# Relationship history for MSHA mine 1509325

Current hierarchy: **Stanford Energy → B & H Elkhorn Coal Company → No 1 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Ranier Harry Hale → No 1 Surface; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** B & H Elkhorn Coal Company → No 1 Surface; 1975-11-06 to 1977-12-11; source msha-controller-operator-history
- **controller_controls_operator:** Ranier Harry Hale → B & H Elkhorn Coal Company; 1975-11-06 to 1977-12-11; source msha-controller-operator-history
- **operator_operates_mine:** B & H Elkhorn Coal Company → No 1 Surface; 1977-12-12 to 1983-06-30; source msha-controller-operator-history
- **controller_controls_mine:** Zapata Corp → No 1 Surface; 1977-12-12 to 1983-06-30; source msha-controller-operator-history
- **controller_controls_operator:** Zapata Corp → B & H Elkhorn Coal Company; 1977-12-12 to 1983-06-30; source msha-controller-operator-history
- **operator_operates_mine:** B & H Elkhorn Coal Company → No 1 Surface; 1983-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Stanford Energy → No 1 Surface; 1983-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Stanford Energy → B & H Elkhorn Coal Company; 1983-07-01 to current/open; source msha-controller-operator-history