# Relationship history for MSHA mine 0202166

Current hierarchy: **Vulcan Materials Company → CalMat Co → West 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Calmat Company → West Plant; 1983-09-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** U S Rock → West Plant; 1983-09-01 to 1985-12-01; source msha-controller-operator-history
- **controller_controls_mine:** Al  Bader → West Plant; 1983-09-01 to 1985-12-01; source msha-controller-operator-history
- **controller_controls_operator:** Al  Bader → U S Rock; 1983-09-01 to 1985-12-01; source msha-controller-operator-history
- **operator_operates_mine:** Calmat Company Of Arizona → West Plant; 1985-12-02 to 1999-01-05; source msha-controller-operator-history
- **controller_controls_operator:** Calmat Company → Calmat Company Of Arizona; 1985-12-02 to 1999-01-05; source msha-controller-operator-history
- **operator_operates_mine:** Calmat Company Of Arizona → West Plant; 1999-01-06 to 2004-01-06; source msha-controller-operator-history
- **controller_controls_mine:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → West Plant; 1999-01-06 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_operator:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → Calmat Company Of Arizona; 1999-01-06 to 2004-01-06; source msha-controller-operator-history
- **operator_operates_mine:** CalMat Co → West Plant; 2004-01-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → CalMat Co; 2004-01-07 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_mine:** Vulcan Materials Company → West Plant; 2007-11-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vulcan Materials Company → Calmat Company Of Arizona; 2007-11-16 to 2004-01-06; source msha-controller-operator-history
- **controller_controls_operator:** Vulcan Materials Company → CalMat Co; 2007-11-16 to current/open; source msha-controller-operator-history