# Relationship history for MSHA mine 1513439

Current hierarchy: **James River Coal Company → Mc Coy Elkhorn Coal Corp → No 8a 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

- **operator_operates_mine:** Mc Coy Elkhorn Coal Corp → No 8a Mine; 1982-04-01 to 1988-09-27; source msha-controller-operator-history
- **controller_controls_mine:** Williams Companies Inc → No 8a Mine; 1982-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Williams Companies Inc → Mc Coy Elkhorn Coal Corp; 1982-04-01 to 1988-09-27; source msha-controller-operator-history
- **operator_operates_mine:** Mc Coy Elkhorn Coal Corp → No 8a Mine; 1988-09-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** James River Coal Company → No 8a Mine; 1988-09-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James River Coal Company → Mc Coy Elkhorn Coal Corp; 1988-09-28 to current/open; source msha-controller-operator-history