Oooh, I haven't tried critting a thaumiel thing before, here goes:
This doesn't feel like a Thaumiel-class SCP to me. We're given no hint as to what the SCP it destroyed in the second test addendum was, and the way it's written makes it sound like the "test" was an accident. Accidentally destroying another SCP object for no good reason doesn't make something Thaumiel, it just makes whoever was leading the test look incompetent.
Admittedly, I'm also a bit confused by how this SCP object functions. Maybe I'm reading this incorrectly, but if the water freezes everything but gasses, and anything frozen by it also takes on its anomalous properties, then why aren't the hot tub, floor, etc. also frozen? How are objects and bodies able to be safely retrieved? None of this feels very clear to me.
All that aside, there are some grammar issues (ex. "The spa and surrounding stores containing SCP-XXXX has been purchased" should be "The spa and surrounding stores containing SCP-XXXX have been purchased") and I think it would be helpful to look up some scientific references on temperature and flash-freezing and the like, because what's here doesn't feel at all scientifically accurate, even for an anomaly.
