The PGP Whole Disk Encryption for Mac OS X Quick Start User Guide version 10.0 contains the following remarks:

PGP Corporation deliberately takes a conservative stance when encrypting drives, to prevent loss of data. It is not uncommon to encounter Cyclic Redundancy Check (CRC) errors while encrypting a hard disk. If PGP WDE encounters a hard drive with bad sectors, PGP WDE will, by default, pause the encryption process. This pause allows you to remedy the problem before continuing with the encryption process, thus avoiding potential disk corruption and lost data.

To avoid disruption during encryption, PGP Corporation recommends that you start with a healthy disk by correcting any disk errors prior to encrypting.

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As a best practice, before you attempt to use PGP WDE, use a third-party scan disk utility that has the ability to perform a low-level integrity check and repair any inconsistencies with the drive that could lead to CRC errors. These software applications can correct errors that would otherwise disrupt encryption.

The PGP WDE Windows user guide suggests SpinRite or Norton Disk Doctor. What recourse do I have on the Mac?