You can find the Chippenham Harriers Club Championship Rules here in PDF format. These rules will be applied from 2022 onwards.
The detailed rules in the link, but here is a quick summary:
• Four Championship categories
• Score based on position to other Harriers (start at 30 pts, min 5 pts)
• Best race scores accumulated (drop worst two scores)
• Selected races from WRRL, WORL plus parkrun
• Prizes for category winners