# Relationship history for MSHA mine 4609237

Current hierarchy: **Alpha Metallurgical Resources Inc → Mammoth Coal Co. → Alloy Powellton**

- 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:** Massey Energy Company → Alloy Powellton; 1996-02-05 to 2011-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Energy Coal Resources Inc → Alloy Powellton; 2006-08-23 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Appalachian Premium Fuels LLC → Alloy Powellton; 2007-09-25 to 2009-09-30; source msha-controller-operator-history
- **controller_controls_operator:** Energy Coal Resources Inc → Appalachian Premium Fuels LLC; 2007-09-25 to 2009-09-30; source msha-controller-operator-history
- **operator_operates_mine:** Mammoth Coal Co. → Alloy Powellton; 2009-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Massey Energy Company → Mammoth Coal Co.; 2009-10-01 to 2011-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Alpha Natural Resources, Inc. → Alloy Powellton; 2011-06-01 to 2016-07-25; source msha-controller-operator-history
- **controller_controls_operator:** Alpha Natural Resources, Inc. → Mammoth Coal Co.; 2011-06-01 to 2016-07-25; source msha-controller-operator-history
- **controller_controls_mine:** Alpha Natural Resources Holdings, Inc → Alloy Powellton; 2016-07-26 to 2018-11-08; source msha-controller-operator-history
- **controller_controls_operator:** Alpha Natural Resources Holdings, Inc → Mammoth Coal Co.; 2016-07-26 to 2018-11-08; source msha-controller-operator-history
- **controller_controls_mine:** Alpha Metallurgical Resources Inc → Alloy Powellton; 2018-11-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alpha Metallurgical Resources Inc → Mammoth Coal Co.; 2018-11-09 to current/open; source msha-controller-operator-history