Loading...
HomeMy WebLinkAbout1998-02-21 Septic System Design ReportI S-P TESTING, INC. Steven B. Schirmers • MPCA Cert.No. 627 951 Katydid Lane NE - St. Michael, MN 55376 • (612) 497-3566 FAX (612)-497-5011 State License #394 February 21, 1998 John Rappaport 3067 Farview Lane Orono, Henn. Co., MN This site has an existing on -site sewage treatment system classified as failed due to not meeting a 3' separation from the bottom of the system and the saturated soil according to city records. The tanks are a block type with the first tank being a cesspool which is classified as an imminent health hazard and must be repaired or disconnected within 10 months. This site has very limited space available for a new on -site sewage treatment system. The area proposed for the new system is the only area available. To use this area, the old survey shows a drainage easement at the west end of the proposed site which is not accurate. The new proposed easement is the actual drainage pattern. The change in the drainage easement will require approval from the City of Orono. Approval will also be needed for a 53' setback from a pond (possible wetland) which is connected to Lake Minnetonka. Wetlands have a 75' setback and Lake Minnetonka has a 50' setback for the on -site sewage treatment system. This on -site sewage treatment system is designed for a Type 1, five bedroom home, in accordance with the Minnesota Polluticn Control Agency Chapter 7080 and local ordinances. The soils on this site are SCS soils mapped - HbC - Hayden loam. The seasonally saturated soils were located at 26" to 32" (mottled soil). Due to the seasonally saturated soils, a Pressurized Mound System will need to be installed to treat septic effluent. The bottom of the treatment area must be located at least 3' above the saturated soils A small washout approximately 1' deep is located near the center of the system. At the time of turnover, this area will be filled with original topsoil by turning the soil over into the washout. The soils at a depth of 12" have a percolation rate averaging 4.2 mpi. A pumping chamber will need to be installed to lift the effluent to the treatment area. The power supply and switches must be located outside the manhole and pumping chamber in a weather proof enclosure. A warning device must be installed with a light and sound device, this is in case of a pump failure. The existing supply line exits the house above the basement floor with a pump in the lower level. The proposal is to abandon the pump and flow gravity from the lower level. The manifold and supply line pips : ,,e back drainage to the pumping chamber. The distribution pipes shall have their %:r ids capped. Be sure the rock and sand fill material are clean. The sod layer below the entire mounded area must be turned over, just break up the sod, be sure not to over work. The existing tanks will need to be abandoned, pumped and filled with soil. All neighboring wells are located greater than 100' away from the proposed treatment area. Keep all heavy equipment off of the proposed treatment area before and after construction. The treatment area should be marked off before construction. This Design is not valid & the system will need to be relocated if failure to protect the arf .is proposed for On -Site Sewage Treatment occurs. With proper installation and maintenance, th; tem should have no problem treating septic effluent effectively. 