Building an indoor in CO, need footing direction

Hi all, we are building a small indoor arena (private farm), and I am looking for direction on how to plan the base, select footing, etc. The usage will be mostly dressage with a bit of jumping. It is very dry here, and arena will not be heated or watered, so I’m very interested in whatever footing strategy will be lowest dust and lowest maintenance, even if it is pricier. We are in Colorado. Thoughts? TIA!