New EU regulations are increasing the pressure on pipeline operators to quantify rather than only detect methane leakage from buried natural gas networks. While open-path technologies can locate surface emissions, they often struggle to determine emission rates—particularly when leakages occur below ground or in areas with strong biogenic activity.

To address this challenge, we developed a new flux measurement system that combines established geochemical methods with modern sensing and AI-based data analysis. The instrumentation employs tunable diode laser (TDL) spectroscopy capable of resolving the methane/ethane ratio, allowing reliable separation of thermogenic leakage signals from biogenic background sources.

The approach builds on experience from volcanic gas monitoring, where similar setups were operated under extreme natural conditions on Vulcano Island (Italy). Knowledge gained from these demanding environments guided the adaptation of the system for pipeline applications, which has now been tested under controlled leakage conditions at gas distribution network test facilities.

The presentation will include results from these controlled experiments, showing quantitative agreement between known release rates and measured fluxes, together with analyses of detection limits, accuracy, and reproducibility under variable soil and atmospheric conditions.

By combining the accumulation chamber technique—a proven method for quantifying diffuse gas fluxes—with AI-enhanced geostatistical interpolation, the method delivers spatially representative emission maps with high precision. This cross-disciplinary framework, transferring geochemical tools from volcano observatories to buried pipelines, demonstrates a practical and accurate pathway for methane leakage quantification and compliance with forthcoming EU emission regulations.