# Relationship history for MSHA mine 1102264

Current hierarchy: **Howard  Wilke → Hampshire Sand & Gravel Inc → HAMPSHIRE SAND & GRAVEL INC.**

- 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:** D & Z Transfer Inc → HAMPSHIRE SAND & GRAVEL INC.; 1950-01-01 to 1998-08-09; source msha-controller-operator-history
- **controller_controls_mine:** Norman  Zimmerman → HAMPSHIRE SAND & GRAVEL INC.; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Norman  Zimmerman → D & Z Transfer Inc; 1950-01-01 to 1998-08-09; source msha-controller-operator-history
- **controller_controls_mine:** Howard  Wilke → HAMPSHIRE SAND & GRAVEL INC.; 1997-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Hampshire Sand & Gravel Inc → HAMPSHIRE SAND & GRAVEL INC.; 1998-08-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Howard  Wilke → Hampshire Sand & Gravel Inc; 1998-08-10 to current/open; source msha-controller-operator-history