# Relationship history for MSHA mine 4604829

Current hierarchy: **Wymer William O → Phoenix Collieries Company Inc → #1 Surface**

- 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:** A J Volpi Contractors Inc → #1 Surface; 1975-10-01 to 1979-06-19; source msha-controller-operator-history
- **controller_controls_mine:** Volpi A J → #1 Surface; 1975-10-01 to 1979-06-19; source msha-controller-operator-history
- **controller_controls_operator:** Volpi A J → A J Volpi Contractors Inc; 1975-10-01 to 1979-06-19; source msha-controller-operator-history
- **operator_operates_mine:** Elk Energy Inc → #1 Surface; 1979-06-20 to 1979-10-04; source msha-controller-operator-history
- **controller_controls_mine:** Cornwell J F → #1 Surface; 1979-06-20 to 1979-10-04; source msha-controller-operator-history
- **controller_controls_operator:** Cornwell J F → Elk Energy Inc; 1979-06-20 to 1979-10-04; source msha-controller-operator-history
- **operator_operates_mine:** Phoenix Collieries → #1 Surface; 1979-10-05 to 1980-01-21; source msha-controller-operator-history
- **controller_controls_mine:** Dunford J H → #1 Surface; 1979-10-05 to 1980-01-21; source msha-controller-operator-history
- **controller_controls_operator:** Dunford J H → Phoenix Collieries; 1979-10-05 to 1980-01-21; source msha-controller-operator-history
- **operator_operates_mine:** Phoenix Collieries Company Inc → #1 Surface; 1980-01-22 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Wymer William O → #1 Surface; 1980-01-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wymer William O → Phoenix Collieries Company Inc; 1980-01-22 to current/open; source msha-controller-operator-history