Method and apparatus for data protection

Described is a method for secure data disposal. Data stored in storage volume(s) is encrypted with a specific encryption key. Before the key is disposed of, a clear text string is encrypted with the same key and the encrypted data is associated with the clear text string and stored in a repository. When a new key is created to encrypt a new volume, each of the encrypted data in the repository is checked to determine whether the encryption of the associated clear text string using the new key generates the same encrypted string as the stored encrypted data. If the result of the encryption of the clear text string matches at least one stored encrypted string, the associated new key is not used and another key is generated until the new key results in an encrypted string which does not match any stored encrypted strings.