# Relationship history for MSHA mine 3400617

Current hierarchy: **Campbell Jo Anna → Nova Sand Company Inc → Crum Pit**

- 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:** Shoffner Larry E → Crum Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** J & J Sand Company → Crum Pit; 1950-01-01 to 1983-10-25; source msha-controller-operator-history
- **controller_controls_mine:** John Fred Jr → Crum Pit; 1950-01-01 to 1983-10-25; source msha-controller-operator-history
- **controller_controls_operator:** John Fred Jr → J & J Sand Company; 1950-01-01 to 1983-10-25; source msha-controller-operator-history
- **operator_operates_mine:** Shoffner Sand Of Oklahoma Inc → Crum Pit; 1983-10-26 to 1990-07-22; source msha-controller-operator-history
- **controller_controls_operator:** Shoffner Larry E → Shoffner Sand Of Oklahoma Inc; 1983-10-26 to 1990-07-22; source msha-controller-operator-history
- **operator_operates_mine:** Nova Sand Company Inc → Crum Pit; 1990-07-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Campbell Jo Anna → Crum Pit; 1990-07-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Campbell Jo Anna → Nova Sand Company Inc; 1990-07-23 to current/open; source msha-controller-operator-history