# Relationship history for MSHA mine 4400164

Current hierarchy: **CRH PLC → Appalachian Aggregates, LLC → Glade Stone 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:** D W L Inc → Glade Stone Plant; 1950-01-01 to 1998-12-31; source msha-controller-operator-history
- **controller_controls_mine:** W-L Construction & Paving Inc → Glade Stone Plant; 1950-01-01 to 1998-12-31; source msha-controller-operator-history
- **controller_controls_operator:** W-L Construction & Paving Inc → D W L Inc; 1950-01-01 to 1998-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Boxley Materials Co → Glade Stone Plant; 1991-03-01 to 2015-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Glade Stone Inc → Glade Stone Plant; 1999-01-01 to 2006-01-24; source msha-controller-operator-history
- **controller_controls_mine:** Steve L  Lawson et al → Glade Stone Plant; 1999-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Steve L  Lawson et al → Glade Stone Inc; 1999-01-01 to 2006-01-24; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Glade Stone Plant; 2006-01-23 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Mountain Materials, Inc. → Glade Stone Plant; 2006-01-25 to 2020-12-31; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Mountain Materials, Inc.; 2006-01-25 to 2020-12-31; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Glade Stone Plant; 2016-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Appalachian Aggregates, LLC → Glade Stone Plant; 2021-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Boxley Materials Co → Appalachian Aggregates, LLC; 2021-01-01 to 2015-12-31; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Appalachian Aggregates, LLC; 2021-01-01 to current/open; source msha-controller-operator-history