According to the U.S. Department of the Interior (DOI), millions of Americans across the country live within just one mile from an abandoned coal mine or an orphaned oil and gas well. Legacy pollution sites pose significant environmental hazards and threaten public health and safety. They contaminate groundwater, emit noxious gasses like methane, litter the landscape with rusted and hazardous equipment, increase flooding and sinkhole risks, and harm wildlife.
What Happens to an Abandoned Oil Well?
An oil or gas well is plugged and abandoned when it reaches the end of its useful life or becomes a dry hole. The main goal is to guarantee that no leaks reach the surface and that formation fluid migration does not occur, even many years after the well has been abandoned. Safely plugging and abandoning these wells requires meticulous preparation and planning. This starts with ensuring the well site is safe for abandonment activities. Key assessments include evaluating safe access and egress, soil condition and stability, terrain contour, and the presence of plants or animals. Other considerations involve identifying potentially hazardous atmospheres near the well, managing traffic and movement, staging equipment, and addressing any other hazards.
The process of abandonment involves removing and salvaging wellbore casing, tubulars, and other equipment through techniques such as freepoint/ backoff, stretching, or cutting off tubulars at a specified depth using chemical cutting, explosives, hydraulic cutting, or pulling methods. Stuck tubulars above the cut are extracted with fishing tools, while those below the cut remain in the wellbore. Cement plugs are then installed and tested to prevent fluid migration between different formations, in compliance with federal and state regulations, which may vary. Finally, the upper casing is cut below grade, the well is capped, and the surface is reclaimed to match the surrounding environment, adhering to federal and state environmental regulations.
What are the Risks of Abandoned Wells?
Abandoned and orphaned wells are a serious problem in the United States due to the various environmental and safety risks that they pose to humans, infrastructure, and wildlife.
Dangerous Equipment
Abandoned oil and gas well equipment pose multiple risks, primarily due to their hazardous and deteriorating nature. Over time, rusted and corroded pipes, tanks, and other remnants can become unstable, risking collapse or breakage. This instability can lead to injuries for unsuspecting humans or animals that may come into contact with or explore these sites. The presence of rusting equipment also disrupts the landscape, impeding land rehabilitation efforts and adversely affecting the aesthetics and land usage.
Sinkhole Risks
Old oil and gas wells can cause sinkholes. When a well is abandoned and not properly plugged, groundwater can seep into the borehole, dissolving salt minerals such as halite or gypsum in the rock formation and creating underground voids. These voids can cause the ground above to collapse, creating dangerous sinkholes that can damage infrastructure and pose a risk to people's safety.
Risks to Wildlife
Abandoned oil and gas wells significantly threaten local wildlife and their habitats. These sites often become dangerous traps for animals, which can inadvertently fall into open wellbores or become entangled in discarded equipment. The contamination of soil and water sources with hazardous substances, such as hydrocarbons and heavy metals, further exacerbates the risks to surrounding ecosystems. Polluted water sources can lead to bioaccumulation of toxins in various species, affecting their health and reproductive abilities. Additionally, the emission of gasses like methane can interfere with local air quality, impacting both terrestrial and avian species. Habitat fragmentation and the presence of pollutants ultimately disrupt the delicate balance of ecosystems, leading to declines in biodiversity and impairing the natural behavior of wildlife.
Groundwater Contamination
Abandoned wells pose a significant risk to groundwater contamination as their casings and screens corrode over time, turning the wells into pathways for contaminants to move vertically through the boreholes. The extent to which an abandoned well can negatively impact groundwater quality depends on its original use, local geology, subsurface fluid characteristics, and construction type. Often, an abandoned well is merely covered with a board or a sheet of metal, sometimes welded in a futile attempt to prevent it from becoming a public hazard. However, such measures overlook the critical issue that an unplugged, abandoned well itself is a major threat to groundwater quality. If left unplugged, these wells jeopardize the area's water supplies and can indirectly lead to illness or death for those who consume the contaminated water.
Potential Release of Toxins & Air Pollution
Improperly plugged or decommissioned oil and gas wells are essentially open holes in the ground that can release harmful toxins like methane, arsenic, benzene, and hydrogen sulfide into the environment, even when they are no longer productive. These wells pose serious risks, including the potential for fires and explosions. Even a minor leak from a single well can have a significant impact over years or decades, contaminating soil and groundwater while contributing to air pollution.
One of the most alarming threats from orphaned oil wells is methane. This odorless gas can infiltrate homes, offices, schools, and other nearby buildings undetected, leading to severe health issues such as nausea, weakness, vomiting, and convulsions. In high concentrations, methane exposure can result in coma or even death, and it is highly explosive. Furthermore, these uncontrolled methane emissions contribute significantly to greenhouse gas levels in the atmosphere.
Abandoned Wells and The Bipartisan Infrastructure Law
The Bipartisan Infrastructure Law mandates the Secretary of the Interior to initiate programs for the inventory and proper closure of orphaned wells to eliminate environmental and public safety hazards. It allocates $4.7 billion for the plugging, remediation, and restoration of orphaned well sites across federal, Tribal, state, and private lands. An "orphaned well" refers to a well that is no longer used for authorized purposes such as production, injection, or monitoring. These wells have no identifiable operator, or the operator is incapable of plugging, remediating, and reclaiming the well site.
How Many Abandoned Wells are There in the U.S.?
According to the U.S. Government Accountability Office (GAO), there are an estimated 2-3 million abandoned oil and gas wells throughout the country. Research estimated that more than 117,000 of those are "orphaned," meaning that they are uncapped, unproductive, and with no responsible party identified to manage pollution and leakage risks.
Impact of Abandoned Wells on Real Estate
Abandoned wells can significantly affect land values and complicate property transactions. When evaluating properties, potential buyers and real estate professionals must consider the presence and condition of nearby abandoned wells. These wells often pose a hidden liability, with the potential to introduce contaminants to the soil and groundwater, leading to costly remediation efforts. In addition, the structural integrity of land surrounding abandoned wells may be compromised, increasing the risk of subsidence or sinkholes, which can lead to property damage and pose serious safety hazards.
During property due diligence, it is crucial to conduct thorough environmental assessments, such as Phase 1 reports, to identify any abandoned wells on or near the property. Proper documentation and remediation plans must be in place to address any discovered risks, ensuring the property's safety and compliance with environmental regulations. Ignoring these factors can lead to unforeseen expenses and legal liabilities, significantly impacting property value and marketability.
Property owners with long-abandoned wells and communities near old oil fields often face significant challenges when attempting to plug and decommission these orphaned wells. Many people impacted by these wells encounter numerous obstacles in the process. In summary, the presence of abandoned wells necessitates heightened vigilance in real estate transactions to safeguard investments and ensure public safety.
How to Find Abandoned Oil Wells
The DOI provides information about abandoned oil and gas wells and their location across the country. LandApp also provides the exact location of abandoned oil and gas wells across the country along with basic information about each well:
To assess your property's abandoned oil and gas well contamination risk, get a free property report on LandGate's map! Along with your specific property's oil and gas contamination risk, you'll find additional risk indexes to help you find out if your property is contaminated:
