ARCHIVED REPORTS XR0012588 - Laserfiche WebLink

Home Browse Search

r 3.2 WELL CONSTRUCTION DETAILS Planned well locations are depicted on Figure 3. All wells will be constructed using- four-inch diameter schedule 40, threaded polyvinyl chloride (PVC1 casing and threaded PVC 0.010 inch slotted screen. Twenty feet of screen, coupled to 20 feet of blank casing, is anticipated in the monitoring wells which will Extend approximately five feet above the previously encountered saturated zone to accommodate seasonal groundwater fluctuations (Figure 4). The screen will extend approximately 15 feet below the previously encountered water table. Each well will be fitted with a friction end cap. The annulus will be packed with clean #2/12 sand from the well base to two feet above the perfavation zone. The arinular seal will extend from the top of the gravel pa;:k to the surface, and will be constructed of two feet of bentonite pellets overlain by cement grout. Each well will be labeled, fitted with a locking cap and enclosed within a flush mount steel �r. utility y box. Twenty five feet of screen is anticipated in the vadose zone wells coupled to three feet of blank casing (Figure 5). Each well will be fitted with a friction end cap. The annulus will be packed with clean #2/12 sand from the well base to one foot above the perforation. zone. The annular seal will extend from the top of the gravel pack to the utility box and will consist of one foot of bentonite pellets overlain by cement grout. Each well will be labeled, fittedwith a locking cap and enclosed in a steel street box. 3.3 SURVEYING AND DATER LEVEL MEASUREMENTS The ground surface and top of each monitoring well casing will be surveyed to the nearest 0.01 foot above mean sea level. Survey measurements for all well casings will'be made relative to the north side of the casing. The survey data will be used to calculate well elevations, groundwater levels, and produce a groundwater contour map, dater levels will be measured immediately prior to sampling using a conductivity based water level indicator. 3.4 WELL DEVELOPMENT AND SAMPLING The monitoring wells will be developed by hand bailing at least five well volumes of water, while utilizing a surging action, from each well using one 7 4 -A:ENG:9205/O31291