# Relationship history for MSHA mine 1518910

Current hierarchy: **Christina J  Whittaker → W & F Contract Augering Inc → W & F Contract Augering Inc**

- 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

- **controller_controls_mine:** Frank  Parks → W & F Contract Augering Inc; 1998-07-01 to 2010-09-22; source msha-controller-operator-history
- **operator_operates_mine:** W & F Contract Augering Inc → W & F Contract Augering Inc; 2005-08-05 to 2010-09-22; source msha-controller-operator-history
- **controller_controls_operator:** Frank  Parks → W & F Contract Augering Inc; 2005-08-05 to 2010-09-22; source msha-controller-operator-history
- **controller_controls_mine:** Christina J  Whittaker → W & F Contract Augering Inc; 2010-09-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Christina J  Whittaker → W & F Contract Augering Inc; 2010-09-23 to 2010-09-22; source msha-controller-operator-history
- **operator_operates_mine:** W & F Contract Augering Inc → W & F Contract Augering Inc; 2010-09-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Christina J  Whittaker → W & F Contract Augering Inc; 2010-09-23 to current/open; source msha-controller-operator-history