# Relationship history for MSHA mine 4503321

Current hierarchy: **Donna L  Settlemier → Cowlitz Valley Sand & Gravel Inc → ALUMINA CLAY PIT**

- 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:** Donald  Taylor → ALUMINA CLAY PIT; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Donna L  Settlemier → ALUMINA CLAY PIT; 1993-03-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Olson & Taylor Inc → ALUMINA CLAY PIT; 1994-06-01 to 1998-06-30; source msha-controller-operator-history
- **controller_controls_operator:** Donald  Taylor → Olson & Taylor Inc; 1994-06-01 to 1998-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Cowlitz Valley Sand & Gravel Inc → ALUMINA CLAY PIT; 1998-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Donna L  Settlemier → Cowlitz Valley Sand & Gravel Inc; 1998-07-01 to current/open; source msha-controller-operator-history