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HomeMy WebLinkAbout1989-06-02 Septic System Design ReportY-7a - L/3o0 sys'rEM DESIGN POR THE VARS RESIDENCE 7 _) N . FERNDAL E ROAf7 URC)NO, MINNESO TA 6-2-89 JUN Enclosed are the results from the percolation testing and soil borings taken on the above property as well as system design in- formation for a pressure mound system. All construction and materials must adhere to the provisions of the City of Orono. In addition to the enclosed requirements, two septic tanks of at least 1000 gallons will be needed if the pre- sent tanks do not meet current standards. Also, a pumpinq tank of at ](-ast 750 gallons is rQcommended to house the required pump. An alarm device should be used to warn of pump failure. If different pumping lengths or heights area used than shown in the design, those changes must be taken into account. Drainage from runoff must be diverted away from the mound system. If any other information is needed, please contact me. Sincerely, PERCOR, INC. -.go M Gronbe r A�g, PCA certified r�Jvly I 4eyt-111, l VA IC T A'e riU E N C E' S 73' ". FF.4'A✓OA t E RD. 0ROAv0 . 74iAA,1EJarA I 1 /Y« WMNf r � • SrB- -70 NtooT MIk f C o PSI r,a,v /Vaal VA K.S E-19 MOUND DESIGN PROCEDURE. (For Flows up to 1200 gpd) A. Sewage Flow Rate See D-7 or I-3, 4, or 5, or use metered value; Flow Rate = C gpd B. Septic Tank Liquid Volume (see C-3 or C-5) ��_. , gallons C. Soil Characteristics 1. Depth to restricting layer such as seasonally saturated soil, bedrock, coarse soil, etc.; ,!-inches 2. Depth of percolation tests; / $ inches 3. Number of percolation test holes; 3 holcq 4. Ave. percolation rat- L12, Y '-,Pi 5. Landslope = 7 D. Rock Layer Dimensions 1. Multiply gpd by 0.83 to obtain required area of rock layer; K' gpd x 0.83 sq ft 2. Select width of rock layer (10 feet or less) - /O feet 3. Length of rock layer a Area - Width sq f t , p ft ft E. Rock Volume 1. `lultiply rock area by rock depth to get cubic feet of rock; Saa sq ft x / ft iSO0cu ft 2. Divide cu ft by 27 cu ft/cu yd to get cubic yards; /.9. _,- 3. !Iultiply cubic yards by 1.4 to get weight of -ock in tons; /'.','.'cu yds x 1 .4 a 1v ' tons F. Pressure Distribution System 1. Select number of perforated laterals 6 2. Select perforation spacing .3 ft 3. Select perforated lateral length; Note if manifold is at end of rock layer, lateral length is rock layer length less half a perforation spacing. If ,manifold is in center of rock layer, lateral length is one-half rock layer length less half a perforation spacing. Perforated lateral length - 2T. S ft. 4. Divide lateral length by perfor- ation spacing to get number of perforations per lateral !2, 5 feet 3_feet �_perfs Note: last perforation must be in end cap, (see page E-14) 5. Multiply perforations per lateral by number of laterals to ;;et total 'number of perforations; yperf s/lat x _(�lats 6. Determine required flow rate by multiplying number of perforations by flow per %Y PfK:=i. perforation (see page E-17) J , perfs x.71/gpm/perf -.l 5gpm 7. Select minimum required lateral diameter from table on Page E-17; enter table with perforation spacing, perforation diameter, and number of perforations per lateral. Select minimum diameter for perforated lateral / %/ " inches ".re I %2 " G. Basal Width 1. Percolation rate in top 12 inches of soil is ?2,�mpi 2. Select allowable coil loading rate from table on page E-16; 4ef O. SO gpd/f t- �� hFi>�c:c9/ji E-20 MO= DESIGN PROCEDURE (ContiL •red) (For Flows up to 1200 gpd) G.3. Cal=ulate basal width ratio by dividing rock laver loading rate of 1.20 gpd/ft2 by allowable soil loading rate; 1.20 gpd/ ft2=O.SOgpolft2 = L" YO Check this value on page E-16. 4. Multiply basal width ratio by rock layer width to get required basal width; j.yo x /C ft-2Y.Oft H. Downslope Dike Width 1. If landslope is 31 or more:, subtract rock layer width from basal width to obtain minimum downslope dike toe width ZdE.7 ft - ' % ft -AC 7 f t 2. Calculate mound height at edge of rock layer on downslope side; a. Deteraine depth of clean sand fill at upslope edge of rock layer: /.O feet b. Multiply rock laver width by landslope to determine drop it: elevation; x %100 =✓.7ft c. Add drop in elevation to depth of clean sand at upslope edge of rock layer to get depth of clean sand at downslope edge of rock 1.,.er. 7ft + ,eft 7 ft d. Add depth of clean sand at down - slope edge to depth of rock laver to depth of soil backfill to get mound height at downslope edge of rock layer; /._7ft +.'