Output coordinate system for my area does not reference to US Survey Feet, only meters (UTM Zone 55N, Guam). My customer would like me to produce contour elevation output data in feet, not meters, at 1’ ft intervals. Am able to select contour data inputs in Processing Options but only for meters. Need help! 
Would you please click “project” and “select output coordinate system…” (see image 1), change the unit (see image 2), and see if it works?
Image 1
Image 2
Yes, when the project was set up originally I tried that. Selecting “Feet” from “Meters” changes to a coordinate system that I am unfamiliar with and isn’t used in my region.
Yuka, I stand corrected. Was able to convert to survey feet in this coordinate system. Easy fix; thank you.
Thank you for letting us know!