# Relationship history for MSHA mine 1517931

Current hierarchy: **Henry  Chaney Jr → Cheyenne Elkhorn Coal Company Inc → #6**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Henry  Chaney Jr → #6; 1976-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** (Donald) Todd  Kiscaden et al → #6; 1997-01-01 to 1997-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Marine Coal Corp → #6; 1997-04-01 to 1997-06-30; source msha-controller-operator-history
- **controller_controls_operator:** (Donald) Todd  Kiscaden et al → Marine Coal Corp; 1997-04-01 to 1997-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Branham & Baker Underground Corp → #6; 1997-07-01 to 1998-06-10; source msha-controller-operator-history
- **controller_controls_mine:** Donn A  Chickering → #6; 1997-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Donn A  Chickering → Branham & Baker Underground Corp; 1997-07-01 to 1998-06-10; source msha-controller-operator-history
- **operator_operates_mine:** Cheyenne Elkhorn Coal Company Inc → #6; 1998-06-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Henry  Chaney Jr → Cheyenne Elkhorn Coal Company Inc; 1998-06-11 to current/open; source msha-controller-operator-history