As a requirement of a state law enacted two years ago (AB 1371), California Public Utilities Commission (CPUC) staff has published a set of best practices (BP) for natural gas utilities for finding and fixing leaks.

Methane emissions mitigation advocates, such as the Environmental Defense Fund (EDF), praised the action as a “leakage epiphany and a very big deal.” EDF’s California methane mitigation champion Tim O’Connor said, “after years of science, politics and policy deliberations, [California] took one of its boldest steps yet in the quest to cut methane escaping from its vast network of aging pipes underneath city streets.”

California’s move comes in the same week that Boston University researchers published a report from a study of leaks in the Boston metropolitan area’s cast iron piping system that concluded government and system operators should go after all leaks — not just the biggest ones — for both safety and environmental reasons (see Daily GPI, March 30).

In consultation with the California Air Resources Board (CARB), the CPUC examined an array of BPs and came up with a series of recommendations as called for in AB 1371. The BP and repair standards are to be included in the state regulatory commission’s safety plans. Long term they will be included in a CPUC general order.

“There are mandatory minimum requirements proposed here that are intended to ensure that the utilities and gas storage operators are using BPs to reduce methane leaks and emissions,” the CPUC order states. The list of policy/procedure, record keeping, and training recommendations all carry a Dec. 15 compliance date this year.

“It should be mandatory for all utilities to create and file with the CPUC and CARB a compliance plan to compel utilities to self-audit and certify what specific BPs they are using to mitigate methane leaks and emissions,” the CPUC said. Working with CARB, the CPUC will review and approve the compliance plans and mandatory procedures and practices outlined by the state agencies.

O’Connor said the latest move by the CPUC should result in “a new direction for California, and likely for utilities across the nation.” The more aggressive approach is significant for California, he said, because it is a “climate leader that consumes 10% of the nation’s natural gas supply.”

Leaking or “fugitive methane” from the nation’s natural gas production, storage and delivery network was first outed in a scientific paper in 2012 (see Daily GPI, April 12, 2012).

Titled “Greater focus needed on methane leakage from natural gas infrastructure,” EDF’s initial findings were published in the Proceedings of the National Academy of Sciences.