# Relationship history for MSHA mine 1502730

Current hierarchy: **Smith Kenny L → Phelps Mining Inc → No 1 Mine**

- 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:** Duncan Coal Company → No 1 Mine; 1950-01-01 to 1972-10-24; source msha-controller-operator-history
- **controller_controls_mine:** Mullins Jack → No 1 Mine; 1950-01-01 to 1972-10-24; source msha-controller-operator-history
- **controller_controls_operator:** Mullins Jack → Duncan Coal Company; 1950-01-01 to 1972-10-24; source msha-controller-operator-history
- **operator_operates_mine:** Solomon Coal Company → No 1 Mine; 1972-10-25 to 1975-11-01; source msha-controller-operator-history
- **controller_controls_mine:** Stevens Mont → No 1 Mine; 1972-10-25 to 1975-11-01; source msha-controller-operator-history
- **controller_controls_operator:** Stevens Mont → Solomon Coal Company; 1972-10-25 to 1975-11-01; source msha-controller-operator-history
- **operator_operates_mine:** Phelps Mining Inc → No 1 Mine; 1975-11-02 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Smith Kenny L → No 1 Mine; 1975-11-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Smith Kenny L → Phelps Mining Inc; 1975-11-02 to current/open; source msha-controller-operator-history