A Illustrations and Exhibits

Section 905.APPENDIX A   Illustrations and Exhibits Section 905.ILLUSTRATION H   Subsurface Seepage System Size Determination Section 905.EXHIBIT A   Gravel System Time (minutes) required for last 6 inches of water to fall FOR RESIDENTIAL USE Required Absorption Area (sq ft)/bedroom) FOR INSTITUTIONAL OR COMMERCIAL USE Allowable application rate (GPD/sq ft) (5) Recommended depth from bottom of the trench to the limiting layer 18 - 60 200 1.0 90 210 .95 3 feet 120 235 .85 150 265 .75 180 290 .69 240 320 .62 300 350 .57 2 feet 360 385 .52 NOTE: 1. Absorption area is figured as trench bottom area in absorption trenches and bottom area in seepage beds. 2. Seepage beds require 1½ times the seepage field absorption area specified. 3. Over 360 is unsuitable for subsurface seepage systems. 4. Under 18 is unsuitable for subsurface seepage systems. 5. Divide the required total gallons per day by this number to get the number of square feet required