# Relationship history for MSHA mine 2301941

Current hierarchy: **CRH PLC → Apac-Missouri Inc → River Quarry**

- 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:** Everett Holding Co  et al → River Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Lake Ozark Construction Industries Inc → River Quarry; 1985-09-01 to 1998-11-29; source msha-controller-operator-history
- **controller_controls_operator:** Everett Holding Co  et al → Lake Ozark Construction Industries Inc; 1985-09-01 to 1998-11-29; source msha-controller-operator-history
- **controller_controls_operator:** Clarkson Construction Co et al → Lake Ozark Construction Industries Inc; 1985-09-01 to 1998-11-29; source msha-controller-operator-history
- **controller_controls_mine:** Ashland Inc → River Quarry; 1998-02-03 to 2006-08-27; source msha-controller-operator-history
- **operator_operates_mine:** Apac-Missouri Inc → River Quarry; 1998-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ashland Inc → Apac-Missouri Inc; 1998-11-30 to 2006-08-27; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → River Quarry; 2006-08-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Apac-Missouri Inc; 2006-08-28 to current/open; source msha-controller-operator-history