# Relationship history for MSHA mine 1511121

Current hierarchy: **Michael  Blubaugh → Kingdom Coal, LLC → Roxana Prep Plant**

- 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

- **controller_controls_mine:** Howell Corporation → Roxana Prep Plant; 1977-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Lake Coal Company Inc → Roxana Prep Plant; 1978-03-01 to 1989-04-03; source msha-controller-operator-history
- **controller_controls_operator:** Howell Corporation → Lake Coal Company Inc; 1978-03-01 to 1989-04-03; source msha-controller-operator-history
- **operator_operates_mine:** Coastal Coal Company, LLC → Roxana Prep Plant; 1989-04-04 to 2003-01-31; source msha-controller-operator-history
- **controller_controls_mine:** El Paso Energy Corp → Roxana Prep Plant; 1989-04-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** El Paso Energy Corp → Coastal Coal Company, LLC; 1989-04-04 to 2003-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Amfire LLC → Roxana Prep Plant; 2003-01-31 to 2003-01-31; source msha-controller-operator-history
- **operator_operates_mine:** Enterprise Mining Company LLC → Roxana Prep Plant; 2003-02-01 to 2016-10-12; source msha-controller-operator-history
- **controller_controls_mine:** Alpha Natural Resources, Inc. → Roxana Prep Plant; 2003-02-01 to 2016-07-25; source msha-controller-operator-history
- **controller_controls_operator:** Alpha Natural Resources, Inc. → Enterprise Mining Company LLC; 2003-02-01 to 2016-07-25; source msha-controller-operator-history
- **controller_controls_operator:** Amfire LLC → Enterprise Mining Company LLC; 2003-02-01 to 2003-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Alpha Natural Resources Holdings, Inc → Roxana Prep Plant; 2016-07-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alpha Natural Resources Holdings, Inc → Enterprise Mining Company LLC; 2016-07-26 to 2016-10-12; source msha-controller-operator-history
- **operator_operates_mine:** Kingdom Coal, LLC → Roxana Prep Plant; 2016-10-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Douglas  Warriner → Roxana Prep Plant; 2016-10-13 to 2018-08-15; source msha-controller-operator-history
- **controller_controls_operator:** Douglas  Warriner → Kingdom Coal, LLC; 2016-10-13 to 2018-08-15; source msha-controller-operator-history
- **controller_controls_mine:** Douglas S  Warriner et al → Roxana Prep Plant; 2018-08-16 to 2020-07-11; source msha-controller-operator-history
- **controller_controls_operator:** Douglas S  Warriner et al → Kingdom Coal, LLC; 2018-08-16 to 2020-07-11; source msha-controller-operator-history
- **controller_controls_operator:** Michael A  Blubaugh et al → Kingdom Coal, LLC; 2018-08-16 to 2020-07-11; source msha-controller-operator-history
- **controller_controls_mine:** Michael  Blubaugh → Roxana Prep Plant; 2020-07-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael  Blubaugh → Kingdom Coal, LLC; 2020-07-12 to current/open; source msha-controller-operator-history