# Relationship history for MSHA mine 1401746

Current hierarchy: **Mitchell A  Opat; Mark E  Opat → E-M Sand & Gravel LLC → McPherson Mine**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Dane Q  Barclay et al → McPherson Mine; 1950-01-01 to 2017-05-10; source msha-controller-operator-history
- **operator_operates_mine:** Alsop Sand Co., Inc. → McPherson Mine; 2012-04-04 to 2017-07-09; source msha-controller-operator-history
- **controller_controls_operator:** Dane Q  Barclay et al → Alsop Sand Co., Inc.; 2012-04-04 to 2017-05-10; source msha-controller-operator-history
- **controller_controls_operator:** David H  Barclay et al → Alsop Sand Co., Inc.; 2012-04-04 to 2017-05-10; source msha-controller-operator-history
- **controller_controls_mine:** Dane Q Barclay → McPherson Mine; 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 2017-07-09; source msha-controller-operator-history
- **operator_operates_mine:** E-M Sand & Gravel LLC → McPherson Mine; 2017-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mitchell A  Opat et al → McPherson Mine; 2017-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mitchell A  Opat et al → E-M Sand & Gravel LLC; 2017-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mark E  Opat et al → E-M Sand & Gravel LLC; 2017-07-10 to current/open; source msha-controller-operator-history