Long ago I worked on boats taking supplies to offshore oil rigs. The oil companies would sometimes have boats searched with drug dogs.
Every boat I knew of had a big jar filled with water. If a new crew member came aboard and had marijuana he was required to add a pinch to the jar. The boats always knew when the dog would be at the dock. The big jar of marijuana tea would be poured into a mop bucket. More water was added along with soap. Then every deck would be mopped before we reached the docks.
Poor dog was useless, pot was everywhere!!!!