ACC rebuilt the Penn Station waiting and track areas for the newly-introduced Acela High Speed trains. Work included construction of an ultra-modern waiting area with a luminous ceiling and aluminum glass radius walls, as well as new masonry walls and finishes including terrazzo flooring, ceramic tile wall finishes, metal pan ceilings, and stainless steel/glass doors. The existing metal pan stairs were removed, and new escalators were installed with supporting concrete slabs and structural steel elements in place. During the project, platforms and public areas were in use 24-7.