# Relationship history for MSHA mine 3606276

Current hierarchy: **Schlabach Alvin--Glen Hoagland & Jerry Trout → Summit Coal Company → Summit Coal Company**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Summit Coal & Contracting Inc → Summit Coal Company; 1976-12-01 to 1978-04-12; source msha-controller-operator-history
- **controller_controls_mine:** Schlabach Alvin--Glen Hoagland & Jerry Trout → Summit Coal Company; 1976-12-01 to 1978-04-12; source msha-controller-operator-history
- **controller_controls_operator:** Schlabach Alvin--Glen Hoagland & Jerry Trout → Summit Coal & Contracting Inc; 1976-12-01 to 1978-04-12; source msha-controller-operator-history
- **operator_operates_mine:** Summit Mining Corp → Summit Coal Company; 1978-04-13 to 1979-02-12; source msha-controller-operator-history
- **controller_controls_mine:** Blum Bentley J → Summit Coal Company; 1978-04-13 to 1979-02-12; source msha-controller-operator-history
- **controller_controls_operator:** Blum Bentley J → Summit Mining Corp; 1978-04-13 to 1979-02-12; source msha-controller-operator-history
- **operator_operates_mine:** Summit Mining Corp → Summit Coal Company; 1979-02-13 to 1979-09-09; source msha-controller-operator-history
- **controller_controls_mine:** Valeri Carl C → Summit Coal Company; 1979-02-13 to 1979-09-09; source msha-controller-operator-history
- **controller_controls_operator:** Valeri Carl C → Summit Mining Corp; 1979-02-13 to 1979-09-09; source msha-controller-operator-history
- **operator_operates_mine:** Summit Coal Company → Summit Coal Company; 1979-09-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Schlabach Alvin--Glen Hoagland & Jerry Trout → Summit Coal Company; 1979-09-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Schlabach Alvin--Glen Hoagland & Jerry Trout → Summit Coal Company; 1979-09-10 to current/open; source msha-controller-operator-history