[an error occurred while processing this directive]

PRODUCT INFORMATION SHEETS

Product:	FB300 -- Sand filter containment for 300 gpd system
System design recirculation ratio of 2:1 is accomplished by installing 6 spray 
heads in recirculation side of filter and 3 spray heads in effluent side
Tank sides are tapered, so hydraulic loading rate is calculated on basis of 
dimensions at 6" below top of filter media, approximately 26" from tank bottom.
	2" taper in 48" ==> 0.0417"/inch of depth ==> 1.08" at 26" depth
Recirculation side plan dimensions:
	(60"+2x1.08") x (58"+2x1.08") = 62.16" x 60.16" = 25.97 ft2 surface area
Effluent side plan dimensions:
	(42"+2x1.08") x (58"+2x1.08") = 44.16" x 60.16" = 18.45 ft2 surface area
Forward flow loading onto recirculation side is 2/3 x 300 = 200 gpd
Forward flow loading onto effluent side is 1/3 x 300 = 100 gpd
Recirculation side hydraulic loading rate:	200/25.97 = 7.7 gal/ft2/day
Effluent side hydraulic loading rate:	100/18.45 = 5.4 gal/ft2/day

Product:	FB450 -- Sand filter containment for 450 gpd system
System design recirculation ratio of 2:1 is accomplished by installing 8 spray 
heads in recirculation side of filter and 4 spray heads in effluent side
Tank sides are tapered, so hydraulic loading rate is calculated on basis of 
dimensions at 6" below top of filter media, approximately 26" from tank bottom.
	2" taper in 60" (wall height is 48", but taper is set by form used)
		==> 0.0333"/inch of depth ==> 0.87" at 26" depth
Recirculation side plan dimensions:
	(80"+2x0.87") x (68"+2x0.87") = 81.74" x 69.74" = 39.59 ft2 surface area
Effluent side plan dimensions:
	(54"+2x0.87") x (68"+2x0.87") = 55.74" x 69.74" = 27.00 ft2 surface area
Forward flow loading onto recirculation side is 2/3 x 450 = 300 gpd
Forward flow loading onto effluent side is 1/3 x 450 = 150 gpd
Recirculation side hydraulic loading rate:	300/39.59 = 7.6 gal/ft2/day
Effluent side hydraulic loading rate:	150/27.00 = 5.5 gal/ft2/day

