(57) A method of repairing an underground drainage pipe, conduit or passageway (12, 142),
by inserting a liner (40, 144) and then launching a pipeline pig (10, 110) through
the pipe which simultaneously creates multiple holes (60) through the liner (40, 144)
and the pipe wall (24). The pipeline pig (10, 110) is also described having a number
of cutting elements (54, 148) arranged substantially symmetrically about a central
axis (52) which can be extended to drill or jet through the liner (40, 144) and wall
(24). Existing conduits are thus made selectively permeable.
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