If you are monitoring five zones or less, using a 7-Channel CMT Multilevel System, you can take advantage of all seven channels by duplicating channels/ports to the same depth. You can measure water levels in one channel, and have the other channel available for sampling at the same depth.
Typically, the four primary ports would be Channels 7, 6, 5, and 4. The three duplicated (or secondary) ports would be constructed in the outer channels 3, 2, 1. To maintain the structural integrity of the CMT, it is recommended to construct the dual ports in opposite channels, i.e. Channel 4 would pair with Channel 1. Channel 7, the central hexshaped channel, would not be duplicated.
Constructing two monitoring ports at the same depth can be achieved by using a 7CH Standard Port Assembly (pt#106278), and an additional 7CH Standard Pie Plug Seal Assembly (pt#106861) that consists of two pie plugs (one to seal the secondary port opening and the other for the base of that channel). The port screen from pt#106278 wraps around both port openings.
See the 7-Channel CMT Multilevel System Assembly Manual for detailed port construction instructions.
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