# Relationship history for MSHA mine 1517202

Current hierarchy: **George E  Barker → New Horizons Coal Inc → Dulcimer #7**

- 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:** Great Western Resources Inc → Dulcimer #7; 1987-02-04 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** New Horizons Coal Inc → Dulcimer #7; 1992-02-01 to 1995-08-14; source msha-controller-operator-history
- **controller_controls_operator:** Great Western Resources Inc → New Horizons Coal Inc; 1992-02-01 to 1995-08-14; source msha-controller-operator-history
- **operator_operates_mine:** New Horizons Coal Inc → Dulcimer #7; 1995-08-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** George E  Barker → Dulcimer #7; 1995-08-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** George E  Barker → New Horizons Coal Inc; 1995-08-15 to current/open; source msha-controller-operator-history