Was this ATM on-site (attached to a branch) or was this ATM in a remote location? We consider a remote ATM a form alternative delivery and would include in our branch opening and closing list in the bank's public file. As for documenting the reason for the closing, include in your file the analysis used to make the decision (transaction volume, etc.) If it is located in a LMI census tract, document your case even more - (distance to closest ATM and branch, how if any will removing the ATM affect access to bank services, etc.).