Patent ID: 8381653

Claim:
A method of charging an upwardly oriented hole with a pumpable material, the method comprising the steps of: providing a laterally expandable retainer in the form of a length of flexible lay-flat tubing which is of smaller length than the hole, which has an inlet at an operatively lower end thereof and an outlet at an operatively upper end thereof and which, in an unexpanded state, has a smaller lateral dimension than the hole; pushing the retainer, in an unexpanded state, upwardly into the hole by means of a suitably stiff charging conduit which is a component separate form the retainer and attached to the inlet of the retainer; pumping material with which the hole is to be charged upwardly into the retainer through the charging conduit such that the retainer fills up and expands laterally into engagement with a wall of the hole; allowing any excess material pumped into the retainer to flow upwardly out of the retainer through the outlet; and after the retainer has been filled with material and the hole above the retainer has been at least partially filled with any excess material, terminating the pumping of the material and closing the inlet such that material is retained in the hole by engagement of the filled and expanded retainer with the wall of the hole.