Laserfiche WebLink
I <br /> 11-4 MULTIPASS (RECIRCULATING) PACKED-BED FILTERS 741 <br /> Recirculating Effluent <br /> gravel filter sampling <br /> location <br /> UV disinfection <br /> Effluent <br /> pump Dosing <br /> station tank <br /> Septic <br /> tank <br /> effluent <br /> Recirculation UV <br /> + x: <br /> tank recirculation <br /> tank Isolation <br />' valve <br /> Subsurface drip <br /> Q .Pump in tank irrigation system <br /> Float valve in tank Community ' <br /> drainfield <br /> FIGURE 11-20 <br /> Schematic of Stonehurst treatment system incorporating recirculating fine gravel filters. <br /> (see Fig. 11-21), a UV (ultraviolet light) disinfection unit, a subsurface drip irriga- <br /> tionsystem for reuse of treated effluent, and a community leachfield for wintertime !, <br /> i disposal, when needed. The disinfected wastewater is required to have a 30-day av- <br /> erage BOD and TSS of 15 mg/L, settleable solids concentration of 0.1 mL/L, and a ., . <br /> total coliform concentration equal to or less than 23 MPN/100 mL. <br /> r v <br /> �� <br /> I! <br /> ,(i(in rr''�y�i�'�.f ta�Y'3=�s,;'tq�y-..s•.��`3,� :C �I - �f ' -��,�- +.�� -R ' <br /> . 3 <br /> FIGURE 11-21 <br /> View of recirculating gravel filter for Stonehurst development <br /> near Martinez, California. Building in background houses <br /> the UV disinfection system. <br /> k <br /> E <br />