# Relationship history for MSHA mine 3002826

Current hierarchy: **Northeast Slate Incorporated → Hilltop Slate Inc → Hatch Hill Quarry**

- 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:** Alfred Mc Alpine Inc → Hatch Hill Quarry; 1986-03-04 to 2008-01-15; source msha-controller-operator-history
- **operator_operates_mine:** Hilltop Slate Inc → Hatch Hill Quarry; 1987-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alfred Mc Alpine Inc → Hilltop Slate Inc; 1987-12-01 to 2008-01-15; source msha-controller-operator-history
- **controller_controls_mine:** Northeast Slate Incorporated → Hatch Hill Quarry; 2008-01-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Northeast Slate Incorporated → Hilltop Slate Inc; 2008-01-16 to current/open; source msha-controller-operator-history