# Relationship history for MSHA mine 0404071

Current hierarchy: **Vulcan Materials Company → Val-Rock Inc → SHELL CANYON 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:** O'Hair Construction Company → SHELL CANYON PIT; 1950-01-01 to 1997-06-08; source msha-controller-operator-history
- **controller_controls_mine:** O'Hair Robert H → SHELL CANYON PIT; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** O'Hair Robert H → O'Hair Construction Company; 1950-01-01 to 1997-06-08; source msha-controller-operator-history
- **controller_controls_mine:** Richard E  Becker → SHELL CANYON PIT; 1984-05-01 to 2010-12-14; source msha-controller-operator-history
- **operator_operates_mine:** Val-Rock Inc → SHELL CANYON PIT; 1997-06-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard E  Becker → Val-Rock Inc; 1997-06-09 to 2010-12-14; source msha-controller-operator-history
- **controller_controls_mine:** Vulcan Materials Company → SHELL CANYON PIT; 2010-12-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vulcan Materials Company → Val-Rock Inc; 2010-12-15 to current/open; source msha-controller-operator-history