# Relationship history for MSHA mine 0400204

Current hierarchy: **Vulcan Materials Company → Superior Ready Mix Concrete L.P. → National Quarries**

- 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:** National Quarries Inc → National Quarries; 1950-01-01 to 2000-01-11; source msha-controller-operator-history
- **controller_controls_mine:** Michael G Johnson → National Quarries; 1950-01-01 to 2000-01-11; source msha-controller-operator-history
- **controller_controls_operator:** Michael G Johnson → National Quarries Inc; 1950-01-01 to 2000-01-11; source msha-controller-operator-history
- **controller_controls_mine:** J Brouwer Investments Inc Et Al → National Quarries; 1979-09-01 to 2025-04-27; source msha-controller-operator-history
- **operator_operates_mine:** National Quarries LLC → National Quarries; 2000-01-12 to 2011-06-30; source msha-controller-operator-history
- **controller_controls_mine:** John  Petterson → National Quarries; 2000-01-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John  Petterson → National Quarries LLC; 2000-01-12 to 2011-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Superior Ready Mix Concrete L.P. → National Quarries; 2011-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** J Brouwer Investments Inc Et Al → Superior Ready Mix Concrete L.P.; 2011-07-01 to 2025-04-27; source msha-controller-operator-history
- **controller_controls_mine:** Vulcan Materials Company → National Quarries; 2025-04-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vulcan Materials Company → Superior Ready Mix Concrete L.P.; 2025-04-28 to current/open; source msha-controller-operator-history