@zgall1 As mentioned in the tool tip, the minify cache folder contains the older, non-expired cache, as well as the temporary files used to generate the minified files.
All old and expired files will be deleted once every day via cron job. You could confirm it by install WP Crontrol plugin and make sure you have wpo_minify_purge_old_cache event
Looking at your stat the non-expired cache files and temp files seems to be too large (in size and no. of files)
1. Make sure the above mentioned cron event is present and cron jobs are working correctly on your website..
2. Please inspect your wp-config.php file. If it happens to have define('WP_DEBUG', true); rule, then make sure the value is false
