# Relationship history for MSHA mine 5001261

Current hierarchy: **Arctic Slope Regional Corp → ASRC Energy Services Alaska, Inc. → Power Screen Chieftan 1400 Kuparuk**

- 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:** Alaska Oilfield Service → Power Screen Chieftan 1400 Kuparuk; 1978-10-03 to 2011-06-24; source msha-controller-operator-history
- **controller_controls_mine:** Alaska Oilfield Service → Power Screen Chieftan 1400 Kuparuk; 1978-10-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alaska Oilfield Service → Alaska Oilfield Service; 1978-10-03 to 2011-06-24; source msha-controller-operator-history
- **operator_operates_mine:** ASRC Energy Services Alaska, Inc. → Power Screen Chieftan 1400 Kuparuk; 2011-06-25 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Arctic Slope Regional Corp → Power Screen Chieftan 1400 Kuparuk; 2011-06-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Arctic Slope Regional Corp → ASRC Energy Services Alaska, Inc.; 2011-06-25 to current/open; source msha-controller-operator-history