# Relationship history for MSHA mine 1901216

Current hierarchy: **George F  Rousseau; John F  Sarao → The Materials Group of Merrimack LLC → Jungle Road 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

- **operator_operates_mine:** The Materials Group of Merrimack LLC → Jungle Road Quarry; 2012-02-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John F  Sarao et al → Jungle Road Quarry; 2012-02-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John F  Sarao et al → The Materials Group of Merrimack LLC; 2012-02-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** George F  Rousseau et al → The Materials Group of Merrimack LLC; 2012-02-14 to current/open; source msha-controller-operator-history