# Relationship history for MSHA mine 0504108

Current hierarchy: **Tiefel Douglas A → Goose Haven Sand & Gravel Inc → Goose Haven Adams County 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

- **controller_controls_mine:** David B  Nystrom → Goose Haven Adams County Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Tiefel Douglas A → Goose Haven Adams County Pit; 1985-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Goose Haven Sand & Gravel Inc → Goose Haven Adams County Pit; 1986-01-01 to 1986-06-24; source msha-controller-operator-history
- **controller_controls_operator:** Tiefel Douglas A → Goose Haven Sand & Gravel Inc; 1986-01-01 to 1986-06-24; source msha-controller-operator-history
- **operator_operates_mine:** C & M Sand & Gravel → Goose Haven Adams County Pit; 1986-06-25 to 1988-03-13; source msha-controller-operator-history
- **controller_controls_operator:** David B  Nystrom → C & M Sand & Gravel; 1986-06-25 to 1988-03-13; source msha-controller-operator-history
- **operator_operates_mine:** Goose Haven Sand & Gravel Inc → Goose Haven Adams County Pit; 1988-03-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tiefel Douglas A → Goose Haven Sand & Gravel Inc; 1988-03-14 to current/open; source msha-controller-operator-history