# Relationship history for MSHA mine 1515683

Current hierarchy: **Smith Herbert → Wildfire Coal Company → Wildfire Coal Co Mine No 3**

- 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:** Wildfire Coal Company → Wildfire Coal Co Mine No 3; 1986-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Smith Herbert → Wildfire Coal Co Mine No 3; 1986-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Smith Herbert → Wildfire Coal Company; 1986-07-01 to current/open; source msha-controller-operator-history