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wood. advancing the borehole to the targeted total depth (approximately 55 feet below ground surface), monitoring well MW-17 will be constructed within the augers using 2-inch-diameter Schedule 40 PVC blank casing and 10 feet of slotted (0.020 slots) screen. Centralizers will be placed along the casing every 20 feet to keep the casing in the center of the borehole. The annular space between the monitoring well screen and surrounding formation will be backfilled with Cemex brand #2/12 or#3 sized filter pack sand (or equivalent), which will be placed such that the top of the filter pack extends at least 1 foot above the screened interval. At least 2 feet of medium bentonite chips will then be placed above the filter pack sand and allowed to hydrate in place. The remaining annular space will be sealed using Portland cement mixed with 3-5% bentonite gel (cement-bentonite grout). Annular materials will be placed at depth within the augers to prevent bridging or borehole collapse. Monitoring well MW-17 will be completed with a traffic-rated, flush-mounted well box. A locking, watertight plug will be placed in the top of the monitoring well casing. Wood will contract a Professional Land Surveyor to survey the location of MW-17 following installation. A.2.1.2 Monitoring Well Development At least 48 hours after installation, the new monitoring well will be developed using a combination of bailing, surging, and purging until the water is relatively visibly clear and field parameters (temperature, pH, turbidity, and specific conductance) are relatively stable (i.e., parameter values change less than 10 percent between three sequential measurements). These parameters and total volume of water removed will be monitored during well development and recorded on a well development record. At least 10 well casing volumes of water will be removed from the well during development. If water was added in the outer casing during borehole advancement through the screen interval, an effort will be made to purge an equivalent volume of water from the well during well development to the extent practical. A.2.1.3 Groundwater Sampling Water level measurements will be collected in newly installed monitoring well MW-17 prior to groundwater sampling. The water levels will be measured with an electric sounder that is graduated to the nearest 0.01 ft. Following the measurement of depth to water, the wells will be purged. Monitoring well MW-17 will be sampled using standard low-flow purging and sampling techniques with a bladder pump at a rate of no more than 500 milliliters per minute, A-2 https://woodplc.sharepoint.com/teams/OlinTracy/Shared Documents/General/03.0 DocCtrl/2022 Decomm M/Revised Decomm M/04_Appendices/App A_methods.docx