# Relationship history for MSHA mine 1400126

Current hierarchy: **Summit Materials LLC → Cornejo & Sons LLC → Augusta Quarry**

- 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:** Martin Marietta Materials Inc → Augusta Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** David S  Walker → Augusta Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** George M Myers Inc → Augusta Quarry; 1950-01-01 to 1998-11-17; source msha-controller-operator-history
- **controller_controls_mine:** George Marc  Myers → Augusta Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** George Marc  Myers → George M Myers Inc; 1950-01-01 to 1998-11-17; source msha-controller-operator-history
- **operator_operates_mine:** Walker Stone Company Inc → Augusta Quarry; 1998-11-18 to 2001-08-02; source msha-controller-operator-history
- **controller_controls_operator:** David S  Walker → Walker Stone Company Inc; 1998-11-18 to 2001-08-02; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Aggregates → Augusta Quarry; 2001-08-03 to 2005-05-23; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 2001-08-03 to 2005-05-23; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials, Inc. → Augusta Quarry; 2005-05-24 to 2020-07-02; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials, Inc.; 2005-05-24 to 2020-07-02; source msha-controller-operator-history
- **controller_controls_mine:** Summit Materials LLC → Augusta Quarry; 2011-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Cornejo & Sons LLC → Augusta Quarry; 2020-07-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Summit Materials LLC → Cornejo & Sons LLC; 2020-07-03 to current/open; source msha-controller-operator-history