# Relationship history for MSHA mine 0504598

Current hierarchy: **Teller County-Co → Teller County Road & Bridge Department → Teller County Screen #2**

- 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:** Teller County-Co → Teller County Screen #2; 1996-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Teller County Road & Bridge Department → Teller County Screen #2; 1997-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Teller County-Co → Teller County Road & Bridge Department; 1997-06-01 to current/open; source msha-controller-operator-history