# Relationship history for MSHA mine 1515348

Current hierarchy: **Great Western Resources Inc → New Horizons Coal Inc → Upper Mason #1**

- 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:** Bobby Joe  Hensley → Upper Mason #1; 1982-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Day Branch Coal Company Inc → Upper Mason #1; 1985-09-01 to 1993-06-03; source msha-controller-operator-history
- **controller_controls_operator:** Bobby Joe  Hensley → Day Branch Coal Company Inc; 1985-09-01 to 1993-06-03; source msha-controller-operator-history
- **controller_controls_mine:** Great Western Resources Inc → Upper Mason #1; 1987-02-04 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bailey Toby & Teddy Et Al → Upper Mason #1; 1993-04-15 to 1995-01-04; source msha-controller-operator-history
- **operator_operates_mine:** Mt Top Inc → Upper Mason #1; 1993-06-04 to 1994-06-19; source msha-controller-operator-history
- **controller_controls_operator:** Bailey Toby & Teddy Et Al → Mt Top Inc; 1993-06-04 to 1994-06-19; source msha-controller-operator-history
- **operator_operates_mine:** New Horizons Coal Inc → Upper Mason #1; 1994-06-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Great Western Resources Inc → New Horizons Coal Inc; 1994-06-20 to current/open; source msha-controller-operator-history