# Relationship history for MSHA mine 4104108

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials Southwest LLC → Smithson Valley 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 → Smithson Valley Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Olmos Contracting 1, LLC → Smithson Valley Quarry; 1999-10-01 to 2017-06-15; source msha-controller-operator-history
- **controller_controls_mine:** Hugh E Long → Smithson Valley Quarry; 1999-10-01 to 2013-07-28; source msha-controller-operator-history
- **controller_controls_operator:** Hugh E Long → Olmos Contracting 1, LLC; 1999-10-01 to 2013-07-28; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Smithson Valley Quarry; 2007-11-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Larry D  Struthoff → Smithson Valley Quarry; 2013-07-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Larry D  Struthoff → Olmos Contracting 1, LLC; 2013-07-29 to 2017-06-15; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials Inc → Smithson Valley Quarry; 2017-06-16 to 2024-04-20; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials Inc; 2017-06-16 to 2024-04-20; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials Southwest LLC → Smithson Valley Quarry; 2024-04-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials Southwest LLC; 2024-04-21 to current/open; source msha-controller-operator-history