# Relationship history for MSHA mine 3605630

Current hierarchy: **Klouser Robert H & James H Maurer → M & K Coal Company → Buck Mtn Tunnel**

- 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:** R K & S Coal Company → Buck Mtn Tunnel; 1950-01-01 to 1977-01-24; source msha-controller-operator-history
- **controller_controls_mine:** Klouser Robert H & Robert Rada → Buck Mtn Tunnel; 1950-01-01 to 1977-01-24; source msha-controller-operator-history
- **controller_controls_operator:** Klouser Robert H & Robert Rada → R K & S Coal Company; 1950-01-01 to 1977-01-24; source msha-controller-operator-history
- **operator_operates_mine:** M & K Coal Company → Buck Mtn Tunnel; 1977-01-25 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Klouser Robert H & James H Maurer → Buck Mtn Tunnel; 1977-01-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Klouser Robert H & James H Maurer → M & K Coal Company; 1977-01-25 to current/open; source msha-controller-operator-history