# Relationship history for MSHA mine 4200990

Current hierarchy: **Lammert Tom → Tom Lammert Mining → Monte Cristo**

- 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:** Uranium Production Company Inc → Monte Cristo; 1950-01-01 to 1978-05-18; source msha-controller-operator-history
- **controller_controls_mine:** Uranium Production Company Inc → Monte Cristo; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Uranium Production Company Inc → Uranium Production Company Inc; 1950-01-01 to 1978-05-18; source msha-controller-operator-history
- **controller_controls_mine:** Deitz Ralph K → Monte Cristo; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Larry & Jody Shumway Mining → Monte Cristo; 1978-05-19 to 1981-08-17; source msha-controller-operator-history
- **controller_controls_mine:** Shumway Larry & Jody → Monte Cristo; 1978-05-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Shumway Larry & Jody → Larry & Jody Shumway Mining; 1978-05-19 to 1981-08-17; source msha-controller-operator-history
- **operator_operates_mine:** C & D Exploration Inc → Monte Cristo; 1981-08-18 to 1983-09-25; source msha-controller-operator-history
- **controller_controls_operator:** Deitz Ralph K → C & D Exploration Inc; 1981-08-18 to 1983-09-25; source msha-controller-operator-history
- **operator_operates_mine:** Shumway Mining → Monte Cristo; 1983-09-26 to 1986-09-03; source msha-controller-operator-history
- **controller_controls_mine:** Shumway Larry & Jody → Monte Cristo; 1983-09-26 to 1986-09-03; source msha-controller-operator-history
- **controller_controls_operator:** Shumway Larry & Jody → Shumway Mining; 1983-09-26 to 1986-09-03; source msha-controller-operator-history
- **controller_controls_mine:** Lammert Tom → Monte Cristo; 1986-03-04 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Shumway Mining → Monte Cristo; 1986-09-04 to 1987-01-15; source msha-controller-operator-history
- **controller_controls_mine:** Shumway Dick & Mike → Monte Cristo; 1986-09-04 to 1987-01-15; source msha-controller-operator-history
- **controller_controls_operator:** Shumway Dick & Mike → Shumway Mining; 1986-09-04 to 1987-01-15; source msha-controller-operator-history
- **operator_operates_mine:** Tom Lammert Mining → Monte Cristo; 1987-01-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lammert Tom → Tom Lammert Mining; 1987-01-16 to current/open; source msha-controller-operator-history