Notwithstanding the setback provisions set forth in this section,
such setbacks from property lines do not apply if the application
is accompanied by a legally enforceable agreement that runs with the
property for a period of 20 years or the life of the special permit,
whichever is longer, that the adjacent landowner(s) agree(s) to the
elimination of the required setbacks. These setback requirements in
this section can only be varied through this agreement process with
adjoining landowners and not through a variance with the Zoning Board
of Appeals. Any agreement to the elimination of such property line
setbacks shall not constitute the reduction or elimination of required
setbacks from structures, as previously identified, and such setbacks
from structures, for safety reasons, shall not be reduced or eliminated.