# Relationship history for MSHA mine 4500670

Current hierarchy: **Walt  Miles → Miles Sand & Gravel Company → Lacey**

- 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

- **controller_controls_mine:** Walt  Miles et al → Lacey; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Olympia Sand & Gravel Company → Lacey; 1950-01-01 to 2002-01-17; source msha-controller-operator-history
- **controller_controls_mine:** Gordon B Willie et al → Lacey; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gordon B Willie et al → Olympia Sand & Gravel Company; 1950-01-01 to 2002-01-17; source msha-controller-operator-history
- **operator_operates_mine:** Miles Sand & Gravel Company → Lacey; 2002-01-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Walt  Miles et al → Miles Sand & Gravel Company; 2002-01-18 to current/open; source msha-controller-operator-history