Gas Migration in EBS and Geosphere (GMT) - Cutting through the concrete plug

To make the initial cutting of the concrete plug, a manhole was created by drilling 24 overlapping boreholes through the 2.5 m thick concrete plug.

Some small diameter boreholes were drilled to allow a wire-saw to be used. This allowed large blocks of the concrete plug (2.5 x 0.45 x 0.88m) to be removed. These blocks could then be removed to allow entrance to GMT cavern.

The initial cutting of concrete plug

Cutting of concrete plug

The first excavation of backfill

Removal of the plug sections after sawing

The cores of the concrete plug

Removal of the sawn concrete plug



The GTS underground facilities are also available to interested 3rd parties for underground testing and research. The GTS offers cost-effective access to a fully developed, well characterised underground research facility with round the year logistical support - please contact Dr. Ingo Blechschmidt, Head of the Grimsel Test Site, for further details.