Operations are events that change the soil, vegetation, or residue.
	Typically human activity, but can animal, like grazing removing aboveground biomass, or natural like frost killing vegetation.
	Operations are described with effects.
	Sequence of effects critical.
	Stick with the NRCS database.
	If new new operations, must be created, follow the NRCS core database for cropland.  Consult with RUSLE2 developers for core data for other land uses.