# Relationship history for MSHA mine 1700490

Current hierarchy: **David R  Kincaid → Churchill Sand and Gravel → Churchill Sand and 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:** Warren & Kincaid Corp → Churchill Sand and Gravel; 1979-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** David R  Kincaid → Churchill Sand and Gravel; 1979-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David R  Kincaid → Warren & Kincaid Corp; 1979-01-01 to current/open; source msha-controller-operator-history