# Relationship history for MSHA mine 1300725

Current hierarchy: **Manatts Enterprises; Cedar Valley Corp → BMC Aggregates LC → Waterloo Sand**

- 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:** Martin Marietta Aggregates → Waterloo Sand; 1950-01-01 to 1982-11-28; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Waterloo Sand; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Aggregates; 1950-01-01 to 1982-11-28; source msha-controller-operator-history
- **operator_operates_mine:** Basic Materials Corp → Waterloo Sand; 1982-11-29 to 2006-07-31; source msha-controller-operator-history
- **controller_controls_mine:** Cedar Valley Corp  et al → Waterloo Sand; 1982-11-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cedar Valley Corp  et al → Basic Materials Corp; 1982-11-29 to 2006-07-31; source msha-controller-operator-history
- **controller_controls_operator:** Manatts Enterprises et al → Basic Materials Corp; 1982-11-29 to 2006-07-31; source msha-controller-operator-history
- **operator_operates_mine:** BMC Aggregates LC → Waterloo Sand; 2006-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Manatts Enterprises et al → Waterloo Sand; 2006-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Manatts Enterprises et al → BMC Aggregates LC; 2006-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cedar Valley Corp  et al → BMC Aggregates LC; 2006-08-01 to current/open; source msha-controller-operator-history