A new EPA report, Evaluating Ozone Control Programs in the Eastern United States: Focus on the NOx Budget Trading Program, 2004, shows that decreases in emissions of nitrogen oxides (NOx) signal that air quality throughout the eastern US is improving.

According to the report, the EPA NOx SIP Call rule, which directed 21 eastern states and the District of Columbia to reduce emissions of NOx during the summer months, has resulted in power industry summertime NOx emissions dropping significantly in 2004.

All states subject to the NOx SIP Call chose to comply by participating in the EPA-administered NOx Budget Trading Programme. Under this programme, the report shows, total summertime NOx emissions from power plants and other large combustion sources were 30% lower than in 2003, and 50% lower than in 2000.

The NOx Budget Trading Programme allows emitters to choose from a variety of options to meet emission reduction targets including reducing generation from certain units, improving the combustion process, or using NOx control technology. Alternatively additional emission allowances may be purchased from sources using less than their allocated amount.

In 2004, nearly all of the more than 2,500 units covered by the programme held sufficient allowances to cover their emissions, with just two units at one facility subject to automatic penalties.

“The NOx Budget Trading Programme is yet another example of how market-based trading programmes are significantly reducing emissions of air pollutants,” said EPA Administrator Stephen L. Johnson

Further NOx emission reductions are anticipated under the on-going NOx SIP Call and the Clean Air Interstate Rule (CAIR) issued in March.