# Relationship history for MSHA mine 4501165

Current hierarchy: **Charles  Gallagher → Aimcor Olivine → Twin Sisters 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

- **controller_controls_mine:** IMC Global Inc → Twin Sisters Quarry; 1950-01-01 to 1986-11-02; source msha-controller-operator-history
- **operator_operates_mine:** Olson & Taylor Trucking Inc → Twin Sisters Quarry; 1950-01-01 to 1982-06-23; source msha-controller-operator-history
- **controller_controls_mine:** Donald  Taylor → Twin Sisters Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Donald  Taylor → Olson & Taylor Trucking Inc; 1950-01-01 to 1982-06-23; source msha-controller-operator-history
- **operator_operates_mine:** Imc Olivine → Twin Sisters Quarry; 1982-06-24 to 1986-11-02; source msha-controller-operator-history
- **controller_controls_operator:** IMC Global Inc → Imc Olivine; 1982-06-24 to 1986-11-02; source msha-controller-operator-history
- **controller_controls_mine:** Charles  Gallagher et al → Twin Sisters Quarry; 1986-11-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Aimcor Olivine → Twin Sisters Quarry; 1986-11-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Charles  Gallagher et al → Aimcor Olivine; 1986-11-03 to current/open; source msha-controller-operator-history