# Relationship history for MSHA mine 1515177

Current hierarchy: **Daniels Larry V-Ronnie Williamson → Drell Coal Company → No 1 Strip**

- 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:** Drell Coal Company → No 1 Strip; 1985-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Daniels Larry V-Ronnie Williamson Et Al → No 1 Strip; 1985-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Daniels Larry V-Ronnie Williamson Et Al → Drell Coal Company; 1985-04-01 to current/open; source msha-controller-operator-history