2nd time this has happened in 3 months: first was the intermediate pipe stationed right in the middle of the engine (plastic part, common failure) this time I do not know but I lost most of my coolant in the tank so it can't be good.

Car has seen 30,000 miles (48,000km) in 4 years and this happened on a brief WOT.

I'm suspecting a failed water pump because I heard strange noises under the bonnet...

Are these items so prone to failure? Maybe it's time for a full coolant line refresh.

 

Water pump is prone to failure. Very likely the issue. They do make a rattling noise before failing

Look online here - someone posted a replace for the water pump and also all the cheap plastic bits of the cooling system. Maybe worth your while

 

I've heard that plastic impellers in the water pump can fail and get into the engine. Is it possible that waterway was blocked due to this part's failure causing higher hydraulic pressure -> coolant burst out?

It's in a repair shop now but they said leak is not present except for some error code memory in 2nd gear (combustion related.) It's strange because I saw white smokes coming out of the engine bay when this happened and I was drawing on the road with coolant as if I were doing burnouts.