https://www.scientificamerican.com/article/oil-and-gas-facilities-leak-more-methane-than-previously-thought/

A new study by the Environmental Defense Fund and a team of university scientists estimates that the U.S. oil and gas industry emits 13 million metric tons of methane into the atmosphere each year, losing $2 billion annually from over 400 leak-prone drilling and processing facilities.

The losses, according to the study published yesterday in the journal Science, are 60 percent more than those estimated by EPA.