Confidential Information

I have an additional question for paper that includes confidential/sensitive information. Since my building is a bank, ALL paper is considered sensitive information for security reasons. We have locked blue bins that get taken away and recycled/shredded once a week. The desk side recycleable bins get dumped into these locked bins twice a week by the janitorial staff. How would I go about tracking that in the audit since this would really help our diversion rate because paper is our top recycled item.