# Relationship history for MSHA mine 1900007

Current hierarchy: **CRH PLC → P J Keating Company → Dracut 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:** Keating Materials Corp → Dracut Plant; 1977-10-01 to 1994-10-30; source msha-controller-operator-history
- **controller_controls_mine:** P J Keating Company → Dracut Plant; 1977-10-01 to 1994-10-30; source msha-controller-operator-history
- **controller_controls_operator:** P J Keating Company → Keating Materials Corp; 1977-10-01 to 1994-10-30; source msha-controller-operator-history
- **operator_operates_mine:** P J Keating Company → Dracut Plant; 1994-10-31 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Dracut Plant; 1994-10-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → P J Keating Company; 1994-10-31 to current/open; source msha-controller-operator-history