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SOP: Monitoring <br />Well Installation <br />• insulated coolers with ice, when collecting samples requiring preservation by chilling; <br />• monitoring well locks and keys; <br />• well construction materials; and <br />• field logbook. <br />II <br />II <br />II <br />II <br />II <br />F~ <br />IV. Cautions <br />Prior to beginning field work, underground utilities in the vicinity of the drilling areas will be delineated by the <br />drilling contractor or an independent underground utility locator service if monitor well location is within the <br />range of such services. <br />Coated bentonite pellets will not be used in monitoring well construction, as the coating could contaminate the <br />well. Overburden monitoring wells may be installed with Schedule 40 polyvinyl chloride (PVC) to a maximum <br />depth of 200 feet below Bound surface (bgs). PVC monitoring wells between 200 and 400 feet total depth will <br />be constructed using Schedule 80 PVC. Monitoring wells deeper than 400 feet will be constructed using steel. <br />V. Health and Safety Considerations <br />Field activities associated with monitoring well installation will be performed in accordance with the Mine <br />HASP, a copy of which will be present on site during such activities. <br />VI. Procedures <br />The procedures for installing groundwater monitoring wells in soil are presented below: <br />Hollow-Stem Auger, Drive-and-Wash, Spun Casing, Fluid/Mud Rotary, Rotasonic, and Dual-Rotary <br />Drilling Methods <br />1. Locate boring/well location, establish work zone, and set up sampling equipment cleaning area. <br />2. Advance soil boring to depth. Collect soil samples at appropriate interval as specified in the Work Plan <br />and/or FSP. Collect, document, and store samples for laboratory analysis as specified in the Work Plan <br />and/or FSP. A common sampling method that produces high-quality samples with relatively little soil <br />disturbance is the ASTM D 1586 -Standard Test Method for Penetration Test and Split-Barre! Sampling of <br />Soils. Split-spoon samples are obtained during drilling using hollow-stem auger, drive-and-wash, spun <br />casing, and fluid/mud rotary. Rotasonic drilling produces large-diameter soil cores that tend to be more <br />disturbed than split-spoon samples due to the vibratory action of the drill casing. Dual-rotary removes <br />cuttings by compressed air and allows only a general assessment of geology. <br />3. Describe each soil sample, including soil type; color; percent recovery; relative moisture content; soil <br />texture; grain-size and shape; consistency; presence of any staining, sheen, or odor; and any other pertinent <br />observations. Record descriptions in the field logbook. During soil boring advancement, document all <br />drilling events in field logbook, including blow counts (number of blows required to advance split-spoon <br />sampler in 6-inch increments) and work stoppages. Blow counts will not be available if Rotasonic, dual- <br />rotary, or direct-push methods are used. <br />4. Upon completing the borehole to the desired depth, install the monitoring well by lowering the screen and <br />casing assembly with sump through the augers or drill casing. Monitoring wells typically will be constructed <br />of 2-inch-diameter, flush-threaded PVC slotted well screen and blank riser casing. Smaller diameters may <br />ttreros <br />SOPo4-Monitor Well Installation-Mine.tloc <br />