Abstract: The barrier is waterproof, and is used to contain contaminated groundwater within an enclosure. Steel elements are pile driven, the elements having rolled-over edge forms (5,6) which interengage. Upon interengagement, an enclosed hole (90) is created which extends from top to bottom of the piled elements. A scraper (19) on the junior element (8) cleans dirt out of the hole as the junior is driven down alongside the adjacent senior element (7). The hole may be cleaned out by inserting a hose pipe to the bottom of the hole (90) and flushing through with water. Then, a sealant is injected into the hole, using an injection tube in the hole. The interengagement of the edge forms (5,6) of the elements is such that the hole formed by the interengagement is constrained to its nominal size and shape throughout the whole height of the barrier.

Abstract: The barrier is waterproof, and is used to contain contaminated groundwater within an enclosure. Steel elements, are pile driven, the elements having rolled-over edge forms (5,6) which interengage. Upon interengagement, an enclosed hole (90) is created which extends from top to bottom of the piled elements. A scraper (19) on the junior element (8) cleans dirt out of the hole as the junior is driven down alongside the adjacent senior element (7). The hole may be cleaned out by inserting a hose pipe to the bottom of the hole (90) and flushing through with water. Then, a sealant is injected into the hole, using an injection tube in the hole. The interengagement of the edge forms (5,8) of the elements is such that the hole formed by the interengagement is constrained to its nominal size and shape throughout the whole height of the barrier.