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HomeMy WebLinkAbout1992-07-30 Septic System Design Specifications Pg1nOUND SYSTEM DES1UN'1JA1'A A Sewega Flow Hate (based on Table It Minnesota /R_.'ules, Part 7080) Type House _ 13R _4le � 0 gpd i3 Septic 'ranK Volume ODD' v�'1. ","oo Ai2o U Soil Charsteristics: 1 Depth to high seasonal zone of saturation level Mottled soil level 23 inches 2 Average rercolation Rate �o � G. :� min/inch Design range 3l 41S min/inch� 3 Soil sizing factor 0,93 3 sq. ft./ gpd It Laud Slope 62 c% % D RocK ia;+er k Treatment Area) Dimension 1 A150 gals/day X O03 sq ft / gal 3 sq. ft. of treatment area + 1u_ O sq. ft. 2 _ % O ft. wide X ft. long 3 Hock Volume needed: 4410 sq. ft. treatment area X NVQ ft. depth of rock • i t cu. yds. X 1 a • I Ton +) od)U is Overall Dimensions of Mound: Wp,� 9, iC� 1't. wide .3' e. ,..rta•d �• �_ i't. xock width __ ft. �sy _y �r i't. .long Hock length % / ft. End Slope Lengtn % ft. 3 total Lawn area ��_ i't. X�C` ft. c� p. ft. 5-'1112-1 0 Amount of nateria.l kededl 1 Sand t Int thick) U U cu. yds.. `�u v,n.-1 , C1.'lG j Nock l_j..;o ft. thick) yd e. on j i18M r loam (i ft. thick) _cu. yds. ,+ /e) q Topsoil k6w thick) U cu. ydto rumping Tank Capacity$ 1 %Or gal tank is) lwnpint rate 30 rallo»s / cycle with at lentit 11 cycle•/ fay this 1noludes draltsback caiculntion kb) Reserve capacity 7U gal k9es enclosed design) 1,ump Size 1 Ilr tgau/min) 30 m Install an Alarm system in tits house to indicate pub !'allure metal.!$ both a sound and a light alarm. Perforated distribution 11pe 11i one ter ' 2 1.inoal ft. !! .3 perforated holes space at _" @part. Sotbackec . . Tanks from property line from well % Ir,)1" huli�l� 'rreatreent Area: 1'.•0:3 lake frog$ st enj-!• !Tom property line n 1 :'ron� well �'� i'rom bu�.1��.nGs i j from trees I' MOUND DESIGN WORKSHEET (For Flows up to 1200 gpd) A. FLOW Estimated L4 rJ gpd 3 'a—& or measured x 1.5 a gpd. B. SEPTIC TAMC LIQUID VOLUMES a - / o 0 o gallons C. SOILS (refer to site evaluation) 1. Depth to restricting layer • 3 ' (4 inches 2. Depth of percolation testa f a- inches 3. Percolation rate .Mo mpi 4. Land slope _. . c., D. ROCK LAYER DINIF.NSIONS 1. Multiply flow rate by 0.83 to obtain required area of rock layer: 0.83 = x 50 gpd x 0.83 sq. ft./gpd = 3—`1 sq. ft. 2. Select width of rock layer (10 feet or less) _ �o 3. Length o4rock layer = area + width = Io sq. ft. + /o ft. _ . ft. :. ft. E.+1lmaled Seva1e Flo -s .n Gsllorts per day (1pd) umocr Of Type t T pe 11 Type 112 r1Vpt 13odroonm #- Nr AW -W 0 Ito 1 std 2 300 227 too 2.00 3 430 200 211 ao� 1 600 277 2.76 r a. •r.• 3 730 4" 291 0 Nl 6 900 723 232 71010 Clay 600 270 H 1200 677 101 .�.... Rork Bed atr. war c....N. a PA-. N.•r•r dM.a�a Raasd AStOrpN+a +•dN to lock laver u►dth l+s.i mar -•a S. Cas—h #- Nr AW -W 0 Ito 1 std 1117 too 01 to 7 •• Fina Sand •• 060 2.00 6 b 13 S«d7 Lowe me 132 16 I&A LOS" Rork Bed �GrUw Stnl iltaetlre pt 'I-1 /o o"m foot Raasd AStOrpN+a +•dN to lock laver u►dth faalarYun 0 1 Cow steel ,.,.,.,..