# Relationship history for MSHA mine 2003288

Current hierarchy: **Daniel R  Balkema; Ralph T  Balkema → Aggregate Resources, Inc. → Portable Plant #101**

- 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:** Daniel R  Balkema et al → Portable Plant #101; 2002-01-02 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Aggregate Resources, Inc. → Portable Plant #101; 2004-01-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Daniel R  Balkema et al → Aggregate Resources, Inc.; 2004-01-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ralph T  Balkema et al → Aggregate Resources, Inc.; 2004-01-12 to current/open; source msha-controller-operator-history