it depends upon how the drive was encrypted. There are two methods for protecting drives with FRP: Onsite and offsite.
Onsite: As files are transfered to the drive each file is encrypted in the same way it would be with location based encryption. To decrypt, a policy with the FRP Removable Media option should be set to allow unprotected access and allow explicit decrypt enabled. You will then be able to decrypt the individual files.
Offsite: An encrypted filesystem is created on the drive and the files are placed into the file system. When the drive is plugged into a system with FRP installed, FRP will mount the encrypted file system and display it as a drive. When plugged into a system without FRP, you must use the EERM.exe application to access the encrpyted file system. There is no method to decrypt this disk. The files must be transfered off the drive, the disk formated and the files transfered back to the drive.