Continuous measurements reveal wind and temperature affect orphan well methane emissions on the Kevin-Sunburst Dome, Montana

Science of the Total Environment
By: , and 

Links

Abstract

Fifteen leaking orphan wells on the Kevin-Sunburst Dome in northern Montana had emission rates that were affected by surface winds and diurnal temperature swings based on continuous monitoring data. Some wells showed correlating spikes in emissions when temperatures changed or wind speed increased while others demonstrated independent flow behavior despite being drilled into the same reservoir and located only a few hundred meters apart. Time-weighted mean methane emission rates ranged from non-detectable levels up to 2.7 kg/h in their as-discovered conditions, with leaking wells averaging 211 g/h. Emissions were measured continuously for up to 452 h per well during monitoring, revealing that leak rates can fluctuate by an order of magnitude within hours. Fluctuations in emission rates often synchronized between wells with overlapping emission measurement intervals, suggesting weather conditions, such as temperature and wind, affect emission rates (up to a factor of 4) with the most relevant factor being the effect of wind on wells with open holes. Additionally, this study presents the first methane emissions measured from an orphan well in two distinct conditions: as initially discovered (closed leaking valve, 2.7 kg/h) and again under unrestricted flow conditions (open valve, 11.8 kg/h), illustrating the maximum unobstructed leak rate and quantifying the constraints restricted leaking wells can have on emissions compared to open holes.

Suggested Citation

Gianoutsos, N.J., Haase, K.B., Birdwell, J.E., Hofmann, M.H., and Shuck, C.E., 2026, Continuous measurements reveal wind and temperature affect orphan well methane emissions on the Kevin-Sunburst Dome, Montana: Science of the Total Environment, v. 1020, 181577, 12 p., https://doi.org/10.1016/j.scitotenv.2026.181577.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Continuous measurements reveal wind and temperature affect orphan well methane emissions on the Kevin-Sunburst Dome, Montana
Series title Science of the Total Environment
DOI 10.1016/j.scitotenv.2026.181577
Volume 1020
Year Published 2026
Language English
Publisher Elsevier
Contributing office(s) Central Energy Resources Science Center
Description 181577, 12 p.
Country United States
State Montana
Other Geospatial Kevin-Sunburst Dome
Additional publication details