You won t have any problem with the legality of the shifts, but I don t know too many people who would like those long breaks between shifts. Although if the price is right, people will work. I attached a link to the Oregon DOL wage division.
Your problem is going to be with lunch and breaks. Those are federal laws not state ones. If it is just you working then no problem. But you will definitely want to change this schedule if you are going to have employees. Also, if you re going to have employees you ll need to add workers comp and unemployment costs to your calculations.
