Polluted water is in a closed loop feeding a metal refinery - when a game is saved/reloaded the metal refinery 'eats' the coolant.
There was no pending orders in the refinery. Over time the closed loop becomes empty.
Steps to Reproduce
1. Fill a Metal Refinery with polluted water to a non max-capacity value. 2. Save Game 3. Reload Game. 4. Check quantity of polluted water in Metal Refinery.
This issue has not been confirmed by a developer yet.