. ft + /. ' ft 7 f t e. hinter table on page E-18 with landslope and downslope dike ratio. Select dike multiplier of 5. `✓lS Y. I1.2.f. Multiply dike multiplier by downslope mound height to get downslope dike width; S,S6xZ.Z= 06ft g. Compare the values of step H.1 and step H.2.f. Select the greater of the two values as the downslope dike width; ZY. D feet h. Calculate upslope dike width using upslope mound height and upslope dike multiplier rom page E-18; 9, y f t X X, 0 - i. Total mound width ib the sum of upslope dike width plus rock layer width plus downslope dike width; c%, /ft + /4; ft + Vft-VJ.yft 3. If landslope is 2.9 percent or less, basal width includes both the upslope and downslope dike widths. a. Calculate downslope dike width using steps H.2.a..through H.2.f; feet b. Calculate upslope dike width u:;ing upslope mound height and dike multiplier from Page F.-18; x ft = ft Add downslope dike width to upslope dike width to ruck Layer width to get total mound width; `ft + - _ft + _ft = _ft d. Compare total mound width to required basal width from step G.4. If total mound width is greater than required basal widt:i, use calculated dike widths. If required basal width is greater than total mound width, increase downslope dike width. YAWS r?� :'. F-15 PUMP SELECTIL" PROCEDURE A. Determine pump capacity: 1. Minimum suggested is 600 gallons per hour (10 gpm) - to stay ahead of water use rate 2. Maximum suggested for delivery to a drop box of a home system is 2700 gallons per hour (45 qpm) to prevent buildup of pressure in drop box 3. Use value from design of pressure distribution system SELECTED PUMP CAPACITY . . . . .. . . . . . . . . . . . fir- S Rpm , B. Determine head requirements: 1. Llevation difference between pump and point of discharge _ feet 2. If pt-rping to a pressure distribution system. add 5 feet for pressure required at manifold . . . . . . . . . . S feet 3. Friction loss a. Enter friction loss table with gpm and pipe diameter. Read friction loss in feet per 100 feet from page F-18. F. L. = i, / ft/100 ft b. Determine total pipe length from pump to discharge point. Add 25 percent to pipe length for fitting loss, or use a fitting lotin chart. Equivalent pipe 2�� feet lrnl"lII - .."I t t^It... I•il)r Ionr0i - 1 35 :: �U�O' _._ C. Calculatt• tt,tal it•it•tioll ltl;:,: by unlltiplyin1; frictiun IOSS In ft/100 ft by equivalent pine Ivilgth . Total friction loss %_/i -.x 7G0 • feet t. _ Total head rt•nttired i,: the sum of elevation difference, special head r.quirements, and total friction loss. + S +_Zy. J— TOTAL HEAD . . . . . . . . . . . . . . . . . . . . . . 17, 3 feet C. Pump selection 1. A pump must be selecte to deliver at least gpm with at least _ 2*;*. 3 feet of total head. D. To maximize pump life select sump size for 4 to 5 pump operations per day. I'. CalcuLate drainback L. Determine total pipe length, /6l) feet. 2. Determine liquid volume of pipe. gallons per 100 feet. (See page E-18) 3. Mult:ynl}• length by volume: Drainback quantity fee:: x /J, S,.. gallons/100 ft 16', ? gallons Suggested drainback quauti.y is 10 percent of pumped quantity. A larger drainback percentage will decrease pump station efficiency slightly but pumping energy costs are usually a relatively small parr of the total household energy costs. U-39 PEItCOLA'TION TEST DATA SHEET Test hole location_ V /.ik hole number Date test hole was prepared j-- rc — r''/ , Depth of hole bottor:,_L�? inches. Diameter of tole, I inches. Soil data from test hole: Depth, inches Soil texture C) O L '4 k L. "4" I,ethod of scratching sideaall _ 'Lai `i �0' Depth of pea -sized gravel in bottom of hole, '1., inches. Date and hour of initial crater filling % 1 Depth of initial water filling, inches above hole botto^. Metbid used to maintain at least 12 inches of Water depth in hole for at least 4 hours /! /I, L- L Percolation test readings made by I)- 'rI:•,- I •• r + �•.. f r a.m. •• •- 'l starting at � � - . (date) rI �. during test, `/„ inches. on Maxirnum water depth above hole bottom Time Time Irterval, :'mutes :Ssasurement, inches Drop in water level, inches Percolation rate, minutes per inch ?remarks J !