Figure 1. Soil regions of Ohio.
Figure 1. Soil regions of Ohio.
Soils are highly variable in space and also change with time, through natural processes, and with human management. Soil conditions change along with subtle changes in landscape and environmental conditions. Human activities frequently change local soil conditions. The local variability of soil attributes must be understood in order to design an appropriate onsite wastewater treatment system. Soil survey maps (Figure 1) and reports are useful tools to indicate general conditions expected in an area, but they cannot capture all the local diversity in soil conditions, or changes that have occurred since mapping was completed. Site specific observations by a qualified, experienced practitioner are essential for understanding the fine-scale local variability of soil properties and local site conditions.