Appendix 7. Counted soil disturbance categories and recommended limits according to hazard ratings

a Assessing the hazards for soil compaction, soil displacement, and soil erosion need not be done if the harvesting method is cable or aerial.

b Under the "Categories counted" column, the term "Always" includes soil disturbance that is always counted, namely excavated or bladed trails, corduroyed trails, 15-cm-deep ruts, deep gouges, long gouges, wide gouges, very wide scalps. The meaning of the other symbols are: "S": wide scalps; "T5": 5-cm-deep ruts; "E": repeated machine traffic; and "A": compacted areas.

Combine the categories measured for different hazard ratings if that will result in more categories being counted or a lower allowable disturbance limit. For example, on a site with a Very High compaction hazard and a High surface erosion hazard, the categories counted are "Always + S + E + A + T5," the soil disturbance limit would be 5%.