| CPC E21D 9/001 (2013.01) [E21D 9/03 (2016.01); E21D 9/06 (2013.01)] | 7 Claims |

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1. A system for constructing an underground tunnel, the system comprising:
directional drilling equipment configured to:
drill a first bore along a first predetermined path through underlying geology, the first bore having a length of at least 25 m; and
drill a plurality of second bores along respective second predetermined paths through the underlying geology, each of the respective second predetermined paths being substantially parallel to the first predetermined path in order to define a substantially prism-shape region therebetween;
a liner disposed within any one of the first bore and the plurality of second bores, the liner having holes therein;
treating equipment configured to treat the underlying geology through the holes in specific pre-defined directions, in advance of excavating the material in order to increase efficiency of excavating the material; and
excavation equipment configured to excavate the material within the substantially prism-shape region defined by the first bore and the plurality of second bores to form a tunnel.
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