Environmental cut-off and drain

Abstract From the Canadian patent

High density polyethylene sheets are sealed at their lateral edges to form a sheath or envelope for sandwiching a drain mesh therein. A plurality of spaced apart bore holes is formed along the line of the cut-off and drain barrier and a coupling member is positioned, one in each bore hole respectively, each coupling member having at least one locking keyway slot formed in u side thereof. These coupling members have stainless steel keyway protectors or cement stops so that cementious material cast in the bore holes so as to stabilize the coupling members do not fill the keyways. After the cementious material has set, the space between bore holes up to the keyway slots is excavated including …