# Relationship history for MSHA mine 1515715

Current hierarchy: **Holst William F → Universal Minerals & Mining Corp → Mine No 1**

- 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:** U B Coal Company → Mine No 1; 1986-08-01 to 1987-05-03; source msha-controller-operator-history
- **controller_controls_mine:** Hasting Edward Et Al → Mine No 1; 1986-08-01 to 1987-05-03; source msha-controller-operator-history
- **controller_controls_operator:** Hasting Edward Et Al → U B Coal Company; 1986-08-01 to 1987-05-03; source msha-controller-operator-history
- **operator_operates_mine:** Vicmount Coal Company → Mine No 1; 1987-05-04 to 1987-11-15; source msha-controller-operator-history
- **controller_controls_mine:** Trieschman George & Dean Gibson → Mine No 1; 1987-05-04 to 1987-11-15; source msha-controller-operator-history
- **controller_controls_operator:** Trieschman George & Dean Gibson → Vicmount Coal Company; 1987-05-04 to 1987-11-15; source msha-controller-operator-history
- **controller_controls_mine:** Abrol Prem P → Mine No 1; 1987-06-29 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Lucky Star Mining Inc → Mine No 1; 1987-11-16 to 1989-04-19; source msha-controller-operator-history
- **controller_controls_operator:** Abrol Prem P → Lucky Star Mining Inc; 1987-11-16 to 1989-04-19; source msha-controller-operator-history
- **operator_operates_mine:** C & C Resources → Mine No 1; 1989-04-20 to 1990-03-22; source msha-controller-operator-history
- **controller_controls_mine:** Brock Clyde → Mine No 1; 1989-04-20 to 1990-03-22; source msha-controller-operator-history
- **controller_controls_operator:** Brock Clyde → C & C Resources; 1989-04-20 to 1990-03-22; source msha-controller-operator-history
- **controller_controls_mine:** Holst William F → Mine No 1; 1990-03-22 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Universal Minerals & Mining Corp → Mine No 1; 1990-03-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Holst William F → Universal Minerals & Mining Corp; 1990-03-23 to current/open; source msha-controller-operator-history