+� -7 )J /;' Percolation rate e 31.1 minutes inch. $-39 PERCOLATION TEST DATA SHEET Test hole location Hole number Date test hole was prepared Depth of hole bottom, _l e inches. Diameter of hole, _g�_ inches. Soil data from test hole: Depth, inches Soil texture _ Log r,& L ^� Method of scratching, sidewall Depth of pea -sized gravel in bottom of ho1u, inches. Date and hour of initial water filling '- A `t -- y- Y.;L 14+ �. Depth of initial water filling, Lr inches above hole bottom. Method used to maintain at least 12 inches of water depth in hole for at least 4 hours LL Percolation test readings made by �!� �' " i" .� f ;%': on .� a.m. th above hole bottom 5 _ % 4- '! starting at '1 . / Maximum water de p (date) during test, 3 s inches. Time Ti=e Interval, Minutes '.`.easurement, inches Percolation Drop in water rate, Remarks level, inches minutes per inch / :. i 7 - / minutes per inch. Percolation rate /''.� B-39 PERCOLATION TEST DATA SHEET Test hole location L11 Hole number j Date test hole was prepared f Depth of hole bottom,-L-e— inches. Diameter of hole, �— inches. Soil data from test hole: Depth, inches �rJ Soil texture D - l ' L Ai/Cv� tiAd Method of scratching sideaall i, } /P Depth of Dea-sized gravel in bottom of hole, inches. Date and hour of initial .cater A /1. Depth of initial water filling, inches above hole bottom. Method used to maintain at least 12 inches of water depth in hole for at least 4 hours Percolation test readings made by on starting at f i ' a.m. Maximum water depth above hole bottom (date) �. during test, ,s 3 ` inches. Time Time Interval, Minutes Measurement, inches Drop in water level, inches Percolation rate, minutes per inch Remarks c / / I n •, ?0 ?' r, ! L! i `::� r•�j I ' f�►sLx Percolation rate i minutes per inch. B-zl- Location or Project Borings made by %� �j/r/' f: /+��! . �; �)!"�'f Date �� 1b — 1� Classification System: AASHO ; USDA-SCS _�K ; Unified other _ Auger used (check two): Band �( , or Power ; Flight , or Bucket X-; other Depth, Boring number in Surface elevaticn feet 0 -T/ W cr 1 . L iAl 3 — --• End of boring at ? feet. Standing water table: Present at feet of depth, hours after boring. Not present in boring hole '.Mottled soil: Observed at •feet of depth. Not present in boring, tilde Obs�.: vations :Ind Depth, Boring number in feet Surface elevation 0 G1r jt — Dz/vE L j 4y 3 ---- 1r*411 6,''Ay -Zip% CV L o A� 4 — ,; S — 6 -- 7 — 8 — End of boring at feet. Standing water table: Present at feet of depth, hours after boring. Not present in boring hole rinttled soil: Observed at _i ��feet of depth. Not present in borintt hole Observations and co-. ..nts: - Heavy Duty Submersible Sewage and Effluent Pump Pump Specificatic ,,.s Size: 2" Discharge, 1Y." Suct on Opening Impeller. 2 Vanes, Molded Material with Pressure Vanes on back -_vJe Seal: Mechanical Type with Cr:ramic and Carbon Faces Pump Body: Cast Iron Motor Housing: Cast Iron Hardware: Corrosion Flesista•,+ Stainless Steel Power Cord: 15' of 14/3 SJTC� Suitable For. 1500 Liquids Standard Equipment: Equippr• 1 with Legs for 1',:" setting above bot: n of Sump Basin 4 E 1 11 2112 Models SE411 SE421 Size 2„ Handles 1-1/2" Solids NOTE: Pump can operate dry for extended periods without damage to motor and/or seals. peabodyBaRnes Motor Specifications Model SE411 - 4/10 HP, 115 Volt, Single Phase Model SE421 - 4/10 HP, 230 Volt, Single Phase Single Phase: F'SC (Permanent Split Capacitor) Completely Oil -Filled and Overload Protection In Motor Motor Speed: 1:00 R.P.M. Shaft: 1/2" Diameter 416 Stainless Steel Thrust Bearing: Ball Radial Bearing: Sleeve - Permanent Lubrication M Models SE411 SE421 8. Peabody BaRnes 651 North Main Street. Mansbe'd Oh,o •1 VY)2 Phone 419,1522.1511 00 NPT ISCHARGE 0 1.56 1./9 UTA. SUCTION AMPERAGE Max. Lockets Model Run Roby No. Amps Amps SE411 9.0 15.5 SE421 4.5 7.8 MA09 m LL—T,.�© MoMmUsp FS a ImpUlluffi: as ■■■■■■■■■ wi•■■■■■l ■■■■■■ ■■ ■■ ■■ ■ ■ • \■ me ■■.ram-- ■■HIMUOth �f■f■�■rr��.• • ■ ■ f■ ■ ■■■■■ ■■■E f=l =i:■\�\ on ■■s■ •■� ��_!1:11:11i; eiaiiiieei ■■■u ......�.�-on lipm Mason "ME a ME Mm.vw - 0