# Relationship history for MSHA mine 3700203

Current hierarchy: **Debra A  Mc Allister; David J  Skurka → D &  D Construction Co Inc → Coventry Pit**

- 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:** D &  D Construction Co Inc → Coventry Pit; 2007-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Debra A  Mc Allister  et al → Coventry Pit; 2007-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Debra A  Mc Allister  et al → D &  D Construction Co Inc; 2007-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David J  Skurka  et al → D &  D Construction Co Inc; 2007-11-30 to current/open; source msha-controller-operator-history