# Relationship history for MSHA mine 1510215

Current hierarchy: **Longworth G Randall → Heritage Fuel Inc → Tipple 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:** Alma Coal Corp → Tipple No 1; 1976-12-01 to 1980-04-13; source msha-controller-operator-history
- **controller_controls_mine:** Johnson R B → Tipple No 1; 1976-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Johnson R B → Alma Coal Corp; 1976-12-01 to 1980-04-13; source msha-controller-operator-history
- **operator_operates_mine:** Alma Coal Corp → Tipple No 1; 1980-04-14 to 1983-03-16; source msha-controller-operator-history
- **controller_controls_mine:** Carter William B & David → Tipple No 1; 1980-04-14 to 1983-03-20; source msha-controller-operator-history
- **controller_controls_operator:** Carter William B & David → Alma Coal Corp; 1980-04-14 to 1983-03-16; source msha-controller-operator-history
- **operator_operates_mine:** Alma Coal Corp → Tipple No 1; 1983-03-17 to 1986-10-26; source msha-controller-operator-history
- **controller_controls_mine:** Infinity Coal Corp → Tipple No 1; 1983-03-17 to 1986-10-26; source msha-controller-operator-history
- **controller_controls_operator:** Infinity Coal Corp → Alma Coal Corp; 1983-03-17 to 1986-10-26; source msha-controller-operator-history
- **operator_operates_mine:** Heritage Fuel Inc → Tipple No 1; 1986-10-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Longworth G Randall → Tipple No 1; 1986-10-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Longworth G Randall → Heritage Fuel Inc; 1986-10-27 to current/open; source msha-controller-operator-history