# Relationship history for MSHA mine 4002486

Current hierarchy: **Wolcott John F → Wolco Energy Inc → Wolco Energy Prep 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

- **operator_operates_mine:** Black Jack Tipple Inc → Wolco Energy Prep Plant; 1978-12-01 to 1981-10-31; source msha-controller-operator-history
- **controller_controls_mine:** Reynolds H M → Wolco Energy Prep Plant; 1978-12-01 to 1981-10-31; source msha-controller-operator-history
- **controller_controls_operator:** Reynolds H M → Black Jack Tipple Inc; 1978-12-01 to 1981-10-31; source msha-controller-operator-history
- **operator_operates_mine:** Lazy Seven Coal Sales Inc → Wolco Energy Prep Plant; 1981-11-01 to 1987-12-27; source msha-controller-operator-history
- **controller_controls_mine:** Mehler Frank T → Wolco Energy Prep Plant; 1981-11-01 to 1987-12-27; source msha-controller-operator-history
- **controller_controls_operator:** Mehler Frank T → Lazy Seven Coal Sales Inc; 1981-11-01 to 1987-12-27; source msha-controller-operator-history
- **operator_operates_mine:** Wolco Energy Inc → Wolco Energy Prep Plant; 1987-12-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Wolcott John F → Wolco Energy Prep Plant; 1987-12-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wolcott John F → Wolco Energy Inc; 1987-12-28 to current/open; source msha-controller-operator-history