# Relationship history for MSHA mine 4300793

Current hierarchy: **Larry A  Hebert → Hebert Excavation Corporation → HEC-Norberg Metso Screen 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Hebert Excavation Corporation → HEC-Norberg Metso Screen Plant; 2018-10-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Larry A  Hebert → HEC-Norberg Metso Screen Plant; 2018-10-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Larry A  Hebert → Hebert Excavation Corporation; 2018-10-10 to current/open; source msha-controller-operator-history