Have sinus surgery next week. i work outdoors in a wooded area 2 hours a day and have seasonal allergies. will allergy cause sinus be blocked up again?

Yes: The swollen turbinates are common causes for sinus blockage leading to infection. Without controlling the nasal congestion, you will likely get infection again after a few months of initial improvement from the surgery. Get a 2nd opinion before getting any surgery done. In your case, I'd recommend that you consult an allergist before surgery which is 50% effective at best. .