# Relationship history for MSHA mine 3605739

Current hierarchy: **Shear Hal B & Richard B Shepperson → Tamaqua Anthracite Company → Trevorton Strip**

- 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:** Ronald  Lickman → Trevorton Strip; 1975-09-09 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** John Galt Energy Corp → Trevorton Strip; 1975-10-08 to 1976-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Ronald  Lickman → John Galt Energy Corp; 1975-10-08 to 1976-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Pinto Coal Company Inc → Trevorton Strip; 1977-01-01 to 1978-10-11; source msha-controller-operator-history
- **controller_controls_mine:** Lotzi Frank → Trevorton Strip; 1977-01-01 to 1978-10-11; source msha-controller-operator-history
- **controller_controls_operator:** Lotzi Frank → Pinto Coal Company Inc; 1977-01-01 to 1978-10-11; source msha-controller-operator-history
- **controller_controls_mine:** Larry  Gordon → Trevorton Strip; 1977-12-14 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Churchill Coal Corp → Trevorton Strip; 1978-10-12 to 1985-11-11; source msha-controller-operator-history
- **controller_controls_operator:** Larry  Gordon → Churchill Coal Corp; 1978-10-12 to 1985-11-11; source msha-controller-operator-history
- **controller_controls_mine:** Shear Hal B & Richard B Shepperson → Trevorton Strip; 1985-04-22 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Tamaqua Anthracite Company → Trevorton Strip; 1985-11-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Shear Hal B & Richard B Shepperson → Tamaqua Anthracite Company; 1985-11-12 to current/open; source msha-controller-operator-history