# Relationship history for MSHA mine 1600001

Current hierarchy: **George  Douglass Jr → Pontchartrain Dredging Corp → Dredge Lacombe**

- 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

- **controller_controls_mine:** George  Douglass Jr → Dredge Lacombe; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Harvey Industries Inc → Dredge Lacombe; 1950-01-01 to 1979-12-21; source msha-controller-operator-history
- **controller_controls_mine:** Loumiet Enterprises Inc → Dredge Lacombe; 1950-01-01 to 1979-12-21; source msha-controller-operator-history
- **controller_controls_operator:** Loumiet Enterprises Inc → Harvey Industries Inc; 1950-01-01 to 1979-12-21; source msha-controller-operator-history
- **operator_operates_mine:** Pontchartrain Dredging Corp → Dredge Lacombe; 1979-12-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** George  Douglass Jr → Pontchartrain Dredging Corp; 1979-12-22 to current/open; source msha-controller-operator-history