# Relationship history for MSHA mine 3608113

Current hierarchy: **Heidelberg Materials AG → Hanson Aggregates Pma Inc → Coraopolis 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:** Glenn I  Crain → Coraopolis Plant; 1986-03-01 to 1991-03-07; source msha-controller-operator-history
- **controller_controls_mine:** Lafarge S A → Coraopolis Plant; 1987-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Pioneer International Ltd → Coraopolis Plant; 1989-01-16 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Pittsburg Sand & Gravel Inc → Coraopolis Plant; 1989-10-01 to 1991-03-07; source msha-controller-operator-history
- **controller_controls_operator:** Glenn I  Crain → Pittsburg Sand & Gravel Inc; 1989-10-01 to 1991-03-07; source msha-controller-operator-history
- **operator_operates_mine:** Pittsburgh Sand & Gravel Inc → Coraopolis Plant; 1991-03-08 to 1991-10-02; source msha-controller-operator-history
- **controller_controls_mine:** Standard Slag Company → Coraopolis Plant; 1991-03-08 to 1991-10-02; source msha-controller-operator-history
- **controller_controls_operator:** Standard Slag Company → Pittsburgh Sand & Gravel Inc; 1991-03-08 to 1991-10-02; source msha-controller-operator-history
- **operator_operates_mine:** Lafarge Construction Materials → Coraopolis Plant; 1991-10-03 to 1996-05-15; source msha-controller-operator-history
- **controller_controls_operator:** Lafarge S A → Lafarge Construction Materials; 1991-10-03 to 1996-05-15; source msha-controller-operator-history
- **operator_operates_mine:** Davison Sand & Gravel Company → Coraopolis Plant; 1996-05-16 to 2000-08-03; source msha-controller-operator-history
- **controller_controls_operator:** Pioneer International Ltd → Davison Sand & Gravel Company; 1996-05-16 to 2000-08-03; source msha-controller-operator-history
- **operator_operates_mine:** Hanson Aggregates Pma Inc → Coraopolis Plant; 2000-08-04 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Coraopolis 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:** Heidelberg Materials AG → Coraopolis 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 current/open; source msha-controller-operator-history