BARNSTABLE, Mass. — A judge is weighing whether to impose a temporary ban on spraying herbicides beneath overhead power lines in parts of Cape Cod.Three property owners are suing electric utility Eversource and have asked for a temporary restraining order until the lawsuit is resolved.They argue that the spraying violates state law prohibiting spraying within 100 feet of a public water supply, saying an aquifer that provides drinking water to Cape homes and businesses lies less than 100 feet from the surface and could be contaminated.