Unearthing Pennsylvania’s legacy of orphan and abandoned wells

What are orphan and abandoned wells?

Every state defines them a little differently. In Pennsylvania:

Orphan wells: These are oil and gas wells left behind by their owners before 1985 and are no longer in service.
Abandoned wells: These are wells that haven’t produced in the past 12 months. While their equipment might be removed, they were never properly plugged.

These wells have not been plugged or cleaned up. They may still be polluting Pennsylvania’s air and water, harming people’s health, threatening property values, accelerating climate change, and hurting the local economy. They are all over the Commonwealth and could be in building basements, farm fields, forests, waterways, and around homes. They may even be in your neighborhood. The total number of orphan and abandoned wells in Pennsylvania is unknown but is likely in the several hundreds of thousands — best guesses are 300,000 to 700,000.

The above map shows the known wells in Pennsylvania. However, this captures perhaps only 10% of the true orphan and abandoned well population in the Commonwealth. The purpose of this project is to help find and document additional orphan and abandoned wells.

Why should we care?

Orphan and abandoned wells put the safety of those who live nearby at risk. They can leak oil, gas, and other toxic chemicals into our air, soil, and water. Children who live, learn, and play near orphan and abandoned wells and their pollution are especially vulnerable to harm. These wells also are a significant source of harmful methane pollution.

By finding wells, additional funding can be leveraged to create good paying jobs with local well plugging companies, increase property values for the landowners, and return lands for potential new, economically beneficial uses.

The project

In collaboration with the Pennsylvania Department of Environmental Protection (DEP), the Department of Energy (DOE), McGill University, and Moms Clean Air Force, Environmental Defense Fund (EDF) has launched a project to locate and address these wells in Western Pennsylvania. To locate these wells in Pennsylvania, we will use drone-mounted magnetometers and advanced methane detection technologies.

Focus areas

These locations were provided to us based on current and historical data, as areas with a high probability of having undocumented orphan and abandoned wells. The project will kick off in three counties in Northwestern Pennsylvania beginning in mid-October and running through the end of November (after the leaves are down and before rifle hunting season). We anticipate the drone surveys to take less than one week in each county. There will also be on the ground field work the following spring/summer to verify the location of wells detected and to measure methane leak rates from a subset of these wells. With additional funding, we expect to begin this work in several areas of Southwestern Pennsylvania in 2025. 

Northwestern Pennsylvania survey areas:

• Clarion County: 8.5 square miles near St. Petersburg (view map)
• Venango County: 7 square miles south of President (view map)
• McKean County: 4.3 square miles south of Mount Jewett (view map)

Finding and addressing the wells

To address this problem, which is nationwide, this project in Pennsylvania is piloting techniques that the Department of Energy’s Orphan Well Program is developing to find these wells quickly and efficiently so that they can be properly plugged and abandoned. Our approach involves:

1. Map Analysis: Identifying regions with the highest probability of orphan wells.
2. Aeromagnetic Surveys: Using drones to detect magnetic signatures and methane emissions.
3. On-Ground Surveys: Verifying well locations and measuring methane emissions.

Drone technology

The drone, equipped with sensors, will be flying 100 feet above the ground, collecting magnetic and methane gas information. With these types of sensors, there is no private information collected, such as pictures or video of people or buildings, in the areas being flown. With the information gathered by these sensors, DEP staff can predict where suspected oil/gas wells can be found. The drone will make a buzzing noise, similar to a gas lawnmower, but won't be distracting. It will fly over a location several times, so it isn't unusual if you see it flying in the same area for a few minutes. As safety is a priority, at all times, there is a drone pilot, who is supported by crew members. They all work together to make sure that the drone avoids obstacles (birds, tall trees, and other planes). The drone will always remain in sight of the crew, and at no times is it allowed to fly unattended.

What happens next?

If it is determined that the well is an emergency, DEP will address it as soon as possible. DEP will evaluate the risk of each well found and add it to the plugging schedule. More than 200 wells were plugged in 2023-24. Federal funding through the Infrastructure Investment and Jobs Act (IIJA) has the potential to provide ~ $400 million to plug and remediate Pennsylvania orphaned oil and gas wells through 2030. By finding and documenting additional wells, more federal funding (potentially billions in support) could be leveraged in the future. The status of well plugging and other detailed information regarding. IIJA plugging projects can be viewed at the DEP IIJA Dashboard at dep.pa.gov/IIJAOilGas.

Additionally, in response to a new state law, the DEP has established a grant program for accelerated plugging of orphan wells. By plugging these orphan and abandoned wells, we can create jobs, raise property values, cut pollution, tackle climate change, improve our health and create a brighter future for us all.

Abandoned and Orphan wells are a critical issue for Pennsylvania. It is our hope that this project creates a model for locating, mapping, and facilitating remediation of undocumented wells using advanced technologies. By doing so, we can work together to mitigate methane emissions and reduce the leakage of harmful chemicals into the environment, thereby protecting the health of our communities. This work also supports the economy of western Pennsylvania by raising property values where old wells are plugged, and creating family-sustaining jobs that will last decades given the scale of remediation work needed to overcome this problem.

 For more information, please email us at paw@edf.org.

Additional resources

• Download a printer-friendly brochure here
• Learn more about DEP’s abandoned well program here
• See the Department of Energy's CATALOG on orphaned wells here

Watch the webinar