Not altered or changed.

adjective. Remaining in its initial state

adjective. remaining in an original state

"“On the other hand, if current plans for SR 520 remain unaltered, there are significant, perhaps insurmountable, obstacles to building light rail in the corridor, even if formal planning efforts identify light rail as the preferred option.”"

altered  changed  

dateless  in-situ  timeless  unedited  unmoved  

altered  

defenseless  dissimilar  indestructible  intact  nonexistent  

abiding  changeless  constant  continuing  durable