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Home My WebLink About1979-08-09 Septic System Design ReportBRAUR.'" ENGINEERING TESTING WUNEAPOLIS/ST. PAUL 6800 S. County Rd. 18, P.O. Box 35108, Mph., MN / 612.941.5600 NORTHERN MINNESOTA 3219 E. 191h Avenue, Hibbing, MN 55746 'CENTRAL MINNESOTA 1520 - 24th Ave. N., P.O. Box 189, St. Cloud, MN 56301 DULUTH/SUPERIOR 5431 Airpark Blvd., Duluth, MN 55811 SOUTHERN MINNESOTA 40 - 16th St. S.E., Rochester, MN 55901 August 9, 1979 Mr. Sid Rebers Rebers Construction 3525 Webster Ave. Mpls., MN Mr. Rebers: J S. INAUN LE. P..abn ►H. ANDERSON. vo /m Gbww,ar C.G xA USE ►E.. V—P- Eti.—" DA HAUSLER ►.E,�.or,.. Re: 79-429 PRELIMINARY SOIL BORING 6 PERCOLATION TESTS Lot adjacent to 1045 Edgewood Hill Road Orono, MN As you requested, we have recently completed a preliminary soil probe and two percolation tests to aid in evaluating soil, soil absorptivity, and groundwater conditions relevant to the poten- tial design of an individual sanitary system to be situated at the above referenced lot. At this time, we understand that it is your desire only to eva- luate conditions for a potential system rather than completing the entire series of soil borings and six percolation tests required for City of Orono approval. Boring and test locations are shown on the attached sketch. INVESTIGATION METHODS: ' Due to the existing flower garden situates: in the proposed drain - field area, you requested that we not use our power drilling equipment for this exploratory study. On August 2, 1979, our crew performed a hand auger probe, put down to the 6-foot depth in lieu of a boring. The hand auger probe was used to retrieve samples from varying depths as the ' probe was being advanced, in screw fashion, into the ground. Strata depths are considered somewhat apptoximate using this apr ;-ich. As soil samples were being retrieved, they were imme- diite.Ly visually and manually classified by the crew chief in accordance with the ASTM D2487 "Unified Soils Classification CONSULTING ENGINEERS/SOILS AND MATERIALS Test Borings • Foundation Engineenng and Recommendations • Inspection of Construction • Material Testinr. )f Sods. Concrete and Building Components 79-429 ' Rebers Construction -2- August 9, 1979 ' Syste i and ASTM D2488 "Recommended Practice for Visual and Manual Desckiption of Soils". A .few representative samples were then returne, to our office for verification of field classifications by a Soils Engineer. Those samples will remain in this office for a period of 60 days to be available for your examination. The hand auger probe was checked for the presence of groundwater with the use of electrical water level detector. The initial probing was completed immediately after removal of the auger and ' once again at the time of percolation test readings, conducted approximately 24 hours later. The percolation tests were run in 6-inch diameter holes drilled to an apnrnxirate depth of 36 inches, in accordance with proce- dures re nded by the City of Orono. In accordance with those procedur. -e bottom and sides of the holes were scratched with a knife b. -c remove any smeared soil surface and to provide a natural sc-terface into which othe water may percolate. Two inches o. c - sand was then placed in the bottom of the holes to prevert uring. The holes were then carefully filled with clear water to a minimum of 12 inches over the top of the sand and allowed to soak overnight with the percolation test being conducted the following day. RESULTS: The attached log contains the results of the probe and the water level information. Soil encountered, Ln the probe include approximately 1 foot of black silty sand topsoil underlain by a clayey sand gla-ial till to the 6-foot termination depth of the probe. Groundwater was not encountered in the probe at the time of its completion nor when rechecked approximately 