Answer:
If the dormant account statement contains any disclosures required by Regs. E, DD, or other federal regulations, the disclosures must be delivered "in "writing." The only legal way to substitute electrons for paper is to obtain the customer's demonstrable consent via ESIGN. Since you are unable to contact the customer, you will not be able to obtain consent.
If no regulatory disclosures are involved, you could switch to e-delivery under the authority of your state's UETA--but you're still going to need some form of agreement from the customer.
First published on BankersOnline.com 10/17/11