Hazardous Property Sold at Auction - Any recourse???

[Account Closed]

I bought a property from a sheriff's sale only to find that the property has an oil tank leak from an above ground storage tank in the basement.  It was never disclosed that there were environmental issues during the auction.  I only learned of this after the purchase. The next door neighbor told me that this likely happened as a result of the flood from Hurricane Sandy. The oil tank appears to have been decommissioned at some point since the home has been converted to gas but there was obviously a spill on the concrete floor that lingered around for 5-6 years.  The odor is VERY strong and has small piles of mud scattered throughout. I'm not sure what the implication is to clean up this mess and the potential nightmare that might ensue based on some of the horror stories I've read about. The deed is not conveyed to me since it's taking 6-8 weeks to process so I'm technically not the owner yet. I definitely don't want to inherit this potential disaster especially since this hazard was never disclosed upfront.  Is it even legal to sell a contaminated home at an auction without any disclosure?? Any thoughts on how I can get out of this nightmare??