# Relationship history for MSHA mine 3605206

Current hierarchy: **Margaret A  Buhler → Fairview Coal Company Inc → Fairview No 1 Strip**

- 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

- **operator_operates_mine:** Fairview Coal Company Inc → Fairview No 1 Strip; 1974-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Margaret A  Buhler → Fairview No 1 Strip; 1974-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Margaret A  Buhler → Fairview Coal Company Inc; 1974-10-01 to current/open; source msha-controller-operator-history