# Relationship history for MSHA mine 4103768

Current hierarchy: **Elizabeth E  Martinez → EM Sand Pit → EM Sand 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

- **controller_controls_mine:** Pete  Gallegos Sr → EM Sand Pit; 1992-11-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Big Buck Asphalt Inc → EM Sand Pit; 1993-05-01 to 1998-07-20; source msha-controller-operator-history
- **controller_controls_operator:** Pete  Gallegos Sr → Big Buck Asphalt Inc; 1993-05-01 to 1998-07-20; source msha-controller-operator-history
- **operator_operates_mine:** EM Sand Pit → EM Sand Pit; 1998-07-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cesar  Martinez → EM Sand Pit; 1998-07-21 to 2004-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Cesar  Martinez → EM Sand Pit; 1998-07-21 to 2004-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Elizabeth E  Martinez → EM Sand Pit; 2005-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Elizabeth E  Martinez → EM Sand Pit; 2005-01-01 to current/open; source msha-controller-operator-history