|
Effective April 28, 2015 Chapter Four Subsurface Sewage Treatment System Regulations
<br />(B) The distribution system or media must not place a hydraulic head greater than 30 inches
<br />above the bottom of the absorption area.
<br />(4) The system's absorption area must be in original soil.
<br />(5) The system's absorption area and mound absorption ratio must be sized according to the Table VI
<br />Loading Rate for Determining Bottom Absorption Area and Absorption Ratios Using Detailed Soil
<br />Descriptions, or by using Table Vla if not using detailed soil descriptions. Soils with a loading rate
<br />less than 0.45 gallons per day per square foot cannot be used in a Type I or Type II system for new
<br />construction.
<br />Table VI
<br />Loading Rates for Determining Bottom Absorption Area and Absorption Ratios Using Detailed Soil
<br />Descriptions*.
<br />Treatment Level
<br />Treatment Level C
<br />Treatment Levels
<br />Treatment Levels A,
<br />C
<br />A, A-2, B, and B-2
<br />A-2, B, and B-2
<br />Soil Structure and
<br />Absorption Area
<br />Mound Absorption
<br />Absorption Area
<br />Mound Absorption
<br />USDA Soil Texture
<br />Grade
<br />Loading Rate
<br />Ratio
<br />Loading Rate
<br />Ratio***
<br />(gpd/ftz)
<br />(gpd/ftz)
<br />Sand, coarse sand,
<br />loamy sand, loamy
<br />Single grain,
<br />coarse sand, fine sand,
<br />granular, blocky, or
<br />very fine sand, loamy
<br />**
<br />1.0
<br />**
<br />1.0
<br />fine sand, loamy very
<br />Prismatic structure;
<br />fine sand, 35-50% rock
<br />Weak grade
<br />fragments
<br />Sand, coarse sand,
<br />Single grain,
<br />loamy sand, loamy
<br />granular, blocky, or
<br />coarse sand, <35% rock
<br />prismatic structure;
<br />1.2
<br />1.0
<br />1.6
<br />1.0
<br />fragments
<br />weak grade
<br />Fine sand, very fine
<br />Single grain,
<br />sand, loamy fine sand,
<br />granular, blocky, or
<br />loamy very fine sand,
<br />prismatic structure;
<br />0.6
<br />2.0
<br />1.0
<br />1.6
<br />>35% rock fragments
<br />weak grade
<br />Sandy loam, coarse
<br />Granular, blocky, or
<br />sandy loam, fine sandy
<br />Prismatic structure;
<br />0.78
<br />1.5
<br />1.0
<br />1.6
<br />loam, very fine sandy
<br />weak to strong grade
<br />loam
<br />Sandy loam, coarse
<br />sandy loam, fine sandy
<br />Platy with weak
<br />loam, very fine sandy
<br />grade or massive
<br />0.68
<br />1.8
<br />0.87
<br />1.8
<br />loam
<br />Granular, blocky, or
<br />Loam
<br />prismatic structure;
<br />0.6
<br />2.0
<br />0.78
<br />2.1
<br />weak to strong grade
<br />Platy with weak
<br />Loam
<br />grade or massive
<br />0.52
<br />2.3
<br />0.68
<br />2.4
<br />Granular, blocky, or
<br />Silt loam, silt
<br />prismatic structure;
<br />0.5
<br />2.4
<br />0.78
<br />2.1
<br />weak to strong grade
<br />Silt loam, silt
<br />Platy with weak
<br />0.42
<br />2.9
<br />0.65
<br />2.5
<br />grade or massive
<br />Granular, blocky, or
<br />Clay loam, sandy clay
<br />prismatic structure;
<br />0.45
<br />2.6
<br />0.6
<br />2.7
<br />loam, silty clay loam
<br />moderate to strong
<br />grade
<br />62 Washington County Development Code
<br />
|