John, Kyle 

Found 1x10-3 torr*L/sec leak on pump side of 10" gate valve at Main Turbo Pump inlet (stem bellows area) -> Closed valved and valved-in IP1, 2, 3 and 4.  Also, valved-in HAM6 500 L/sec ion pump -> Vertex pressure normal now.  Will replace valve during next Vertex vent.