The EPA generally does not regulate private drinking wells. However, it is still vital that anybody who has a private drinking well ensure that it is constructed appropriately and in a manner that the drinking water is safe.
However, states do have well codes that parties need to generally be aware of when dealing with these issues. For those who are looking for information relative to state codes, it is vital that you conduct the appropriate research.
This might mean as well that you talk to a lawyer who is licensed and competent to practice law in your state. You also want a lawyer who has a familiarity with the state well codes in your jurisdiction.
Certainly if a well is not private and is for public consumption, the laws can get particularly more cumbersome.