# Relationship history for MSHA mine 1511405

Current hierarchy: **Senters Harold & Clarence Senters → Big Hill Coal Company → No 2**

- 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:** Senters Harold & Clarence Senters Et Al → No 2; 1977-07-21 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Big Hill Coal Company → No 2; 1978-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Senters Harold & Clarence Senters Et Al → Big Hill Coal Company; 1978-06-01 to current/open; source msha-controller-operator-history