# Relationship history for MSHA mine 4402409

Current hierarchy: **Adams Construction Company → Adams Construction Co → Thompson's 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

- **operator_operates_mine:** South Central Sand Inc → Thompson's Sand Plant; 1950-01-01 to 1998-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Marshall Daniel Webster Iii → Thompson's Sand Plant; 1950-01-01 to 1998-03-31; source msha-controller-operator-history
- **controller_controls_operator:** Marshall Daniel Webster Iii → South Central Sand Inc; 1950-01-01 to 1998-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Adams Construction Company → Thompson's Sand Plant; 1983-08-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Eden Sand Company Inc → Thompson's Sand Plant; 1998-04-01 to 2001-06-27; source msha-controller-operator-history
- **controller_controls_mine:** Boxley Materials Co → Thompson's Sand Plant; 1998-04-01 to 2001-06-27; source msha-controller-operator-history
- **controller_controls_operator:** Boxley Materials Co → Eden Sand Company Inc; 1998-04-01 to 2001-06-27; source msha-controller-operator-history
- **controller_controls_mine:** E Scott  Thompson → Thompson's Sand Plant; 1998-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Thompson's Inc Of Danville VA → Thompson's Sand Plant; 2001-06-28 to 2007-01-08; source msha-controller-operator-history
- **controller_controls_operator:** E Scott  Thompson → Thompson's Inc Of Danville VA; 2001-06-28 to 2007-01-08; source msha-controller-operator-history
- **operator_operates_mine:** Adams Construction Co → Thompson's Sand Plant; 2007-01-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Adams Construction Company → Adams Construction Co; 2007-01-09 to current/open; source msha-controller-operator-history