•,•,•,., ,.,•,•,•,•,.,. vidth 510 It. 0 Ito 1 std 120 too 01 to 7 •• Fina Sand •• E. ROCK VOLUME Lenst 1. Multiply rock area by rock dept.'s to get cubic feet of rock; •} /U sq. ft. x ft. _ cu. ft. 2. Divide cu. ft. by 27 cu. ft. Icu. yd. to get cubic yards; LjJQ_ cu. ft. -* 27 - J6, J- cu. yd. 3. Multiply cubic yards by 1.4 to get weight of rock in tons; j cu. yd. x 1.4 ton/cu. yd. _7 tons. r- <<,l9u F. ADSORPTION WIDTH 1. Percolation rate in top 12 inches of soil is 3j.�- mpi 2. Seler'. allowable soil loading rate from table; gpd/ftp 3. Calculate adsorption width ratio by dividing rock layer loading rate of 1.20 gpd/ft2 by allowable soil loading rate, 1.20 gpd/ft1+ ,'"0 gpd/fe - .)- 'Yc,, 4. btultiply adsorption width ratio by rock layer width to get required adsorption width; ��,`{0 xft= ft Nbv„ pflo. wt,:•a SWng Table M'..0011 Aa• 1n �linulta Iwcfl (MPI) �GrUw Stnl iltaetlre pt 'I-1 /o o"m foot Raasd AStOrpN+a +•dN to lock laver u►dth faalarYun 0 1 Cow steel —. -- 0 Ito 1 std 120 too 01 to 7 •• Fina Sand •• 060 2.00 6 b 13 S«d7 Lowe 0 79 132 16 I&A LOS" �1 ros7 = S,b L. V.%Lown �sy 0 Nl 300 /t0 to 1:0 9 is Slower thaw Clay — - - 120. • sa.l 100 cootie for 1nstallattow of a uwdard /)aam. See Tow 01 70 st,e' to 2 1e '6 •• Se.l 1tar.n 30♦ - "Mm of fine ted Pius .er7 rand. ••• S.,.1 too Ness for m1ukr%ta0n 04 t eland vd ryl•ent. see '060 0:10 Ubp 1 1. pale 1 T G. DOWNSLOPE DIKE WIDTH 1. If landslope is 2.9 percent or less, basal width includes both the upslope and downslope dike widths, 2. Calculate minimum mound size based on geometery: a. Determine depth of clean sand fill at upslope edge of rock layer: Separation /,U feet b. Multiply rock layer width by landslope to determine drop in elevation; Slope Difference 10 x CA—%+100= 0'a feet c. Add depth of clean sand depth of clean sand for �..,. t I d( 2 d t f k I --- 11 l 694t'04( V 3.�a 3.0� 1 6.r 11.a separation a ups ope a g6t:a) to ept i o roc ayer to ._...�,.,.. rock depth and the depth of cover to find the total mound height at upslope edge of rock layer; /.o ft + 1 ft + 1 ft = 3.6 feet k(' d. Enter table on page bottom with landslope and upslope dike ratio. Select dike multiplier of 3-S 7 e. Multiply dike multiplier by upsic.pe mound height to get upslope dike width:3--Y� x 3, c, = // feet f. Add the depth of slope difference (2b) to [lie upslope height to get the downslope heightG,;, +3-o =,3, �) feet g. Enter table on page E -IS with landslope and downslope dike ratio. Select dike multiplier of 14-S-11 h. Multiply dike multiplier by downslope mound height to get downslope dike width: ,S x 3. J = / feet I. Mininmum mound width is the sum of upslope dike width plus rock layer width plus downslore dike width; J1 ft + /o ft + /S ft. 3 feet R«ki4%4 j. Subtract the Minimum width G i from the Absorption width FA to find the Additional Downslope req.iired for Absorption ZS' ft - 3_ ft = feet Up k. Add the Additional Downslope required for Absorptic to the downslope dike width and recalulate the Total Mound Width which is is the sum of upslope dike width plus rock layer width plus downslope dike width ft + /0 ft + /5— ft = _-36 feet 1. Total mound length is the sum of upsloi -e dike width plus rock layer length plus up.11ope dike width; —L ft + _t/L ft + 1L ft= (03 feet iziC..W th i.l 61 wm tiv it 11 71 it 41 141pe S1 61 71 @1 a.N. 0 iA 40 SO 40 70 So 40 SO 60 70 i0 1 U111, 6.17 136 an 7S1 1.1 I14 476 1K 414 741 114 6QX11 "143 717 1116 7711 PIS ti]S7 44 1SA 114 Son •14 S7• �b 61.5 1' 71A1 6 IS 7 M • '1 161 145 t 1 17 1 M 3 46 6 06 !.