# Relationship history for MSHA mine 4002166

Current hierarchy: **Howard Ray → Smokey Creek Coal Company → Smokey Creek Mine**

- 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:** Massengale Coal Company → Smokey Creek Mine; 1976-12-01 to 1977-02-17; source msha-controller-operator-history
- **controller_controls_mine:** Massengale Kenneth → Smokey Creek Mine; 1976-12-01 to 1977-02-17; source msha-controller-operator-history
- **controller_controls_operator:** Massengale Kenneth → Massengale Coal Company; 1976-12-01 to 1977-02-17; source msha-controller-operator-history
- **operator_operates_mine:** B & L Coal Company → Smokey Creek Mine; 1977-02-18 to 1980-02-29; source msha-controller-operator-history
- **controller_controls_mine:** Buress Elmer L & Clarence Lowe → Smokey Creek Mine; 1977-02-18 to 1980-02-29; source msha-controller-operator-history
- **controller_controls_operator:** Buress Elmer L & Clarence Lowe → B & L Coal Company; 1977-02-18 to 1980-02-29; source msha-controller-operator-history
- **operator_operates_mine:** Smokey Creek Coal Company → Smokey Creek Mine; 1980-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Howard Ray → Smokey Creek Mine; 1980-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Howard Ray → Smokey Creek Coal Company; 1980-03-01 to current/open; source msha-controller-operator-history