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Home My WebLink About1978-03-03 Septic System Desigh Report11 An Expansion of Soil Engineering Services, Inc. B M U B ENGINEERING TESTING I' O MIMMEAPOLIS/ST. PAUL SM S. County Rd. 18, P.O. Box 35109, Molt., Mn. 55435 / 612.941•S600 O NORTHERN MINNESOTA 1 S A:OERS E, V"PnN. 3219 E. 19th AMnw, Hibbing, MN. 55)46 / 219�263�SS89 • v AN OEaSON, Vice Pip garenarw O CENTRAL MINNESOTA 200 Omo Avenue No., St. Cloud, Mn. 56301 1612.253.9%0 C G aN USE I. E.. Nn P—. fnrnwrn, 11 11 11 11 11 u March 3, 1978 B. J. Builders 16546 West 78th Street Eden Prairie, MN 55343 Attn: Ms. K. Ross Re: 78-046 SOIL BORING & PERCOLATION TESTS Lot 5, Block 2, Farview Addtn. Orono, Minnesota Ms. Ross: As you requested, we have recently conducted a soils investi- gation consisting of one power auger boring and 12 percolation tests, to determine the general soil and water conditions, and to provide information relative to the soil absorptivity rates. The boring and percolation tests were taken at the locations as shown on the attached sketch. Field locations were determined by our crew, with reference to the staked property corner. Surface elevations were referenced to a spike in a large oak tree situated approximately 60 feet from the northeast property corner. An elevation of 106.0 was given for this bench mark. Initially, six percolation tests were conducted on the lot on February 23, 1978. As 5 of the initial tests indicated failing results, six additional percolation tests were then conducted on February 28, as requested. INVESTIGATION METHODS: The power auger boring was completed using a truck -mounted power auger unit. The soil classifications and depth shown on the attached log were inferred from the soils brought to the surface by the continuous flight feature of the auger. The depth of strata changes are, thus, considered approximate. CONSULTING ENGINEERS/SOILS AND MATERIALS Test Borings • Fuundation Engineering and Recommendations • Inspection of Construction . Material Testing of Sods. Concrete and Building Components 78-046 B. J. Builders via March 3, 1978 11 11 11 11 n n u 1 1 1 1 I. 1 Mineral soils encountered in the boring were classified in accordance with the Unified Soils Classification System (ASTM D2487). A copy of that chart is attached. Representa- tive samples were then returned to our laboratory for verification of the field classifications by a Soils Engi- neer. Representative samples will remain in this office for a period of 60 days to be available for your examination. The boring was probed immediately after its completion to check for the presence of groundwater. The boring was also rechecked prior to leaving the site on February 24. The absence of groundwater was noted in both probings of the boring to its 20-foot termination depth. The percolation tests were run in 6-inch diameter holes drilled to an approximate depth of 36 inches, in accordance with the procedures recommended by the Minnesota Department of Health (MHD) and with procedures recommended by the City of Orono. In accordance with these procedures, the bottom and sides of the holes were scratched with a knife blade to remove any smeared soil sur`aces and to provide a natural soil interface into which L,e water may percolate. Two inches of coarse sand was then placed in the bottom of the holes to prevent scouring. The holes were then carefully filled with clear water to a minimum of 12 inches over the top of the sand layer and allowed to soak overnight. An insulating material was also placed over the holes to prevent freezing. The percolation tests were then conducted the following day. RESULTS: The log of soils encountered in the boring and the water level observations are shown on the attached Log of Boring sheet. The soil borings and percolation tests generally encountered clayey sand glacial till from the surface to the 20-foot depth, with the top 1 foot being considerel the topsoil layer. Results of the percolation tests indicating these soil absorptivities in minutes per inch (mpi) are as follows: Surface Soil At lest M Elevation Test Depth P-1 102.4 Sandy Clay (CL) P-2 100.4 Clayey Sand (SC) P-3 101.4 Sandy Clay (CL) P-4 99.4 Sandy Clay (CL) P-S 99.4 Sandy Clay (CL) P-6 97.7 Sandy Clay (CL) Rate m i 44 240 240 4 e�un. ENGINEERING TESTING 78-046 ' B. J. Builders -3- March 3, 1978 Surface Soil At Rate Test M Elevation Test Depth (mpi) P-7 99.0 Clayey Sand (SC) 60 P-8 98.0 Clayey Sand (SC) 11, P-9 