Method of sealing soil and other materials against the leakage of liquids and gases

Claim 1

A method of sealing an area of soil or other granular material against the seepage of a liquid or a gas, comprising laying into the soil a first, lowermost layer of strips made of an impermeable, thin sheet material in substantially parallel, non-contiguous alignment and with a gap remaining between each two adjacent edges, such laying taking place at a predetermined distance beneath the soil surface; laying a second layer of substantially parallel, non-contiguous strips of impermeable sheeting above the lowermost layer at a shorter distance from the soil surface, separated from the lowermost layer by a layer of soil, the alignment of the said individual strips being substantially parallel with those of the lowermost layer but positioned in a staggered arrangement, the central axes of the strips of the second layer lying substantially perpendicularly above the central axes of the gaps between two strips immediately below; the width of said strips being substantially greater than both the widths of said gaps and the distance between said first and second layers.

Claim 2

A method of sealing an area of soil or other granular material against the seepage of a liquid or a gas, comprising laying into the soil a first, lowermost layer of strips made of an impermeable, thin sheet material in substantially parallel, non-contiguous alignment and with a gap remaining between each two adjacent edges, such laying taking place at a predetermined distance beneath the soil surface; laying a second layer of substantially parallel, non-contiguous strips of impermeable sheeting above the lowermost layer at a shorter distance from the soil surface, separated from the lowermost layer by a layer of soil, the alignment of the said individual strips being substantially parallel with those of the lowermost layer but positioned in a staggered arrangement, the central axes of the strips of the second layer lying substantially perpendicularly above the central axes of the gaps between two strips immediately below; the width of said strips being substantially greater than both the widths of said gaps and the distance between said first and second layers.

Claim 4

A method of sealing a soil area against the seepage of a liquid as defined in any of claims 1 or 3, wherein each strip is laid underground by dragging through the soil, at a predetermined depth, a hollow cutting blade having an interior chamber and a leading cutting edge, said chamber containing a supply of said thin pre-formed strip material, and feeding said strip material from said interior chamber into the soil from the rear of said blade as said blade cuts through the soil.

Claim 5

A method of sealing a soil area against the seepage of a liquid as defined in any of claims 1 or 3, wherein the parallel strips constituting any of the layers are laid flat in one continuous plane.

Claim 6

A method of sealing a soil area against the seepage of a liquid as defined in any of claims 1 or 3, wherein each strip is laid in V-section so as to form a complete layer in wave form, with a gap running along the crest of each wave.

Claim 7

A method of sealing a soil area against the seepage of a liquid as defined in any of claims 1 or 3, further comprising laying drainage means in the gaps between adjoining strips of at least one layer.

Claim 8

A device for the sealing of soil against the seapage of liquid therethrough, comprising: a first, lowermost layer of soil; a first, lowermost layer of strips of an impermeable, thin film material in substantially parallel, non-contiguous alignment and with a gap remaining between each two adjacent edges of adjacent strips, said lowermost layer of strips overlying said lowermost layer of soil; a second layer of soil overlying said first, lowermost layer of strips; a second layer of substantially parallel, non-contiguous strips of impermeable film lying above said second layer of soil, the alignment of said individual strips of said second layer of strips being substantially parallel with those of the lowermost layer of strips, but positioned in a staggered arrangement, the central axes of the strips of the second layer of strips lying substantially perpendicularly above the central axes of the gaps between two strips lying below the lowermost layer of strips, and a third layer of soil overlying said second layer of strips of impermeable film material; the widths of said strips being substantially greater than both the widths of said gaps and the thickness of said second layer of soil.

Claim 9

A device for the sealing of soil against the seapage of liquid therethrough, comprising: a first, lowermost layer of soil; a first, lowermost layer of strips of an impermeable, thin film material in substantially parallel, non-contiguous alignment and with a gap remaining between each two adjacent edges of adjacent strips, said lowermost layer of strips overlying said lowermost layer of soil; a second layer of soil overlying said first, lowermost layer of strips; a second layer of substantially parallel, non-contiguous strips of impermeable film lying above said second layer of soil, the alignment of said individual strips of said second layer of strips being substantially parallel with those of the lowermost layer of strips, but positioned in a staggered arrangement, the central axes of the strips of the second layer of strips lying substantially perpendicularly above the central axes of the gaps between two strips lying below the lowermost layer of strips, and a third layer of soil overlying said second layer of strips of impermeable film material; the widths of said strips being substantially greater than both the widths of said gaps and the thickness of said second layer of soil.

Claim 12

A device in accordance with either of claims 7 or 8, further comprising drainage means in the gaps between adjoining strips of at least one layer of strips.