# Relationship history for MSHA mine 4002507

Current hierarchy: **Tipton Russell → Tipton Sand & Gravel → Piney Creek Mine And Mill**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Spring City Sand & Gravel Company → Piney Creek Mine And Mill; 1950-01-01 to 1981-01-08; source msha-controller-operator-history
- **controller_controls_mine:** Moss Enman → Piney Creek Mine And Mill; 1950-01-01 to 1981-01-08; source msha-controller-operator-history
- **controller_controls_operator:** Moss Enman → Spring City Sand & Gravel Company; 1950-01-01 to 1981-01-08; source msha-controller-operator-history
- **operator_operates_mine:** Tipton Sand & Gravel → Piney Creek Mine And Mill; 1981-01-09 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Tipton Russell → Piney Creek Mine And Mill; 1981-01-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tipton Russell → Tipton Sand & Gravel; 1981-01-09 to current/open; source msha-controller-operator-history