# Relationship history for MSHA mine 2501199

Current hierarchy: **David L  Garrison → Garrison Sand and Gravel → Garrison Sand & Gravel/Blake**

- 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:** Garrison Sand and Gravel → Garrison Sand & Gravel/Blake; 2001-04-03 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** David L  Garrison → Garrison Sand & Gravel/Blake; 2001-04-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David L  Garrison → Garrison Sand and Gravel; 2001-04-03 to current/open; source msha-controller-operator-history