SO EXACTLY WHAT ARE WE DOING, AND WHY ARE WE DOING IT?
Essential Problem
In 2017, there were one million active oil and gas wells in the United States.1 When a well reaches the end of its productive life, or if it fails to find economic quantities of oil or gas, the well operator is required by regulators to remove all equipment and plug the well to prevent leaks.2 Usually, cement is pumped into the well to fill at least the top and bottom portions of the well and any parts where oil, gas, or water may leak into or out of the well. This generally prevents contamination of groundwater and leaks at the surface. State or federal regulators define specific plugging procedures depending on the local conditions and risks, and may monitor the plugging operation.
However, there are many cases in which wells are not properly plugged before being abandoned, especially if the well operator goes bankrupt, leaving its wells “orphaned”.3 This is more common when oil prices fall rapidly, making many wells uneconomical, as in the 1980s oil glut, the 2008 financial crisis, and the 2014 downturn.
In the late 1980s, the U.S. Environmental Protection Agency estimated that 200,000 of 1.2 million abandoned wells may not have been properly plugged.4 Since then, tens of thousands of orphaned wells have been plugged by state and federal regulators, as well as some voluntary industry programs. These efforts are ongoing, and many orphaned wells have yet to be properly plugged. The exact number is not known: some 3.7 million wells have been drilled in the U.S. since 1859,6 and their history is not always well documented. Older wells, especially those drilled before the 1950s, are particularly likely to have been improperly abandoned and poorly documented.
Risks to Groundwater, Air, and the Surface Environment
Orphaned wells are often abandoned without any plugging or cleanup, but even plugged wells may leak, especially those plugged in the past, when plugging procedures were less rigorous and used less durable materials. Unplugged or poorly plugged wells may affect:
- Groundwater – old wells may have degraded well casing or cement that can allow oil, gas, or salty water to leak into freshwater aquifers. An assessment of 185 groundwater contamination incidents in Ohio from 1983 to 2007 found 41 incidents caused by leakage from orphaned wells, compared to 113 incidents caused during drilling and production.7
- Methane emissions – a study of 138 abandoned wells in Wyoming, Colorado, Utah, and Ohio found that over 40% of unplugged wells leaked methane, compared to less than 1% of plugged wells. This study estimated that abandoned wells account for 2-4% of the methane emissions from oil and gas activity.8
- The surface environment – orphaned sites may still have old equipment, contaminated soil from small spills, and other waste at the surface. In some unplugged or poorly plugged wells, oil, gas, drilling mud, or salty water can rise up the well and spill at the ground surface or, in the case of offshore wells, into open water.
Hydraulic fracturing uses the high-pressure injection of fluids into oil- or gas-bearing rocks to fracture them and allow oil and/or gas to flow out. The increased pressure in the rocks during this process can push oil or salty water up nearby unidentified or improperly plugged abandoned wells. In one of the more extreme cases of this, the U.S. Environmental Protection Agency cited an abandoned well in Tioga county, Pennsylvania, that produced a 30-foot geyser of brine for more than a week as a result of hydraulic fracturing of a nearby well.10 In addition to these fluids contaminating soil and potentially reaching groundwater, the unexpected pressure release caused by this fluid escape reduces the effectiveness of the hydraulic fracturing operation, so there are both environmental and economic incentives to identify and plug wells near a planned hydraulic fracturing operation.
The growing concern that some of the oil and gas wells in Colorado have been abandoned and are causing safety and health concerns in the communities surrounding them. The solution so far has been sealing up the wells and cleaning up the surrounding area. The problem that the students have been given to solve is to find a use for the well other then sealing it and it in some way must benefit the community.
Essential Learning’s:
Understanding and using Colorado’s geology to determine alternative uses of orphan gas and oil wells. By developing solutions to this growing issue these solutions can be used in other locations experiencing this problem. .
Problem addressed:
Using prior knowledge of the structural geology of Colorado specifically the DJ basin redevelop orphan wells in ways that will benefit the local community. The solutions to these problems will be built around the student's understanding/recognition of the sub-surface geologic structures that exist in Colorado and how these can be exploited to benefit communities that surround them.
Lenses
The students will be solving the problem through the expertise of 4 trans-disciplinary lenses: Geologist (1), Policy Specialist(1),
Project Manager (1), and Environmental Specialist (1)
Geologist: An expert on the understanding of the history of our planet. The better they understand Earth’s history the better the ability to predict events that might influence future events. These experts will explain what kind of geologic processes occurred at selected locations in Colorado and why this geology was used to select these locations. They will need to use proper scientific vocabulary in your presentations, for example; Explain how the different structures represented on the map (anticlines, synclines, etc.) contribute to possible deposits and storage of helium.
Policy Specialist: An expert that will be able to bridge communications between private businesses and members of different government bodies. They will be responsible for lobbying or coordinating with government. They will be responsible for conducting research, understanding government policy, educating team members on policy standards, and leading proposals or program development related to policy. They will need to have an in-depth knowledge of the policy they are meant to represent or work on, and be familiar with how government operates within their jurisdiction.
Project Manager: An expert on the cost of a project. This expert will be developing possible costs involved in the solution. These costs might include; drilling costs, set up costs, tear down costs, permit costs, cleanup costs, EPA costs, etc. This expert will be responsible for presenting cost/business proposal.
Environmental Specialist: A expert that works to protect the natural world from pollution and other threats. This expert will be researching the possible environmental impacts from the groups solution working very closely with the policy specialist making sure that all possible environmental issues are addressed and then addressing each impact with all possible solutions. They will be relaying costs associated with solution to the project manager