# Relationship history for MSHA mine 0300607

Current hierarchy: **Darrell E  Hayden → Hayden'S Gravel & Construction → Hayden'S Gravel 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** S & S Gravel Company → Hayden'S Gravel Pit; 1950-01-01 to 1985-08-06; source msha-controller-operator-history
- **controller_controls_mine:** Stahl I V & Neala → Hayden'S Gravel Pit; 1950-01-01 to 1985-08-06; source msha-controller-operator-history
- **controller_controls_operator:** Stahl I V & Neala → S & S Gravel Company; 1950-01-01 to 1985-08-06; source msha-controller-operator-history
- **operator_operates_mine:** Hayden'S Gravel & Construction → Hayden'S Gravel Pit; 1985-08-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Darrell E  Hayden → Hayden'S Gravel Pit; 1985-08-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Darrell E  Hayden → Hayden'S Gravel & Construction; 1985-08-07 to current/open; source msha-controller-operator-history