. • Inspect the borehole to verify the desired depth is achieved, prior to well installation. 4.3 VAPOR WELLS AND NESTED WELLS A vapor well point will be: • Probes will be targeting the interval approximately 5 foot below ground surface (bgs.) within the overburden above bedrock (shallow) and 15 foot bgs or 1 foot above capillary fringe (deep), if shallower than 15 foot. • Approximately 6 inches of sand will be placed in the bore hole. • The probe will be placed on top of the sand and 6 inches of additional sand will be added to the bore hole. • Cut probe tubing to an appropriate length to reach the surface, allowing enough material for surface completion. • The probe will be centered in approximately 1 foot of sand in the bottom of the borehole. • A granular bentonite plug, will be placed directly above the sand pack, with one foot of dry bentonite followed by a foot of hydrated bentonite (approximately 1 foot of granular bentonite and 120- 150 ml of de-ionized water). Take care to ensure that the seal material does not intrude into the sand pack. If the boring contains dry bentonite, take care to fully hydrate the bentonite. Placing the bentonite in small increments (e.g., < 6 inches)followed by water is helpful. Alternatively, the bentonite can be added using a combination of dry and hydrated bentonite. • Sand will then be added to next sampling interval. • Second vapor probe will be placed in above six inches of sand.