To add a second menu, I added the following code to my child theme functions.php file.
/* adding footer menu, second nav to child theme */ register_nav_menus( array( 'primary' => __( 'Primary Menu', 'CHILDTHEMENAME' ), 'secondary' => __( 'Secondary Menu', 'CHILDTHEMENAME'), ) );
This brought up a 2nd menu in the Theme Menu options.
I then was able to place it in the footer, calling it with the following code:
<?php // footer menu wp_nav_menu( array('container_class' => 'menu-footer', 'theme_location' => 'secondary' ) ); ?>
I thought I would post this as I didn't find any explicit information on how to do this... and it seems to have changed slightly from twenty eleven. Hope it helps those who are looking...