# Relationship history for MSHA mine 2104097

Current hierarchy: **Scott  Wirtjes → Alexandria Gravel Products LLC → Plant #4**

- 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:** Scott  Wirtjes → Plant #4; 2011-03-31 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Alexandria Gravel Products LLC → Plant #4; 2025-05-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Scott  Wirtjes → Alexandria Gravel Products LLC; 2025-05-02 to current/open; source msha-controller-operator-history