Fugitive Methane Emissions

Methane is emitted from equipment almost all the time on oil or gas production sites. Some emissions are routine and expected, i.e., vented or combustion, while others are uncontrolled and unexpected, i.e., fugitives. Detecting location and mitigating fugitive emissions on oil and gas production sites has been identified as key to achieving climate goals. To help address this, this chapter describes methods that can be used to detect emissions and distinguish fugitive from vented or combustion emissions based on relative size, frequency, and duration of the emissions. The theory behind each quantification method is described, including survey methods with/without tracer gases, continuous monitors, and component level measurements. There is also a description of state-of-the-art instrumentation that includes relative detection limits, quantification limits, and associated uncertainty. The utility and efficacy of fugitive mitigation strategies are then reviewed, including LDAR requirements, changes to standard maintenance approaches, gas injection and on-site power generation.