# Relationship history for MSHA mine 2100579

Current hierarchy: **CRH PLC → Southern MN Construction → Medford Wash 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:** Concrete Materials Inc → Medford Wash Plant; 1950-01-01 to 1985-04-08; source msha-controller-operator-history
- **controller_controls_mine:** Don  Hammel → Medford Wash Plant; 1950-01-01 to 1987-02-28; source msha-controller-operator-history
- **controller_controls_operator:** Don  Hammel → Concrete Materials Inc; 1950-01-01 to 1985-04-08; source msha-controller-operator-history
- **operator_operates_mine:** Crane Creek Asphalt Inc → Medford Wash Plant; 1985-04-09 to 1989-03-07; source msha-controller-operator-history
- **controller_controls_mine:** Richard C  Lundin  et al → Medford Wash Plant; 1985-04-09 to 1989-03-07; source msha-controller-operator-history
- **controller_controls_operator:** Richard C  Lundin  et al → Crane Creek Asphalt Inc; 1985-04-09 to 1989-03-07; source msha-controller-operator-history
- **controller_controls_mine:** Larry V  Nurre → Medford Wash Plant; 1988-07-01 to 2006-03-01; source msha-controller-operator-history
- **operator_operates_mine:** Owatonna Construction Co. → Medford Wash Plant; 1989-03-08 to 2006-03-22; source msha-controller-operator-history
- **controller_controls_mine:** Gerald A Redman et al → Medford Wash Plant; 1989-03-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gerald A Redman et al → Owatonna Construction Co.; 1989-03-08 to 2006-03-22; source msha-controller-operator-history
- **controller_controls_operator:** Donald F Redman et al → Owatonna Construction Co.; 1989-03-08 to 2006-03-22; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Medford Wash Plant; 2006-03-02 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Southern Minnesota Construction Company, Inc → Medford Wash Plant; 2006-03-23 to 2008-12-27; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Southern Minnesota Construction Company, Inc; 2006-03-23 to 2008-12-27; source msha-controller-operator-history
- **controller_controls_operator:** Larry V  Nurre → Southern Minnesota Construction Company, Inc; 2006-03-23 to 2006-03-01; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Medford Wash Plant; 2008-01-03 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Southern MN Construction → Medford Wash Plant; 2008-12-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Southern MN Construction; 2008-12-28 to current/open; source msha-controller-operator-history