# Relationship history for MSHA mine 1200632

Current hierarchy: **Ronald D  Bjustrom; Dan  Marion → Country Stone Sand & Gravel → Brand Pit**

- 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

- **operator_operates_mine:** Wilhelm Gravel Company Inc → Brand Pit; 1950-01-01 to 2003-01-01; source msha-controller-operator-history
- **controller_controls_mine:** Gerald  Wilhelm → Brand Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gerald  Wilhelm → Wilhelm Gravel Company Inc; 1950-01-01 to 2003-01-01; source msha-controller-operator-history
- **operator_operates_mine:** Country Stone Sand & Gravel → Brand Pit; 2003-01-02 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ronald D  Bjustrom et al → Brand Pit; 2003-01-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ronald D  Bjustrom et al → Country Stone Sand & Gravel; 2003-01-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dan  Marion et al → Country Stone Sand & Gravel; 2003-01-02 to current/open; source msha-controller-operator-history