# Relationship history for MSHA mine 1513002

Current hierarchy: **Hall Ronald → B & R Coal Company Inc → No 1**

- 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

- **operator_operates_mine:** Sandy Lynn Coal Company Inc → No 1; 1981-07-01 to 1985-06-16; source msha-controller-operator-history
- **controller_controls_mine:** Webb Hobert Sr → No 1; 1981-07-01 to 1985-06-16; source msha-controller-operator-history
- **controller_controls_operator:** Webb Hobert Sr → Sandy Lynn Coal Company Inc; 1981-07-01 to 1985-06-16; source msha-controller-operator-history
- **operator_operates_mine:** B & R Coal Company Inc → No 1; 1985-06-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hall Ronald → No 1; 1985-06-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hall Ronald → B & R Coal Company Inc; 1985-06-17 to current/open; source msha-controller-operator-history