PARENT SESSION
Symposium #8: Nitrogen deposition in the Western U.S.... Is there cause for concern?.
Sponsored by ESA Rocky Mountain Chapter
Organized by: H.M. Rueth and J.S. Baron.
Tuesday, August 7, 2001. 8:00 AM to 12:00 PM. Madison Ballroom A

Nitrogen emissions and deposition in the U.S.: Current policy and future prospects.

Haeuber, Richard¹, ¹

ABSTRACT- The list of harmful ecological and human health effects of nitrogen emissions and deposition include acidification of soils, streams, and lakes; loss of soil nutrients; eutrophication of estuarine and near-coastal waters; degraded drinking water quality; increased regional concentrations of ozone and fine particulate matter; reduced visibility; and increased atmospheric concentrations of greenhouse gases. This talk describes the legislative and policy framework regulating nitrogen emissions in the United States. Legislation and policy have largely focused on reducing NOX emissions. Title IV of the 1990 Clean Air Act Amendments achieved substantial emissions reductions from the power generation sector. Several recent and pending regulatory actions are expected to achieve further NOX emissions reductions from both stationary and mobile sources. In addition, various legislative proposals for further NOX emissions reductions from the utility sector have been introduced in recent Congressional sessions. Results of model runs will be shown, demonstrating Title IV (Phase I) emissions reductions, projected reductions from Title IV (Phase II) implementation in 2010, and potential emissions reductions from legislative proposals. However, important nitrogen species (e.g., NH₄, NH₃) from other sources (e.g., agriculture) remain largely unregulated, contributing to deposition levels in the west. The talk will conclude with a brief discussion of the prospects for further control of emissions and deposition of nitrogen.

KEY WORDS: environmental policy, nitrogen emissions, nitrogen deposition, Clean Air Act Amendments