# Relationship history for MSHA mine 4603970

Current hierarchy: **Groves S J & Sons Company → Gopher Mining Company → Dicha 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Mc Kee Ralph → Dicha No 1 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Wyoming Mining Company Inc → Dicha No 1 Mine; 1974-04-01 to 1974-10-14; source msha-controller-operator-history
- **controller_controls_operator:** Mc Kee Ralph → Wyoming Mining Company Inc; 1974-04-01 to 1974-10-14; source msha-controller-operator-history
- **controller_controls_mine:** Groves S J & Sons Company → Dicha No 1 Mine; 1974-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Impco-Springdale Fuels Company → Dicha No 1 Mine; 1974-10-15 to 1976-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Impco-International Mining & Petroleum Co → Dicha No 1 Mine; 1974-10-15 to 1976-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Impco-International Mining & Petroleum Co → Impco-Springdale Fuels Company; 1974-10-15 to 1976-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Manlo Mining Company Inc → Dicha No 1 Mine; 1977-01-01 to 1977-11-09; source msha-controller-operator-history
- **controller_controls_mine:** Mansfield John → Dicha No 1 Mine; 1977-01-01 to 1978-06-25; source msha-controller-operator-history
- **controller_controls_operator:** Mansfield John → Manlo Mining Company Inc; 1977-01-01 to 1977-11-09; source msha-controller-operator-history
- **operator_operates_mine:** Gopher Mining Company → Dicha No 1 Mine; 1977-11-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Groves S J & Sons Company → Gopher Mining Company; 1977-11-10 to current/open; source msha-controller-operator-history