What terrain clearance requirements will be placed upon ATC? If they will have nothing better than Grid LSALT this will be unworkable. They’ll need to separate above 1500 AGL but can’t “vector” (assign headings) below the GRID LSALT. It will require more specific radar terrain clearance charts for the whole of the east coast “J curve”. Currently they can’t even use 25NM Aerodrome minimum safe altitude charts for heading assignments