# Relationship history for MSHA mine 4001405

Current hierarchy: **Alan  Dement → Delta Contracting Company LLC → Jackson Sand 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

- **controller_controls_mine:** Mc Dowell Enterprises → Jackson Sand Plant; 1950-01-01 to 1985-12-01; source msha-controller-operator-history
- **operator_operates_mine:** Mc Dowell Materials Corp → Jackson Sand Plant; 1979-01-01 to 1984-09-30; source msha-controller-operator-history
- **controller_controls_operator:** Mc Dowell Enterprises → Mc Dowell Materials Corp; 1979-01-01 to 1984-09-30; source msha-controller-operator-history
- **operator_operates_mine:** Dement Construction Company → Jackson Sand Plant; 1984-10-01 to 2007-03-31; source msha-controller-operator-history
- **controller_controls_mine:** William D  Dement → Jackson Sand Plant; 1984-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** William D  Dement → Dement Construction Company; 1984-10-01 to 2007-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Delta Contracting Company LLC → Jackson Sand Plant; 2007-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** W G  Dement Jr → Jackson Sand Plant; 2007-04-01 to 2018-08-31; source msha-controller-operator-history
- **controller_controls_operator:** W G  Dement Jr → Delta Contracting Company LLC; 2007-04-01 to 2018-08-31; source msha-controller-operator-history
- **controller_controls_mine:** Alan  Dement → Jackson Sand Plant; 2018-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alan  Dement → Delta Contracting Company LLC; 2018-09-01 to current/open; source msha-controller-operator-history