� 667 4S7 In 77 741 71) 100 1Q SI• 1111 6 Ill 711 •TA ,707 7Sl )n lr 611 Ih 1111 1 "AA s•" 7M IOH t)') 1" 111 170 In 170 SU 4 in it 41) II S4 1 11 111 Im 1s7 141 Ih 1� • 411 l7S •U I)M 14.7 1M 1M 1� 1.0 110 I.S I0 11• 647 10 (i I S (Irl 1111 ill 7 46 Ill ITS 411 4 M 11 1M 714 II 11 1761 N'/1 176 770 113 161 1" 4 17 444 740 17 SO 1144 11'11 771 7N0 )q 1100 it /r A. Determine PUMP capacitr. 1. Minimum suggested is 600 gallon 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 gpan) to prevent build-up of ptew re in drop box. 3. Use value from design of pressure distribution swtem. SELECT > LMW CAFAMY _':�c Spm B. Determine head sequirementst 1. Elevation difference between, PUMP and point of diKharge. 2. If pumping to a pressure distribution system, add five feet for pressure required at anwo*fold , _5_ feet 3. Friction loss a. Enter friction loss table with gpm and pipe diameter. Read friction las in feet per 100 feet from page F-18. C F.L a Z S -5 ft./100 ft of pipe b. Determine total pipe length from pump to discharge point. Add 25 percent to pipe length for fitting loss, or use a fitting loss chart. Equivalent pipe length -1.25 times pipe lentath • x 1. , feet c. Calculate total friction las t;y multiplying friction loss in h/100 h by equivalent pipe length. Total friction loss a_ x / , s 5- «100 a feet 4. Total head required is the sum of elevation difference, special head requirements, and total friction loss. �9 (1) (2) (311 _ TOTAL HEAD feet C. Pump selection I . A pump must be selected to deliver at least _ gpm (Step A) with at least feet of total head (Step 9). D. Total Puatpout Volute I. To maximize pump life select sump size for 4 to 5 pump operations per day. gpd + 4 a /i 3 gallons per dose 2. Calculate drainback 1. Determine total pipe length. A, o feet. 2. Determine liquid volume of pipe, / 7 `,, gallons per 100 feet. (see page F-18) 3. Multipiy length by volume.. Drainback quantity C, (� feet x / L. L gallons/ 100 ft. • /7 , { gallons. Su98ested drainback quantity is 10 percent of pumped quantity. A larger drainback percentage will decrease pump station efficiency slightly but pumping energy costs am usually a relatively small part of the total household energy, costs. 3. Total pump out volume eyuais dose volume + drainback /l,.2--Qallons per dose + / % gallons a _ / C Total Gallons Pipe LAngth Point of D F1es►atioa Diflereitce EZZ-- F-18b 1.3 isr h 2.0 inch 3.0 inch 1FM nis Pa 100 ft of + 10 0.69 0.20- 2_ 12 0.% 0.28 s .14 1.211 0.38 • 16 1.63 0.48 7 18 2.03 0.60 e 20 2.47 0.73 0.11 2� 3.73 1.11 " :6 5.23 4-W;> 33 7.90 L06 0.30 40 11.07 L64 0.39 43 14.73 3.211 0.48 50 3.99 0.58 35 4.76 0.70 60 5.60 0.82 D-7 0 a.a.Loas r Of +cseceNce 2 300 maid , Z" 300 I b 2_ 4w 777 :,a Ise s 73o 470 no • Ow 327 332 7 1090 f00 370 e 1200 ars 4" 1.25 7. 