[rules-users] Stateless session with pre-inserted facts

I have a need to execute a set of rules on a complicated hierarchical data structure where some of the rules use a bunch of reference facts. At the moment I load the reference facts and the hierarchical structure into the WM of a stateless session on every execution. There are a lot of reference facts and they start off in the same state on every execution though they can get modified as part of the rules execution. I would really like to be able to save the WM after inserting the reference facts so that I can start each execution with those facts pre-loaded and thereby avoid loading them each time. Is this an easy thing to do? Could someone give me some pointers? Chris