Methane Venting at Cold Heavy Oil Production with Sand (CHOPS) Facilities Is Significantly Underreported and Led by High-Emitting Wells with Low or Negative Value

Cold Heavy Oil Production with or without Sand, CHOP(S),
facilities
produce a significant portion of Canada’s conventional oil.
Methane venting from single-well CHOPS facilities in Saskatchewan,
Canada was measured (i) using Bridger Photonics’ airborne Gas
Mapping LiDAR (GML) at 962 sites and (ii) on-site using an optical
mass flux meter (VentX), ultrasonic flow meter, and QOGI camera at
11 sites. The strong correlation between ground measurements and airborne
GML supported subsequent detailed analysis of the aerial data and
to our knowledge is the first study to directly test the ability of
airplane surveys to accurately reproduce mean emission rates of unsteady
sources. Actual methane venting was found to be nearly four times
greater than the industry-reported levels used in emission inventories,
with ∼80% of all emissions attributed to casing gas venting.
Further analysis of site-total emissions revealed potential gaps in
regulations, with 14% of sites appearing to exceed regulated limits
while accounting for 61% of measured methane emissions. Finally, the
concept of marginal wells was adapted to consider the inferred cost
of methane emissions under current carbon pricing. Results suggest
that almost a third of all methane is emitted from environmentally
marginal wells, where the inferred methane cost negates the value
of the oil produced. Overall, the present results illustrate the importance
of independent monitoring, reporting, and verification (MRV) to ensure
accuracy in reporting and regulatory compliance, and to ensure mitigation
targets are not foiled by a collection of disproportionately high-emitting
sites.