# Relationship history for MSHA mine 1001954

Current hierarchy: **Washington Group International Inc → Morrison Knudsen Corp An Ohio Corp → PUG MILL 3-203**

- 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:** Washington Group International Inc → PUG MILL 3-203; 1998-12-22 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Morrison Knudsen Corp An Ohio Corp → PUG MILL 3-203; 1999-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Washington Group International Inc → Morrison Knudsen Corp An Ohio Corp; 1999-05-01 to current/open; source msha-controller-operator-history