# Relationship history for MSHA mine 2003164

Current hierarchy: **Oscoda County-Mi → Oscoda County Road Commission → OCRC Portable Sand Screen**

- 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:** Oscoda County Road Commission → OCRC Portable Sand Screen; 2000-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Oscoda County-Mi → OCRC Portable Sand Screen; 2000-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Oscoda County-Mi → Oscoda County Road Commission; 2000-07-01 to current/open; source msha-controller-operator-history