# Relationship history for MSHA mine 1510676

Current hierarchy: **Ronnie A  Edwards → Red Dog Coal Corp → No 1 Mine (D)**

- 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:** Murray G Dale & Jan Gorgen → No 1 Mine (D); 1977-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Little Hackney Creek Coal Company → No 1 Mine (D); 1977-08-01 to 1980-02-28; source msha-controller-operator-history
- **controller_controls_operator:** Murray G Dale & Jan Gorgen → Little Hackney Creek Coal Company; 1977-08-01 to 1980-02-28; source msha-controller-operator-history
- **controller_controls_mine:** United  Company → No 1 Mine (D); 1980-02-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Little Hackney Creek Coal Company → No 1 Mine (D); 1980-02-29 to 1981-05-13; source msha-controller-operator-history
- **controller_controls_operator:** United  Company → Little Hackney Creek Coal Company; 1980-02-29 to 1981-05-13; source msha-controller-operator-history
- **controller_controls_mine:** Smith David → No 1 Mine (D); 1980-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Helmandollar Sam → No 1 Mine (D); 1981-04-30 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Snowball Coal Corp → No 1 Mine (D); 1981-05-14 to 1981-09-02; source msha-controller-operator-history
- **controller_controls_operator:** Smith David → Snowball Coal Corp; 1981-05-14 to 1981-09-02; source msha-controller-operator-history
- **operator_operates_mine:** Dial Rock Coal Corp → No 1 Mine (D); 1981-09-03 to 1981-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Helmandollar Sam → Dial Rock Coal Corp; 1981-09-03 to 1981-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Red Dog Coal Corp → No 1 Mine (D); 1982-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ronnie A  Edwards → No 1 Mine (D); 1982-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ronnie A  Edwards → Red Dog Coal Corp; 1982-01-01 to current/open; source msha-controller-operator-history