# Relationship history for MSHA mine 1512965

Current hierarchy: **Collins Stephen D → Mell Coal Corp → No 1 Surface 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Mell Coal Corp → No 1 Surface Mine; 1981-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Collins Stephen D → No 1 Surface Mine; 1981-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Collins Stephen D → Mell Coal Corp; 1981-06-01 to current/open; source msha-controller-operator-history