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 Mark Schoeberl, NASA.

Clean Air Act

The 1980’s

During the early years of the Enforcement Section – the decade of the 1980's – the volume of Clean Air Act (CAA) enforcement activities was much less than it was under the Clean Water Act (CWA) and the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA or Superfund). As is still true today, the entirety of the Section’s CAA enforcement work grew from EPA’s targeted inspections, and, in the 1980's, the Environmental Protection Agency (EPA) had not yet built the enforcement interest in pursuing major CAA enforcement initiatives.

The statute and its regulatory offshoots are very complicated and many of the Act’s most potent enforcement provisions – such as New Source Review – were simply untested. So, during the 1980's, the Enforcement Section’s CAA docket was comprised, for the most part, of small cases enforcing violations of regulatory requirements to control asbestos emissions that were imposed on owners and operators of demolished or renovated commercial and residential facilities.

The 1990’s

The emergence of CAA judicial enforcement as a potent tool to produce nationally significant cases with substantial environmental benefits began in the early 1990's, and it opened on two fronts – stationary sources and mobile sources.

Stationary Sources – Industry-Wide Enforcement Against Wood Products Industry and Oil Refiners

On the stationary front, EPA and the Department of Justice began to enforce the New Source Review provisions of the statute in a series of industry-wide initiatives that sought emission reductions not just on an ad hoc plant-by-plant basis, but on a broader company-by-company basis. Initially, the wood products industry came under scrutiny, and the leverage supplied by the potential for civil litigation led to major settlements with Louisiana Pacific, Georgia Pacific, Willamette Industries, and Boise Cascade – all the major players in that industry. These settlements were among the first “National Settlements” to cover multiple facilities and produce substantial emission reductions without proving violations at each and every plant covered in the settlement.

The National Settlement model for major stationary sources proved even more successful when the focus shifted to the nation’s oil refiners. Beginning with a series of inspections in 1998, EPA and DOJ embarked upon an initiative to secure industry compliance with a series of requirements under four critical emission control programs -- New Source Review, Leak Detection and Repair, Flaring, and Benzene standards. Koch Industries was the first refinery to sign a settlement resolving these claims.

Outcome: Over twenty more refiners have followed suit, now bringing nearly 90% of the nation’s oil refining capacity under consent decrees that address those four key programs. To date, the results of this enforcement initiative have reduced combined emissions of nitrogen oxides and sulfur dioxide by nearly 350,000 tons each year.

Mobile Sources -- the Domestic and Foreign Automobile Industry

At the same time as enforcement efforts against major stationary sources of pollution gathered steam and produced important settlements, EPA and DOJ began developing significant actions involving mobile sources, starting with the domestic and foreign automobile industry. In the mid-1990's every major domestic manufacturer of automobiles -- GM, Ford, and Chrysler -- as well as foreign manufacturers (including Honda and Toyota), were targeted for violations of the Clean Air Act’s prohibitions against installing “defeat devices” that reduce the effectiveness of equipment designed to control exhaust emissions of hydrocarbons and nitrogen oxides.

The enforcement effort hit a high point with major national settlements with all the major manufacturers of heavy duty diesel truck engines that power large commercial trucks and other vehicles used across the country that had also allegedly installed defeat devices that made their engines deceptively perform better on EPA’s laboratory emission tests than on the open road.

Outcome: The resulting settlements with Cummins, Volvo, Caterpillar, Detroit Diesel and others, will avoid millions of tons of excess emissions of pollution from these sources across the entire country.

2000 and On – National Settlement Program Paradigm Shifts to Litigation Against Coal-Fired Power Plants

Until the late 1990's, the company-wide National Settlement paradigm was producing important environmental results from both stationary and mobile sources without the need for significant litigation. After wood products and oil refineries, the Section successfully achieved important, broadly focused settlements with members of the steel industry, ethanol producers, cement plants, sulfuric acid manufacturers, and facilities that use chlorinated fluorocarbons (CFCs) which vent to the atmosphere and damage the Earth’s protective ozone layer.

However, the paradigm changed when the Section’s focus shifted to the nation’s aging fleet of coal-fired power plants. These facilities are the largest stationary sources of emissions of sulfur dioxide and nitrogen oxides in the country, and those located in the Midwestern and Appalachian states contributed to significant pollution problems in downwind states in the Northeast.

Settlement overtures did not work initially with any of these operators, and so, in the largest coordinated environmental enforcement filing in history, the Enforcement Section in November 1999 sued seven operators of coal-fired power plants located across the Midwest and South under the New Source Review provisions of the Act. Many of those initial cases settled after years of litigation; some, like Duke and Alabama Power, are still being litigated. Since then, the Section has sued additional operators and, as of the end of 2014,  has entered into 28 judicial settlements with truly staggering results.

Outcome: When the more than $13 billion worth of pollution controls required by these settlements are fully operating, they will remove more than two million tons of pollution each year from the nation’s airshed.

As the Enforcement Section looks forward, continued litigation of New Source Review cases against power plants will continue. New cases have been filed, and settlement negotiations will continue with other operators.

The Section will also spend more of its time enforcing:

  • mobile source violations by foreign manufacturers of smaller engines used in all manner of portable and stationary equipment; and
  • CAA’s standards limiting emissions of hazardous air pollutants by stationary sources like secondary aluminum smelters and natural gas processors.

The environmental benefits from expending these resources on the most heavily polluting industries produce a tremendous “bang” for the enforcement “buck.”

Updated April 4, 2023