TY - JOUR
T1 - Evaluating Methane Emissions From Decommissioned Unconventional Petroleum Wells in British Columbia, Canada
AU - Cahill, Aaron G.
AU - Joukar, Mohammad
AU - Sefat, Morteza
AU - van Geloven, Chelton
N1 - Funding Information:
This work was funded by BC OGRIS under project ES‐Wells‐2021‐02 and facilitated by a student in receivership of a James Watt Scholarships funded by Heriot Watt University. Expert advice and input to the project were provided by Mr. Jordan van Besouw of the British Columbia Energy Regulator and Mrs. Leah Davies of Imperial Oil who formed the advisory committee. Multiple well Industry Operators assisted and facilitated the research particularly in terms of field site access, which is duly acknowledged and greatly appreciated. The authors acknowledge that fieldwork in this project took place on the lands of the Treaty 8 First Nations.
Funding Information:
This work was funded by BC OGRIS under project ES-Wells-2021-02 and facilitated by a student in receivership of a James Watt Scholarships funded by Heriot Watt University. Expert advice and input to the project were provided by Mr. Jordan van Besouw of the British Columbia Energy Regulator and Mrs. Leah Davies of Imperial Oil who formed the advisory committee. Multiple well Industry Operators assisted and facilitated the research particularly in terms of field site access, which is duly acknowledged and greatly appreciated. The authors acknowledge that fieldwork in this project took place on the lands of the Treaty 8 First Nations.
Publisher Copyright:
© 2023. The Authors.
PY - 2023/12/28
Y1 - 2023/12/28
N2 - Hundreds of thousands of unconventional natural gas wells recently constructed across North America have transformed the global energy landscape and generated widespread concern relating to fugitive methane leakage. To date, no studies have evaluated the integrity of unconventional wells post-abandonment. Here, we evaluated emissions at nine decommissioned unconventional wells within the Montney region of British Columbia, Canada and found two exhibited co-emission of CH4 and CO2 from surrounding soils indicating integrity failure, releasing up to ∼2,000 kg of CO2-eq/yr into the atmosphere. A further three wells exhibited statistically significant anomalous CO2 fluxes of ∼500 kg/year from surficial soils around the well, likely associated with minor integrity failure and derived from near total soil-based aerobic oxidation of fugitive CH4. These findings suggest that more than half of decommissioned unconventional wells may generate emissions, however only relatively small contributions to GHG emissions result that are significantly mitigated through natural soils-based CH4 oxidation.
AB - Hundreds of thousands of unconventional natural gas wells recently constructed across North America have transformed the global energy landscape and generated widespread concern relating to fugitive methane leakage. To date, no studies have evaluated the integrity of unconventional wells post-abandonment. Here, we evaluated emissions at nine decommissioned unconventional wells within the Montney region of British Columbia, Canada and found two exhibited co-emission of CH4 and CO2 from surrounding soils indicating integrity failure, releasing up to ∼2,000 kg of CO2-eq/yr into the atmosphere. A further three wells exhibited statistically significant anomalous CO2 fluxes of ∼500 kg/year from surficial soils around the well, likely associated with minor integrity failure and derived from near total soil-based aerobic oxidation of fugitive CH4. These findings suggest that more than half of decommissioned unconventional wells may generate emissions, however only relatively small contributions to GHG emissions result that are significantly mitigated through natural soils-based CH4 oxidation.
KW - fugitive gas
KW - hydraulic fracturing
KW - integrity failure
KW - methane
UR - http://www.scopus.com/inward/record.url?scp=85180402436&partnerID=8YFLogxK
U2 - 10.1029/2023GL106496
DO - 10.1029/2023GL106496
M3 - Article
AN - SCOPUS:85180402436
SN - 0094-8276
VL - 50
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 24
M1 - e2023GL106496
ER -