# Relationship history for MSHA mine 4606192

Current hierarchy: **Black William E → Ridgeway Development Corp → 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:** Vandalie Mining Company Inc → No 1 Mine; 1980-08-01 to 1981-06-30; source msha-controller-operator-history
- **controller_controls_mine:** Smith Leonard Sr → No 1 Mine; 1980-08-01 to 1981-06-30; source msha-controller-operator-history
- **controller_controls_operator:** Smith Leonard Sr → Vandalie Mining Company Inc; 1980-08-01 to 1981-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Vandalie Mining Company Inc → No 1 Mine; 1981-07-01 to 1981-10-26; source msha-controller-operator-history
- **controller_controls_mine:** Spencer Harry → No 1 Mine; 1981-07-01 to 1981-10-26; source msha-controller-operator-history
- **controller_controls_operator:** Spencer Harry → Vandalie Mining Company Inc; 1981-07-01 to 1981-10-26; source msha-controller-operator-history
- **operator_operates_mine:** Ral Coal Company → No 1 Mine; 1981-10-27 to 1989-08-14; source msha-controller-operator-history
- **controller_controls_mine:** Ronnie  Lilly → No 1 Mine; 1981-10-27 to 1989-08-14; source msha-controller-operator-history
- **controller_controls_operator:** Ronnie  Lilly → Ral Coal Company; 1981-10-27 to 1989-08-14; source msha-controller-operator-history
- **operator_operates_mine:** Ridgeway Development Corp → No 1 Mine; 1989-08-15 to 1990-10-31; source msha-controller-operator-history
- **controller_controls_mine:** Reed George → No 1 Mine; 1989-08-15 to 1990-10-31; source msha-controller-operator-history
- **controller_controls_operator:** Reed George → Ridgeway Development Corp; 1989-08-15 to 1990-10-31; source msha-controller-operator-history
- **operator_operates_mine:** Ridgeway Development Corp → No 1 Mine; 1990-11-01 to 1991-11-26; source msha-controller-operator-history
- **controller_controls_mine:** Henry Dale  Shrewsbury → No 1 Mine; 1990-11-01 to 1991-11-26; source msha-controller-operator-history
- **controller_controls_operator:** Henry Dale  Shrewsbury → Ridgeway Development Corp; 1990-11-01 to 1991-11-26; source msha-controller-operator-history
- **controller_controls_mine:** Black William E → No 1 Mine; 1991-09-17 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Ridgeway Development Corp → No 1 Mine; 1991-11-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Black William E → Ridgeway Development Corp; 1991-11-27 to current/open; source msha-controller-operator-history