# Relationship history for MSHA mine 2602436

Current hierarchy: **Wallis A Munger → Mungers Backhoe Service → MUNGERS BACKHOE GRAVEL 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:** Mungers Backhoe Service → MUNGERS BACKHOE GRAVEL PIT; 2000-10-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Wallis A Munger → MUNGERS BACKHOE GRAVEL PIT; 2000-10-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wallis A Munger → Mungers Backhoe Service; 2000-10-13 to current/open; source msha-controller-operator-history