# Relationship history for MSHA mine 2501286

Current hierarchy: **Zachary  Richards; Beau  Richards → Richards Gravel Pit → Peterson 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:** Richards Gravel Pit → Peterson Pit; 2012-08-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Derek  Richards et al → Peterson Pit; 2012-08-13 to 2024-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Derek  Richards et al → Richards Gravel Pit; 2012-08-13 to 2024-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Alicia  Richards et al → Richards Gravel Pit; 2012-08-13 to 2024-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Zachary  Richards et al → Peterson Pit; 2025-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Zachary  Richards et al → Richards Gravel Pit; 2025-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Beau  Richards et al → Richards Gravel Pit; 2025-01-01 to current/open; source msha-controller-operator-history