Abstract: A mop assembly is provided for the continuous application of wax and cleaning fluids which utilizes a detachable, disposable plenum incorporated into a disposable sponge mop. The disposable plenum has a plurality of substantially uniformly-spaced openings which provide for a substantially uniform distribution of fluid entering into the sponge. The disposable mop also has a substantially impermeable backing layer which shields the mop head and other non-disposable parts from wax, cleaning fluid, and residue present in the sponge. The disposable mop eliminates the problems associated with clogging of the openings in the non-disposable plenums currently in use, and substantially reduces the amount and frequency of required cleaning of the mop head and other non-disposable parts.