Get one of Liquatex's oil-only sweep to deal with the remnants of oil sheen left on the water after a clean-up.  The sweeps are designed as a length of absorbent attached to a nylon strap.

Folded Oil and Fuel Sweep

Liquatex’ Oil and Fuel Sweep is designed to catch oil-sheens that linger behind on water. Features a sturdy constructed length of absorbent securely attached to a nylon strap. Great as the final clean up step after an oil spill.