# Relationship history for MSHA mine 3101982

Current hierarchy: **Barnhill Contracting Company → Barnhill Contracting Co → Nicholson Sand Mine**

- 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

- **controller_controls_mine:** Barnhill Contracting Company → Nicholson Sand Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Beacham Mike A → Nicholson Sand Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Outer Banks Contractors Inc → Nicholson Sand Mine; 1985-07-01 to 1993-04-05; source msha-controller-operator-history
- **controller_controls_operator:** Beacham Mike A → Outer Banks Contractors Inc; 1985-07-01 to 1993-04-05; source msha-controller-operator-history
- **operator_operates_mine:** Barnhill Contracting Co → Nicholson Sand Mine; 1993-04-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Barnhill Contracting Company → Barnhill Contracting Co; 1993-04-06 to current/open; source msha-controller-operator-history