# Relationship history for MSHA mine 3002788

Current hierarchy: **Ronald J  Stiles → Process Sand & Gravel → Richville Pit**

- 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:** Processed Sand & Gravel → Richville Pit; 1987-05-01 to 2014-03-04; source msha-controller-operator-history
- **controller_controls_mine:** Stiles John G & Ronald J → Richville Pit; 1987-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Stiles John G & Ronald J → Processed Sand & Gravel; 1987-05-01 to 2014-03-04; source msha-controller-operator-history
- **operator_operates_mine:** Process Sand & Gravel → Richville Pit; 2014-03-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ronald J  Stiles → Richville Pit; 2014-03-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ronald J  Stiles → Process Sand & Gravel; 2014-03-05 to current/open; source msha-controller-operator-history