Changes

This method of determining [[design infiltration rate]] is only approved for native Clean Sand and Dune Sand (SP) with d₁₀ between 0.1 - 2.5 mm (i.e. soils to which the Hazen formula is applicable). This method is not allowed within areas of fill.

This method of determining [[design infiltration rate]] is only approved for native Clean Sand and Dune Sand (SP) with d₁₀ between 0.1 - 2.5 mm (i.e. soils to which the Hazen formula is applicable). This method is not allowed within areas of fill.

==Procedure== 

 

==Procedure==

 

# Collect [[soil]] samples for each defined soil layer below the bottom of the proposed infiltration facility. Layers must be evaluated to the following depths, depending upon facility type:

# Collect [[soil]] samples for each defined soil layer below the bottom of the proposed infiltration facility. Layers must be evaluated to the following depths, depending upon facility type:

## For [[bioretention]] facilities, analyze each defined layer below the proposed facility bottom to a depth of at least 3 times the maximum ponding depth, but not less than 1 m.  

## For [[bioretention]] facilities, analyze each defined layer below the proposed facility bottom to a depth of at least 3 times the maximum ponding depth, but not less than 1 m.