# Relationship history for MSHA mine 2900194

Current hierarchy: **Cemex S A → Rinker Materials Western Inc. → Rinker Materials Des Moines Quarry**

- 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

- **operator_operates_mine:** Twin Mountain Rock Company → Rinker Materials Des Moines Quarry; 1950-01-01 to 2002-09-25; source msha-controller-operator-history
- **controller_controls_mine:** Peter Kiewit Sons' Inc → Rinker Materials Des Moines Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Peter Kiewit Sons' Inc → Twin Mountain Rock Company; 1950-01-01 to 2002-09-25; source msha-controller-operator-history
- **operator_operates_mine:** Rinker Materials Western Inc. → Rinker Materials Des Moines Quarry; 2002-09-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** CSR Ltd → Rinker Materials Des Moines Quarry; 2002-09-26 to 2003-03-31; source msha-controller-operator-history
- **controller_controls_operator:** CSR Ltd → Rinker Materials Western Inc.; 2002-09-26 to 2003-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Rinker Group Ltd → Rinker Materials Des Moines Quarry; 2003-04-01 to 2007-07-09; source msha-controller-operator-history
- **controller_controls_operator:** Rinker Group Ltd → Rinker Materials Western Inc.; 2003-04-01 to 2007-07-09; source msha-controller-operator-history
- **controller_controls_mine:** Cemex S A → Rinker Materials Des Moines Quarry; 2007-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cemex S A → Rinker Materials Western Inc.; 2007-07-10 to current/open; source msha-controller-operator-history