# Relationship history for MSHA mine 4202424

Current hierarchy: **Don E  Richards; Roger  Brockbank → All Rock Sand & Gravel Inc → Ouray Gravel 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** JCS Construction Inc → Ouray Gravel Pit; 2005-12-15 to 2007-03-13; source msha-controller-operator-history
- **controller_controls_mine:** John  Busch  et al → Ouray Gravel Pit; 2005-12-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John  Busch  et al → JCS Construction Inc; 2005-12-15 to 2007-03-13; source msha-controller-operator-history
- **operator_operates_mine:** All Rock Sand & Gravel Inc → Ouray Gravel Pit; 2007-03-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Roger  Brockbank  et al → Ouray Gravel Pit; 2007-03-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roger  Brockbank  et al → All Rock Sand & Gravel Inc; 2007-03-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Don E  Richards  et al → All Rock Sand & Gravel Inc; 2007-03-14 to current/open; source msha-controller-operator-history