24 hours liter. The percolation tests indicated soil absorptivities in minutes per inch (mpi) as follows: Test Soil at Test Depth P-1 Clayey Sand, brown P-? Clayey Sand, with layers of fine to medium sand, bro% REMARKS: Rate (mpi) 15 10 BRAUR ENGINEERING TELTING 79-429 Rebers Construction -3- August 9, 1979 Results of the percolation tests indicate the area testes' will be quite suitable for drainfield development. The results of the two percolation tests average out to 12.5 minutes per inch (mpi) which is well below the necessary 60 mpi rate required for drain - field development. It should be noted, however, that these results are unusually low for a clayey sand. The layers of sand encountered in P-2 may be the reason for the low rates. Future tests over a wider area may find higher rates. GENERAL: We appreciate this opportunity to be of service to you on this project. If you have any further questions regarding these data or, kindly contact us at your convenience. Very truly yours, BRAUN ENGINEERING TESTING, INC. "Vennis M. Rietschel Engineering Geologist ,e-,&. C. G. Kruse, P. . Vice President - Engineering DMR/CGK:jn The content of this report and supportmq doeume IT, ate lot the e.c ius,.c .,%e or v e addressee In Ihe,Dse,, a of our pr,or -I apotovaI we make no teptesenlation And assume no reWo•t S. o,hty to any other patties rtca,mnq such conic it HRAun' ENGINEERING TESTING I MOWN"% AucEA �ec it , - iwL., r,&.,JW i -*;, —.1. %1- 1�v4a. , " LOG OF BORINGS r JECT: 79-429 PRELIMINARY SOIL BORING 6 PERC TESTS Adjacent to 1045 Edgewood Hill Drive Orono, Minnesota BORING: HA-1 LOCATION: 10RING: See Attached Sketch SMECEV: NOT OBTAINED Depth Descri Lion o oriais D248,WL Depth Da criG 1 SILTY SAND, black, moist. SM CLAYEY SAND, fine to SC medium -grained, brown, muist. 6 (Glacial Till) Water level not encountered wheci probing boring 10 minutes after completion of boring. Water level not encountered when probing boring 24 hours after completior f boring. d DATE: 8/3/79 SCALE: 1"-4' LOCATION: of Motor is (s DESCRIPTIVE TERMINOLOGY PARTICLE RIZE IDENTIFICATION sosus,+rs over 3" Gnewel Coma 1' - 3" Il"um 1 /2" - I" Firsts No. 4 - 1 /2" tend Cosies No. 4 -No. 10 Medum NO. 10 - NO. 40 Fine No. 40 - No. 100 Wry Fine No. 100 - No. 200 silt No. 200 - =5 min Qey lea than AN mm RELATIVE DENSITY OF COHESION LESS SOILS very loon 0- 4 5PF loose L - 10 sPF medium deism 11 - 30 IIPF dense 31 - 50 GPF very defies W MF RELATIVE Petit' 7RT13AIS SOIL INTRUSIONS THICKNEst Mnsm 0 - 1 /8" urns 1I8" - t' Myer V, - 12" waived alternating seems or lenese of cMye and silts in Oaks deposit MOISTURE CONTENT Dry less then 5% Montt under optimum moisture Mt over optimum moisture Watrsrbearing saturated send CONSISTENCY OF COHESIVE SOILS very soft 0 - 1 IIPF soft 2 - 3 BPF rather soft 4- 5 9PF medium 6- 8 IIPF rather stiff 9 - 12 BPF stiff 13 - 16 BPF vary still 17 - 30 BPF hard 30+ BPF RELATIVE ►MCIPORTIONS with a few 0 - 10% with soma 11-20% with over 20% ORGANIC CONTENT 0 - 6% non to slightly organic 6 - 10% slightly organic 11 - 25% organic 26 - 65% muck 66+ out PLASTICITY OF SOILS WITH LESS THAN 20% CLAY non plastic gritty, cannot thread slightly plastic rough to smooth, hard to thread plastic smooth to waxy. easy to thread OF ?L LABORATORY TESTS a tray o - 5% DD Dry Density, pcf OC Organic Content, % a little 6 - 15% WD Wat Density, prof S Percent of Saturation, % some 16 - 30% MC Natural Moisture Content, % SG Specific Grw,Iw, and 31 - 60% LL Liquid Limn, % C Cohesion PL Mastic Limwt, It, 0 Angle of Internal Faction /1 Plasticity Index, % qu Unennfined Cowitwessive Strength DRILLING NOTES: Standard penetration tint borings were advanced by 25G" or 3%" I.D. hollow -stem augers unless noted other- wiss. Jetting wear was used to ck,*n out sugar prior to sampling only where indicated on Iogs. Standard peretraion last borings are designated