Product:	SP300 -- Septic/pump tank for 300 gpd system
Performance criteria:
	Septic tank HRT = 3.75 days = 3.75 x 300 = 1,125 gallons
	Emergency (pump failure) storage = design gpd = 300 gallons
	Dosing tank equalization volume = 80% x design gpd = 240 gallons
All tank walls taper 2" over 60" wall height ==> 0.0333"/inch of depth
Septic tank volume:
	Bottom area:  96" x 68" = 45.33 ft2
	Overflow depth = 45" = 3.75 ft ==> taper = 45x0.0333 = 1.50"
	Top area:  (96+2x1.50") x (68"+2x1.50") = 99" x 71" = 48.81 ft2
	Average area = (45.33+48.81)/2 = 47.07 ft2
	Volume = 47.07 ft2 x 3.75 ft = 176.51 ft3 = 1,320 gallons -- OK
Dosing tank:
	Chamber bottom dimensions:  42" x 68"
	Permanent ponding depth (bypass valve opens) = 10" ==> taper = 0.33"
	Area at 10" depth:  (42"+2x0.33")x(68"+2x0.33") = 42.66"x68.66" = 
       20.34 ft2
	Neglecting taper, depth required for equalization volume:
		240 gal/7.481 = 32.08 ft3/20.34 ft2 = 1.58 ft = 19"
		==> top of equalization volume is at 10" + 19" = 29" -- set at 30"
		    At this depth, taper = 30 x 0.0333" = 1.00"
	Area at 30" depth:  (42+2x1.00")x(68+2x1.00") = 44"x 70" = 21.39 ft2
	Actual equalization volume provided:
		Average area = (20.34+21.39)/2 = 20.87 ft2
		Volume = 20.87 ft2 x (30-10)/12 ft = 34.78 ft3 = 260 gallons -- OK
	Emergency storage:
		Storage begins at alarm level = top of equalization = 30" depth
		Area at 45" septic tank overflow depth (taper = 1.50"):
			(42+2x1.50")x(68+2x1.50") = 45" x 71" = 22.19 ft2
		Average area between 30" and 45" = (21.39+22.19)/2 = 21.79 ft2
		Volume = 21.79 ft2 x (45-30)/12 ft = 27.24 ft3 = 204 gallons
		Remaining volume required = 300 - 204 = 96 gallons
		Total area in septic tank and dosing tank at 45" depth
			= 48.81 + 22.19 = 71.00 ft2
		Neglecting taper depth required to obtain 96 gallons volume:
			96 gal/7.481 = 12.83 ft3/71.00 ft2 = 0.18 ft = 2.2"
		==> Required storage volume obtained at 2.2" above bottom of entry
           port = 47.2" total depth -- OK
Effluent tank:
Emergency storage restricted to 54" maximum depth to assure no overflow into 
dosing chamber  ==> taper = 54 x 0.0333 = 1.80"
	Area at 54" depth:  (42"+2x1.80")x(68"+2x1.80") = 45.60"x71.60" 
       = 22.67 ft2
	Neglect taper for first approximation of emergency storage depth:
		300 gal/7.481 = 40.10 ft3/22.67 ft2 = 1.77 ft = 21.2"
	Taking taper into account, try 23" storage depth
		==> bottom of storage at 54" - 23" = 31" ==> taper = 31x0.0333 
       = 1.03"
	Area at 31" depth:  (42"+2x1.03")x(68"+2x1.03") = 44.06"x70.06" = 21.44 ft2
	Average area = (21.44+22.67)/2 = 22.06 ft2
	Volume = 22.06 ft2 x 23/12 ft = 42.28 ft3 = 316 gallons -- OK
Volume below 31" depth is available for dose depth, permanent ponding depth 
and lag between top of dose and alarm
	Permanent ponding depth for pump cooling = 12" ==> taper = 0.40"
	Area at 12" depth:  (42"+2x0.40")x(68"+2x0.40") = 42.80"x68.80" = 20.45 ft2
	Allow 1" lag between top of dose and alarm
		==> top of dose at 30" ==> taper = 30 x 0.0333" = 1.00"
	Area at 30" depth:  (42"+2x1.00")x(68"+2x1.00") = 44" x 70" = 21.39 ft2
	Average area = (20.45+21.39)/2 = 20.92 ft2
	Volume = 20.92 ft2 x (30-12)/12 ft = 31.38 ft3 = 235 gallons
	Typical dose volume required for single zone modified at-grade LPD field
		= approx. 1/3 of daily design flow = 100 gallons
	==> Volume available in effluent tank is sufficient

