# Relationship history for MSHA mine 0901069

Current hierarchy: **Alberty Nathan E → South Georgia Rock & Materials Inc → GRADY 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:** Grady Aggregates Corp → GRADY QUARRY; 1992-12-01 to 1995-07-09; source msha-controller-operator-history
- **controller_controls_mine:** Kuhlken John P & Ray Rouse Iii → GRADY QUARRY; 1992-12-01 to 1995-07-09; source msha-controller-operator-history
- **controller_controls_operator:** Kuhlken John P & Ray Rouse Iii → Grady Aggregates Corp; 1992-12-01 to 1995-07-09; source msha-controller-operator-history
- **operator_operates_mine:** South Georgia Rock & Materials Inc → GRADY QUARRY; 1995-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Alberty Nathan E Et Al → GRADY QUARRY; 1995-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alberty Nathan E Et Al → South Georgia Rock & Materials Inc; 1995-07-10 to current/open; source msha-controller-operator-history