How to Remove Oil Stains From Streets
- 1). Pour a 50/50 mix of kerosene and naphtha solvent into a metal container. Add about two ounces of dish detergent per gallon of kerosene/naphtha, gently stir the mixture and cover it. An old paint can will work well to contain and seal the mixture, provided that you've thoroughly cleaned the can beforehand. Wait until the hottest part of the day, stir the mixture and pour it over the stain. Continue adding the solvent mixture until the concrete becomes saturated and the solvent pools on the surface.
- 2). Cover the solvent puddle and oil stain with an old pot lid or paint can. This procedure will not only slow the rate of solvent evaporation, it will help contain heat and help the solvent work. A coating of flat black spray paint on the outside of your cover will allow it to absorb far more heat, to get things moving faster. Allow the cover to stand for an hour and check the stain.
- 3). Wipe the solvent and any oil away with a few old rags. Place them in a fireproof container, for later disposal at an authorized toxic-waste facility. Repeat steps one and two -- two to three more times. The hotter you get the solvent mixture, and the longer you let it sit, the better it will work. Just make sure that you never allow it to completely evaporate, or you'll just thin and spread the oil stain. Wipe the solvent and oil stain away.
- 4). Cover what's left of the stain with a one-inch-thick layer of kitty litter that contains baking soda -- and allow it to sit overnight. The solvent that has soaked into the concrete will eventually dissolve and displace the oil. The mixture will slowly sweat from the concrete and soak into the kitty litter. Dispose of the kitty litter in an appropriate manner.
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