# Relationship history for MSHA mine 2003087

Current hierarchy: **Allan John  Zirkel → Benzie Sand & Gravel LLC → Benzie 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

- **controller_controls_mine:** Albert W  Brown → Benzie Sand and Gravel LLC; 1986-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Al Brown → Benzie Sand and Gravel LLC; 1998-10-01 to 2002-04-23; source msha-controller-operator-history
- **controller_controls_operator:** Albert W  Brown → Al Brown; 1998-10-01 to 2002-04-23; source msha-controller-operator-history
- **operator_operates_mine:** Al's Aggregate Processing → Benzie Sand and Gravel LLC; 2002-04-24 to 2024-04-09; source msha-controller-operator-history
- **controller_controls_mine:** Albert W  Brown → Benzie Sand and Gravel LLC; 2002-04-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Albert W  Brown → Al's Aggregate Processing; 2002-04-24 to 2024-04-09; source msha-controller-operator-history
- **operator_operates_mine:** Benzie Sand & Gravel LLC → Benzie Sand and Gravel LLC; 2024-04-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Allan John  Zirkel → Benzie Sand and Gravel LLC; 2024-04-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Allan John  Zirkel → Benzie Sand & Gravel LLC; 2024-04-10 to current/open; source msha-controller-operator-history