# Relationship history for MSHA mine 1504401

Current hierarchy: **Dotson Andy → Dotson Coal Co 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:** Island Creek Coal Company → No 1 Mine; 1950-01-01 to 1973-04-30; source msha-controller-operator-history
- **controller_controls_mine:** Occidental Petroleum Corp → No 1 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Occidental Petroleum Corp → Island Creek Coal Company; 1950-01-01 to 1973-04-30; source msha-controller-operator-history
- **operator_operates_mine:** Lea Coal Company → No 1 Mine; 1973-05-01 to 1974-02-05; source msha-controller-operator-history
- **controller_controls_mine:** Lea Coal Company → No 1 Mine; 1973-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lea Coal Company → Lea Coal Company; 1973-05-01 to 1974-02-05; source msha-controller-operator-history
- **operator_operates_mine:** B & V Coal Company → No 1 Mine; 1974-02-06 to 1974-04-30; source msha-controller-operator-history
- **controller_controls_mine:** B & V Coal Company → No 1 Mine; 1974-02-06 to 1974-04-30; source msha-controller-operator-history
- **controller_controls_operator:** B & V Coal Company → B & V Coal Company; 1974-02-06 to 1974-04-30; source msha-controller-operator-history
- **operator_operates_mine:** Big Hurricane Coal Co Inc → No 1 Mine; 1974-05-01 to 1975-09-02; source msha-controller-operator-history
- **controller_controls_mine:** Walker Charles E → No 1 Mine; 1974-05-01 to 1975-09-02; source msha-controller-operator-history
- **controller_controls_operator:** Walker Charles E → Big Hurricane Coal Co Inc; 1974-05-01 to 1975-09-02; source msha-controller-operator-history
- **controller_controls_mine:** Dotson Andy → No 1 Mine; 1975-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Dotson Coal Co Inc → No 1 Mine; 1975-09-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dotson Andy → Dotson Coal Co Inc; 1975-09-03 to current/open; source msha-controller-operator-history