Friction factor for underground piping.

I am looking for a resource that describes the different friction coefficients for various soil types. I have what might be described as loose silica (i.e. sandy) soil. The pipe is 8" A53 STD with an epoxy coating so it should be fairly low friction against the sand. I doubt I will find a friction factor for 'expoxy coated pipe on silica' but I would be happy to use the higher friction factor for just the pipe if I could find it. Any information would be welcomed. Thanks again!


-Nick

Ah, seems I have answered my own question by looking through chapter 11 of the user manual. Sorry everyone!