# Relationship history for MSHA mine 2601721

Current hierarchy: **Mc Griffin Ken → Ken Mc Griffin → Willow Creek Operation**

- 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:** Willow Creek Placer Inc → Willow Creek Operation; 1981-03-01 to 1983-06-21; source msha-controller-operator-history
- **controller_controls_mine:** Jenks Don A → Willow Creek Operation; 1981-03-01 to 1983-06-21; source msha-controller-operator-history
- **controller_controls_operator:** Jenks Don A → Willow Creek Placer Inc; 1981-03-01 to 1983-06-21; source msha-controller-operator-history
- **operator_operates_mine:** Ro-Mac Inc → Willow Creek Operation; 1983-06-22 to 1983-08-04; source msha-controller-operator-history
- **controller_controls_mine:** Ro-Mac Inc → Willow Creek Operation; 1983-06-22 to 1983-08-04; source msha-controller-operator-history
- **controller_controls_operator:** Ro-Mac Inc → Ro-Mac Inc; 1983-06-22 to 1983-08-04; source msha-controller-operator-history
- **operator_operates_mine:** Ken Mc Griffin → Willow Creek Operation; 1983-08-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mc Griffin Ken → Willow Creek Operation; 1983-08-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mc Griffin Ken → Ken Mc Griffin; 1983-08-05 to current/open; source msha-controller-operator-history