leachate

noun

1. a solution resulting from leaching, as of soluble constituents from soil, landfill, etc., by downward percolating ground water: Leachates in the town’s water supply have been traced to a chemical-waste dump.

noun

1. water that carries salts dissolved out of materials through which it has percolated, esp polluted water from a refuse tip

n.1920, from leach + -ate (1).