Millions of orphaned oil wells are a ticking time bomb for the US

Oil and gas (O&G) activity in the US has grown exponentially in recent years. With the advent of more efficient extraction techniques such as fracking, the O&G industry has seen one of the largest increases in production and exports in the global O&G landscape. This growth, although relatively recent, is preceded by a period of U.S. O&G production stretching back to the 1980s. This frenetic activity in O&G extraction has left thousands of oil wells abandoned in the United States.

Two types of abandoned oil wells can be distinguished. On the one hand, abandoned wells are those that are known to the company that manages the well, but has decided to stop operating it and extract resources from the area. Orphan wells are those that have ceased to be producers and the companies that managed that well are in liquidation or are unknown. According to the United States Department of the Interior, orphan wells are extremely dangerous areas for the environment and can seriously affect the public health of the area by polluting the water and emitting harmful gases such as methane. These areas can even be affected by floods, earthquakes and explosions, thus affecting the wild ecosystem of the area. In the United States alone, the Environmental Protection Agency estimates that there may be approximately 4 million abandoned oil and gas wells in 27 states, more than 117,000 of which are considered orphan wells. The latter means that there is no company to manage and be responsible for the environmental impact that these wells can generate. Since these wells can be abandoned for several decades, in many cases it is very difficult to find them due to the vegetation in the area or due to problems inherent in the land on which the abandoned well is located. For example, in West Virginia it is estimated that there are thousands of orphan wells that are not yet documented, in addition to the at least 6,500 wells that are documented. In Texas, one of the states where much of North America’s oil activity is located, the Railroad Commission estimates there are about 8,500 inactive wells that have not yet been capped, although experts warn there are thousands which have not yet been documented. These data warn that orphan wells represent a very serious environmental and social risk, which may increase considerably in the coming years.

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Many of the wells that are now inactive date back to the decade of World War II and the decade of the 1980s. These wells were then covered with steel and cement. However, this material has begun to corrode due to the corrosive effects of the contaminated oil and water reserves still in the area. Some of the wells that have already been decommissioned and plugged again pose an environmental problem because the materials used were ineffective for plugging the well. One of the main causes of the resurgence of orphan wells that were already properly capped may be the fracking boom. Fracking uses wastewater to fracture the source rock. Wastewater could pressurize aquifers beneath old wells, leading to a well blowout and ruptured plugs. This reason, among others, warns that orphan wells should be considered a priority issue for companies and the United States government.

One of the main barriers that make it difficult for companies to manage orphan wells is the cost of operation. It is estimated that the costs of plugging an abandoned well can exceed $100,000, as high as $2 million if the well casing fails and must be recovered, and environmental cleanup and restructuring work must be performed in the area.

Columbia University estimates that the cost of capping 500,000 wells (about 15% of the estimated total in the United States) could exceed $24 billion. Although the cost is high, companies are the main cause of the potential environmental and social damage caused by orphan wells, so they must take responsibility for investing in managing this problem. However, many of these companies are unknown or have gone bankrupt. Therefore, it is the United States government, in many cases, that must pay attention to this problem.

As you might expect, orphan wells are a major environmental and public health hazard. The main damages to the environment are oil spills that can affect groundwater, as well as methane emissions, which are one of the most harmful effects of climate change. In terms of public health, orphan wells can affect recreation areas, cultural areas and community spaces very close to the population. According to the Environmental Defense Fund and McGill University, 4.6 million people live within half a mile of an abandoned well. Water pollution can lead to negative impacts on vegetation and wildlife on the land where orphan wells are located. By taking water samples, the San Antonio Testing Laboratory found that every liter of water tested had 0.05 milligrams of benzene, a component that oil has and is extremely carcinogenic. These data suggest that immediate action should be taken to reduce the number of orphan wells that are not covered or ineffective.

One of the state’s major investments was the Bipartisan Infrastructure Act, which allocated more than $4.7 billion to put the brakes on the problem. However, the cost of capping currently documented orphan wells significantly exceeds this amount.

In addition to the need for greater investment, it is important to consider the role of monitoring and tracking already covered orphan wells. The Interior Department recommends states monitor up to 5 percent of the wells they plug with federal funds, but few do. According to Dwayne Purvis, Principal Advisor at Purvis Energy Advisors, “we know that our cement is brittle, that the steel left in the hole can corrode, and that the interfaces between the steel, cement and rock can separate. We know that the risk of failure must increase with time.” New technologies such as drones or artificial intelligence can help improve the identification of orphan wells and their subsequent monitoring.

All in all, orphan wells may become one of the worst environmental nightmares for the United States in recent history. More research and investment in this area is essential to reduce the negative impact these wells can have on public health and the environment.

By Antonio Garcia for Oilprice.com

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