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Each lateral is to have 1/8" orifices spaced every 3 ft, for a total of 64. Each orifice will have orifice shields place over them. As illustrated on the attached aerial photo (§7.1.1, §7.1.4), the effluent is to discharge to a 32 ft E-W x 28 ft N-S= 896 sf filter bed. (EHD required leachline= 300 LFLL x 3 (Based on perc rate obtained) = 900 sf. The 100%reserve area is also noted. These referenced disposal areas may be switched depending on the influent tightline location. The filter bed (§9.4) will have a minimum of 12" of drain rock below the laterals and at least 2" of drain rock extending above the laterals. Filter fabric is to be laid over the drain rock and a minimum of 6" native excavated soil cover backfilled to surrounding grade. The Attachments to this Report include the following: 1. Aerial Photo illustrating Modular Home anticipated footprint, Primary/Reserve Filter Bed, Distance from existing leachfield and adjacent well (§7.1.1). 2. MVP-DAX DM Setting Instructions for time dosing. Time dosing factory defaults are listed on Page 1 of 3. 3. Splice Boxes 4. Float Switch Assemblies 5. PF Series 4" Submersible Effluent Pumps 6. High Head H =V (W/ Check Valve) 7. Universal Biotube Pump Vault CONCLUSIONS AND RECOMMENDATIONS The shallow subsurface soils underlying the subject property where the new filter bed disposal area is to be installed, reveals a silty sand soil structure with rapid permeability at the three ft depth and slower permeability at the 10 ft depth. Sufficient area exists for the 100% replacement area, as detailed on the aerial photo. The Operations and Maintenance Plan(§1.12.1) for this system includes periodic cleaning of the screened area of the Biotube, bottle brush cleaning of the discharge piping, and opening lateral distal valves to discharge biological growth. The application rate was determined from the perc rate to be 0.800 gallons/ft2/day. The total filter bed area is 896 ft2 of floor area. Therefore, the filter bed can readily manage: 0.800 gallons/ft2/day x 896 ft2 = 717 gpd (§7.1.3). The Average Daily Flow(ADF) as determined by Terracon for the proposed second unit dwelling was 200 gpd. Therefore, the filter bed design is more than ample in area. It is recommended that the kitchen sink should not have a disposal. All food waste should be handled as solid waste and disposed of in the garbage. All onsite wastewater treatment systems (septic systems) will eventually fail. A reasonably long lifespan of the disposal area can be expected based on the perc rates obtained and the design factors.. Page -2- Chesney Consulting