# Relationship history for MSHA mine 4002546

Current hierarchy: **B Wayne  Workman → West Tennessee Gravel Co. → West Tennessee Gravel Co.**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Flowers B L → West Tennessee Gravel Co.; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** B L Flowers Gravel Company → West Tennessee Gravel Co.; 1979-01-01 to 1980-01-31; source msha-controller-operator-history
- **controller_controls_operator:** Flowers B L → B L Flowers Gravel Company; 1979-01-01 to 1980-01-31; source msha-controller-operator-history
- **operator_operates_mine:** West Tennessee Gravel Co. → West Tennessee Gravel Co.; 1980-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** B Wayne  Workman → West Tennessee Gravel Co.; 1980-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** B Wayne  Workman → West Tennessee Gravel Co.; 1980-02-01 to current/open; source msha-controller-operator-history