# Relationship history for MSHA mine 3401832

Current hierarchy: **Summit Materials LLC → Smith Crushed Stone → WILLIS PLANT**

- 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:** Eddie G  Smith et al → WILLIS PLANT; 1994-03-01 to 2011-01-31; source msha-controller-operator-history
- **operator_operates_mine:** Smith Crushed Stone → WILLIS PLANT; 1999-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Eddie G  Smith et al → Smith Crushed Stone; 1999-08-01 to 2011-01-31; source msha-controller-operator-history
- **controller_controls_operator:** Mark  Buster et al → Smith Crushed Stone; 1999-08-01 to 2011-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Summit Materials LLC → WILLIS PLANT; 2011-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Summit Materials LLC → Smith Crushed Stone; 2011-02-01 to current/open; source msha-controller-operator-history