I believe the old basement walls are just in too bad of shape or its ground water coming up from below.

.), but it is quite another thing to prevent it from permeating up through the ground.Even a sump pump will be of marginal use, as you would have to pump off the first few feet of the ground water that will be immediately replaced by new water via gravity.I have building like this, and it ain't fun. 

The restrictions can range from not using groundwater, to not digging dirt, limiting the use to the current use, maintaining the cap that covers the contamination such as parking lot or building foundation. there also may be certain periodic inspection and reporting obligations. the particular restrictions will be recorded and you can see them in the title work.   

You're not likely to make a profit if you have to do that.If it's on city water, then if there's a problem, the city has to solve it.With all that being said, there are some places where there's lots of groundwater, and wells are not considered as risky.If you're looking at a park with well water, check out: Pumps and well house to make sure all is in good working order; What the well capacity is?

The contaminants do not degrade quickly and sink into the groundwater.

The day AFTER the sale he searched Prothy and found out that in the 1930s, this place was a gas station and the original steel USTs were leaking into the ground water and aquafer and causing alleged medical issues for the surround neighbors who had filed a lawsuit. 

Once you are in the chain of title, even for one minute, you are 100% liable for the cost of cleaning-up soil and/or groundwater contamination unless you had a proper Phase I performed.

Also, there is a ground water contamination addendum attach lets me know it is bad I had to sign off on?

Typical issues with basements relate to gutters failing, grading being toward the structure or flat (surface water doesn't flow away from the building), grading funneling offsite water to the building, or ground water being high enough that it is against the foundation.

Of course right about the time we listed the area we were in was listed as a toxic area that had elements in the ground water causing cancer (just the sort of news you want when you list your home for sale!!)