# Relationship history for MSHA mine 2103155

Current hierarchy: **David K  Dunham; Velma M  Dunham → Dunham Gravel Inc → Dunham Gravel Co**

- 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:** Dunham Gravel, Inc. → Dunham Gravel Co; 1998-05-01 to 2015-04-22; source msha-controller-operator-history
- **controller_controls_mine:** Velma M  Dunham  et al → Dunham Gravel Co; 1998-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Velma M  Dunham  et al → Dunham Gravel, Inc.; 1998-05-01 to 2015-04-22; source msha-controller-operator-history
- **controller_controls_operator:** David K  Dunham  et al → Dunham Gravel, Inc.; 1998-05-01 to 2015-04-22; source msha-controller-operator-history
- **controller_controls_mine:** Jeff T  Rehder et al → Dunham Gravel Co; 2015-03-31 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Summit Sand & Gravel → Dunham Gravel Co; 2015-04-23 to 2015-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Jeff T  Rehder et al → Summit Sand & Gravel; 2015-04-23 to 2015-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Christopher C  West et al → Summit Sand & Gravel; 2015-04-23 to 2015-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Dunham Gravel Inc → Dunham Gravel Co; 2016-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Velma M  Dunham  et al → Dunham Gravel Inc; 2016-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David K  Dunham  et al → Dunham Gravel Inc; 2016-01-01 to current/open; source msha-controller-operator-history