# Relationship history for MSHA mine 1301302

Current hierarchy: **Zechariah P Norgaard; Peter H Norgaard; Rosemary G Norgaard → NSG, LLC → NORGAARD SAND & GRAVEL**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** NORGAARD SAND & GRAVEL → NORGAARD SAND & GRAVEL; 1950-01-01 to 2017-12-04; source msha-controller-operator-history
- **controller_controls_mine:** Peter H Norgaard → NORGAARD SAND & GRAVEL; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Peter H Norgaard → NORGAARD SAND & GRAVEL; 1950-01-01 to 2017-12-04; source msha-controller-operator-history
- **operator_operates_mine:** NSG, LLC → NORGAARD SAND & GRAVEL; 2017-12-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Peter H Norgaard et al → NORGAARD SAND & GRAVEL; 2017-12-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Peter H Norgaard et al → NSG, LLC; 2017-12-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Zechariah P Norgaard et al → NSG, LLC; 2017-12-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rosemary G Norgaard et al → NSG, LLC; 2017-12-05 to current/open; source msha-controller-operator-history