Default User Role

I have a WooCommerce Shop and a UM member portal on my site. Access to the portal is only available after an application is submitted and reviewed by the board, so no Member registration is necessary(it is manual).

All WooCommerce Customers are given the default UM role, though they will never qualify to be a member on the site. Is there a way to remove UM roles for registrants? All Woocomerce customer will never need the functionality of a member (only access to there store accounts).