# Relationship history for MSHA mine 1515152

Current hierarchy: **John M  Potter; Thomas A  Potter → Sunny Ridge Mining Company Inc → Sunny Ridge Mining Job No 86**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Phelps Resources Inc → Sunny Ridge Mining Job No 86; 1985-04-01 to 1991-08-04; source msha-controller-operator-history
- **controller_controls_mine:** Hatfield Woodrow-Ermel Et Al → Sunny Ridge Mining Job No 86; 1985-04-01 to 1991-08-04; source msha-controller-operator-history
- **controller_controls_operator:** Hatfield Woodrow-Ermel Et Al → Phelps Resources Inc; 1985-04-01 to 1991-08-04; source msha-controller-operator-history
- **controller_controls_mine:** Thomas A  Potter et al → Sunny Ridge Mining Job No 86; 1987-09-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Nick Processing Inc → Sunny Ridge Mining Job No 86; 1991-08-05 to 1995-05-02; source msha-controller-operator-history
- **controller_controls_mine:** Sands Jeffrey → Sunny Ridge Mining Job No 86; 1991-08-05 to 1995-05-02; source msha-controller-operator-history
- **controller_controls_operator:** Sands Jeffrey → Nick Processing Inc; 1991-08-05 to 1995-05-02; source msha-controller-operator-history
- **operator_operates_mine:** Sunny Ridge Mining Company Inc → Sunny Ridge Mining Job No 86; 1995-05-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thomas A  Potter et al → Sunny Ridge Mining Company Inc; 1995-05-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John M  Potter et al → Sunny Ridge Mining Company Inc; 1995-05-03 to current/open; source msha-controller-operator-history