I testified before this committee last year about the pioneering scientists at Cornell University, Carl Schofield, Eugene Likens, and Charles Driscoll who were among the scientists responsible for establishing a strong link between acid deposition - primarily caused by upwind utilities - and the diminished ability of lakes to sustain healthy fish populations. We have made tremendous progress in understanding the causes and effects of acid deposition and ways to control it, but we still have a long way to go to mitigate these problems. We have learned, for instance, that the S02 emissions reductions required under the Clean Air Act Amendments of 1990 are insufficient to prevent the continued acidification of many lakes and further damage to sensitive ecosystems.
Perhaps most importantly, since the 1990 Amendments were enacted, we have learned that nitrogen oxides, which were largely ignored eight years ago, play a significant roll in acid deposition. And we have learned that acid deposition does not cause environmental degradation just in remote, high- elevation forests and lakes in the Adirondacks and northern New England. Rather, it poses a continuing and significant threat to the environmental quality of lakes, streams, forests, bays, and estuaries throughout the country. The Southern Appalachians, the Front Range of Colorado, and the San Bernardino Mountains in California are greatly affected by acidification and nitrogen saturation. Eutrophication is adversely affecting coastal waters throughout the eastern seaboard, including the Chesapeake Bay, Long Island Sound, and the Gulf of Mexico.
Achieving cleaner air has a two-fold solution: identify and control both mobile and stationary sources of pollution. The transportation sector accounts for nearly half of national NOx emissions. A large portion of these emissions are in the form of tailpipe exhaust from our national vehicle fleet. In recent years, advances in vehicle technology have produced Low Emission Vehicles (LEVs) - vehicles designed to reduce vehicle emissions by 90 percent. These vehicles were first sold in New York beginning with the 1998 model year. Unfortunately, New York can not see the full air quality benefits of these vehicles because New Yorkers do not have access to the low sulfur gasoline these vehicles have been designed to use. The problem is not limited to LEVs, although these vehicles are especially sensitive to gasoline sulfur. All vehicles in the national fleet with catalytic converters -- virtually all vehicles -- produce higher levels of emissions because of the high levels of sulfur in the gasoline they burn. Once the catalytic converter is damaged, it permanently loses its ability to filter pollutants.
In conclusion, I want to say that the success of the 1990 Clean Air Act Amendments cannot be questioned. The S02 Allowance Program established by that legislation has achieved extraordinary benefits at program compliance costs less than half of initial projections. The efficacy of the approach is proven. The current science indicates, however, that we did not go far enough in 1990 in setting our emissions reduction targets. We must build upon our accomplishments thus far, and to begin the work which remains to be done. Thank you.