After months of delay, former EPA air pollution chief Gina McCarthy was finally confirmed to lead the entire agency by the U.S. Senate last week, and it seems clear that her administration will focus like a laser beam on reducing carbon emissions from the nation's aging fleet of coal-fired power plants. That mission was also reinforced last week by Secretary of State John Kerry, who guest-blogged for our friends over at Think Progress about the development of a partnership with China designed to help reduce dependence on coal.

Aside from being an important global warming management strategy, the transition out of coal should help take the pressure off U.S. communities that are dealing with the impacts of coal harvesting and transportation, particularly for the export market. Unfortunately, when you put Kerry together with McCarthy, the picture looks far less clear when it comes to natural gas and oil.

Gina McCarthy and coal

First, the good news. In 2009, McCarthy was appointed Assistant Administrator for the EPA Office of Air and Radiation, continuing a decades-long career in public service focusing on air pollution management. The timing is significant because just two years earlier, the Supreme Court confirmed the EPA's authority to regulate carbon pollution, just as it regulates mercury and other airborne pollutants.

Coal accounts for a large chunk of electricity generation in the U.S., so with this regulatory authority cemented in place and a solid administrative background in hand, McCarthy is in a powerful position to shepherd through new regulations for emissions from power plants.

Since the new regulations do not depend on Congress to pass new laws, the anticipated result is a quick and sharp reduction in overall carbon emissions.

That solves part of the problem as far as direct U.S. emissions from burning coal are concerned, but as the past several years have shown, a booming export market for coal still leaves U.S. communities exposed to local impacts from coal mining and coal transportation.

This is where the aforementioned guest post by Secretary of State Kerry comes in (here's that link again). The focus is mainly on coal, with Kerry noting that "the United States and China are responsible for around 40 percent of global coal consumption." After running through coal-reducing strategies such as carbon capture and energy efficiency upgrades, Kerry makes the point that "these...measures will have all the more significance if we can help China diversify its fuel mix away from coal."

Of course, there are still plenty of other places in the globe for U.S. coal to go, but a firm agreement to transition out of coal with a top consumer like China would be a giant step in the right direction. Best case scenario: less overseas demand for U.S. coal, providing more leeway for the EPA to restrict destructive mining practices in the U.S., namely mountaintop removal.

Reading the EPA tea leaves on natural gas

Again, taking Kerry's article into consideration, the picture is much less clear on natural gas. Although Kerry reinforces the Obama Administration's longstanding position that natural gas contributes less to greenhouse gas emissions than coal, let's take note of some negatives.

First, pressure has been mounting on the gas industry to be more transparent about risk management, particularly regarding water contamination and methane leakage related to the drilling method known as fracking. That includes an effort by the EPA to work around some of the gaping regulatory loopholes granted to the industry in the past.

Second, while gas emits far less greenhouse gases when burned, lifecycle emissions are still a gray area. Some studies suggest that methane leakage from gas fields and points along the transportation route combine to make gas at least as polluting as coal.

Third, we've noted previously that the growing pressure to expand U.S. natural gas exports is contributing to contentious situations at the local level, for example in the tourism-friendly wine country of upstate New York, where plans are afoot to expand gas storage and transportation infrastructure.

All of this combines to make us leery of a policy that encourages China to transition into natural gas, given the potential for a ripple effect that increases the risks and impacts of gas production, transportation and storage here in the U.S. Right now it looks like the best case scenario for gas would involve the EPA in a more accurate assessment of risks and impacts, which will be difficult considering the aforementioned regulatory loopholes.

The Keystone XL Pipeline

As for the impact of the McCarthy confirmation on the U.S. oil landscape, speculation has been directed toward whether or not the new chief will steer the EPA toward supporting the proposed Keystone XL pipeline. Here, too, the picture is murky, though an article in The Guardian earlier this spring confirms our view that blocking the pipeline will not be a particular priority for McCarthy.

On the other hand, the groundwork has already been laid for the EPA to insist on more transparency regarding the local risks and impacts of the pipeline. Last year, when the State Department issued an environmental report that seemed to paper over the potential for significant impacts, the EPA issued a polite but strongly worded critique of the report's methodology.

Best case scenario: while pipeline advocates were quick to use the recent railway disaster in Canada as a case for pipeline safety, we're looking for the EPA to tease out the potential impacts on global greenhouse gas emissions as well as the impact of pipeline spills and breaks on local waterways along its route.

[Image (cropped): Power plant by Exothermic]

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