# Relationship history for MSHA mine 4201907

Current hierarchy: **Granite Construction Inc → Bear River Contractors → U-DOT 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Rogers Construction Company → U-DOT PIT; 1985-01-01 to 1989-08-31; source msha-controller-operator-history
- **controller_controls_mine:** Curtis  Rogers et al → U-DOT PIT; 1985-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Curtis  Rogers et al → Rogers Construction Company; 1985-01-01 to 1989-08-31; source msha-controller-operator-history
- **operator_operates_mine:** Bear River Contractors → U-DOT PIT; 1989-09-01 to 1995-08-31; source msha-controller-operator-history
- **controller_controls_mine:** Gibbons Companies → U-DOT PIT; 1989-09-01 to 1995-08-31; source msha-controller-operator-history
- **controller_controls_operator:** Gibbons Companies → Bear River Contractors; 1989-09-01 to 1995-08-31; source msha-controller-operator-history
- **operator_operates_mine:** Bear River Contractors → U-DOT PIT; 1995-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Granite Construction Inc → U-DOT PIT; 1995-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Granite Construction Inc → Bear River Contractors; 1995-09-01 to current/open; source msha-controller-operator-history