Master horizon for fill

The quick question: What horizon designation or horizonation are people using for describing human transported fill (artificial
fill)? In Massachusetts we are involved with numerous projects such as stormwater, onsite sewage training, wetland
restoration, mapping, etc. which requires us to log test pits in disturbed areas. Rather than calling the fill a C horizon, I use an F
horizon (F for Fill) to differentiate fill from the natural geologic material or buried soil horizons which may or may not be
present.

The problem with using a C horizon for fill is that the description may mislead some people interpreting the profile description.
In Massachusetts, the USDA method for describing soils (horizons, texture, etc.) is the approved method for the on-site sewage
code and wetland delineation manual. A part of the on-site code calls for 4 feet of naturally occurring geologic material (C
horizon) required for a site to be suitable for an onsite system. If you log a pit that has fill overlying the buried soil and use a C
for the fill the health agent may think the C is naturally occuring and ok the fill to be used. The same applies for hydric
descriptions in altered areas, using a C for the fill may be misinterpreted as an alluvial deposition and not human transported
material.

Are there any thoughts on developing a Master horizon for fill? My vote is an F horizon. Pictures of some of our fill soils
(Psamments, and Aquents) can be found on the Plymouth County Soil Survey Homepage (http://members.aol.com/plysoil).