# Relationship history for MSHA mine 3901214

Current hierarchy: **Peters Ronald → Peters Graveling → Unit No 1**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Harolds Gravel → Unit No 1; 1979-01-01 to 1979-12-10; source msha-controller-operator-history
- **controller_controls_mine:** Berner Harold → Unit No 1; 1979-01-01 to 1979-12-10; source msha-controller-operator-history
- **controller_controls_operator:** Berner Harold → Harolds Gravel; 1979-01-01 to 1979-12-10; source msha-controller-operator-history
- **controller_controls_mine:** Peters Ronald → Unit No 1; 1979-09-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Peters Graveling → Unit No 1; 1979-12-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Peters Ronald → Peters Graveling; 1979-12-11 to current/open; source msha-controller-operator-history