An easy thing to do instead of joining specific mailing list, would be to click on the board you're interested in, such as "Jeollanamdo" or "Gwangju" and then pressing the button "NOTIFY".
This allows you to receive a notification by e-mail of new posts to that specific board. Meaning if you're interested in what's going on for Gwangju, then this feature will keep you alerted by e-mail.
EDIT: Feature no longer available due to security risks. Only Global moderators (JLP Co-ordinators), and the administrator have access to this feature.
