# Relationship history for MSHA mine 4105331

Current hierarchy: **USS Holdings Inc → U.S. Silica Energy Company → Crane County 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** USS Holdings Inc → Crane County Plant; 1996-03-09 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** U.S. Silica → Crane County Plant; 2018-03-01 to 2025-03-27; source msha-controller-operator-history
- **controller_controls_operator:** USS Holdings Inc → U.S. Silica; 2018-03-01 to 2025-03-27; source msha-controller-operator-history
- **operator_operates_mine:** U.S. Silica Energy Company → Crane County Plant; 2025-03-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** USS Holdings Inc → Crane County Plant; 2025-03-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** USS Holdings Inc → U.S. Silica Energy Company; 2025-03-28 to current/open; source msha-controller-operator-history