How do we re-establish an owner and moderator for a group that has none?

The owner/moderator of the "LPNM-discuss" group no longer has the email account he used when he established the group. Consequently, our group no longer has an owner or moderator and is able to accomplish many functions within the group. For example, the group shows a dinner-discussion meeting on the 1st and 3rd Wed of each month. We changed the location over 3 years ago, and we changed it from Wed to Thur over 2 years ago, but we are unable to change it in the calendar module. How do we go about establishing an owner and moderator for our group so we can update thing when appropriate?