# Relationship history for MSHA mine 3401067

Current hierarchy: **Woody R E → R E Woody & Sons Steel Preservation → R E Woody And Sons Sand & Gravel**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** H & W Sand & Gravel → R E Woody And Sons Sand & Gravel; 1950-01-01 to 1979-08-31; source msha-controller-operator-history
- **controller_controls_mine:** Walton Sid & Jeff Harris → R E Woody And Sons Sand & Gravel; 1950-01-01 to 1979-08-31; source msha-controller-operator-history
- **controller_controls_operator:** Walton Sid & Jeff Harris → H & W Sand & Gravel; 1950-01-01 to 1979-08-31; source msha-controller-operator-history
- **operator_operates_mine:** R E Woody & Sons Steel Preservation → R E Woody And Sons Sand & Gravel; 1979-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Woody R E → R E Woody And Sons Sand & Gravel; 1979-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Woody R E → R E Woody & Sons Steel Preservation; 1979-09-01 to current/open; source msha-controller-operator-history