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: 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.