The ILS at ACV has minimums of 1800' runway visual range (RVR). That is between 1/4 and 1/2 mile. Reported ceiling is not controlling.
Takeoff minimums are lower (less restrictive) than landing minimums.
I don't have access to the Jepp charts for ACV so don't know if there's an special authorization approach to the airport that Skywest might be able to use. I didn't see anything in the government charts to indicate that there is.