Exposed by removing the side panels in the boot (plus a few other bits on the drivers side) but to remove them you need to lower the rear bumper section.
Not wanting to remove the bumper I sealed all around each vent from inside the boot with an ample beeding of a good quality silicon sealant. The sealant I used as shown in the photo is one used in caravan manufacture to seal and hold joints together.
More possible water leaks – see … water leaks – MG ZT cars info news and reviews
MG ZT info mods and maintenance 