# Relationship history for MSHA mine 2200688

Current hierarchy: **CRH PLC → APAC-MS INC. → Weyerhaeuser/Air Base Plant**

- 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

- **controller_controls_mine:** Ashland Inc → Weyerhaeuser/Air Base Plant; 1950-01-01 to 2006-08-27; source msha-controller-operator-history
- **controller_controls_mine:** Blain Sand & Gravel Inc → Weyerhaeuser/Air Base Plant; 1950-01-01 to 2021-12-02; source msha-controller-operator-history
- **operator_operates_mine:** Bacco Materials Inc → Weyerhaeuser/Air Base Plant; 1997-07-01 to 2023-01-10; source msha-controller-operator-history
- **controller_controls_operator:** Blain Sand & Gravel Inc → Bacco Materials Inc; 1997-07-01 to 2021-12-02; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Weyerhaeuser/Air Base Plant; 2006-08-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Weyerhaeuser/Air Base Plant; 2021-12-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Bacco Materials Inc; 2021-12-03 to 2023-01-10; source msha-controller-operator-history
- **operator_operates_mine:** APAC-MS INC. → Weyerhaeuser/Air Base Plant; 2023-01-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ashland Inc → APAC-MS INC.; 2023-01-11 to 2006-08-27; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → APAC-MS INC.; 2023-01-11 to current/open; source msha-controller-operator-history