# Relationship history for MSHA mine 0503970

Current hierarchy: **Warren O  Wilcox → Gunnison Gravel & Earth Moving LLC → Dickerson Pit**

- 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:** Formaz & Son Inc → Dickerson Pit; 1984-07-01 to 1989-08-27; source msha-controller-operator-history
- **controller_controls_mine:** Formaz Richard & Lewis → Dickerson Pit; 1984-07-01 to 1989-08-27; source msha-controller-operator-history
- **controller_controls_operator:** Formaz Richard & Lewis → Formaz & Son Inc; 1984-07-01 to 1989-08-27; source msha-controller-operator-history
- **operator_operates_mine:** Wilcox Dozer Service → Dickerson Pit; 1989-08-28 to 2011-12-08; source msha-controller-operator-history
- **controller_controls_mine:** Warren O  Wilcox → Dickerson Pit; 1989-08-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Warren O  Wilcox → Wilcox Dozer Service; 1989-08-28 to 2011-12-08; source msha-controller-operator-history
- **operator_operates_mine:** Gunnison Gravel & Earth Moving LLC → Dickerson Pit; 2011-12-09 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Warren O  Wilcox → Dickerson Pit; 2011-12-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Warren O  Wilcox → Gunnison Gravel & Earth Moving LLC; 2011-12-09 to current/open; source msha-controller-operator-history