# Relationship history for MSHA mine 2103048

Current hierarchy: **Thomas  Nemanich → Mesabi Bituminous, Inc. → Portable Crushing**

- 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

- **operator_operates_mine:** Mesabi Bituminous, Inc. → Portable Crushing; 1992-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Jerome  Nemanich → Portable Crushing; 1992-06-01 to 2015-06-16; source msha-controller-operator-history
- **controller_controls_operator:** Jerome  Nemanich → Mesabi Bituminous, Inc.; 1992-06-01 to 2015-06-16; source msha-controller-operator-history
- **controller_controls_mine:** Thomas  Nemanich → Portable Crushing; 2015-06-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thomas  Nemanich → Mesabi Bituminous, Inc.; 2015-06-17 to current/open; source msha-controller-operator-history