If the sample taken from inside the house then the sodium is likely from the water softening/treatment system if one is present.

What a minute - how could the owners not know if they have a water softening system in the house?!?! Unless they didn't actually live there? But still - they bought it at some point and should know... (kind of scary if they don't -- like what else are they not aware of if they're not aware of something as basic as their water system -- yikes!)

If it is not a water softener there are natural sources. Early settlers would look for what were commonly called 'salt licks' and use them as a source for salt. New York does have them. Salt licks are where the water comes to the surface and evaporates. You might check in the area to see if there used to be any "health spas". Not certain which type of mineral water Saratoga Springs has but it is one that comes to my mind immediately.

Talk to a local well/water company. They can answer all your questions. If you buy the house you will need their services at some point.

Agree with shivece. Get the proper information from a well water equipment company. Well water is tested by an environmental company in my area of S Fl and the well equipment is checked by a water softening company that has a good reputation (not all of them do). Each well in my area needs different equipment depending on the tests from the well water. Some are more sulfer and others have more iron. I don't know tour area so you need someone that can give you accurate info about the equipment you have and the equipment you need for the well water results you have now.

There was no bacteria in the well— the story they have is the woman who lives there is an elderly widow and isn’t aware of the systems as the deceased husband was the caretaker. But it’s been over a year so I don’t think that it’s a water softener if no one added salt !

It's very possible that either there is no equipment and you need some for the water you have - or that there is equipment of which the owner is unaware since she hasn't had anyone there for over a year. It's still worth checking out. I have seen people live on well water that needed a system and they never put one in at all. As a result the pipes were completely discolored and damaged by the sheer amount of iron in the water as an example. It may not be the same with the house you are buying, but check it out please.

I see no evidence of a water softening system.

Your best course of action is to contact a local, not national brand, water treatment company. The owner will have full understanding of the local water composition.

I know that when we lived in Dutchess County we had to add a softening system. We had very hard water. This was common to the area. Otherwise, our pipes would have been eaten up with iron and corrosion. It's not healthy water without filtering.

Given the high level of sodium, I would want to find out the depth of my well, too. Is it so shallow that surface water is getting into it? That's something I would find out before I closed. What is the well depth? The deeper the better. Once again, your local water purification company can give you a good overview of the area conditions.