A method of providing a dual waterproofing membrane assembly system for a structure, comprising the steps of:
- (a) forming at least one soil retention system having a first face and a second face, and wherein said first face faces compacted earth or soil;
- (b) securing at least one bentonite sheet waterproofing membrane layer membrane having a first face and a second face, to at least a portion of said at least one soil retention system, such that said first face of said at least one bentonite sheet waterproofing membrane layer is secured to at least a portion for said second face of said at least one soil retention system, and said at least one bentonite sheet waterproofing membrane layer is composed of a layer of a first material;
- (c) securing a layer of a second material composed of at least one waterproof sheet membrane layer having a first face and a second face, and having at least one layer of at least one adhesive on said second face of said at least one waterproof sheet membrane layer, to at least a portion of said at least one bentonite sheet waterproofing membrane layer, such that said first face of said at least one waterproof sheet membrane layer is secured to at least a portion of said second face of said at least one bentonite sheet waterproofing membrane layer, so as to form said dual waterproofing membrane assembly system for a structure;
- (d) wherein said first material is different than said second material;
- (e) wherein one of said at least one bentonite sheet waterproofing membrane, and said at least one waterproof sheet membrane layer extends along at least a portion of a vertical surface;
- and
- (f) wherein one of said at least one bentonite sheet waterproofing membrane, and said at least one waterproof sheet membrane layer extends along at least a portion of a horizontal surface.