# Relationship history for MSHA mine 3800757

Current hierarchy: **Quikrete Holdings Inc. → American Materials Company LLC → Andrews 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:** Gary (Tim)  Bizzell  et al → Andrews Quarry; 1999-11-02 to 2016-02-04; source msha-controller-operator-history
- **controller_controls_mine:** Summit Materials LLC → Andrews Quarry; 2016-02-05 to 2025-08-03; source msha-controller-operator-history
- **operator_operates_mine:** American Materials Company LLC → Andrews Quarry; 2020-08-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Summit Materials LLC → American Materials Company LLC; 2020-08-28 to 2025-08-03; source msha-controller-operator-history
- **controller_controls_operator:** Gary (Tim)  Bizzell  et al → American Materials Company LLC; 2020-08-28 to 2016-02-04; source msha-controller-operator-history
- **controller_controls_mine:** Quikrete Holdings Inc. → Andrews Quarry; 2025-08-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Quikrete Holdings Inc. → American Materials Company LLC; 2025-08-04 to current/open; source msha-controller-operator-history