Cash Intensive Businesses

I work for a $300 million asset bank. I am trying to decide what constitutes cash intensive. I am thinking that it should be a.) any business that makes 15 or more cash deposits in a month, and/or b.) any business that deposits $20,000 or more in cash in a month. Any ideas?

I would go with the dollar amount only.
And $20M sounds like a number to start at - but of course all cash activity has to be weighed vs. the type of business that it is.

We use a pretty simple process and a low dollar amount. We label as cash intensive any business that deposits 10 or more $5,000+ cash deposits in one year. Now this is basically for all businesses that are not exempt already. I think we have about 20 or so that meet this definition. We are a $600 million asset bank.