Significant
(6) Significant means, in reference to an emissions increase or a net emissions increase, and notwithstanding the definition of significant in 40 CFR part 51, appendix S, paragraph II.A.10, any increase in actual emissions of volatile organic compounds or oxides of nitrogen that would result from any physical change in, or change in the method of operation of, a major stationary source locating in a serious or severe ozone nonattainment area if such emissions increase of volatile organic compounds or oxides of nitrogen exceeds 25 tons per year when aggregated with all other net emissions increases from the source over any period of 5 consecutive calendar years that includes the calendar year in which such increase occurred.