98.0 Clayey Sand (SC) 22 P-10 97.5 Clayey Sand (SC) 34 P-11 97.5 Clayey Sand (SC) 60 P-12 97.5 Clayey Sand (SC) 10 ' *No water movement was observed during the test process. RECOMMENDATIONS: As can be seen from the above tabulation, the initial tests averaged well above the 60 mpi rate required for a suitable drainfield. However, the average of the 6 additional perco- lation tests is 34 mpi. At a rate of 34 mpi, a minimum of 260 square feet of absorption area per bedroom is required. For the proposed 5-bedroom house, the total required absorp- tion area would then be 1300 square feet. This can be provided by a total of 6 drain lines, each 87 feet in length, 30-inches in width, and spaced 7 feet center -to -center. uur recommended design system is also shown on the attached sketch. If you should have any further questions regarding these data, kindly contact us at your convenience. Very truly yours, UN ENGINEERI EST�ING,, INC. Dennis M. Rietschel Engineering Geol ist �, r Vice President - Engineering DMR/CGK:skh The content of this report and supporting documents are lot the esUusrve use of the addreaee In the absence of our prior wri uen approval we make no representation and assume no responsibility to any other parties regald•ng such content BRAUH ENGINEERING TESTING `D,dVNL/NE tti C -;P -p �Coe y ' '1 LOG OF BORINGS PRO 78-046 Soil Boring & Percolation Tests DATE: 2/23/78 Lot 5, Block 1, Farview Addition Orono, Minnesota SCALE: 1"-4' ■ss: BORING: D_1 LOCATION: See Attached Sketch BORING: LOCATION: SURF. ELEV: 100.2 Depth Description of Materials WL DeptDept4 Description of Materials WL CLAYEY SAND, fine- to medium -grained, with a SC trace of fine to medium Gravel, dark brown to i brown, moist. (Glacial Till) 20 Water level not encounter d when probing boring 10 minutes after completion of boring. Water level not encounte ed when probing boring 24 hours after completion of boring. DESCRIPTIVE TERMINOLOGY PARTICLE SIZE IDENTIFICATION Eoukh n - ovo 3" Oo vw Cwns 1' — 3" Madur" 1 /2" — 1' Fine No. 4 — 1 /2" Fend Coate No. 4 — No. 10 Medum No. 10 — No. 40 Fine No. 40 — No. 100 Very Fie" No. 100 — No. 2 sit No. 200 — .006 rem a" Nee ton Am "rest RELATIVE DENSITY OF COHESIONLESS SOILS vary boa 0 — 4 Ef F NNW 5 — 10 EPF tttedom dww 11 — 30 EPF dune 31 — 50 EPF very drew W MF SOIL INTRUSIONS THICKNESS New 0 — 1 /6" then 1 /6" _ 1" layer 1' — 12" verved alternating seems or lenses of clays and silts in lake deposit MOISTURE CONTENT Dry late than 5% Moist under optimum moisture Met over optimum mobture Wetarbeering saturated and CONSISTENCY OF COHESIVE SOILS vwy soh 0 — 1 SPF soh 2— 3911010 nthar sole 4— 5 5PF nwhi'um 6 — S 6PF rather to" 9 — 12 6PF stiff /3 — 16 6PF very, stiff 17 — 30 IWF herd 30+ MF RELATIVE PROPORTIONS with a fen 0 — 10% with sort" 11-20% with over 20% ORGANIC CONTENT 0-5% non to slightly organic 6 — 10% slightly organic 11 — 25% organic 26 — 05% muck 65+ peat PLASTICITY OF SOILS WITH LESS THAN 20% CLAY non plastic gritty, cannot thread slightly plastic rough to smooth, hard to thread plMtic smooth to waxy, easy to thread RELATIVE PROPORTIONS OF GRAVEL LABORATORY TESTS a erns 0 — 5% DO Dry OwWty. pd OC Organic Content, % a little 6 — 15% WD Nit Owtsity. pd S Percent of Saturation, % eon" 16 — 30% MC Natural Moisture Content, % SG Specific Gravity and 31 — 60% LL Lipsid Limit, % C Cohesion FL Elastic Limit, % S Angle of Internal Friction PI Platieity Index, % 4u Unconfined Compressive Strength DRILLING NOTES: Stendercipsone . 6 n vast bearings wwe advanced by 214" or 311" I.D. hollow -seem ougm unless noted other- wise. Jeteing water was used so civet out atagar prior to sampling only when indicted on logs. Standard potnretion feet boring we designated by the prefix , ST" (Spilt Tubal. Powan sum boringe were advw cad by 4" or 6" diamner, continuous•Nite, solid stem sugars. Soil classification and strata depth we inferred from disturbed samples autiend to the surface and an therefore somewhat approximate. Fortier auger borings we designated by the prefix Shand probing were ad a c d nenually with a I %" filar eter probe end was limited to de depth from which the probe ran be manually withdrawn. Hand probin s are indicted by the prefix "H' CLASSIFICATION: Classification on logs ism by inspection in accordance with the Unified Soils Classification System (see attached chart) uslryt visual -manual procedures union noted otherwise. GROUND WATER: Observations wen made at the times indicated. Porosity of