# Relationship history for MSHA mine 1901038

Current hierarchy: **John E MacDonald → Newbury Trucking Service Inc → MASTER KRUSH PORTABLE**

- 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:** Newbury Trucking Service Inc → MASTER KRUSH PORTABLE; 1993-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John E MacDonald → MASTER KRUSH PORTABLE; 1993-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John E MacDonald → Newbury Trucking Service Inc; 1993-03-01 to current/open; source msha-controller-operator-history