# Relationship history for MSHA mine 1202217

Current hierarchy: **Heidelberg Materials AG → Hanson Aggregates Midwest, LLC → Harding Street Sand & Gravel**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Hanson PLC → Harding Street Sand & Gravel; 1988-11-14 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_mine:** The Heritage Group → Harding Street Sand & Gravel; 1989-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Harco Sand & Gravel → Harding Street Sand & Gravel; 1997-06-01 to 2009-12-22; source msha-controller-operator-history
- **controller_controls_mine:** Paul G  Harding → Harding Street Sand & Gravel; 1997-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Paul G  Harding → Harco Sand & Gravel; 1997-06-01 to 2009-12-22; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → Harding Street Sand & Gravel; 2007-08-23 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Heritage Aggregates LLC → Harding Street Sand & Gravel; 2009-12-23 to 2011-06-30; source msha-controller-operator-history
- **controller_controls_operator:** The Heritage Group → Heritage Aggregates LLC; 2009-12-23 to 2011-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Hanson Aggregates Midwest, LLC → Harding Street Sand & Gravel; 2011-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Hanson Aggregates Midwest, LLC; 2011-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Hanson Aggregates Midwest, LLC; 2011-07-01 to 2007-08-22; source msha-controller-operator-history