The oil company overfilled the oil tank. It soaked into the concrete and was difficult to remove. The spill also caused a terrible smell as the vapors seeped into the the rooms adjacent and above the furnace room. we tried various cleaners and deodorants to no avail. I then bought a gallon of VaporRemed and sprayed on the spill according to the directions. Within an hour the odor of the oil spill disappeared. I sprayed down the spill every second day so that it would stay damp and allow the VaporRemed to keep on working on the spill. After 10 days there was no smell left but the stain was still there.
vapor remedIt got rid of the smell and the oil stain within a few days and stayed fresh long afterwards. I highly recommend this product.