# Relationship history for MSHA mine 0504081

Current hierarchy: **Sedgwick County-Co → Sedgwick County Road & Bridge Maint & Const → SEDGWICK COUNTY PORTABLE PLANT 1**

- 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:** Sedgwick County Road & Bridge Maint & Const → SEDGWICK COUNTY PORTABLE PLANT 1; 1985-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Sedgwick County-Co → SEDGWICK COUNTY PORTABLE PLANT 1; 1985-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sedgwick County-Co → Sedgwick County Road & Bridge Maint & Const; 1985-08-01 to current/open; source msha-controller-operator-history