# Relationship history for MSHA mine 2302332

Current hierarchy: **Richard E  Grisham → Grisham Grading & Excavating Inc. → Rushville Quarry**

- 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:** Grisham Grading & Excavating Inc. → Rushville Quarry; 2006-04-12 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Richard E  Grisham → Rushville Quarry; 2006-04-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard E  Grisham → Grisham Grading & Excavating Inc.; 2006-04-12 to current/open; source msha-controller-operator-history