# Relationship history for MSHA mine 0600770

Current hierarchy: **Larry A  Vaughn → STAFFORD SAND AND GRAVEL LLC → STAFFORD SAND AND GRAVEL LLC**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Stafford Sand and Gravel LLC → STAFFORD SAND AND GRAVEL LLC; 2011-05-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Larry A  Vaughn → STAFFORD SAND AND GRAVEL LLC; 2011-05-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Larry A  Vaughn → Stafford Sand and Gravel LLC; 2011-05-26 to current/open; source msha-controller-operator-history