Notwithstanding the provisions of regulations adopted by the Commissioner of Energy and Environmental Protection under subsection (d) of § 22a-449, (1) a town, regional school district or incorporated or endowed high school or academy approved by the State Board of Education pursuant to § 10-34 shall have until October 1, 1991, or five years after the life expectancy of an underground storage tank system, as defined in subdivision (5) of § 22a-449a, of a public school building or building of such an incorporated or endowed high school or academy, whichever is later, to replace such a system, provided application for a school building project for such purpose is made on or before October 1, 1990, or October first of the year preceding the fifth year, as appropriate, to the state Department of Education pursuant to § 10-283 or 10-285b, and (2) a nonpublic elementary or secondary school shall have until October 1, 1991, or five years after the life expectancy of such an underground storage tank system of a nonpublic school, whichever is later, to replace such a system.