# Relationship history for MSHA mine 4502598

Current hierarchy: **Okanogan County-Wa → Okanogan County Road Department-Wa → Brewster State Pit No 4-8**

- 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

- **controller_controls_mine:** Okanogan County-Wa → Brewster State Pit No 4-8; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Okanogan County Road Department-Wa → Brewster State Pit No 4-8; 1978-03-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Okanogan County-Wa → Okanogan County Road Department-Wa; 1978-03-09 to current/open; source msha-controller-operator-history