# Relationship history for MSHA mine 1510568

Current hierarchy: **Newman Edmond → N & I Coal Company Inc → No 1 Mine**

- 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:** Couch Denver → No 1 Mine; 1976-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Denver Couch Coal Company → No 1 Mine; 1977-07-01 to 1977-09-28; source msha-controller-operator-history
- **controller_controls_operator:** Couch Denver → Denver Couch Coal Company; 1977-07-01 to 1977-09-28; source msha-controller-operator-history
- **controller_controls_mine:** Newman Edmond → No 1 Mine; 1977-09-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** N & I Coal Company Inc → No 1 Mine; 1977-09-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Newman Edmond → N & I Coal Company Inc; 1977-09-29 to current/open; source msha-controller-operator-history