2 Nothing other than human waste, toilet tissue, laundry, s`,owers, water softener etc. should be disposed of into the septic tanks. Iron filters must be diverted out of the system. Garbage disposals are not recommended, due to adding more solids & fine solids passing through to the system. Excessive amounts of soaps, cleaning agents & chlorine agents may kill the bacteria needed to treat septic effluent. Additives are not recommended. Recommend to pump & clean your tanks through the manhole by a certified pumper every 2 years. Check with your pumper to set up a schedule. Steven B. Schirmars 3 z 0 r, f It YS � fir Y V, MOUND DESIGN WORKSHEET (For Flows up to 1200 gpd) A. FLOW Estimated gpd or meat _d x 1.5 : — _ gpd. B. SEPTIC TANK LIQUID VOLUMES I-) 3,s0 . 1 -'Inn 0 b�s C. SOILS (refer to site evaluation) ptp� la inches 1. _ to rsstrfcdt►g layer = +,;�:,.� 2. of Pa' bests = _ inches 3. Perookdon raX mpi 4. band slope 4 % "'o'IT.t I TM»tt ITy" III I1ypry 2 }� t0 M N • a* )" W h •.� s no -on I 3" tao JIM 7 too iio a eels >+ f • _ 04 �Ra 1a11 lun 708 VW 9 2=66 (A31 D. ROCK LAYER DIIvQ1'NSIONS 1. Multiply flow rate by 0.83 to obtain required area of rock layer. A x 0.83 = _ISO , gpd x 0.83 sq. fL/gpd ■ �_ sq. ft. 2. Select width of rode layer (10 feet or less) ft. 3. Length of rock layer • area + width = Rock Bed th $10 h. E. ROCK VOLUME t-- Lao�~ 1. Multiply rodc arts by rock depth to get cubic feet of rock; sq. ft. x "�.L ft. cu. it. 2. Divide cu. ft. by 27 cu. ft. /cu. yd. to get cubic yards; cu. ft. + 27 = .,d 4 cu. yd. 3. Multiply vAk yards by 1A to get weight of rock in tons; "_ cu. yd. x 1.4 ton/cu. yd. _ _-� -j tons. F. ADSOR3" LION WIDTii Ltd �c,u ►, ,� M,,,�, 1. Perco'ttior► rate in top 12 inches of soil is . Z.mpi P. �.,. Salk 4 ,.., sail suau� �.� W. "Wo .fto Z Aect allowable soil loading rate from table; Fat o thtwo 0.1 ne 1 . S g'Pd / f P 0.1105 s ni mm sme• Ila OAo 2.00 to 1s UWr t.o.n► 0." 132 3. Calculate adsorption width ratio by dividing rock layer ;45 s tasm 0500 2.40 loading rate of 110 gpd/ft2 by allowable soil loading rate; 61 a 6 0 �t� 025 .67 23.00 1.20 gpd/fts+,;�,� gpd/ft: _ 90wat 30 — — •!r trR�aM w ww d M w.� Mc 4. Multiply adsorption width ratio by rock layer width to get required adsorption width; aLk, x /0 ft= .eft G. D(v SWIM'? w117M 1. If landslope isla more, subtract rock layer width from adsorption width to obtain minimum downslope dike toe .. 1 ft- .P_ ft = ''� feet 2 Calculate Mininmm. mound size based on geometery: a. Determine depth of dean sand fill at upslope edge of rock layer: Sepa wioni t feet b. Multiply rock layer width by landslope to determine drop in elevation; Slope DifJemce sor•r•tloo /.._ x % + 100 = . feet U11414q w111% c. Add depth of dean sand for separation (2a) rest at upslope edge, depth of rock layer (1 foot) to depth of cover (1 foot) to find the mound height at the upslope edge of rock layer, Ly` ft + lft + lft on ` • L het d. Enter table with landslope and upslope dike ratio. Select dike multiplier of ? . � t . e. Multiply dike muldplier by upslope mound height to find upsiope dike width: - . -� ­ x • = feet f. Add depth of clean sand for S7^^- difference (2b) at downslope edge, to the moues, nt at the upslope edge of rock