New Method for Locating Abandoned Oil and Gas Wells is Tested in New York State
Guest blog by Natalia N. Romanzo, graduate student, Binghamton University, Binghamton, NY
Innovations in geospatial remote sensing technology developed by a research team at Binghamton University’s Geophysics and Remote Sensing Laboratory allow for improved detection of unplugged oil and gas wells. Implementing this technology would allow responsible agencies to more efficiently locate, and then plug, the 30,000+ undocumented oil and gas wells in New York State. Plugging these wells would help residents to assess risks of any wells on or near their property, improve air quality, and keep New York State on track to reaching its greenhouse gas emissions targets.
Dangers of Unplugged Orphan Oil and Gas Wells
In 2018, the United States Environmental Protection Agency (EPA) estimated that nationwide, there were 3.11 million abandoned oil and gas wells. Sixty-nine percent — or 2.15 million — of these wells are not even plugged. Many were drilled prior to the existence of state regulatory programs, subsequently abandoned by their original owners or operators over a century ago, and then left unplugged or poorly plugged. State and federal regulators are in the process of plugging these wells, but the process is slow; many are still unplugged today.
Unplugged or incorrectly plugged wells can leak methane into drinking water and the atmosphere. As a greenhouse gas, methane in the atmosphere is more than 80 times more effective at trapping heat than carbon dioxide, and, as such, becomes a driving mechanism of global warming. Methane has come under scrutiny by climate scientists and other concerned with the relationship between unconventional gas drilling (“fracking”) and the climate crisis.
Anthropogenic methane is the cause of a quarter of today’s global warming, and the oil and gas industry is a leading source of these emissions. Every year, oil and gas companies release an estimated 75 million metric tons of methane globally, an amount of gas sufficient to provide electricity for all of Africa twice over. Unplugged wells are often high emitters contributing to this energy waste. A study of almost 140 wells in Wyoming, Colorado, Utah, and Ohio found that more than 40% of unplugged wells leak methane, compared to less than 1% of plugged wells.
Unplugged, incorrectly plugged, as well as active wells can all leak methane. Methane-leaking wells are especially problematic when their locations are undocumented or unknown. Until they are located, undocumented wells that remain unplugged can continue to emit methane into the atmosphere and into drinking water. For example, in Pennsylvania, methane was detected in water samples at average concentrations six times higher in homes less than one kilometer from oil and gas wells. The potential negative impact of unplugged orphan oil and gas wells makes this a pressing environmental concern.
Of the more than 3 million problematic oil and gas wells nationwide, over 35,000 unplugged oil and gas wells may exist in New York State alone. Unplugged or improperly plugged wells that leak methane can pose direct threats to New York State residents, especially for people living nearby to these wells. Many New York State residents are unaware that they have an unplugged well on their property, and could be at risk of potential exposure to uncontrolled releases of gas or fluids from unplugged orphan wells. In one case in Rushville, New York, two dozen unplugged wells emitted methane at explosive levels. An unplugged well in Rome, New York discharged brine to the land surface for decade at a rate of 5 gallons per minute, killing an acre of wetland vegetation. If these wells had been located and assessed, property owners would be better informed and safer.
In addition to directly harming New York State residents and contributing to climate change, unplugged orphan wells also impact New York State’s ability to reach its 2030 emissions targets. New York State recently set ambitious statewide greenhouse gas emissions targets through the Climate Leadership and Community Protection Act to lower emissions by 85% by 2050. However, New York State has only reduced emissions 8% from 1990-2015 levels. If New York State is to reach its emissions targets, it must continue and improve its efforts to locate, assess, and ultimately plug all its orphan oil and gas wells.
Inaccurate Records and Inefficient Detection Methods
The New York State Department of Environmental Conservation (DEC) is responsible for task of mitigating and preventing damage caused by oil and gas wells. Unfortunately, flaws in record keeping have made it difficult to locate undocumented wells. The DEC began record keeping of oil and gas wells in 1983 and took on regulatory authority over wells drilled in the state after 1983. There are strict rules and regulations for plugging wells drilled after 1983, and wells drilled prior to 1983 must comply with applicable regulations. Nevertheless, many older wells are still unaccounted for. In their external review in 1994, staff estimated that 61,000 wells had been developed prior to 1983. However, the agency only has records on about 30,000 of them. Because accurate records do not exist for old wells, it is difficult to monitor, and even locate, them.
