# Relationship history for MSHA mine 1513750

Current hierarchy: **Williams Eugene → Wilcoal Mining Inc → Mine No 1**

- 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:** Stacey Roger L → Mine No 1; 1979-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** West Virginia Solid Energy Inc → Mine No 1; 1982-10-01 to 1990-04-17; source msha-controller-operator-history
- **controller_controls_operator:** Stacey Roger L → West Virginia Solid Energy Inc; 1982-10-01 to 1990-04-17; source msha-controller-operator-history
- **operator_operates_mine:** Wilcoal Mining Inc → Mine No 1; 1990-04-18 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Williams Eugene → Mine No 1; 1990-04-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Williams Eugene → Wilcoal Mining Inc; 1990-04-18 to current/open; source msha-controller-operator-history