On June 10th, APGA filed comments with the EPA supporting EPA’s proposal to allow utilities to estimate fugitive emissions of methane from leaks and other sources on the distribution system rather than physically measure the quantity of emissions. Since most of the system is underground, physically measuring leak rates would be difficult and expensive. EPA has proposed that utilities estimate emissions using leakage factors for mains, services and meter and regulator stations. APGA also supported EPA’s proposal to only require reporting from utilities with cumulative greenhouse gas emissions of over 25 000 tpy of CO2 equivalent. 1 t of methane is equivalent to 21 t CO2. APGA’s calculations show that this would exempt over 99% of public gas systems from having to report methane emissions, however systems with fossil fuel fired electric generation would have to report if their combined emissions exceeded 25 000 t CO2 equivalent.
APGA suggested several changes to the rule. Most importantly, the proposed rule would require utilities to conduct annual leakage surveys as above ground meter and regulator (M&R) stations using an optical gas imaging device. APGA urged EPA to allow utilities to use the leak detection equipment they currently use for leakage surveys required by pipeline safety regulations, e.g. flame ionisation or combustible gas indicators. We also urged EPA to allow utilities that did not want to do annual leakage surveys at above ground M&R stations to use an assumed leakage factor just as EPA proposed to allow for below ground M&R stations, mains and services. Finally, we suggested that if the utility has leak surveyed below ground M&R stations, mains and services during the year and found no leaks that these components should not be included in the count used to estimate methane leakage.
Read the article online at: https://www.hydrocarbonengineering.com/gas-processing/11062010/fugitive_methane_emissions/