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MI b 1 115, N. (Modified) and 8020. Portions of each samples were extruded into zip-lock plastic bags for field heddspace measurement of volatile organic compounds with an kNu, photoionization detection meter. Monitor Wel} Construct o Monitor well MW-1 was constructed through the 11 7/8-inch hollow stem augers using 4-inch inside diameter (I.D,), Schedule 40 PVC, 0.02-inch slotted well screen from 12 feet to 34 feet and 4-inch I.D. Schedule 40 PVC well casing from 12 feet to approximately six inches below ground surface. As previously mentioned, the bottom seven feet of the monitor well MW-1 borehole was backfilled with bentonite pellets prior to well construction. Monitor wells-MW-2 through -10 were constructed through the 6 5/8-inch hollow stem augers using 2-inch I.D. , Schedule 40, PVC 0.02- inch slotted well screen and 2-inch I.D. Schedule 40 PVC well casing. y� Monitor wells MW-2 through -10 were all over-drilled from S to 15 feet past the bottom of the screened interval to provide lithologic information + at depth. In each case, the over-drilled portions of the boreholes were backfilled with sodium bentonite pellets prior to well construction. Screened intervals and borehole total depths for the monitor wells are as follows: Screened Interval Total Depth MW- 1 12' - 34' 41' MW- 2 12' - 34' 41' MW- 3 12' - 34' 41' }4W- 4 12' - 24.5' 301 MW- 5 12' - 26.5 40' MW- 6 12' - 28' 40' MW- 7 12' - 30' 40' MW- 8 12' - 28' 40' MW- 9 12' - 24' 29' MW-10 12' - 25' 30' The annular space between the borehole wall and well screen in each boring was filled from the bottom of the screen to 11 feet below ground surface with Clementina #3 filter sand. A bentonite pellet seal was installed in each well from 11 to 9 feet below ground surface, and a neat grout mixture of 94 pounds of Portland Type II cement and six gallons of clean, potable water was placed in each well from a depth of nine feet to ground surface. A PVC slip cap was placed on the top of each well casing. Well heads. consisted of water-tight, locking, traffic rated, monitor well vault boxes with a four inch"wids cement pad to grade. Each monitor well was developed immediately after the bentonite seal was installed and properly hydrated. Monitor wells Mw-1 through -8 were developed with a five horsepower centrifugal pump. Monitor wells MW-9 and ----- 10-are-relatively-low-yielding-and-were-developed--with--a-1--1/2=inch x-3- ---- - --- - ------- ----- x foot, stainless steel bailer. Approximately 110-gallons of water was 11