# Relationship history for MSHA mine 2700321

Current hierarchy: **Greg A  Sanborn → Rumney Sand & Gravel → Rumney Sand & Gravel**

- 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:** Rumney Sand & Gravel → Rumney Sand & Gravel; 1996-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Greg A  Sanborn → Rumney Sand & Gravel; 1996-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Greg A  Sanborn → Rumney Sand & Gravel; 1996-10-01 to current/open; source msha-controller-operator-history