# Relationship history for MSHA mine 4103637

Current hierarchy: **Zachary  Tausch; Vernon  Tausch → Medina Crushed Stone → Portable Rock Crushing Plant #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

- **controller_controls_mine:** Alma  Tausch → Portable Rock Crushing Plant #1; 1990-02-01 to 2009-10-29; source msha-controller-operator-history
- **operator_operates_mine:** Medina Crushed Stone → Portable Rock Crushing Plant #1; 1990-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alma  Tausch → Medina Crushed Stone; 1990-10-01 to 2009-10-29; source msha-controller-operator-history
- **controller_controls_mine:** Vernon  Tausch  et al → Portable Rock Crushing Plant #1; 2009-10-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vernon  Tausch  et al → Medina Crushed Stone; 2009-10-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Zachary  Tausch  et al → Medina Crushed Stone; 2009-10-30 to current/open; source msha-controller-operator-history