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0 <br /> ' Extension Roc! 1 meter(AT675) 48-inch(AT671) or 60-inch(10073) <br /> ' \--Etension Rod Coupler(AT68) <br /> ' Extension Rod Quick Links(AT694K) includes(1)AT696 and(1)AT695 <br /> Female Quick Lin Male Quick Link <br /> ' Extension Rod Coupler --Extension Rod Coupler <br /> (AT696) (AT695) <br /> 1 L= <br /> qD=�:= <br /> 7==� �j <br /> ' Extension Rod Jig---Top View Extension Rod Jig—Side Yew Extension Rod Handle <br /> (AT690) (AT690) (AT69) <br /> FIGURE 5 8 <br /> Geoprobe Extension Rods and Accessories <br /> d) Place a Screen Push Adapter on the end of an Extension Rod Insert the adapter and extension rod <br /> into the PVC riser and hold either by hand or with an Extension Rod Jig Attach additional extension <br /> rods with Extension Rod Couplers or Extension Rod Quick Links until the push adapter contacts the <br /> bottom of the screens (Fig 5 9) Place an Extension Rod Handle on the top extension rod after <br /> ' leaving 3 to 4 feet(I to 1,2m)of extra height above the last probe rod <br /> e) Slowly retract the probe rods while another person pushes and taps on the screen bottom with the <br /> extension rods (Fig 5 9) To ensure proper placement of the screen interval and to prevent well <br /> damage,be careful not to get ahead while pulling the probe rods The nsers should stay in place once <br /> the probe rods are withdrawn past the screens Retrieve the extension rods Place the plug back into <br /> the top riser and secure it with duct tape if necessary <br /> ' 54 Installing grout barrier <br /> The natural formation will sometimes collapse around the well screens and PVC riser as the probe rod <br /> string is pulled back This provides an effective barrier between the screens and grout material used to <br /> seal the well annulus if the formation does not collapse, a sand barrier must be installed from the <br /> ' surface This portion of the well installation procedure is important because an inadequate barrier will <br /> allow grout to reach the well screens Grout contamination can produce non-representative samples and <br /> retard groundwater flow into the well <br /> I Using a Water Level Indicator or flat tape measure,determine the depth from the top of the PVC riser <br /> to the bottom of the riser and probe rod annulus Two scenarios are possible <br /> Standard Operating Procedure Page 15 1 O-in x 2 5-in OD Prepack Screen Monitoring Well <br />