# Relationship history for MSHA mine 1200023

Current hierarchy: **The Heritage Group → US Aggregates LLC → Delphi Plant**

- 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:** The Heritage Group → Delphi Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Delphi Limestone Inc → Delphi Plant; 1950-01-01 to 1988-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Joe A  Mayfield → Delphi Plant; 1950-01-01 to 1988-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Joe A  Mayfield → Delphi Limestone Inc; 1950-01-01 to 1988-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Carroll County Limestone Inc → Delphi Plant; 1989-01-01 to 1993-08-19; source msha-controller-operator-history
- **controller_controls_mine:** Shand Investments Inc → Delphi Plant; 1989-01-01 to 1993-08-19; source msha-controller-operator-history
- **controller_controls_operator:** Shand Investments Inc → Carroll County Limestone Inc; 1989-01-01 to 1993-08-19; source msha-controller-operator-history
- **controller_controls_mine:** The Heritage Group → Delphi Plant; 1989-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** US Aggregates, Inc. → Delphi Plant; 1993-08-20 to 2026-06-17; source msha-controller-operator-history
- **controller_controls_operator:** The Heritage Group → US Aggregates, Inc.; 1993-08-20 to 2026-06-17; source msha-controller-operator-history
- **operator_operates_mine:** US Aggregates LLC → Delphi Plant; 2026-06-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** The Heritage Group → US Aggregates LLC; 2026-06-18 to current/open; source msha-controller-operator-history