Asphalt is a combination of gravel and tar and is commonly used to cover driveways. Asphalt sees a variety of stains, especially those caused by leaking fluids from vehicles. Gas and oil are two common items that stain asphalt driveways. Not only will gas and oil stain the asphalt, they will also eat away at the driveway surface. Gas and oil should be removed from the asphalt as soon as possible to prevent further damage to your driveway.
Cover the oil and gas stains with clumping cat litter. The cat litter must cover the gas and oil completely. Allow the cat litter to sit on the stains for several hours.
Remove the cat litter by sweeping it into a dustpan with a broom. The cat litter will have acted as an absorbent and soaked up the gas and oil residue. Discard the cat litter into a garbage bag.
Pull on a pair of rubber gloves to prevent skin irritation. Fill a bucket with one gallon of water. Add one-half cup of trisodium phosphate to the water and mix with a wooden spoon.
Saturate the work end of a long-handled scrub brush in the mixture. Scrub the gas and oil stains vigorously with the brush. Continue saturating the brush in the mixture and scrubbing the asphalt until the gas and oil stains are no longer visible.
Rinse the asphalt driveway clean with a water hose. Repeat the process if needed.
Trisodium phosphate (TSP) is a heavy-duty cleaner, degreaser and mould killer that is available at home improvement centres and department stores.
To dispose of TSP, turn on your sink's faucet and allow cool water to run for several seconds. Slowly pour the TSP down the drain. Allow the water to continue to run for several seconds after all the TSP has gone down the drain. When the allotted time has passed, turn off the water.