1.5H 2_ 1 2.5 2e 3 3� 4 F� /yl H is F co/_ /- J E-4 LAYIER OF GEOTEXTILE LOAMY SAND CAP FABRIC PERFORATED LATERAL C 1/Z�' GRASS COVER 6 INCHES CLEAN SAND FILL TOPSOIL 5 MAXIMUM SLOPE S� ,a- TO I " - J .C) A TOPSOIL3 CLEAN ROCK q PLOWED OR /4 TO 2'/2 INCHES � SUBSOIL . DISKED SURFACE /• SLOPE CROSS S CTION A - A PIPE Ftm i PUMPING CHAMBER ' /n Y ---- PERFORATED t ( r LATERAI.S I •• � i I I •� / , BED AREA ' I =' I I 2u 20 0 4 20 INCHES !NC- E DIKE ---L.JO FEET MA X. --t- DIKE I TOTAL WIDTH PLAN VIEW "PRESSURE DISTRIBUTION SYSTEM 1. Select number of perforated laterals 2. Select perforation spacing a �_ feet. 3. Since perforations should not be placed closer than 1 ft. to the edge of the rock layer (see diagram), subtract 2 ft. from the rock layer length. ft. 3 y feet. , Rods soya1.nOth 4. 5. 6. 7. Determine the number of spaces between perforations.., Divide the length above by perfc: :::gin :,pacing and round down to nearest whole number. Length pert. spacing .�1 ft. + ft. i spaces (3) (2) Number of perforations is equal to one phis the number of perforation spaces i 3 spaces + 1 - T- perforations/lateral Multiply perfor- Hons per lateral by number of laterals to get total num perforations. 1...r.+. X �fs�lr.r.i' ..1.sC perforations. uir d fl b 1 1 IV 0+0 1109MORATION M A PROPORATm LAMP&L TNrY , Larw M {• M*G rMrM to tiv Lae" /M tor-- ,,•,,r�� M�.w r+�l •wed ►.�.,Ztwo crow wi WO101 wCqP N•r M ' '' ra.anw IJMfN « _ . c,..e tlaa. t.r. « t..t.o ed TAILS OP MPORATM DOC HARCrS M CPM Head rerforadon dlanrter (I Aw) I W r/a inc 14 21 036 .13 1s 0.61,;, 0.90 2.Or o� .. 1.04 2.s OAV ' ' 1.17 3.0 0.94 . 1.22 4A 1.13 1.47 s.o 1.0 1.43 •Use 1.0 fool of head for neldendal rystowa. ►Use LO feet of head (mother estabUshmw.- 1 �;— I W inc inc 14 21 _) .13 C 11� 26 3J 12 16 23 4.0 " It Is 23 3.0 10 14 22 Determine req a ow rate y mu tip yang number of perforations by flow per perforation X �f gpm. 8. If laterals are connected to header pipe as shown on upper example, to soled minimum required lateral diameter, enter table with perforation spacing and number of perforations per lateral. Select minimum diameter for perforated lateral inches. 9. If perforated lateral system is attached to manifold pipe near the center, lower diagram, perforated lateral length and dumber of perforations per lateral will be approximately one half of that In step 8. Using these values, select minimum diameter for perforated lateral = inches. „ now" 16"a r OF •+eawrr ool-wom "no w 00-0-0 i • LAYOUT OF PERFORATED PIPE LATERALS FOR PRESSURE DISTRIBUTION IN MOUND PERFORATEC PLASTIC PIPE . P OR 36' N SPA01Np . PERFORATIONS SPACED 30 RA�/0 ENDON CENT7ER. PERFORATION PERfO V EW SI Y BE 3�1i, 7�32� _ ��.' OR A �— MANIFOLD PIPE PERFORATIONS ON BOTTOM OF PLASTIC PIPE ENO CAP 40" LAf .PERfpRA NGtN pf �E A% -� _ (ALTERNATE LOCATION OF F:PE FROM PUMP) Q ce N, PI FROM, PUMP G t�►OBER REDWOOD, CEDAR OR ' • TREATED POST (4 x 4 min) --, :..ALL ELECTRIC CONNECTIONS ' . MADE INSIDE BOX • 6' SPACE . " WIRE FROM POWER •` • ` SUPPLY r• . WATER TIGHT &' LOCKABLE ELECTRIC BOX �— PLUG. OR ELECTRIC CONNECTIONS � 20 PVC. CONDUIT SC,H. 1 80 MANH JiF COVER CHAINED B LOCKED oop FINAL GRADE • . - AT LEAST 12 -GRAD •.. ' �BELOW %OP OF POWER CORD .:,:'� • PDR SETTLEMENT PLASTIC ROPE OR CHAIN WITH ANCHOR . ALARM FLOAT ON SEPARATE •s' .' ELECTRICAL CIRCUIT . ' .. START LEE,,, _Z _ �.