# Relationship history for MSHA mine 2601920

Current hierarchy: **Sterling Infrastructure Inc; Richard H  Buenting → Road and Highway Builders, LLC → Portable Crusher #1003**

- 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

- **controller_controls_mine:** Garth  Frehner → Portable Crusher #1003; 1983-08-01 to 2004-05-09; source msha-controller-operator-history
- **operator_operates_mine:** Frehner Construction Co Inc → Portable Crusher #1003; 1985-05-01 to 2012-04-26; source msha-controller-operator-history
- **controller_controls_operator:** Garth  Frehner → Frehner Construction Co Inc; 1985-05-01 to 2004-05-09; source msha-controller-operator-history
- **controller_controls_mine:** Aggregate Industries PLC → Portable Crusher #1003; 2004-05-10 to 2009-04-29; source msha-controller-operator-history
- **controller_controls_operator:** Aggregate Industries PLC → Frehner Construction Co Inc; 2004-05-10 to 2009-04-29; source msha-controller-operator-history
- **controller_controls_mine:** Holcim Ltd → Portable Crusher #1003; 2009-04-30 to 2015-07-09; source msha-controller-operator-history
- **controller_controls_operator:** Holcim Ltd → Frehner Construction Co Inc; 2009-04-30 to 2012-04-26; source msha-controller-operator-history
- **controller_controls_mine:** Sterling Infrastructure Inc et al → Portable Crusher #1003; 2009-11-20 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Road and Highway Builders, LLC → Portable Crusher #1003; 2012-04-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sterling Infrastructure Inc et al → Road and Highway Builders, LLC; 2012-04-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard H  Buenting et al → Road and Highway Builders, LLC; 2012-04-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Holcim Ltd → Portable Crusher #1003; 2015-07-10 to 2025-06-22; source msha-controller-operator-history
- **controller_controls_operator:** Holcim Ltd → Frehner Construction Co Inc; 2015-07-10 to 2012-04-26; source msha-controller-operator-history
- **controller_controls_mine:** Amrize Ltd → Portable Crusher #1003; 2025-06-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Amrize Ltd → Frehner Construction Co Inc; 2025-06-23 to 2012-04-26; source msha-controller-operator-history