Tomorrow morning, the area around the World Trade Center site will be closed for a "full scale training exercise" held by the NYC Office of Emergency Management and the Port Authority of NY and NJ. The exercise will simulate an explosion in one of the PATH train tunnels and will include over 800 first responders. The following streets will be closed to pedestrian and vehicular traffic between 6 a.m. and about 11:30 a.m.: Greenwich Street, West Broadway, and Church Street between Vesey Street (included) and Warren Street (not included); Vesey Street, Barclay Street, Park Place, and Murray Street between Broadway (not included) and West Street (not included). Also, the PATH will be not stopping at WTC—here are more details on PATH service tomorrow morning. Photograph of a 2007 drill at Penn Station from the NYC OEM