# Relationship history for MSHA mine 1401757

Current hierarchy: **Tod  Roberg → American Sand & Gravel, LLC → Waterwell**

- 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:** Dane Q  Barclay et al → Waterwell; 1950-01-01 to 2017-05-10; source msha-controller-operator-history
- **operator_operates_mine:** Alsop Sand Co., Inc. → Waterwell; 2013-03-08 to 2019-06-12; source msha-controller-operator-history
- **controller_controls_operator:** Dane Q  Barclay et al → Alsop Sand Co., Inc.; 2013-03-08 to 2017-05-10; source msha-controller-operator-history
- **controller_controls_operator:** David H  Barclay et al → Alsop Sand Co., Inc.; 2013-03-08 to 2017-05-10; source msha-controller-operator-history
- **controller_controls_mine:** Dane Q Barclay → Waterwell; 2017-05-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dane Q Barclay → Alsop Sand Co., Inc.; 2017-05-11 to 2019-06-12; source msha-controller-operator-history
- **operator_operates_mine:** American Sand & Gravel, LLC → Waterwell; 2019-06-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Tod  Roberg → Waterwell; 2019-06-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tod  Roberg → American Sand & Gravel, LLC; 2019-06-13 to current/open; source msha-controller-operator-history