Bomb jacks are often used in wells that produce little oil. Since it is more expensive to remove the oil than it earns, a well is often abandoned.
An abandoned well is a well that has been drilled and later abandoned, for a variety of reasons. Abandoned wells pose a health and safety risk worldwide and are a cause for concern, especially in suburban and aging communities that are shifting from using wells to municipal water supplies. Many regions have specific legislation regarding abandoned wells and how they should be treated, with the aim of reducing the risk of pollution and injuries related to empty wells.
An abandoned well can serve as a place of accumulation of pollutants, which includes materials leached from septic tanks.
The risk of injury is clear: someone could fall into an abandoned water well and not be able to get out. The fall could injure or kill someone, and unless help is provided quickly, the victim of the fall could die in the pit. Especially if an abandoned well is located in a remote area, it can take days to realize that someone has fallen into the well. Abandoned waterholes also pose a threat to wildlife for the same reason.
In the case of an abandoned water well, the well can serve as a place of accumulation of pollutants and release these pollutants into the natural environment. These pollutants can include materials leached from septic tanks, which can pose a threat to human health if they enter the water table through an abandoned well. Abandoned oil and gas wells can also serve as a source of pollution, and unexpected releases or flames of material can pose a safety and health risk.
If a well is being temporarily taken out of use, it can simply be capped. Capping involves covering the well so that the contents are not accessible. Ideally, the lid should be clearly labeled and routinely checked for any signs of intrusion or damage that could indicate the lid is about to break. Plugging is also not intended to be a permanent measure, and people can be penalized for not handling an abandoned well properly if they leave a well closed for too long.
If a well is actually being abandoned and will not be used again, it must be sealed. The purpose of sealing is to restore the conditions that existed in the ground before the well was drilled. Sealing is performed by a licensed well driller and typically requires a permit from any local authority that deals with well excavation and sealing. The sealing must be done carefully to avoid injury and properly seal the well so that problems with the abandoned well do not arise in the future.