It's what happens when the seal on the bottom of the clutch master cylinder blows out, you can visually look at it and generally see it on the bottom of the master cylinder on the bottom underneath the reservoir, and also look for fluid leaking from under it (its DOT3 brake fluid btw).
I know, I'm in the middle of replacing mine after a brand new one just blew out 6-7 months after installation. Fortunately it's a pretty easy DIY replacement, you pull out the Intercooler, undo the clutch fluid line from the master cylinder, then unclip the shaft from the lever under the dash (it's above and to the right of the gas pedal, the clutch pedal activates it using a shaft that runs across under the dash above the gas pedal). Pull the clip securing the pin that connects the shaft to the lever, then pull the pin.
Then, undo the two bolts holding the Master Cylinder to the firewall and it should then wriggle right out.
Use the position of the pedal adapter to position the adapter on the shaft of the new master cylinder and lock it into position with the lock nut (then when you install it, it should line right up with the hole in the lever). Replace the pin and secure it with its clip.
Bolt it to the firewall & then reattach the clutch fluid line to the slave cylinder
Then you should be able to bleed the clutch system, and then replace the intercooler.