# Relationship history for MSHA mine 3608509

Current hierarchy: **Kensey Lenard → Penn Run Gravel → PRG #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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Penn Run Gravel → PRG #1; 1995-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Kensey Lenard → PRG #1; 1995-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kensey Lenard → Penn Run Gravel; 1995-03-01 to current/open; source msha-controller-operator-history