If senators are interested in a particular program, maybe because the Auditor General has commented on it before, there are two ways of doing it. Either the committee can ask for further written information from the Auditor General, a further report on the particular matter, or officers of the audit office can appear before the committee and answer questions about particular programs and parts of departments that have had difficulties with their performance and their efficiency. So those are two ways the committees can interact with the auditor's office.
On April 4th, 2012. See this statement in context.