# Relationship history for MSHA mine 4104139

Current hierarchy: **Art  Lopez → River City Ready Mix, Inc. → River City Ready Mix, Inc.**

- 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:** Elizabeth Martinez → River City Ready Mix, Inc.; 2000-02-01 to 2000-06-30; source msha-controller-operator-history
- **controller_controls_mine:** Elizabeth E  Martinez → River City Ready Mix, Inc.; 2000-02-01 to 2000-06-30; source msha-controller-operator-history
- **controller_controls_operator:** Elizabeth E  Martinez → Elizabeth Martinez; 2000-02-01 to 2000-06-30; source msha-controller-operator-history
- **operator_operates_mine:** River City Ready Mix, Inc. → River City Ready Mix, Inc.; 2000-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Art  Lopez → River City Ready Mix, Inc.; 2000-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Art  Lopez → River City Ready Mix, Inc.; 2000-07-01 to current/open; source msha-controller-operator-history