The LISS recently prepared an estimate of the indirect deposition of nitrogen to Long Island Sound from the Connecticut and New York portions of the watershed. Based on this analysis, the combined direct and indirect deposition of nitrogen from atmospheric sources is estimated to be 14.3 percent of the human-caused load to the Sound. Oxides of nitrogen (NOx) contribute to both the atmospheric nitrogen that reaches the Sound and ground-level ozone, which causes human health problems when it reaches dangerous levels in the air. Through the Ozone Transport Assessment Group, air pollution managers from the eastern states have submitted specific recommendations to EPA for reducing NOx emissions to address the problem of ozone. Computer modeling by the Chesapeake Bay Program has estimated that reducing NOx emissions through implementation of the mandatory Clean Air Act requirements will result in significant improvements in dissolved oxygen levels in Chesapeake Bay. Such modeling has not been performed for Long Island Sound. However, simple calculations that apply Chesapeake Bay derived estimates to the New York and Connecticut portions of the watershed suggest that implementation of the Clean Air Act could achieve around 5 percent of the Long Island Sound nitrogen reduction target.