# Relationship history for MSHA mine 1508200

Current hierarchy: **Michael  Puskarich → Bluegrass Mining → Bluegrass 006 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:** Zane Alexander Engineering Company Inc → Bluegrass 006 Surface; 1975-04-01 to 1977-06-06; source msha-controller-operator-history
- **controller_controls_mine:** Alexander Zane → Bluegrass 006 Surface; 1975-04-01 to 1977-06-06; source msha-controller-operator-history
- **controller_controls_operator:** Alexander Zane → Zane Alexander Engineering Company Inc; 1975-04-01 to 1977-06-06; source msha-controller-operator-history
- **operator_operates_mine:** Huscoal Inc → Bluegrass 006 Surface; 1977-06-07 to 1980-10-23; source msha-controller-operator-history
- **controller_controls_mine:** Hughes Group Inc → Bluegrass 006 Surface; 1977-06-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hughes Group Inc → Huscoal Inc; 1977-06-07 to 1980-10-23; source msha-controller-operator-history
- **controller_controls_mine:** Michael  Puskarich  et al → Bluegrass 006 Surface; 1977-09-16 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bluegrass Mining → Bluegrass 006 Surface; 1980-10-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael  Puskarich  et al → Bluegrass Mining; 1980-10-24 to current/open; source msha-controller-operator-history