No matter how careful we are or how hard we try, eventually oil stains appear on driveways or sidewalks. Several commercial products have been designed to clean and degrease concrete floors, driveways, and sidewalks. Unfortunately, many of these products contain acid. And in California (and many other states), you must not allow the "dirty" water to flow into the storm drain. There are severe penalties for this. Here are some basic strategies for removing or lightening oil stains: Kitty litter … [Read more...]