# Relationship history for MSHA mine 2800979

Current hierarchy: **Brad L Preston; Greg A Preston → Raymond Preston Inc. → Preston Pit**

- 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:** Sahara Sand Of Millstone Inc → Preston Pit; 1986-01-01 to 2010-04-27; source msha-controller-operator-history
- **controller_controls_mine:** Laurence J  Silvi II  Et Al → Preston Pit; 1986-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Laurence J  Silvi II  Et Al → Sahara Sand Of Millstone Inc; 1986-01-01 to 2010-04-27; source msha-controller-operator-history
- **controller_controls_operator:** John L  Silvi  Et Al → Sahara Sand Of Millstone Inc; 1986-01-01 to 2010-04-27; source msha-controller-operator-history
- **operator_operates_mine:** Raymond Preston Inc. → Preston Pit; 2010-04-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Greg A Preston et al → Preston Pit; 2010-04-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Greg A Preston et al → Raymond Preston Inc.; 2010-04-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Brad L Preston et al → Raymond Preston Inc.; 2010-04-28 to current/open; source msha-controller-operator-history