layer (20 to find the downslope height; ft+,-, ft = feet g. Enter table with landslope and downslope dike ratio. Select dike multiplier of h. Multiply dike multiplier by downslope mound height to get downslope dike width: - x - feet i. Compare the va.ues of step G.1 and Step G.2h Select the greater of the two values as the downslope dike width, feet + t toot cover t root R• •• Lri toot Stop* Otttor••s• R•cf Bed Width Ifft Dfr•11f1oN Width toot ussls•f rl•tf j. Total mound width is the sum of feet upslope dike (G.2e) width plus rock ..r layer width (D.2) plus a �••,�•• Wilk downslope- 1«1 dike width(G.2i); ft + ft + - ft = _ 4 feet a k. Total mound length is the sum of upslope dike width (G.2e) plus rock layer length (D.3) plus upslope dike width (G.2e); ft + . - h + ft = feet feet T61111101111% it* tl 41 1.1 at 't 21 11 SI 61 71 s1 p +� 1D sD a0 70 30 40 So 40 70 W 40 711 1 1r L17 LIPSa2o 6A 7s L14 Zsl 2" 7ss 1A ♦71 w s« Si atf Lt4 2 S 1a0 1� Ls ak sell Sr 7s2 asIn ll7 ui so 4a1 s7f ss1 asi asy 141 L21 L0D Lz a0 7p 0.72 14" 2.Y 111 I43 LU C17 400 LQ s.lf 11 s S 1is 1r Is si 744 Us av 2s1 » 3.12 30 1JD L41 La L111 110 sal s.0 7 AM La sst 1r 7r 1L11 11i11 fill 16.f1 2s2 1.01 LV L: w t s� L1f Li 1101 t<s2 LU 1« 2b s.st 17s Lu 110 i � fOD troll Ism 17AS 21�1 10A1 2�1 221 2Jf 1L1 loos •� 440 S 7 M 1210 21.as Un 121 21D 349 11p lr 12 F-17 Ft a"-e.iuc nN P20CMURE ee RMOMrer v , repro,. *to L,•twk A. DetsSrina ptudp npaciy: 14 •� d-- Gravity Diawmtioa **+ 1. Minkintan soSpsled is 600 gallons per hour (10 pm) to stay ahead of i. a+.� • . ,-. . water use :rift. 2. Mardteatan sug esud for delivery to a drop box of a home system is 2,7W pUM per hoot (45 Spat) to prevent build-up of pressure in drop box. � C� ••« Fre"11" Dkdbud= 3. a. Slott number of perfaaled laterals - b. Seim perfmatlan epadllg • --.I- het c. Subtreet 2 ft fmm the rock latr elength. -2 ft. Lc d. Deto mire the ttmit s of spaces between perforations. Length pert•spsdrtg ■ _JIL - ft • �- I ■ spares e. ttpacas + 1 ■ ; pedaeaelaaVlaes: f. Multlply psrforatrons per lateral . bynumberof laterals to ) y' get total number of perfamtlons. x g-;6� ■ : perforations. g. c" x>;�p • `�. SPm- SELECT D FUI7 CAFACr Y J L- Spm a. Dewa%bw bad regnit =intsc 1. Elevation difltrerwe between pump and point of discharge. _-7 feet 2. If pumpinS to a pressure distribution "stern, five feet for pressure required at rnardfold if gravity system, zero. _-9 feet 3. Frktion loss a. Enter h coon loss table with gpm and pipe diameter. Read hietion loos ln fact per 100 feet from table. F.L - 3 , y ft./100 ft Of pipe b. Detatdtw toes) pipe Length from pump to discharge point. Add 25 percent to pipe length for fitting low or use a titling loss chart. Equivalent pipe length -I M tunes pipe Length ■ �,�_ x lM ■ �_ feet C. CAk%kte total frktioa lots by multiplying friction loos in ft/100 ft by equivalent pipe length. Total ttietlon loss ■ +i x " -1 •100 a . �- feet 4. Total hssd required is the sum of elevation difference, specW head eecluirennenb, and total friction loss. + 5� + (i) (2) DO TOTAL HEAD ) i feet C. Pump Selection 1. A pump must be selected to deliver at least q c, Spm (Stop A) with at least 12 feet of total head (Step BY 94M rr tow ~~ do V Ono 1.0a 0.56 0.74 2.Ob 0.80 1.04 a. Use for single family homes b. Use for all other applications PIP LMO Point