This article describes how to permanently remove file with PGP Desktop 9.0.x for Macintosh
The PGP Shred feature is used to completely destroy sensitive files without leaving fragments of their data behind. A file that has been removed with PGP Shred cannot be retrieved even with the use of disk recovery software.
How to Set PGP Shredding Preferences
Using PGP Shredder to Remove Files
Using the Shred Files Icon in the Toolbar to Remove Files
Using PGP Menu to Remove Files
Using PGP Shred via the Finder to Remove Files