# Relationship history for MSHA mine 1301427

Current hierarchy: **MDU Resources Group Inc → Roverud Construction Inc → Eckerman Sand & 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** J F Pavlovec Rock Company Inc → Eckerman Sand & Gravel; 1950-01-01 to 1981-08-09; source msha-controller-operator-history
- **controller_controls_mine:** Pavlovec Joseph F → Eckerman Sand & Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Pavlovec Joseph F → J F Pavlovec Rock Company Inc; 1950-01-01 to 1981-08-09; source msha-controller-operator-history
- **controller_controls_mine:** Jeff C Roverud et al → Eckerman Sand & Gravel; 1950-01-01 to 2004-02-04; source msha-controller-operator-history
- **operator_operates_mine:** Roverud Construction Inc → Eckerman Sand & Gravel; 1981-08-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jeff C Roverud et al → Roverud Construction Inc; 1981-08-10 to 2004-02-04; source msha-controller-operator-history
- **controller_controls_operator:** Curtis G Roverud et al → Roverud Construction Inc; 1981-08-10 to 2004-02-04; source msha-controller-operator-history
- **controller_controls_mine:** MDU Resources Group Inc → Eckerman Sand & Gravel; 2004-02-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** MDU Resources Group Inc → Roverud Construction Inc; 2004-02-05 to current/open; source msha-controller-operator-history
