# Relationship history for MSHA mine 1509804

Current hierarchy: **Bow Valley Industries Ltd → Harlan Fuel Company → No 10**

- 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:** Goldfield Corp → No 10; 1975-03-13 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Harlan Fuel Company → No 10; 1976-06-28 to 1982-02-21; source msha-controller-operator-history
- **controller_controls_operator:** Goldfield Corp → Harlan Fuel Company; 1976-06-28 to 1982-02-21; source msha-controller-operator-history
- **operator_operates_mine:** Harlan Fuel Company → No 10; 1982-02-22 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bow Valley Industries Ltd → No 10; 1982-02-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bow Valley Industries Ltd → Harlan Fuel Company; 1982-02-22 to current/open; source msha-controller-operator-history