# Relationship history for MSHA mine 1515470

Current hierarchy: **Davidson Oscoe → Colo Mining Company Inc → No 1 Surface**

- 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

- **operator_operates_mine:** Colo Mining Inc → No 1 Surface; 1985-12-01 to 1986-05-04; source msha-controller-operator-history
- **controller_controls_mine:** Smith Tony Et Al → No 1 Surface; 1985-12-01 to 1986-05-04; source msha-controller-operator-history
- **controller_controls_operator:** Smith Tony Et Al → Colo Mining Inc; 1985-12-01 to 1986-05-04; source msha-controller-operator-history
- **operator_operates_mine:** Colo Mining Company Inc → No 1 Surface; 1986-05-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Davidson Oscoe → No 1 Surface; 1986-05-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Davidson Oscoe → Colo Mining Company Inc; 1986-05-05 to current/open; source msha-controller-operator-history