Which soil group corresponds to LTAR range 0.8 - 0.6 gpd/ft2?

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Multiple Choice

Which soil group corresponds to LTAR range 0.8 - 0.6 gpd/ft2?

Long-term infiltration rate (LTAR) shows how much wastewater a soil can accept per square foot over time, guiding the size of the drain field. A range of 0.8 to 0.6 gpd/ft2 sits right in the middle of the spectrum, indicating a moderate infiltration capacity. That mid-range is designated as Soil Group II, which has neither the high permeability of the best soils nor the low permeability of the poorest soils. Soils with higher LTAR (Group I) would allow more flow per area and generally require less drain-field area, while soils with lower LTAR (Groups III and IV) would need more area or special designs. Thus, the LTAR range 0.8–0.6 gpd/ft2 maps to Soil Group II.

Long-term infiltration rate (LTAR) shows how much wastewater a soil can accept per square foot over time, guiding the size of the drain field. A range of 0.8 to 0.6 gpd/ft2 sits right in the middle of the spectrum, indicating a moderate infiltration capacity. That mid-range is designated as Soil Group II, which has neither the high permeability of the best soils nor the low permeability of the poorest soils. Soils with higher LTAR (Group I) would allow more flow per area and generally require less drain-field area, while soils with lower LTAR (Groups III and IV) would need more area or special designs. Thus, the LTAR range 0.8–0.6 gpd/ft2 maps to Soil Group II.

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