# Relationship history for MSHA mine 1201942

Current hierarchy: **Vulcan Materials Company → Vulcan Materials Company → Ac Cone Crusher #185**

- 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:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → Ac Cone Crusher #185; 1950-01-01 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_mine:** Wayne  Klink JR → Ac Cone Crusher #185; 1978-11-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Harmening Edwin V → Ac Cone Crusher #185; 1981-08-28 to 1985-04-29; source msha-controller-operator-history
- **operator_operates_mine:** Old Indian Materials Corp → Ac Cone Crusher #185; 1984-06-01 to 1985-04-29; source msha-controller-operator-history
- **controller_controls_operator:** Harmening Edwin V → Old Indian Materials Corp; 1984-06-01 to 1985-04-29; source msha-controller-operator-history
- **operator_operates_mine:** State Line Sand & Gravel Inc → Ac Cone Crusher #185; 1985-04-30 to 1988-03-31; source msha-controller-operator-history
- **controller_controls_operator:** Wayne  Klink JR → State Line Sand & Gravel Inc; 1985-04-30 to 1988-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Richard L  Sibert → Ac Cone Crusher #185; 1988-02-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** State Line Sand & Gravel Inc → Ac Cone Crusher #185; 1988-04-01 to 1991-02-28; source msha-controller-operator-history
- **controller_controls_operator:** Richard L  Sibert → State Line Sand & Gravel Inc; 1988-04-01 to 1991-02-28; source msha-controller-operator-history
- **operator_operates_mine:** Vulcan Materials Company → Ac Cone Crusher #185; 1991-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → Vulcan Materials Company; 1991-03-01 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_mine:** Vulcan Materials Company → Ac Cone Crusher #185; 2007-11-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vulcan Materials Company → Vulcan Materials Company; 2007-11-16 to current/open; source msha-controller-operator-history