# Relationship history for MSHA mine 3503345

Current hierarchy: **Dan E  Hooker → Harney Rock & Paving Company → North Powder Quarry Crusher #1**

- 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:** Dan E  Hooker → North Powder Quarry Crusher #1; 1979-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Harney Rock & Paving Company → North Powder Quarry Crusher #1; 1990-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dan E  Hooker → Harney Rock & Paving Company; 1990-05-01 to current/open; source msha-controller-operator-history