# Relationship history for MSHA mine 3605090

Current hierarchy: **Bearer Martin L → North Cambria Fuel Company → Hastings #8 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:** Bearer Martin L → Hastings #8 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Rich Hill Coal Company → Hastings #8 Mine; 1974-01-01 to 1974-06-09; source msha-controller-operator-history
- **controller_controls_mine:** Rich Hill Coal Company → Hastings #8 Mine; 1974-01-01 to 1974-06-09; source msha-controller-operator-history
- **controller_controls_operator:** Rich Hill Coal Company → Rich Hill Coal Company; 1974-01-01 to 1974-06-09; source msha-controller-operator-history
- **operator_operates_mine:** North Cambria Fuel Company → Hastings #8 Mine; 1974-06-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bearer Martin L → North Cambria Fuel Company; 1974-06-10 to current/open; source msha-controller-operator-history