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Cutting the Outer Ports and Vent Holes
8) Slide the Port Cutting Guide over the CMT tubing down to Port 1. Align the notch stamped "1" on the Port Cutting Guide with the line you drew along the Channel 1 identifier. Position the Port Cutting Guide so that the depth mark “+” (indicating the centre of the Port) is visible in the window in the center of the Port Cutting Guide (Figure 5). Secure the Port Cutting Guide to the CMT tubing by tightening the knurled Locking Bolts on the underside of the guide (Figure 6). Tighten the bolts, by hand only, to prevent the Port Cutting Guide from moving.
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 Note: When using the Port Cutting Guide, ensure that the cutting bolts are located below the number 1 on the front of the Guide. The locking bolts go below the number 4 on the back of the Port Cutting Guide.
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Figure 5
Figure 6
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9) Next, cut three holes, as described below into Channel 1 using the cutting bolts screwed into the Port Cutting Guide.
Start by threading a cutting bolt into one of the holes located on the same side as the window. Use the hex wrench to tighten the Cutting Bolt. Tighten the bolt a few revolutions, then loosen it one revolution. Continue doing this until the Cutting Bolt "bottoms out" (Figure 7). Remove the Cutting Bolt. There should be a plastic disk inside of the cutting bolt. If there isn’t, re-insert the cutting bolt and repeat the cutting process (make sure that the knurled Locking Bolts are tight). Push out the piece of plastic from the inside of the Cutting Bolt by inserting an Allen wrench through the small hole drilled in the head of the Cutting Bolt (Figure 8 ). Repeat this process to cut all three holes. The two upper holes will provide the port plug access and the lowest hole is the vent hole (Figure 9).
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Figure 7
Figure 8
Figure 9
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Note: The two upper holes allow you to use snips to cut away a panel of plastic between the two holes, creating a 3-inch-long port in Channel 1. The bottom hole is a vent hole. A vent hole is needed to allow air to escape from the channel beneath the monitoring port when the CMT tubing is inserted into the water-filled borehole during well installation.
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10) Loosen the cutting tool and move it “down” the CMT and out of the way. Next, use the snips as shown in Figure 10 to cut out the panel of plastic between the upper two port holes. Do this carefully and keep the snips parallel to the channel side wall to avoid cutting into the walls separating Channel 1 from Channels 2 and 6. Make the opening as large as possible to facilitate the insertion of the expansion plug as described in the next step.
Figure 10
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Note: The vent hole does not allow cross connection with other monitoring zones because the bottom of the channel is sealed with a water-tight plug.
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11) Insert an expansion plug through the opening (Figure 11) so that it seals Channel 1
below the monitoring port and above the vent hole. If necessary, use the torque driver
to gently push the plug into place (Figure 12). Use the snips to trim the port opening if
you have difficulty inserting the plug. Tighten the plug to a torque of 10 inch-pounds
using the supplied torque driver.
Figure 11
Figure 12
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12) The last step in making the Channel 1 port consists of wrapping the stainless steel mesh
around the port, forming a well screen over the opening. Center the mesh over the port
opening and wrap it tightly around the CMT tubing (Figure 13). Use the low profile
Oetiker clamps and pliers to firmly secure the mesh to the tubing. Use two clamps for
each monitoring port (Figure 14). Construction of Port 1 is now finished. You are now
ready to make Port number 2.
Figure 13
Figure 14
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Note: To avoid installing ports in the wrong channels start by positioning the Port Cutting Guide so that the depth mark is visible in the window, then rotate the guide so that the appropriate number (corresponding to the port number) is indexed against the line you drew earlier along the longitudinal Channel 1 identifier. This step is very important
Note: At some sites, you may decide that it is not necessary to monitor every channel. In that case, only cut ports in the desired channels.
When constructing the bottom assembly, only insert the expandable plugs into the monitored channels, leaving the other channels open so that they can fill with water as the CMT tubing is inserted into the borehole (e.g. If only three channels are monitored, only those channels should have plugs inserted at the base.) This reduces buoyancy during well installation.
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13) Slide the Port Cutting Guide down to Port 2. Position the Port Cutting Guide exactly
as you did for Port 1. The depth mark should be visible in the window of the Port Cutting
Guide and the longitudinal Channel 1 identifier should be indexed to the number "1"
stamped on the guide (Figure 15). Now, rotate the Port Cutting Guide (without moving
its position along the CMT tubing) so that the longitudinal line is now indexed to the
number "2" stamped on the guide (Figure 16). This positions the Port Cutting Guide so
that the cutting bolts will cut holes only into Channel 2. Secure the Port Cutting Guide
using the knurled Locking Bolts as before. Cut the two port holes and one vent hole
into Channel 2. Next, loosen the cutting tool and slide it down the tubing out of the way.
Figure 15
Figure 16
14) Snip away the panel of plastic between the upper two holes, creating an opening for Port 2.
15) Next, insert an expansion plug though the opening, positioning it below the monitoring port, and tighten it to 10 inch-pounds as before. Finally, wrap a piece of stainless steel mesh around the opening and secure it with two stainless steel clamps. You have now finished constructing Port 2.
16) Continue the steps described above for Ports 3 through 6.
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