You may want to look at U of South Carolina. Their Honors College is one of the top public Honors Colleges in the country (would need to apply as acceptance is not automatic, but your stats would make it worth a try). You would very likely get in-state tuition plus an add’l $500 to $4,000 per year, bringing your cost for tuition, fees, room and board to $20,000 to $24,000 (based on 2015-16 prices). I don’t know how strong their Environmental majors are, but the campus is lovely and there are many OOS students so you would not feel out of place.