Well, after reading enough posts on LIM/UIM, I reluctantly decided to pop off the engine cover and check mine.
I'm assuming this is the start of a failure with the dried orange goo around the LIM? Its never wet, and I've found no oil in the coolant/coolant in the oil. Could it just be some crud (wishful thinking)?
The leak that kills is internal. Not external. However:
You have an L36 with an OEM UIM and are using DEXcool. It is failing. There is no question. You can deal with it ahead of time, or possibly have to replace the engine. L36 engine replacements on this Forum outnumber ALL OTHERS combined by at least 3:1.