After completion of the ongoing research concerning military use of lands in the Orchard Training Area or after the date 5 years after
August 4, 1993, whichever first occurs, the Secretary shall continue to permit military use of such lands, unless the Secretary, on the basis of such research, determines such use is not compatible with the purposes set forth in
section 460iii–2(a)(2) of this title. Any such use thereafter shall be permitted in accordance with the Memorandum of Understanding, which may be extended or renewed by the Secretary so long as such use continues to meet the requirements of subsection (b)(2) of this section.