# Relationship history for MSHA mine 4407002

Current hierarchy: **Robert H  Burton; Christopher L  Fraley → Airway Resources Llc → Fork Ridge Surface Mine**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Christopher L  Fraley et al → Fork Ridge Surface Mine; 1999-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Airway Resources Llc → Fork Ridge Surface Mine; 2000-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Christopher L  Fraley et al → Airway Resources Llc; 2000-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert H  Burton et al → Airway Resources Llc; 2000-08-01 to current/open; source msha-controller-operator-history