Product:	SP450 -- Septic/pump tank for 450 gpd system
Performance criteria:
	Septic tank HRT = 3.75 days = 3.75 x 450 = 1,688 gallons
	Emergency (pump failure) storage = design gpd = 450 gallons
	Dosing tank equalization volume = 80% x design gpd = 360 gallons
All tank walls taper 2" over 60" wall height ==> 0.0333"/inch of depth
Septic tank chamber volume (in SP450):
	Bottom area:  54" x 68" = 25.50 ft2
	Overflow depth = 45" = 3.75 ft ==> taper = 45x0.0333 = 1.50"
	Top area:  (54+2x1.50") x (68"+2x1.50") = 57" x 71" = 28.10 ft2
	Average area = (25.50+28.10)/2 = 26.80 ft2
	Volume = 26.80 ft2 x 3.75 ft = 100.50 ft3 = 752 gallons
	Primary septic tank = 1,000 gallons + 752 gallons = 1,752 gallons -- OK
Dosing tank:
	Chamber bottom dimensions:  60" x 68"
	Permanent ponding depth (bypass valve opens) = 10" ==> taper = 0.33"
	Area at 10" depth:  (60"+2x0.33")x(68"+2x0.33") = 60.66"x68.66" = 28.92 ft2
	Neglecting taper, depth required for equalization volume:
		360 gal/7.481 = 48.12 ft3/28.92 ft2 = 1.66 ft = 20"
		==> top of equalization volume is at 10" + 20" = 30" -- set at 32"
		    At this depth, taper = 32 x 0.0333" = 1.07"
	Area at 33" depth:  (60+2x1.07")x(68+2x1.07") = 62.14"x 70.14" = 30.27 ft2
	Actual equalization volume provided:
		Average area = (28.92+30.27)/2 = 29.60 ft2
		Volume = 29.60 ft2 x (32-10)/12 ft = 54.27 ft3 = 406 gallons -- OK
	Emergency storage:
		Storage begins at alarm level = top of equalization = 32" depth
		Area at 45" septic tank overflow depth (taper = 1.50"):
			(60+2x1.50")x(68+2x1.50") = 63" x 71" = 31.06 ft2
		Average area between 32" and 45" = (30.27+31.06)/2 = 30.67 ft2
		Volume = 30.67 ft2 x (45-32)/12 ft = 33.23 ft3 = 249 gallons
		Remaining volume required = 450 - 249 = 201 gallons
		Total area in septic tank and dosing tank at 45" depth
			= 28.10 + 31.06 = 59.16 ft2
		Neglecting taper depth required to obtain 201 gallons volume:
			201 gal/7.481 = 26.87 ft3/59.16 ft2 = 0.45 ft = 5.5"
		==> Required storage volume obtained at 5.5" above bottom of entry
            port = 50.5" total depth -- OK
Effluent tank:
Emergency storage restricted to 54" maximum depth to assure no overflow into 
dosing chamber  ==> taper = 54 x 0.0333 = 1.80"
	Area at 54" depth:  (48"+2x1.80")x(68"+2x1.80") = 51.60"x71.60" = 25.66 ft2
	Neglect taper for first approximation of emergency storage depth:
		450 gal/7.481 = 60.15 ft3/25.66 ft2 = 2.34 ft = 28.1"
	Taking taper into account, try 30" storage depth
		==> bottom of storage at 54" - 30" = 24" ==> taper = 24x0.0333 = 0.80"
	Area at 24" depth:  (48"+2x0.80")x(68"+2x0.80") = 49.60"x69.60" = 23.97 ft2
	Average area = (23.97+25.66)/2 = 24.82 ft2
	Volume = 24.82 ft2 x 30/12 ft = 62.05 ft3 = 464 gallons -- OK
Volume below 24" depth is available for dose depth, permanent ponding depth 
and lag between top of dose and alarm
	Permanent ponding depth for pump cooling = 12" ==> taper = 0.40"
	Area at 12" depth:  (48"+2x0.40")x(68"+2x0.40") = 48.80"x68.80" = 23.32 ft2
	Allow 1" lag between top of dose and alarm
		==> top of dose at 23" ==> taper = 23 x 0.0333" = 0.77"
	Area at 23" depth:  (48"+2x0.77")x(68"+2x0.77") = 49.54"x69.54" = 23.92 ft2
	Average area = (23.32+23.92)/2 = 23.62 ft2
	Volume = 23.62 ft2 x (23-12)/12 ft = 21.65 ft3 = 162 gallons
	Typical dose volume required for single zone modified at-grade LPD field
		= approx. 1/3 of daily design flow = 150 gallons
	==> Volume available in effluent tank is sufficient

Click here to return to the previous page.