Land is placed on the CLR when scientific investigations have proven it to harbour harmful chemicals and other toxic materials
. In some cases, those materials must simply be contained within the perimeter of the property; in other cases, the contaminants can be removed. In the latter case, the property can be taken off of the register if it is shown to be completely free of contaminants. If you inadvertently buy land that is on the CLR, you may end up having to pay a lot of money to clean it up - or to contain it. Either way, it's one unpleasant surprise that you'd undoubtedly like to avoid.