Put the trash in either asphalt or concrete. Lets see - what materials have been proposed for concrete? Ground up car bumpers, waste carpet fibers, foundry sand, and on and on. But when it comes to the raw materials, such as cement and aggregate - the same people proposing waste into concrete get upset that we would contaminate the "pure" components that go into the concrete. One good example - use of recycled process water for ready mix. Experts say: Water must be "clean, free of contaminants and preferably drinkable." Has this sentiment toward material perfection changed? I would like to know...

Posted By : Roy Keck Posted On : 2/18/2009 8:59:35 AM