Click here for a full-screen view of FracTracker Alliance’s map of all known wells in New York State (data current as of October 2018, to be updated soon).
View map fullscreen | How FracTracker maps work
Despite inaccurate records, the DEC does try to locate, assess, and plug old wells using maps created by drilling companies in the late 1800s. A section of one such map can be seen in Figure 1. This map shows proposed oil and gas drilling sites in Cattaraugus County, New York in the late 1800s. It has been georeferenced using ArcGIS mapping software to assign present day coordinates to hand drawn features.
Figure 1. Georeferenced Lease Map, Cattaraugus County, New York
Unfortunately, these maps are not entirely reliable. Some wells may be incorrectly documented on a map as drilled when, in fact, they were merely proposed but never drilled; some wells may have been drilled but never marked on a map. Other wells may have been both marked on a map and drilled, but due to inaccurate survey technologies of the past, the location on the ground is incorrect. As a result, DEC staff are left searching on foot for wells that may or may not be there. Working with limited equipment, in dense brush, and over uneven terrain make the task of finding the abandoned wells even more problematic.
These traditional methods of detection, which include referencing lease maps and searching for wells in the field, are not only time consuming, but are also costly. Using traditional methods of well detection, between 1988 and 2009, the United States Bureau of Land Management spent $3.8 million and only successfully reclaimed 295 well sites. It is clear that on both the federal and state levels, traditional well detecting methods are expensive, cumbersome, and inefficient.
Drones Pave the Way for Oil and Gas Well Detection
Recent improvements in geospatial remote sensing technology have opened opportunities for more efficient well detection. Previously, the battery life of drones and the weight of magnetometers prevented the two technologies from being used together to locate oil and gas wells. Furthermore, because drones must be flown high enough to clear vegetative canopies, methane sensors attached to drones are too far away from the source to accurately detect the location of the well. Due to these technological barriers, the DEC and other environmental departments and agencies have had to rely on inefficient, traditional methods of well detection described above.
At Binghamton University’s Geophysics and Remote Sensing Laboratory, a research team headed by Professors Timothy de Smet and Alex Nikulin, along with graduate student Natalia Romanzo, and undergraduate students Samantha Wong, Judy Li, and Ethan Penner, is taking on the task of developing a more efficient method to locate oil and gas wells. The Binghamton University research team deployed drones equipped with magnetometers to demonstrate that a high-resolution, low-altitude magnetic survey can successfully locate unmarked well sites.
Oil and gas wells have a characteristic magnetic signal that is generated by vertical metal piping fixed in the ground, making them identifiable in a magnetic survey.
Figure 2a. Oil and Gas Well Detected at 40m AGL showing LiDAR Total Horizontal Derivative of the site.
The magnetic signal generated by a well is shown in red in Figure 2b. At 40 meters above ground level (AGL), tree canopies are cleared, while the magnetic anomaly of the well is distinguishable. This drone-based magnetometer method has shown promising results.
Figure 2b. Magnetic Anomaly of an Oil and Gas Well Detected at 40m AGL, showing total magnetic intensity of the site.
To further test remote sensing techniques, the Binghamton University research team worked with Charles Dietrich and Nathan Graber from the NYS DEC to compare the efficiency of different survey methods. Currently, researchers are conducting fieldwork to compare the efficiency of traditional methods of well detection, well detection via a magnetic ground survey, and well detection via a drone-based magnetic survey. This research is showing that using drones equipped with magnetometers is a more efficient way to survey a wide area where wells may be present.
Remote sensing techniques can allow the DEC to more efficiently locate, and then plug, the 30,000+ undocumented oil and gas wells in New York State. Using this new method of well detection, the DEC will be able to inform residents who have unplugged wells on their property, assess the risks of the wells, and plug harmful wells. Residents with wells on or near their property will benefit directly. In addition, and more broadly, New Yorkers will enjoy improved air quality while New York State will be more on track to reaching its emissions targets.
FracTracker thanks Natalia Romanzo for her guest blog contribution. We feel that this technology holds promise for communities impacted by drilling across the nation.
For answers to specific questions about the project, you can email Natalia directly at email@example.com.