# Relationship history for MSHA mine 0500977

Current hierarchy: **CRH PLC → Oldcastle SW Group, Inc → Mackenzie 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:** Fremont Paving Inc → Mackenzie Pit; 1950-01-01 to 1981-05-11; source msha-controller-operator-history
- **controller_controls_mine:** Bryan Wayman → Mackenzie Pit; 1950-01-01 to 1981-05-11; source msha-controller-operator-history
- **controller_controls_operator:** Bryan Wayman → Fremont Paving Inc; 1950-01-01 to 1981-05-11; source msha-controller-operator-history
- **operator_operates_mine:** Fremont Paving & Redi-Mix Inc → Mackenzie Pit; 1981-05-12 to 2024-07-18; source msha-controller-operator-history
- **controller_controls_mine:** John L  Ary → Mackenzie Pit; 1981-05-12 to 2006-04-04; source msha-controller-operator-history
- **controller_controls_operator:** John L  Ary → Fremont Paving & Redi-Mix Inc; 1981-05-12 to 2006-04-04; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Mackenzie Pit; 1998-01-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John P  Ary → Mackenzie Pit; 2006-04-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John P  Ary → Fremont Paving & Redi-Mix Inc; 2006-04-05 to 2024-07-18; source msha-controller-operator-history
- **operator_operates_mine:** Oldcastle SW Group, Inc → Mackenzie Pit; 2024-07-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Oldcastle SW Group, Inc; 2024-07-19 to current/open; source msha-controller-operator-history