of D.,, to Ch T4:� I':7av�Or1 Diffentooe I ., P j F-18b 13 inch 2.0 inch 3.0 inch am t>AWMi=/■Iafldpp to 0.69 0.20 12 0.96 0.29 14 111 0.38 16 1.63 0.48 it 2.03 0.60 20 2.47 0.73 0.11 25 3.73 1.11 0.16 30 5.23 1.55 0.23 35 7.90 2.06 0.30 40 11.07 2.64 0.39 45 14.73 3111 0.4e so 3.99 0.59 35 4.76 0.70 60 5.60 0.92 S=P TESTING, INC. Steven B. Sd mem - MPCA Cert.No. 627 951 Katydid Lane NE - St. Michael, MN 55376 - (612) 497-3566 FAX - (612) 497-5011 State License $394 John Rappaport 3067 Farview Lane Orono, Henn. Co., MN Borings completed on 2-16-98, with a hand bucket auger. SMUG NUMBER J. Elev.937.8 - M„ , i LED SOIL AT 26" - no standing water present in the bor ft. 0 - 10" Topsoil dark brown loam 10YR 312 10" - 14" Gray brown loam 10YR 512 14" - 26" Brown Gay loam 10YR 516 26" - 42" Rusty brown Gay loam 10YR 5/6 - mottles 614,618 47' - 48" Rusty olive brown loam 10YR 613 - mottles 6/1,618 1110IN&A NUMBER • Elev.937.5 - MOTTLED SOIL AT 30" - no standing water present in the boring. 0 - 14" Topsoil dark brown loam 10YR 3/2 14" - Zr Brown loam 10YR 514 18" - 30" Blown day loam 10YR 516 30" - 48" Rusty brown day loam 10YR 516 - mottles 6/1,6/8 Elev. 939.5 - MOTTLED SOIL AT 37' - no standing water present in the boring. 0 - 12" Topsoil dank brown loam 10YR 312 12" - 22" Brown loam 10YR 514 22" - 32" Brown day loam 10YR 516 32" - 48" Rusty brown day loam 10YR 516 - mottles 6/1,6/8 CERTIFICATION NO.627 STKM LICENSE NO.394 PERCOLATION TEST DATA SHEET Percolation test readings made by S'P on 2-17-95 starting at 9:33an- Test hole numbers, Date test hole was preparedly-1¢9. Depth of hole bottom 12 inches. Diameter of hole ¢ inches. ,AM DATA FROM TURT HOLF DEPTH,INCHES SOIL TEXTURE __.... _..0 - 12" Topsoil dark brawn loam Method of scratching sidewall is j a& Depth of gravel in bottom of hole is Z_imAn. Date and hour of initial water filling 2-16- 11:30am. Depth of initial water filling is 12.jackm above the hole bottom. Method used to maintain at least 12 inches of water depth in hole for at least 4 hours is Maximum water depth above hole bottom during test is 6 inches. measurement, Drop in water revel, Percolation rats, - - �_____Tiune TWO inlervai,min inches inches_ mirwtsspW inch Remarks L-9:12 prefill. 6 - -- --__ 9:33 - _-, 9:48 6 3-7/8 _ - - 3.9 15 min 6 3-7/8- _ -- 3_9 _. 15 min _ 10:09_ - - 10:24 - 6 3-3l4 - _-+-- 4 _ 15 min i I � Percolation rate =12 minutes per inch CERTIFICATION NO.627 STATE LICENSE NO. 394 PERCOLATION TEST DATA SHEET Percolation test readings made by S-F Testier im on 2-17-2$ starting at 9-.%=- Test hole location 3067 Faryiew Le. Orono, Test hole number-1 Date test hole was prepared 2-I6-91L Depth of hole bottom 12 inches. Diameter of hole 6 inches. DEPTH, NCHES -0 - 12" TOPSW dwk brawn kom SOIL TEXTURE Method of scfatcKng sidewall is kaik. Depth of gravel in bottom of hole is 2 ischm. Date and hour of initial water filling Depth of initial water filling is 12-iWjka above the hole bottom. Method used to maintain at least 12 inches of water depth in hole for at least 4 hours is Maximum water depth above hole bottom daring tM is 6 inches. Meml I - I - Drop in k". PEC01110011 ra*' Time_ ._. Tkn Wdwvsl.min WIGS n*adn MK Wah RwwM 9-12 on ill 1 6 1.3� 1 9:49 6 3-9116 4.2 15 min 9:50 10:05 6 1 3-9116 4.2 15 min 10:10 10:25 6 3-1r2 4.3 15 Min 1-7- Percolation rate = 42,minutes per inch. SANDY LOAM $OIL — AT R OF PICHES OF I'/OR 2• PIPE hom PUMP • :+' /� �� cLEAN21Aa1tloir IV TOPSOIL/ / PERTS�RAT�d A. DIVERSION FOR ! SURFACE WATER /� 'gyp' FILL B�ryAY�•1`-`�� RRAL _ L4vtR LAYOUT OF PERFORATED PIPE LATERALS FOR PRESSURE DISTRIBUTION IN MOUND PERFORATED PLASTIC PIPE PPpENNRFORATIONS SPKEO 36- s ��m END VIEW S12t EMAY PEgF TION OR y. 16" <YMANKOL D PIPE \C- PERFORATIONS ON BOTTOM Of PLASTIC PIPE - � T 'sIAIT[RIYF LOCA��I 1 .