I'm an RN. I work at a clinic in St Helens, OR. We do primary care and some other stuff. I was just awarded last year.
I did figure out the above question. You can have your payroll person calculate it and then you have to pay the Oregon taxes out of your regular paycheck. There's a form you can fill out to have them take out the exact extra amount you need to pay. You can't pay it from your monthly allotment from the Nurse Corps.