Orphan wells: the government and oil and gas industry know they’re out there, but where exactly they are can be a perplexing question.

Orphan wells, as the name suggests, are wells without an owner. Over the years, perhaps thousands of them have not just merely been neglected by operators that have walked away. They’ve also been lost to history.

“These are the wells that don't exist on maps,” said Andrew Govert, manager of the Department of Energy’s Undocumented Orphaned Wells Research Program. “In these states where we've been drilling oil and gas wells in excess of a hundred years, there's a lot of wells that were drilled before there was ever any record keeping and before records were even well kept.”

Abandoned wells can pose a variety of problems. They can be a threat to the environment, not only emitting potent greenhouse gases such as methane, but also contributing to groundwater and surface water contamination amongst other safety hazards.

Far too many wells across the country haven’t been properly cared for or even acknowledged, panelists said at the 2023 International Meeting for Applied Geoscience & Energy (IMAGE) in August.

The Interstate Oil and Gas Compact Commission estimates the number of undocumented orphan wells to be between 310,000 and 800,000, said Kimbra Davis, director of the Department of the Interior’s Orphaned Wells Program Office.

To deal with them, in 2021 the federal government approved a $4.7 billion budget for the Orphaned Wells Program to support plugging and abandonment operations across federal, tribal, state and private lands.

“We have $4.3 billion going for the state program; tribal grants are up to $150 million and the federal program is $250 million with partners,” Davis said.

Since the Bipartisan Infrastructure Act passed in November of 2021, “we released guidance with state initial grants and awarded $560 million to 22 states that received $25 million each, and two states that received $5 million each,” she said.

But such wells are good at hiding in plain sight.

Davis speaking
Kimbra Davis of the Department of the Interior (left) and Andrew Govert of the Department of Energy (right) taking questions during their “Orphaned and Abandoned Well Identification and Characterization Update” Panel at IMAGE Aug. 31. (Source: Hart Energy)

Scavenger hunt

In many respects, even with funding to remediate abandoned wells, there’s a scavenger hunt quality to tracking them down.

While the increase in funds devoted to the remediation of orphan wells has led to 4,000 wells plugged so far, the task of finding undocumented orphan wells remains daunting.

Various methods have been employed to locate the wells, but there is “no silver bullet,” Govert told the audience.

Magnetic surveys, for instance, can be challenged by steep terrain or tall vegetation. They also fail if the well casings have been removed. During World War II, for instance, approximately 15,000 well casings were salvaged for their metal.

Hunting for the wells by detecting emissions is also tricky. Emissions tend to be highly transient and methane measurements fail when the well is not emitting.

Even aerial and satellite photos are often obstructed by vegetation or construction. The historical record is likewise hit or miss, as documentation can be incomplete or inaccurate.

“There's no one technology that's going to find these things perfectly,” Govert said. “And so the approach we're taking is that the best idea is to layer as many different types of data as you possibly can over an area.”

Govert presenting
Andrew Govert presenting during IMAGE 2023. (Source: Hart Energy)

Using pieces of information from each of those possible layers and their relative relationships helps to “build out your best estimate of where these things are and which ones might be the biggest risk,” he said.

Drone technology offers a possible solution to identify orphaned wells, with fixed-wing drones being a relatively inexpensive option to cover large areas using magnetometers; laser imaging, detection and ranging, or LIDAR; and high-resolution photography.

AI plays detective

Newer technology, such as machine learning models, has also shown impressive results in fusing data from different sources, such as historical texts and images.

Taking the approach of using two data sources—compared to just a methane sensor—increases the accuracy of the model by a wide margin, Govert said.

Ultimately, with the help of AI, Govert and the Department of Energy hope to develop a free, open-source and optimization-based well plugging decision-support program to aid state regulators and others in planning and managing efficient and impactful plugging and abandonment campaigns.

“We can use AI for more than just looking at map data,” Govert said. “The other big effort that we're putting into is we want to pull data from different well records, production records, scout reports, those kinds of bits of information.”

The prospective program will aid in selecting and grouping wells for plugging, deploying and scheduling plugging and abandonment resources. The program will also identify regions of interest and allocate budgets between plugging and detection.

“We're really interested in using things like ChatGPT technology to extract the information that we're interested in, because there's never going to be enough people to go through all those records and pull out the information that we want,” Govert said.

The Department of Energy is also teaming with the U.S. Geological Survey and the Department of the Interior on the effort, “trying to make this as integrated as possible so that everybody has as much access as we can get to it.”