�� OAF PP/MPEE ZINC CAP b, % L61L66L Afto 2 MPE FROM /f fog fff P{Mr GNAWER Or MEL LAYER OF GEOTEXTX.E LOAMY SAND CAP ►ABRIC r-PDWC,„ LITERAL GRASS COVER - CLL i1Ll MAOPC —« r TOPSOIL PLOWED OR �-- DISKED SLIRFKE CROSS SECTION A - A -- PIP't I" PUMPIAG CIIA' iKR PERFORATED I LATERAL I KO AREA I i 92 H I s+g }R _ OIME 10 FEET _j_ 06KE — MAX. TOTAL WIDTH ENO FERFORATHM OF A PERFORATED LATERAL i-Fr Cow T�II • Ir, tW IIIw • � 4 'I� cN.. A.r uF.v M' " of fir. PIrA fwV lwrww wCrw Fable Iw 0ow- is awrA + Now"" N � It, I. low rw of L F-8 .t WATER TIGHT 9 LOCKABLE ELECTRIC BOX — PLUGS OR ELECTRIC CONNECTIONS — 2' PVC CONDUIT SCHEDULE 00 60S MANHOLE COVER CHAINED B LOCKED SEALEZ MANHOLE RINGS ---�t, �,_•__��j SEALED TANK COVER PLASTIC ROPE OR CHAIN WITH ANCHOR --------_"-, ALARM LOATTRICAL CIRCEPAUIT RATE � SHt? - Of F_ FYEt-7 PUMP CONTROL FLOAT �00 TWD'4 T i OR a min) A' I &&URIC CONNECTIONS MADE Box LOOP OF POWER CORD FOR SETTLEMENT r" AT LEAST 12' —P7v LOW GRADE WIRE FROM POWER SUPPLY plpl ftpISS LAW ON�pA UNIFORM SLOPE FROM FOR pRTATOPEpRAINBACM TREATMENT AREA L IF PIPE AT TANK MUST BE LOWER THAN UNION To WEEP HOLE MUST BE USED — WEEP HOLE NOTES: ELECTRICAL WIRE FROM POWER SUPPLY MUST MUST _ � LJUD BESIDE OTHEMDT RUN OVER ANY R TANKS BESIDE AND T 8E PLACED IN CONDUIT ALONG POST .LECTRICAL CORDS FROM PUMP AND FLOATS MUST BE RUN THROUGH CONDUIT WIRES CANNOT HAVE GROUND CONTACT. rigure r•a I 4. " - I CONCRETE MANHOLE RING rHOOS u' SECURING MANHOLE COVER TO PREVENT UNAUTHORIZED ENTRY rigurc t--1- •Jo-- 1 r r1 Al `VERTICAL SIDE*ALL SEPTIC TANK FINISHED GRADE AT LEAST 6' T 12" SOIL ^' LEAST 4" DIA — COVER 4" Q1A.�., I AT LEAST t' AT LEAST I" MiN - A DIMFSNSI N FOR _TANKS WITH V RTICAL-5L0FSS, A WIDTH W 24 MINIM M —� IEIVGTH,� 2 TO 3_ TIMES THE .WIDTH 87�T �'AMETER LO M1NIM_UM _ DEPTH D _ 3C� MINIMUM; 7B_MAXIMUM C A 02 0 _ g 6_"_MINIMUM0.2 � MAXIMUM 6' C 04 0 _ --- - - AT LEAST 4 FEET - -� I 1Srlff 1 I ter«+&41ItttAItr�ll.nutfr+0w�ilrn . Lw■rstowtnitMLLIr.L0�I11[Dwrowlfr.utf f. 1ltrtSim LUCOrIEOnIOIf"We"ES.ICL!'Ast flltwwluttsummon fO41CIFIESUOVACt Wjrj0NAIvtC1Crlrnw.IrlM6lt[I0r Alt TA1{ nt OprLllAtAlti MA/=OIONtfI1R.w, ACCtSR wAlLs f:LfAM147.WINti�fMlNilO(�M[IMFAK/ 7. AM.;'[C+41rfY Or A,.usl...ptf rllA/L 1[lI w(AMSTr'O.H UH*Vf't[&VALK wc!t%f Urw. MGtf OMALMNEt[IIMLt IEtOcAI[Orlrtneo11111t N(t CPHOIQti ntAN11001! Mf)CUILLI DLInI'941N@ CLFflUIL9wCa11f.94V9CI0J S ?OnocoottM I AL CVLfMW--&lAAs1; DAK++RILr+A1f S+A P.[Sf MLLSt1It AAff Afllt C("+LnIM[rWI04 Awn 01V 14VON c IS 0 Wl am I LE OrtMNOf On%*"I N 1f ILES A11r[I WWI f.I c" 1 ' I•.'t 1Ai1KLOcA+►u a lwr rw l/t.At I AN11 A111;t OAT rt[f PEWIL r MANG 26E.. INLET SCUM OUTLET ` •l;;='+jpi "' ET LEVEL _ 7 r SCUM CLEAR SPACE--: T CLEAN OUT TANK W1 EN -T 'X I S 3- OR OR LLEOR SS '1 1 r' t� '1`'� •: SLUDGE 0� COLOR s SLUDGE LAY R I LIOWD MEAc' ::zrE SCUM AND SLUDG ACCUMULATIONS IN THE SEPTIC TANK