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New facility-level methane (CH₄) emissions measurements obtained from 114 natural gas gathering facilities and 16 processing plants in 13 U.S. states were combined with facility counts obtained from state and national databases in a Monte Carlo simulation to estimate CH₄ emissions from U.S. natural gas gathering and processing operations. Total annual CH₄ emissions of 2421 (+245/–237) Gg were estimated for all U.S. gathering and processing operations, which represents a CH₄ loss rate of 0.47% (±0.05%) when normalized by 2012 CH₄ production. Over 90% of those emissions were attributed to normal operation of gathering facilities (1697 +189/–185 Gg) and processing plants (506 +55/-52 Gg), with the balance attributed to gathering pipelines and processing plant routine maintenance and upsets. The median CH₄ emissions estimate for processing plants is a factor of 1.7 lower than the 2012 EPA …