-• --130 '. PUMP CONTROL FLOAT l HH I Ty 75P SEALED MANHOLE RINGS IPE 'S LAID ON A UNIFORM SLOPE FROM r?_ MP STATION UP T 0 SOIL TREATMENT AREA FOR PROPER DRAINBACK —SEALED TANK COVER IF PIPE AT TANK MUST BE LOWER THAN UNION TO GET ELEVATION FOR DRAINBACK, --A 1/4 INCH WEEP HOLE MUST BE USED — WEEP HOLE NOTES= ELECTRICAL WIRE FROM POWER SUPPLY . MUST BE LOT AID BESIDE OTHER MER ANY TASNKKSS AND MUST BE PLACED IN CONDUIT ALONG POST 2 ELECTRICAL CORDS FROM PUMP AND FLOATS MUST BE RUN THROUGH CONDUIT. WIRES CANNOT HAVE GROUND CONTACT. LOOS OF SOIL 130"INtIS Location 01C. Project --L) � �...�. borings made by /��: r' / bat! Classification System: AASI10 USDA -SCS j ; Unified 1 other _ Auger used (check two)- Iland or hover _1 711pht _� or Bucket '___I other _ Depth, ooring number Drpth, horin► number �- in Surface elevation In Surface elevation feet feet I 0 — 1- 9- 10 — i End of boring at S fast. Standing aster tablet Present at test of depth, hours atter boring. Not present in boring hole_. mottled 60111 Observed at CA�t of depth. Clot present in boring hole �Otr-Yl1, WaLek Ce.— zo y Ap6Q.1 f 10 — End of boring at �� feet. Standing water tablet Present at feet of depth, hours after "rinit. Not present In boring hole Mottled 80111 Observed at f�E. ��depth. Not prontnt In hntlnp holo, LodS OP SOIL bohlNdg Location or. Project �-JC��,�//f'�G��iQ ��"V boring$ (rade by _ «C� b4te . (� Z 9 Z, classification Systew AASIM USDA -Sri X Onitied t other Auger used (check two) I Hand K or Power ____t MOM , —. or bucket , i other .Depth, Boring nuwbdr ._._ Depth, hotlht nuMet In SurfAce �levatlon in Su face olo«atlon feet � � feet /. D �Lcn7y% � ( /L• i, 7 _001- 0 0 (&Aek End of boring, at �feet. Standing water tablel Present at feet of depth, hours atter boring. Not present in boring hole_. Mottled soils Observed etJ3et of depth. Hot present in boring hole 10 — Aot C.4 -A, Z 2:10 end of boring at feet. Standing water tablet Present at feet of depth, hoots atter %orinit. Not present to boring hole X ___- mottled 90111 Observed at Oil oe'depth. 'lot rrooent in horinp of ie N e-39 PERCOLATION TX8T DATA 811221 1 J j �• Test hole location S: r'� ► ;'; �; h Hoi��iuibar / L ` �' k i �/ Date test hole was preparedG^ `� 1 y_c Depth of hole bottoso %-7 inches. J DiaMteri of • hola il I ',(-r : ► in�had �' . Soil ,data from test.hole1 Depth, inches soil texture Method of acratdhioh'&id*WAll a5' Depth of pea-sixed••gravel•in bottom of hole, Z inches&•- Date and' hour W ihiciai water filling _(pj -?