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There is ample 100% reserve/replacement area that can be either directly west of the primary disposal area, or installed in the almond orchard after a determined number of almond trees are removed, as can be seen on the aerial photo. B. FILTER BED/SEEPAGE PIT SIZING CALCULATIONS The filter bed disposal area will be located directly northwest of the proposed Facility, as noted on the Site Plan. The Site Plan only illustrates three leachlines since the disposal area/configuration was unknown at the time of drafting. Based upon the information contained in this report, a filter bed, with three adjoining seepage pits is proposed as the construction configuration. The seepage pits are recommended due to the aforementioned repairs and percolation test failing rates. Although the Facility could be deemed residential, for disposal area determinations, it is commercial. Therefore, commercial calculation requirements will be used: The average daily flow (ADF) = 70 gals/person/day x 2 people = 140 gpd x 3 bedrooms = 420 gpd. 1,200 Base Tank Capacity (BTC) + 420 gpd = 1,620 1,620 x 0.200 (LL Soil Factor -sandy loam) = 324 Lineal Feet of Leachline (LFLL) 324 x 4 (Filter Bed Soil Factor) = 1,296 sf Filter Bed. Note: A Soil Factor of 4 (not 3) was used due to failing perc rates at the 36" perc test depth. Three 36" dia. seepage pits are proposed at the distal end of the filter bed and connected to the filter bed in the same fashion as connection of a seepage pit to a leachline trench. V. CONCLUSIONS AND RECOMMENDATIONS NLS§ 4.1. The nitrate loading calculations show the effluent from the proposed Assisted Living Facility will theoretically possess a nitrate -nitrogen concentration of 0.4 mg/L NO3-N, after the effluent percolates through the receiving soils. The characteristics of the receiving soils indicate significant denitrification capabilities. From the physical and chemical test results of this soil, no one soil characteristic of the underlying soils can be referenced exhibiting properties that promote this degree of denitrification. Although these nitrogen tests were conducted on soil particles and not vadose zone water, test results still reveal a dramatic decrease in nitrogen concentrations with increasing depth. Considering that water use in the Facility may be significant, three seepage pits are proposed to be installed at the distal end of the filter bed. The effluent disposal structures can theoretically manage: 1,296 sf (FB) + 585 sf (3-36" Pits) = 1,881 sf x 0.371 gals/sf/day (Avg. Application Rate) = 700 gpd Consideration should be given to using biodegradable toilet paper since it is anticipated that paper use may be significant. There are many brands on the market; Scotts® Rapid -Dissolving Toilet Paper is an example. Popular wipes that are on the market should be avoided since they do not decompose in the septic tank environment. Page -7- Chesney Consulting