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Wednesday, July 8, 2015

Gavin Dillingham and Alex Cuclis discuss the SCOTUS EPA air pollution ruling

US Supreme Court

HARC research scientists discuss the impacts of recent SCOTUS EPA ruling

By Steve Petteway, Collection of the Supreme Court of the United States (Roberts Court (2010-) - The Oyez Project) [Public domain], via Wikimedia Commons

Written by Alex Cuclis, Research Scientist, Air Quality and Emissions, and Gavin Dillingham, Research Scientist, Clean Energy Policy

People can be exposed to mercury from both natural and man-made sources. Exposure to high concentrations of mercury can be harmful. Therefore the EPA created rules to regulate one of the largest sources of man-made mercury, coal-burning power plants (called the Mercury and Air Toxics or MATS rule). The EPA is required to consider costs and benefits of its rule making. However, the US Supreme Court recently ruled that the EPA did not consider costs early enough in the rule making process. The future of EPA MATS now sits with the US Court of Appeals for the District of Columbia circuit. This court will decide what the EPA must do to have the MATS meet the expectations of the Supreme Court’s majority ruling. The timeline for this determination is unclear.

Why Limit Mercury Emissions?

Mercury is a highly toxic element that occurs both naturally and is introduced by human activities. Coal fired power plants are considered to be the largest source of mercury emissions and several of the largest plants (and highest mercury emitters) are located in east Texas. These emissions travel through air and water and accumulates in marine life. Although everyone has some exposure to mercury, high levels (typically from eating contaminated seafood) can damage immune and nervous systems and interfere with the developmental processes of fetuses, infants and children. The State of Texas has issued numerous seafood consumption advisories for mercury found in species of fish that are caught in Texas lakes and along the Texas Coast.

Capture and Removal of Mercury:

Coal fired power plants release mercury in three forms: elemental, oxidized, and as a particulate. Elemental mercury comes out of the stack. The particulate form is bound to the ash and can be removed by particulate matter (PM) control equipment such as an electrostatic precipitator (ESP) or fabric filter. A portion of mercury that has converted to oxidized compounds may be removed by either a wet scrubber or by activated carbon injection (ACI). Each of these control devices uses a different method to remove the mercury compounds.

Origin of MATS:

Most human sources of mercury have declined by about 75% between 1990 and 2005, however mercury from coal fired power plants has remained steady and represents about half of the emissions reported in EPA’s inventory. The current state of mercury pollution from these plants has motivated the EPA to pursue the adoption and implementation of the MATS standard. To that end, EPA published a regulatory impact analysis for the final mercury and air toxics standards (MATS) in December of 2011. They estimated that the annualized societal net benefits would be between $30 and $80 billion. Most of the savings are attributable to co-benefits from 4,200 to 11,000 fewer PM2.5-related premature deaths. Other savings are achieved from reductions in mercury emissions, calculated only for children exposed to recreationally caught freshwater fish. EPA states these benefits far outweigh the estimated compliance costs for mercury reductions as coal fired power plants of approximately $9.6 billion.

Impact of Court Decision:

The recent ruling from the Supreme Court on June 29th has been interpreted as a setback for President Obama’s environmental agenda. At first blush, it appeared the majority court opinion may have stopped MATS. However, with further analysis of the majority opinion, it appears that it is more likely that the EPA will need to rework its costs calculations.

Fortunately, the issue with MATS was not EPA’s regulation of mercury and other pollutants, nor was it that EPA requires state and local governments to comply with this standard. Rather, the problem was largely with how the EPA went about calculating the costs of compliance for coal fired power plants. The plaintiff in the case, the state of Michigan, filed the initial suit arguing that EPA did not consider the costs of compliance during the initial finding phase of the rule making process. During this phase, the EPA must determine whether the regulation is “appropriate and necessary.” The suit argued that the EPA did not consider costs during this time and thus did not follow the appropriate procedure to develop this regulation. The majority of the court concurred with this argument, thus tossing the rule back to the US Court of Appeals for the District of Columbia Circuit. The DC Court has two options, it can make the EPA start over again or it can have the EPA recalculate the costs of the rule in a way that satisfies the court’s opinion.

Clean Power Plan:

The Clean Power Plan comes from section 111(d) of the Clean Air Act which allows the EPA to regulate emissions from existing power plants. Under this plan, each state has a greenhouse gas reduction goal. The Clean Power Plan is to be released in August of this year and states will have one year to develop a state implementation plan demonstrating how they will meet their goal.

With the ruling by the court, there was some concern over how this may influence the viability of the Clean Power Plan, the latest effort by the EPA to reduce greenhouse gas emissions from existing power plants. Based on the ruling, what is most likely to happen is the EPA will go back through its rule making process to ensure that it has followed all of the appropriate requirements to meet the standards determined by the court’s opinion. It is possible, but unlikely that the EPA will further delay the release of the Clean Power Plan.