# Relationship history for MSHA mine 4104734

Current hierarchy: **Arcosa, Inc → Trinity Materials, Inc. → Silver Plant 1546**

- 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:** Trinity Industries Inc → Silver Plant 1546; 1991-12-01 to 2018-10-31; source msha-controller-operator-history
- **operator_operates_mine:** Trinity Materials, Inc. → Silver Plant 1546; 2008-06-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Trinity Industries Inc → Trinity Materials, Inc.; 2008-06-10 to 2018-10-31; source msha-controller-operator-history
- **controller_controls_mine:** Arcosa, Inc → Silver Plant 1546; 2018-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Arcosa, Inc → Trinity Materials, Inc.; 2018-11-01 to current/open; source msha-controller-operator-history