by the prefi: "ST" (Split Tubal. Power sugar boringe wen advanced by 4" or 6" diameter, continuous -flits. solid stem augers. Soil classification and strata depths are infarred fr m disturbed samples sugared to the surface and are therefore sormewhst pproximass. Power sugar boring are designated by the prefix "B" Hand probing -"re adwertoed manually wwth a 1 h" diameter probe end are limited to the depth from which the probe can be manually withdrawn. Hand probing. are indicated by the prefix 'H". CLASSIFICATION: Classification on Im is., by inspection in accordance with the Unified Sods Classification System (see attached chrtl using visual manual procedures unless noted otherwise. GROUND WATER: Observations wen nude at the limn indicated. Porosity of soil Strata, seasonal weather conditions. site topography, etc., mnay, own changes in the water levels indicated on the log. SAMPLING: All setnptss are taken with the standard 2" O. D. split -tube smmpla, except when noted. TW indicates Stun wall undisturbed srnwit. BPF: Nu lint indcase blows per foot recorded in strtdrd penetration tat, also known as "N" value The sampler is set 6" into ter -disturbed soil below the hollow -stem auger. Driving resistances are then counted for second and third 6" increments and added to get BPF. Mlhere they differ significantly, they two reported to the following form - 2/12 for the second and third 6" increments respectively, WH: WH indieasas that sampler penetrated soil under weight of hammer and rods alone, driving not required NOTE: All "Pate run in accordance with applicable ASTM standards. omen ENGINEERING TESTING CLASSIFICATION OF SOILS FOR ENGINEERING PURPOSES ASTM DESIGNATION D-2487 Group Typical Major Divisions Symbols Nerves Classification Criteria v O 0 4 u s '" u c �' c p� + •si L,su. N G Ev 0 u 4n ' LA N tN N L- «1 U Y � OJ N 9 0 r Cro N Ln J N N ' N A N �a+,On ,� , at Hignly organic soils Well -graded gravels and Cu - De0 " D]0 Greater than 4 0 ^9 GW gravel -send mixtures, little or no fines 0D+ �7! Ca - p10e Between 1 and 3 N Poorly graded gravels ane 0 ravel -sand mixtures. Not meeting both criteria for GW little or no fines N'_ Silty gravels, gravel- Atterber, limits plot below «A� line or Atterberg limits plot- us to + +" '9 CM san s It mixtures plasticity index ting in hatched area c c less than 4 are borderline d$•`t Clayey gravels, gravel- arberg limits p o above «A« line and classifications re - quiring use of dual • + GC sand -clay mixtures plasticity index symbols c greater than 7 Well -graded sands and Cu - De0 I D10 Greater than 6 a w SW gravelly sands, little (D 2 or no fines Ca - DI- Between 1 and 3 B g N N ' j Poorly graded sands and SP gravelly sands, little Not eting both criteria for SW me A N or no fines 6A 2 Silty sands, sand -silt Atterbe limits plot below «A� line or Atterberg limits plot- a` N N d Sw mixtures plasticity index less tiny in hatched area than 4 -are borderline clas- $� SC Clayey sands, sand -clay tte er s plot above A and sifications requiring use of symbols c '" r•8 N mixtures yline greeters thann¢x Inorganic silts, rock flour, silty or clayey AM fine sand norgen c clays of low to 60 med' m plasticity, grav- a elly clays, sandy clays, silty clays, lean clays 50 Organic silts and organic OL silty clays of low 40 plasticity Inorganic silts, micaceous 30 M or diatomaceous silts, elastic silts 20 Inorganic clays of high p, M plasticity. fat clays Organic clays of medium q9 to high plasticity Ptastioity short For otassifieation of fine- -pained soils and fine fraotion of coarse -grained voile. Atterberg limits Plotting in hatohed area are borderline olassifioatione requiring we of dual symbols. lquation of A-li PI - 0. 78 (LL-20 , AB GBf Al 4 00 10 20 30 40 50 60 70 80 90 100 Liquid limit Peat, muck and other Pt highly organic soils Visual -manual identification BRAHR' ENGINEERING TESTiNG