# Relationship history for MSHA mine 1510189

Current hierarchy: **Costain Group PLC → Chapperal Coal Corp → No 2-A Mine (D)**

- 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:** Nick A  Cooley et al → No 2-A Mine (D); 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Chapperal Coal Corp → No 2-A Mine (D); 1977-01-01 to 1978-10-04; source msha-controller-operator-history
- **controller_controls_operator:** Nick A  Cooley et al → Chapperal Coal Corp; 1977-01-01 to 1978-10-04; source msha-controller-operator-history
- **operator_operates_mine:** Chapperal Coal Corp → No 2-A Mine (D); 1978-10-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Costain Group PLC → No 2-A Mine (D); 1978-10-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Costain Group PLC → Chapperal Coal Corp; 1978-10-05 to current/open; source msha-controller-operator-history