Abstract: A leak-testable, fluid-impervious membrane is formed as a laminate of a conductive mesh scrim between upper and lower insulative polymeric resin layers. The scrim is preferably a screen formed of a metallic wire, such as aluminum. The polymeric resin is preferably a thermoplastic, such as HDPE, PVC, or polypropylene. The membrane, when installed as a liner for a liquid receptacle or a roof, has an exposed surface on the upper insulative layer. When so installed, the membrane is testable for pinhole openings by an electrical leak survey method, in which an electrical potential is applied between the scrim and a conductive probe. The probe is passed over the exposed surface, so that the electrical potential creates an electric spark between the probe and the scrim at the location of a pinhole opening. An RF signal is generated in response to the spark, and an alarm is actuated in response to the RF signal.

Abstract: An axially slidable pipe boot provides a substantially gas-tight seal between a gas vent pipe and a flexible barrier sheet surrounding the pipe. In a first preferred embodiment, the slidable pipe boot comprises a tubular sealing member having an internal O-ring seal. The tubular member is dimensioned to fit around the exterior of the pipe with a compression fit of the O-ring providing a sealing engagement with the pipe. An annular flange on the lower end of the tubular member is sealingly attached to the barrier sheet. In a second preferred embodiment, upper and lower tubular sealing members are axially joined together by a hollow tubular sleeve that fits around the pipe. Each of the tubular members has an internal O-ring seal that engages the exterior of the pipe with a substantially gas-tight compression fit. The lower tubular member has an annular flange that is sealingly attached to the flexible sheet.

Abstract: A rain-collection pad for ponds comprising a pan-shaped pad having a horizontal bottom and four vertical, contiguous side walls, said pad being adapted to float on the exposed surface of a pond and having a stiffening means attached to at least one wall.