# Relationship history for MSHA mine 2902476

Current hierarchy: **Michael  Shavers → Mesa Sand and Gravel, Inc. → Mesa Sand and Gravel Pit 1**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Mesa Sand and Gravel, Inc. → Mesa Sand and Gravel Pit 1; 2017-08-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Michael  Shavers → Mesa Sand and Gravel Pit 1; 2017-08-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael  Shavers → Mesa Sand and Gravel, Inc.; 2017-08-23 to current/open; source msha-controller-operator-history