1. A distributed storage (DS) unit comprises: a plurality of memory devices operable to store a plurality of collections of encrypted and encoded data slices, wherein a collection of encrypted and encoded data slices of the plurality of collections of encrypted and encoded data slices includes a common data aspect, wherein encrypted and encoded data slices of the collection of encrypted and encoded data slices are produced by individually encrypting corresponding encoded data slices using a common encrypting character string and representations of the corresponding encoded data slices, and wherein the corresponding encoded data slices are dispersed storage error encoded portions of a plurality of data segments; local memory operable to store the common encrypting character string regarding the collection of encrypted and encoded data slices and to store the representations of the corresponding encoded data slices; and a processing module operable to: receive a request regarding at least a portion of the corresponding encoded data slices; identify the common encrypting character string of the corresponding encoded data slices; and when the request is to delete the corresponding encoded data slices, obfuscate the common encrypting character string in the local memory such that the collection of encrypted and encoded data slices are effectively incomprehensible.