When would the statute of limitations run out on an environmental claim?

We found out in November of 2008 that a factory in our area had been dumping waste water without filtration for years and chemicals have been found in wells around our area. We now cannot borrow money on our property ie: home equity loan / refinance /sell because we cannot get our property appraised because of the environmental impact. But we are still paying property tax on the full value of our property before the contamination was disclosed. Is there a statute of limitations ie: 1 year-7 years or whatever it may be that we need to act within a certain time to be able to recoop any loss property values that we have. Thank You.