If you've ever reviewed/been involved with review of a particular case history when things didn't go as expected you can use that as an example - can be a multidisciplinary case - doesn't have to be just physio.
Or - reviewing care pathways....
Or reviewing e.g. on a ward the standard outcome measure that is used, whether it is best for that client group
Or putting outcome measures in place to be able to monitor care that's being provided.

Unfortunately for you (in terms of interview) - most clinical governance work at the moment is being done at a higher level...

Reflective practice and use of outcome measures are good examples that you can give - anything to do with CPD too. CPD is a component of clinical governance and being newly qualified it is likely to be your biggest contribution. Have a look at this website:
http://www.cgsupport.nhs.uk/ - it should help with finding some examples