# Relationship history for MSHA mine 2600457

Current hierarchy: **CSR Ltd → Wmk Transit Mix → Gibson Road Pit & Mill**

- 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:** Wmk Transit Mix → Gibson Road Pit & Mill; 1950-01-01 to 1980-02-29; source msha-controller-operator-history
- **controller_controls_mine:** Taggart Construction Company → Gibson Road Pit & Mill; 1950-01-01 to 1980-02-29; source msha-controller-operator-history
- **controller_controls_operator:** Taggart Construction Company → Wmk Transit Mix; 1950-01-01 to 1980-02-29; source msha-controller-operator-history
- **operator_operates_mine:** Arc Materials Corp D/B/A Wmk Transit Mix → Gibson Road Pit & Mill; 1980-03-01 to 1989-08-09; source msha-controller-operator-history
- **controller_controls_mine:** Consolidated Gold Fields Limited → Gibson Road Pit & Mill; 1980-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Consolidated Gold Fields Limited → Arc Materials Corp D/B/A Wmk Transit Mix; 1980-03-01 to 1989-08-09; source msha-controller-operator-history
- **operator_operates_mine:** Wmk Transit Mix → Gibson Road Pit & Mill; 1989-08-10 to 1990-02-01; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Gibson Road Pit & Mill; 1989-08-10 to 1990-02-01; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Wmk Transit Mix; 1989-08-10 to 1990-02-01; source msha-controller-operator-history
- **operator_operates_mine:** Wmk Transit Mix → Gibson Road Pit & Mill; 1990-02-02 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** CSR Ltd → Gibson Road Pit & Mill; 1990-02-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CSR Ltd → Wmk Transit Mix; 1990-02-02 to current/open; source msha-controller-operator-history