Refers to a well that meets any of the following criteria: 

1. construction as terminated prior to completion of the well,
2. the well owner has notified the local Board of Health that use of the well has, after extended use, been permanently discontinued,
3. the well has been out of service for at least three years,
4. the well is a potential hazard to public health or safety and the situation cannot be corrected,
5. the well is in such a state of disrepair that its continued use is impractical, or
6. the well has the potential for transmitting contaminants from the land surface into an aquifer or from one aquifer to another and the situation cannot be corrected.