# Relationship history for MSHA mine 2601363

Current hierarchy: **Bee Bee Contractors → Washoe Rock Products → Washoe Rock Products 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:** Western Aggregates Inc → Washoe Rock Products Pit; 1950-01-01 to 1984-07-29; source msha-controller-operator-history
- **controller_controls_mine:** Eagle Materials Inc → Washoe Rock Products Pit; 1950-01-01 to 2020-04-16; source msha-controller-operator-history
- **controller_controls_operator:** Eagle Materials Inc → Western Aggregates Inc; 1950-01-01 to 1984-07-29; source msha-controller-operator-history
- **operator_operates_mine:** Washoe Rock Products → Washoe Rock Products Pit; 1984-07-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bee Bee Contractors → Washoe Rock Products Pit; 1984-07-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bee Bee Contractors → Washoe Rock Products; 1984-07-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Teichert Inc → Washoe Rock Products Pit; 2020-04-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Teichert Inc → Western Aggregates Inc; 2020-04-17 to 1984-07-29; source msha-controller-operator-history