# Relationship history for MSHA mine 3604287

Current hierarchy: **Heidelberg Materials AG → Hanson Aggregates BMC, Inc → Torrance 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

- **operator_operates_mine:** Warner Company → Torrance Plant; 1950-01-01 to 1985-08-07; source msha-controller-operator-history
- **controller_controls_mine:** Warner Company → Torrance Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Warner Company → Warner Company; 1950-01-01 to 1985-08-07; source msha-controller-operator-history
- **controller_controls_mine:** F R G Industries Inc → Torrance Plant; 1979-01-01 to 1989-01-15; source msha-controller-operator-history
- **operator_operates_mine:** Davison Stone Company → Torrance Plant; 1985-08-08 to 1989-01-15; source msha-controller-operator-history
- **controller_controls_operator:** F R G Industries Inc → Davison Stone Company; 1985-08-08 to 1989-01-15; source msha-controller-operator-history
- **operator_operates_mine:** Pioneer Mid-Atlantic Inc → Torrance Plant; 1989-01-16 to 2000-08-03; source msha-controller-operator-history
- **controller_controls_mine:** Pioneer International Ltd → Torrance Plant; 1989-01-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Pioneer International Ltd → Pioneer Mid-Atlantic Inc; 1989-01-16 to 2000-08-03; source msha-controller-operator-history
- **controller_controls_mine:** USS Holdings Inc → Torrance Plant; 1996-03-09 to 2003-07-18; source msha-controller-operator-history
- **operator_operates_mine:** Hanson Aggregates Pma Inc → Torrance Plant; 2000-08-04 to 2008-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Torrance Plant; 2000-08-04 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Hanson Aggregates Pma Inc; 2000-08-04 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Torrance Plant; 2003-07-19 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → Torrance Plant; 2007-08-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Hanson Aggregates Pma Inc; 2007-08-23 to 2008-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Hanson Aggregates BMC, Inc → Torrance Plant; 2009-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Hanson Aggregates BMC, Inc; 2009-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Hanson Aggregates BMC, Inc; 2009-01-01 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_operator:** USS Holdings Inc → Hanson Aggregates BMC, Inc; 2009-01-01 to 2003-07-18; source msha-controller-operator-history