# Relationship history for MSHA mine 0502248

Current hierarchy: **Kofford Kay G → Emrx Corp → Logan Wash**

- 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:** Occidental Oil Shale Inc → Logan Wash; 1950-01-01 to 1988-04-17; source msha-controller-operator-history
- **controller_controls_mine:** Occidental Petroleum Corp → Logan Wash; 1950-01-01 to 1988-04-17; source msha-controller-operator-history
- **controller_controls_operator:** Occidental Petroleum Corp → Occidental Oil Shale Inc; 1950-01-01 to 1988-04-17; source msha-controller-operator-history
- **operator_operates_mine:** Emrx Corp → Logan Wash; 1988-04-18 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Kofford Kay G → Logan Wash; 1988-04-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kofford Kay G → Emrx Corp; 1988-04-18 to current/open; source msha-controller-operator-history