# Relationship history for MSHA mine 3101871

Current hierarchy: **Heidelberg Materials AG → Heidelberg Materials Southeast Agg. LLC → Gardner Quarry**

- 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:** J Chris  Swift → Gardner Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Becker Sand & Gravel Company Inc → Gardner Quarry; 1979-01-01 to 1986-02-27; source msha-controller-operator-history
- **controller_controls_operator:** J Chris  Swift → Becker Sand & Gravel Company Inc; 1979-01-01 to 1986-02-27; source msha-controller-operator-history
- **operator_operates_mine:** Becker Minerals Inc → Gardner Quarry; 1986-02-28 to 1999-04-11; source msha-controller-operator-history
- **controller_controls_mine:** Alfred Mc Alpine Inc → Gardner Quarry; 1986-02-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alfred Mc Alpine Inc → Becker Minerals Inc; 1986-02-28 to 1999-04-11; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Gardner Quarry; 1988-11-14 to 2007-08-22; source msha-controller-operator-history
- **operator_operates_mine:** Hanson Aggregates Becker Incorrporated → Gardner Quarry; 1999-04-12 to 2002-05-07; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Gardner Quarry; 1999-04-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Hanson Aggregates Becker Incorrporated; 1999-04-12 to 2002-05-07; source msha-controller-operator-history
- **operator_operates_mine:** Heidelberg Materials Southeast Agg. LLC → Gardner Quarry; 2002-05-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Heidelberg Materials Southeast Agg. LLC; 2002-05-08 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → Gardner Quarry; 2007-08-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Heidelberg Materials Southeast Agg. LLC; 2007-08-23 to current/open; source msha-controller-operator-history