-(d, _!' Z . ' Depth of initial water filling, )'L inched above hole bottom. Method used to main ain at least 12 inches o *ter depth in hole for at least 4 hour* Percolst ioh' telt" lreddinid'aide' bpi ' QC/� ,starting at,*•"'' , (date)— •a• during test, % inches. on Maximum *star, depth above hole bottom Time Time Interval, Minutes• Measurement, inches Drop in vater level, inches Percolation rate. minutes per inch Remarks C il <4v G v _ 1 Percolation rate - _ 04�M1 V minutes per inch. O -J7 PERCOLATION TROT DATA 811RLT Time Interval. Minutes M Drop in water level, inches IIA t Remarks � yl. Teat hole location_ �''�j '�� (� lye%�9��..' 4/V Hoid' flturber 2� ��-t4 W" Date test hole was prepared Depth of hole bottom# /-,L inchek/ Diameter 'of hole j, ' inthedt' Soil data ,from test holet • Depth. inches-, Soil textut� -- h ` _ mac'•' l/3�oC� �� �� �./a'`� ' �C r1 ��_` Method of*cratehink'sidewall ICU,� Depth ofpea-sited-gravel in bottom of hole. �Z inches& Date and' hour oC lhitiai Vater filling (r� T Depth of initial water filling. /2 inches above hole bottom. Method used to mrinta n at least 12 inches of water depth in holt, for at least 4 hours S j Percolatiod' telt ' iceddingd'mdde' bt ' ;�- on ?-7starting at a.m. Maxirum valet, depth above hole bottom date) ,.,..., during test. �� inches. Time Time Interval. Minutes Measurement. inches Drop in water level, inches Percolation rate, minutes per inch Remarks c% v (, 16 U ly l U Percolation rate minutes per Inch. PERCOLATION TLBT DATA 8112ET Test hole location �`{ - J C, ''Lu'- Mo Noah limber << Date test hole was prep/ted -Z , Depth of hole bottom -L-. aches� Diameter of hole` !' r .. t . �. t.,... Soil data from test hole) ,,,. ,, t „ r Depth. inches • ' ii texture -,-/ -9L Method of, scratehink'/idev/ll ACI -+:_J Depth of'pea-sited.-gravel•in bottom of hole, 2 inrhee� Date and' hour oV ihiiiai Nater filling (o/Z• -Yl % "Z- Depth of initial water filling, ��' inched Rbove hole bottom. Method used to maint in 4t least 12 inches of water depth in hole for at least 4 hours PercolatioIA'telt'tredding/'mAde'bt' _ T�1=- C `L on .sL/U��tarting at /< �`m''. Maxie _ rater• depth above hole bottom �Z date � r ON. during test, �• inches. Time Time Interval, Minutes Measurement, inches Drop in water level, inches Percolation rate, minutes per inch Remarks LO 'Z _ < � c i �. /i k� /S / C; Percolation rate �•�.�� minutes per Inch. 1\_j H d-39 i PERCOLATION TRST DATA 811RET Teat 1,(116 location' 7 '-:� tV�ei�f�'l/J Ho16`�Muiber Date test hole was prepared (,,I Z / I L , Depth of hole bottom, inches:) j Diameter of hilej inthrdl' Soil data from test holes,,,,• Depth, inches Soil texture 1 I Method of,acratehink'Nidewall ) CL-4,� Depth of pea-sited.-gravel•in bottom of ho//le. L inches Date and'hour ot'ihitiai avatar filling �c� ? �Y �� nom, Depth of initial water filling, ) Z inches above hole bottom. Method um•' to mal. Iain at least 12 inches of water depth in hole for at least 4 hours- l,I_'t?'V11�� 1. _ Percolotloii'teit'reddingi's,Ado'by' on w.starting at c e'"r' '. Maxirum water• depth above hole bottom date �., --p.m. during test, inches. Time Time Interval, Minutes Messurement, inches Dru( in water level, inches Percolstion rate, minutes per Inch Remarks lne7 '2 �) t All L� 2 u Percolation rat' `'4 _� � mimites hrr inch. ,