# Relationship history for MSHA mine 3607311

Current hierarchy: **Stephen  Perchinski → Brown Coal Company → No 1 Slope**

- 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:** Big Diamond Coal Company → No 1 Slope; 1982-05-01 to 1983-02-28; source msha-controller-operator-history
- **controller_controls_mine:** Poletti Peter J & Larry M Et Al → No 1 Slope; 1982-05-01 to 1983-02-28; source msha-controller-operator-history
- **controller_controls_operator:** Poletti Peter J & Larry M Et Al → Big Diamond Coal Company; 1982-05-01 to 1983-02-28; source msha-controller-operator-history
- **operator_operates_mine:** Brown Coal Company → No 1 Slope; 1983-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Stephen  Perchinski → No 1 Slope; 1983-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Stephen  Perchinski → Brown Coal Company; 1983-03-01 to current/open; source msha-controller-operator-history