# Relationship history for MSHA mine 1512100

Current hierarchy: **Holt Edwin N → Southern Coal Reserves Inc → Surface #8**

- 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:** Holt Edwin N → Surface #8; 1978-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Southern Coal Reserves Inc → Surface #8; 1979-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Holt Edwin N → Southern Coal Reserves Inc; 1979-10-01 to current/open; source msha-controller-operator-history