Juniors and seniors only. Maybe just srs. I know girls get fast young, but preserve the chance of a race for the kids graduating.
Time qualifications to attend. Cut down dramatically on numbers who go. Tough with variable XC course and no spring track, but you have to try something.
Limit and spread out heats and heat sizes. Do a time merge for qualification.
Maybe girls and guys on different days.
They could run it with pretty low risk if they want.