*as first published in the News Journal Dec. 16, 2013   Upwind power plants are not causing significant pollution in Delaware or in other mid-Atlantic and Northeast states as is commonly believed. For the first time, Delaware will meet all air-quality standards this year. It is time to celebrate the progress we have made in reducing air pollution and to move on to other problems instead of worrying about what other states are doing. The primary remaining emission source for nitrous oxide, a precursor for ozone, is on-road and off-road vehicle engines. National rules already in place to increase gas mileage and to lower tailpipe emissions will reduce nitrous oxide in Delaware’s air by about 30 percent over the next decade, and we will continue to meet air-quality standards.   Gov. Jack Markell has joined with seven other northern states in calling for the creation of an Ozone Transport Region to force nine upwind states to reduce power plant emissions. Ozone can affect health, especially in people with chronic bronchitis and asthma.   Downwind states like Delaware lament a lower court finding a proposed Environmental Protection Agency (EPA) rule to limit cross-state pollution is unconstitutional. The timing of the announcement was meant to influence a Supreme Court review of the regulation. We note the eight complaining states emitted twice the NOX (nitrous oxide) allowed under the regulation in 2012. If these northern states really want to reduce ozone pollution, they are fighting the wrong battle.   The air pollution regulations on power plants of the last several decades have been very successful.   Power plants have reduced air pollution emissions by about 95 percent. In addition, air pollution has been reduced recently by switching many power plants from coal to cleaner burning natural gas and by closing older coal-fired generators.   The EPA uses sophisticated computer models to estimate the downwind impact of air pollution from various sources. When proponents of the cross-state rule speak of the science supporting their claims they point to EPA computer model runs based on 2005 emissions data. Even that outdated run showed an insignificant change in health costs in Delaware related to ozone reduction from the regulation. We now have a more recent run completed for Delmarva Power as part of their state-required Integrated Resource Plan. The updated computer projection shows no reduction in air pollution in Delaware over the next decade from power plant regulations. That is true for both ozone-forming nitrous oxide and fine-particle-forming sulfur dioxide, even when the cross-state rule is considered.   There is no doubt air pollution rules were needed. The EPA established air pollution standards that set the maximum allowed exposure to various pollutants. In 1980, New Castle County was above or way above the standard on 143 days. Originally, six pollutants were monitored, but only two, ozone and fine particulate matter, are still measured, as the other pollutants are way below the standard. Even with much tighter standards, 2013 saw only 16 hours, or 0.2 percent of the time, on two days just barely above the standard for ozone. The average maximum level of fine particles is about 20 percent better than the standard and is closing in on estimated pre-industrial levels. Reducing air pollution should no longer drive major policy decisions.