# Relationship history for MSHA mine 0200628

Current hierarchy: **Calmat Company → Calmat Company Of Arizona → Center Street Plant #25**

- 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

- **operator_operates_mine:** Allied Concrete & Materials Company → Center Street Plant #25; 1950-01-01 to 1986-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Allied Concrete & Materials Company → Center Street Plant #25; 1950-01-01 to 1986-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Allied Concrete & Materials Company → Allied Concrete & Materials Company; 1950-01-01 to 1986-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Calmat Company → Center Street Plant #25; 1983-09-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Calmat Company Of Arizona → Center Street Plant #25; 1987-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Calmat Company → Calmat Company Of Arizona; 1987-01-01 to current/open; source msha-controller-operator-history