# Relationship history for MSHA mine 1400895

Current hierarchy: **Ben G  Kates → Kaw Valley Sand and Gravel, Inc. → Turner Dry Sand Plant**

- 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:** Stewart Sand & Material Company → Turner Dry Sand Plant; 1950-01-01 to 1978-03-22; source msha-controller-operator-history
- **controller_controls_mine:** Stewart Sand & Material Company → Turner Dry Sand Plant; 1950-01-01 to 1979-07-31; source msha-controller-operator-history
- **controller_controls_operator:** Stewart Sand & Material Company → Stewart Sand & Material Company; 1950-01-01 to 1978-03-22; source msha-controller-operator-history
- **operator_operates_mine:** Hub Materials Inc → Turner Dry Sand Plant; 1978-03-23 to 1984-07-10; source msha-controller-operator-history
- **controller_controls_mine:** Wolfe R E → Turner Dry Sand Plant; 1978-03-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wolfe R E → Hub Materials Inc; 1978-03-23 to 1984-07-10; source msha-controller-operator-history
- **operator_operates_mine:** Kaw Valley Sand and Gravel, Inc. → Turner Dry Sand Plant; 1984-07-11 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ben G  Kates → Turner Dry Sand Plant; 1984-07-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ben G  Kates → Kaw Valley Sand and Gravel, Inc.; 1984-07-11 to current/open; source msha-controller-operator-history