# Relationship history for MSHA mine 1510660

Current hierarchy: **Benjamin R.  Bennett → Rb Coal Company Inc → Kellioka No 1 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

- **controller_controls_mine:** Swartwood T Marshall → Kellioka No 1 Mine; 1975-06-02 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Coal Fuels Inc → Kellioka No 1 Mine; 1977-07-01 to 1979-11-28; source msha-controller-operator-history
- **controller_controls_operator:** Swartwood T Marshall → Coal Fuels Inc; 1977-07-01 to 1979-11-28; source msha-controller-operator-history
- **operator_operates_mine:** Rb Coal Company Inc → Kellioka No 1 Mine; 1979-11-29 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Benjamin R.  Bennett → Kellioka No 1 Mine; 1979-11-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Benjamin R.  Bennett → Rb Coal Company Inc; 1979-11-29 to current/open; source msha-controller-operator-history