Go towards the buildings. Soon you should meet with some resistance from Wretches of a new kind. What makes them different from regular Wretches is the fact they had contact with Imulsion and explode after death. After killing the first wave, stock up on ammo and head further. Finish off two more enemies and find a brick building with a skull painted on a wall. Go inside - at the end of the wooden pier you'll find 19.Tag.
There's an elevator in that building but it's useless without electricity. You can find the generator in the third building. Turn it on, get back to the elevator and go up. Enter the manufacturing plant through the window.
You need to get through the door. Go down any hallway - the button you press won't do anything. Go back and pick the other hallway. In the room with corpses open the door. A man will lead you to the lion's den. Unfortunately, in a room with unstable floor your guide will meet his fate. Go slowly if you don't want to repeat his mistake. If the floor starts shaking, go back and pick a different way. In the right corner of the room you can find 20.Tag.
You'll get attacked by a group of Wretches. Don't try to aim, shoot from the hip and stay mobile. A few rooms away you'll find a handle - use it. Replenish your ammo and go downstairs. Your old friends decided to show up - welcome them with appropriate cordiality. Use another handle to open the grating. Drones and Wretches appear, kill them using the usual methods. Find another door, but before your droid opens it, you'll need to fight a a Boomer and a Grenadier. After that, get through the door, go downstairs and look for 21.Tag. Press the button on the console nearby. Hop into the cart.