A Toxic Trail

Mission chain
Briefing
We've got clean water again, but we can't risk people falling ill if the saboteurs return. We need to root them out once and for all.
Objectives
Directive · step 01
Return to the water intake below the Water Treatment Control building
Directive · step 02
Search the swamp for traces of the barrel's origins
Directive · step 03
Take a photo of the barrel truck
Directive · step 04
Search the truck for clues about the saboteur's identity
Sources: [1]