# Relationship history for MSHA mine 4702564

Current hierarchy: **Dennis L  Nordstrand → Yellow River Supply Corp → Crotteau 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Milton D  Ostermann → Crotteau Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Ostermann Sand & Gravel Inc → Crotteau Pit; 1979-01-01 to 1984-02-16; source msha-controller-operator-history
- **controller_controls_operator:** Milton D  Ostermann → Ostermann Sand & Gravel Inc; 1979-01-01 to 1984-02-16; source msha-controller-operator-history
- **operator_operates_mine:** Yellow River Supply Corp → Crotteau Pit; 1984-02-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Dennis L  Nordstrand → Crotteau Pit; 1984-02-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dennis L  Nordstrand → Yellow River Supply Corp; 1984-02-17 to current/open; source msha-controller-operator-history