# Relationship history for MSHA mine 1512797

Current hierarchy: **Martin Arnold → Eagle Rock Coal Corp → Highsplint No 1 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

- **operator_operates_mine:** Verda Coal Sales/Bon Trucking Company → Highsplint No 1 Mine; 1981-03-01 to 1982-09-12; source msha-controller-operator-history
- **controller_controls_mine:** Harvey  Napier → Highsplint No 1 Mine; 1981-03-01 to 1982-09-12; source msha-controller-operator-history
- **controller_controls_operator:** Harvey  Napier → Verda Coal Sales/Bon Trucking Company; 1981-03-01 to 1982-09-12; source msha-controller-operator-history
- **operator_operates_mine:** Eagle Rock Coal Corp → Highsplint No 1 Mine; 1982-09-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Martin Arnold → Highsplint No 1 Mine; 1982-09-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Arnold → Eagle Rock Coal Corp; 1982-09-13 to current/open; source msha-controller-operator-history