# Relationship history for MSHA mine 2601706

Current hierarchy: **Thompson Charles M → Basic Rock & Sand → White Rock Five Pit & Mill**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Basic Rock & Sand → White Rock Five Pit & Mill; 1981-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Thompson Charles M → White Rock Five Pit & Mill; 1981-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thompson Charles M → Basic Rock & Sand; 1981-01-01 to current/open; source msha-controller-operator-history