Introduction

The Solinst Model 403 CMT Multilevel System for monitoring wells represents a significant improvement in multilevel groundwater and soil gas monitoring. The CMT System provides the simplicity of a bundle type installation with the benefits of backfilling or sealing around a single tube.

This manual describes the above-ground assembly of CMT wells. This consists of creating intake ports in the various channels at the desired depths, installing water-tight plugs below each intake port, adding mesh screens, sealing the bottom of the tubing, and attaching low-profile borehole centralizers to the tubing, or installing Sand and Bentonite Cartridges.

Assembling CMT wells is straightforward and can be performed by either drilling contractors or environmental consultants, however Solinst offers training to ensure proper installation. The wells can be assembled on site while the borehole is being drilled or, off site and then transported to the job location. While the assembly of CMT wells is not difficult, it is important to follow all of the steps described in this manual. It is especially important when creating the monitoring ports to avoid cutting into one of the adjacent channels. Doing so creates a hydraulic connection between the two channels that cannot be repaired. Please read this manual carefully before assembling your first CMT well. In addition we suggest that you practice making one or two ports in a short section of CMT tubing before starting out on the real thing.

Installing CMT wells can generally be done in three ways:

1. The simplest way is to allow the formation sediments to cave around the CMT.
2. A traditional burial of the CMT by dropping layers of sand and bentonite in a depth-discrete sequence.
3. For the 1.1" (28 mm) 3 Channel CMT System, use specially designed Sand and Bentonite Cartridges.