I'm not sure of the issues here. Clearly water is used for cooling, but there could be a closed system of clean water that is cooled with e.g. seawater by simple conduction.
The other thing seems to be that water is used for cleaning, which means it ends up containing toxins. That seems to be a much harder problem to solve since you need to filter/destroy/neutralise the toxins?
Might not scale well if it heats up the localized conduction region or leaches out. The NYC subway use to need to be heated quite a bit because all the surrounding rock absorbed all the heat. Now, it’s saturated and requires massive cooling systems
Integrated Circuits. The article is on a technical website so I think they assume you already know what is the acronym of IC. But anyways add two words of explanation wouldn’t hurt anyone.
The other thing seems to be that water is used for cleaning, which means it ends up containing toxins. That seems to be a much harder problem to solve since you need to filter/destroy/neutralise the toxins?