soil strata. seasonal weather conditions, site topognphr, ate.. RW cause chwages in the water levels it food on the lop. SAMPLING: All aneptw we #Olson with the standard 2" O. 0. split -tube sampler, except where noted. TW indicates thin - wall undlsturbod swnt0 - 1PF: Number Indkaa blows per foot recorded in slandaid penatntion vat, also known as "N" value The sampler is of V' into urvdsturbod soil below the hollow tam auger. Driving resistaracm are than counted for second and third E" increments and added to get 6PF. When they differ significantly, they two reported in the IoNowing farm — 2112 tow the second and third 6" ineror"nts respectively. WH: WH lendioates that a lw* penetrated soil under weight of hammer end rods alone, driving not required. NOTE: All tau run in swwdwwe with applicable ASTM standards. Hmon, ENGINEERING TESTING CLASSIFICATION OF SOILS FOR ENGINEERING PURPOSES ASTM DESIGNATION D-2487 Major Divisions L N T � r 'Q' N O {VV r v N L yy,, O ^.�A CA Nignly organic soils Group Symbols Typical Newts Classification Criteria Well -graded gravels and Cu - De0 / D10 Greater than 4 OA gravel -sand mixtures. little or no fines (D )! Ca - DIDX DOD Between I and 3 � N _ In e _ Poorly graded gravels and GP ravel -sand mixtures, Not mmeeting both criteria for OY little or no fines o Sil gqravels gravel- Atterbe limits plot below »An line or Atterberg limits plot- • " GN $an slit mi;Lres plesticity index Ling in hatched area e+ Clayey gravels, gravel- jass than 4 art borderline s p o classlficattons n- b•�•�t r� above A line and quiring use of dual • GC sand -clay mixtures plasticity index symbols o a greater than 7 Well -graded sands and Cu - De0 / D10 Greater than 6 1 � N 8N gravelly sands, little or no fines Ca - Between I and 3 g Q M Die Poorly graded sands and 5 9P gravelly sands. little Not meeting both criteria for 8M N or no fines = to ` s 8N Silty sands. sand -silt Atterberg limits plot below »A line or Attarbtrg limits plot- M M, mixtures plasticity index less Ling in hatched area than 4 :are borderline clan- 5 8C Clayey sands. sand -clay »s plot sill cations squtring above A line and use of symbol s Idxtures greater thann�ax Inorganic silts, rock flour, silty or clayey At fine sand Inorganic clays of low o 60 medium plasticity, yrav- a e11y clays, sandy clays, silty clays, lean clays SO Organic silts and organic OL silty clays of low C' t� Inorganic clays of high plasticity, fat clays Organic clays of medium Off to high plasticity 40 30 20 ►uttecw esirt ftr eta"irtoQtioe of fie - of e0myefra(Med #age and fine�°Otion acea,b.,e tt+.tu totc{rq in ha:Qhad amamIderttl1/ , eta..crcmtion. MqWcrt� r.. of dMat eywW.. iquation of A-1 _ M I� 0O 10 20 30 40 SO 60 70 SO 90 100 Liquid Peat, ruck and other Pt highly organic molls Visual -men wl identification BRAINGUN Ziwit � �snNo BRAUN ENGINEERING TESTING. INC. da00 66 COUNTY ROAD 16, P.O. BOX 35106 • MINNEAPOUS. MINNESOTA 55435 PHONE 612/941-56M I&EMQ-LETTER" TO City of Orono DATE March 13, 1978 P.O. Box 66 SUBJECT Crystal Bay, MN 55323 Attn: Septic System Inspector Based on the information obtained from the percolation tests conducted on the lot, it is our opinion that the required drain - field expansion area can be developed in the area immediately to the south of the proposed drainfield area as shown on the attached sketch. If you have further questions regarding these data, kindly contact us at your convenience. cc B . J . Builders VILLAGE 06 ORONO CERTIFICATION NO.627 STATE LICENSE NO.394 PERCOLATION TEST DATA SHEET Percolation test readings nuide by on 2-17-95 starting at4:32a-- Test hole location RapowrL 3067 Fa_nim La-. Ckmfte. Test hole number-, date test hole was preparedlaW-A Depth of hole bottom 12 inches. Diameter of hole 6 inches. S011L DATA FROM TEST HOLE DEPTH,INCHES SOIL TEXTURE 0 - 101, - 01 dark brawn loam 10" - 12" Gray bry bem Method of scratching sidewall is ksi&. Depth of gravel in bottom of hole is Jjashn. date and hour of initial water filling L16-2L11:30am, depth of initial water filling is 111as►sa above the hole bottom. Method used to maintain at least 12 inches of water depth in hole for at least 4 hours is • L Maximum water depth above hole bottom during test is 1i inches. AAssuxerr�nl, Drop in wain irm. Parcolatb raw. _ _TO* Time interval, min _ inches inches _. _.._ mi wft pw. i ich RI - 9:12 --_ prefill - -- 6 0111 f Q-a7 6 2 4.3 9:52 - Percolation rate = 4&minutes per inch. ----- 8 — _ 3-7/16 _ _1--- __-4.4 _3-W6 , 4.4 f