https://www.pennlive.com/opinion/2019/05/state-natural-gas-rule-misses-chanc...

PA State natural gas rule misses chance to curb climate changing pollution | Opinion Essay by Prof. Peter DeCarlo, PennLive.com, May 6, 2019 We must reduce air pollution caused by Pennsylvania’s natural gas industry. Lawmakers in Harrisburg are working on a rule to do just that, but they’re only getting it half right.

The Pennsylvania Department of Environmental Protection’s (DEP) current proposal to curb air pollution at thousands of existing natural gas facilities targets health-damaging and ozone-forming volatile organic compounds (VOCs), but only describes reducing methane emissions as a “co-benefit.” Methane is a powerful greenhouse gas and a significant cause of climate change. It is unlikely we will achieve the goal of 80 percent reductions in greenhouse gas emissions by 2050 as promised by Governor Wolf if we do not directly regulate methane.

Targeting methane reductions must be a central focus of the proposed rule. It cannot be downgraded to an indirect benefit.

As an atmospheric and climate scientist at Drexel University, I’ve studied leakage from the natural gas industry throughout the Commonwealth for eight years. My research team documented a 300 percent increase in methane emissions in northeastern Pennsylvania between 2012 and 2015. During that same time period, the estimates from the natural gas industry suggested a 30 percent decrease in methane emissions. That disturbing discrepancy is a clear indicator that the state must to do more to measure and mitigate methane emissions from existing natural gas sites and not rely on imprecise estimates.

The draft rule as currently written will allow leaks in many parts of the state to emit substantially more methane before triggering VOC controls. Most of the Marcellus Shale in Pennsylvania is comprised of dry gas, meaning it contains a lower fraction of VOCs in the natural gas than the “wet gas” area of the state (primarily southwest Pennsylvania). By not addressing methane leakage directly, DEP would be allowing a significant amount of methane leaks to occur at gas infrastructure throughout the state. From a climate change perspective, this is irresponsible.

In addition, the rule also unfortunately includes an exemptions for natural gas wells that produce a low amount of gas. Research has shown that these low-producing wells can actually emit just as much methane or more than higher producing wells. In the interest of limiting climate-damaging methane emissions, this exemption must be removed from the proposed rule.

I voiced my support for a rule that addresses these shortcomings at a recent meeting of DEP’s air quality advisory committee in Harrisburg. I shared my research findings concluding that methane emissions are considerably higher than industry and DEP estimates.

As the rule advances to the Environmental Quality Board, the state’s environmental rule-making body, and becomes available for public comment, I hope DEP will improve the draft rule by specifically targeting methane at existing natural gas operations in Pennsylvania and removing exemptions. If we want a chance to avoid the impacts of catastrophic climate change, DEP must do everything within its authority to protect current and future generations.

Peter DeCarlo, associate professor at Drexel University’s College of Engineering and College of Arts and Sciences.