# Relationship history for MSHA mine 2500979

Current hierarchy: **Michelle R Wolinski EtAl; Derek A Wolinski EtAl → Tri-County Sand & Gravel Inc → Elba 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:** Kyle R  Wolinski → Elba Pit; 1980-02-01 to 2019-12-24; source msha-controller-operator-history
- **operator_operates_mine:** Tri-County Sand & Gravel Inc → Elba Pit; 1980-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kyle R  Wolinski → Tri-County Sand & Gravel Inc; 1980-06-01 to 2019-12-24; source msha-controller-operator-history
- **controller_controls_mine:** Michelle R Wolinski EtAl → Elba Pit; 2019-12-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michelle R Wolinski EtAl → Tri-County Sand & Gravel Inc; 2019-12-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Derek A Wolinski EtAl → Tri-County Sand & Gravel Inc; 2019-12-25 to current/open; source msha-controller-operator-history