A New Inexpensive Multi-Level System for Fractured Rock Sites and Sediments

Boreholes in fractured rock are often instrument with a variety of multi-level systems (MLS) ranging from cluster wells, nested wells, CMTs, and several other systems which are installed with backfill between the casing and the borehole wall. The cost of the several systems varies dramatically depending on the materials and labor involved and also the sampling methods and the methods for measuring head at the several different elevations are variable. This presentation describes a different method devised by FLUTe which has two different aspects from the usual FLUTe methods of everting liners. A feature of the design is it can be used in highly unstable rock formations and even in sediments instead of only open stable boreholes. The new method, called a Cased Hole Sampler (CHS), has two forms: peristaltic sampling for shallow water tables and positive displacement pumping system for deep water tables. The CHS is not limited to cased holes and has been used in uncased holes. The new installation technique lowers the flexible liner assembly with the associated tubing, ports and spacers directly down the borehole or casing. In deep open stable holes a removable protective sheath avoids the possible abrasion of the liner.