This quest is not available in game.
Capture Crown Guard Tower, Eastwall Tower, Northpass Tower and Plaguewood Tower in the Eastern Plaguelands, then return to Emmisary Whitebeard at Light's Hope Chapel.
Welcome to the Plaguelands, <name>. As you know, the Forsaken and their allies hold the lands to the west of here against our best efforts. The Alliance commanders have decided that here in the east, we will establish new fortifications to tighten the noose around our enemies.
Towers long abandoned since the days of Lordaeron are to be seized and rebuilt for this purpose. These lands are dangerous, and we could use your help.