# Relationship history for MSHA mine 1519071

Current hierarchy: **Headwaters Inc → Covol Fuels No. 2, LLC → Rock Crusher Plant Site**

- 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:** Phoenix Coal Processing Company LLC → Rock Crusher Plant Site; 2006-12-22 to 2007-12-05; source msha-controller-operator-history
- **controller_controls_mine:** Phoenix Coal Corporation → Rock Crusher Plant Site; 2006-12-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Phoenix Coal Corporation → Phoenix Coal Processing Company LLC; 2006-12-22 to 2007-12-05; source msha-controller-operator-history
- **operator_operates_mine:** Covol Fuels No. 2, LLC → Rock Crusher Plant Site; 2007-12-06 to 2013-01-15; source msha-controller-operator-history
- **controller_controls_mine:** Headwaters Inc → Rock Crusher Plant Site; 2007-12-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Headwaters Inc → Covol Fuels No. 2, LLC; 2007-12-06 to 2013-01-15; source msha-controller-operator-history
- **operator_operates_mine:** BRC Rockcrusher LLC → Rock Crusher Plant Site; 2013-01-16 to 2015-06-21; source msha-controller-operator-history
- **controller_controls_mine:** Steve  Rickmeier et al → Rock Crusher Plant Site; 2013-01-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Steve  Rickmeier et al → BRC Rockcrusher LLC; 2013-01-16 to 2015-06-21; source msha-controller-operator-history
- **operator_operates_mine:** Covol Fuels No. 2, LLC → Rock Crusher Plant Site; 2015-06-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Headwaters Inc → Covol Fuels No. 2, LLC; 2015-06-22 to current/open; source msha-controller-operator-history