Cleaning up the soilIndustries spend millions of dollars cleaning up hazardous waste. Just one 55-gallon drum of waste can contaminate a lot of soil and water. Although new regulations ban traditional waste going to landfills, it wasn't long ago that hazardous waste was routinely dumped in landfills and many manufacturing sites. Liquids and solvents can leak into the soil causing contamination. Cleanup costs are enormous and often prevent businesses from continuing normal operations. Numerous industries are faced with the challenge of cleaning up the soil. When the soil is contaminated, it can be mixed with lime which neutralizes the harmful elements. However, this method is not always successful. In most cases, the soil must be dug up and transported by truck to special landfills and incinerators. In addition to the high costs, transporting contaminated soil puts people at risk. Over the past decade, scientists have explored innovative alternatives to save money and improve safety. Overall there are more than one hundred new technologies in various stages of development. New technologies focus on treating contamination on-site versus established technologies where treatment is conducted off-site. Proponents argue that these new technologies will lead to more thorough cleaning at a fraction of the cost. Pollution-Eating Bacteria Pollution-eating bacteria are used to clean soil contaminated by petroleum waste. Researchers have successfully developed a bacterium that reduces the complexity of oils and gasoline. Soil Washing Another new method is soil washing. A cleaning solution has been developed that washes PCBs and oils from the soil. The solution penetrates the soil and collects PCBs at the base of the soil. PCBs can be separated from the solution and are incinerated. The solution can then be reused after the PCBs have been extracted. Bioremediation A natural soil bacterium was developed to clean groundwater and soil contaminated by chlorinated solvents such as those found in dry cleaning fluids. Test results show that this bacterium cleaned the water sufficiently to meet EPA drinking water standards. This process of using a natural bacterium to clean water is called bioremediation. Bioventilation/Vacuum ExtractionBioventilation stimulates the growth of pollution-eating microorganisms by drawing surface air down through contaminated soil. The surface of the ground is covered with a plastic sheet and a vacuum pump installed in a well under the ground sucks the surface air downwards.