# Relationship history for MSHA mine 1511334

Current hierarchy: **Frontier Companies Of Alaska → 10-Creek Mining Company → Elk Ridge No 2 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** 10-Creek Mining Company → Elk Ridge No 2 Surface; 1978-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Frontier Companies Of Alaska → Elk Ridge No 2 Surface; 1978-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Frontier Companies Of Alaska → 10-Creek Mining Company; 1978-05-01 to current/open; source msha-controller-operator-history