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HomeMy WebLinkAbout1976-12-03 Septic System Design Report' An Expansion of Soil Engineering Services, Inc. BMUR'" ENGINEERING TESTINO 'NIINNEA►OLIS/ST. PAUL 1111110111S. County Rd. IS. P.D.11* 15101, Itlplt., Mo. 55435 / 112-141.5100 NORTHERN MINNESOTA 7219 E. IIM Amos,1,16", Mn. 55741 / 011.2W-q61 December 3, 1976 Sullivan Septic Service 3660 Highway 101 South Wayzata, Minnesota 55391 i.ttn: Mr. Ed Sullivan Gentlemen: J. L NNAU* P. E. Awlsirrt P.X.ANOENAON, VYSNat Daalorla c.e. KNM P. E. We Prss. E f^a D. N. 110NANAN P. E., Vfa RrL Ta ti V Re: 76-301 SOIL BORING & PERCOLATION TESTS lit 4, Block 1 Fairview Orono, Minnesota As you requested on November 24, we have recently completed one power auger and 3 percolation tests to assist in evalu- ating the soil, the soil absorptivity, and the groundwater conditions for the design of an individual sanitary system for the proposed house to be situated on the above referenced lot. You have indicated that the house location will be based on the results of our recent investigation. The boring and percolation tests were taken in general locations as directed by you and as shown on the attached sketch. The locations for the boring and percolation tests were referenced to the southeast property corner of Lot 4. Surface elevations were referenced to an iron located at the northeast property corner with an elevation of 964.3. INVESTIGATION METHODS: The power auger boring was completed using a truck -mounted power auger unit. The soil classifications and depths as shown on the attached log were inferred from the soils brought to the surface by the continuous flight feature of the auger. The depths of strata changes are thus considered approximate. Soils encountered in the borings were visually and manually classified in accordance with ASTM D2487 "Unified Soils Classification System" and ASTM D2488 "Recommended Practice For Visual and Manual Ikscription of Soils". A copy of ASTM D2487 is attached. Representative samples were then returned CONSULTING ENGINEERS/SOILS AND MATERIALS Tait Borings - Foundation Engineering and Recommendations - Inspection of Construction - Material Tasting of Sods. Concrete and Building Components u 11 76-301 Sullivan Septic Service -2- December 3, 1976 to our laboratory for verification of the field classifica- tions by a Soils Engineer. Representative samples will remain in this office for a period of 60 days to be available for your examination. The boring was probed 1/2 hour after its completion to check for the presence of groundwater. The boring was also re- checked prior to leaving the site on November 29, 1976. 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 (MDH). In accordance with these procedures, the bottom and sides of the holes were scratched with a knife blade to remove any smeared soil surfaces and to provide a natural soil interface into which the water may percolate. Two inches of coarse sand were then placed in the bottom of the holes to prevent scouring. The holes were then care- fully filled with clear water to a minimum depth of 12 inches over the top of the sand layer and allowed t soak overnight with percolation tests being conducted tK. following day. RESULTS: The Log of Soils encountered in the borings and the water level observations are shown on the attached Log of Boring sheets. The boring generally encountered lh feet of a silty clay topsoil at the surface underlain by silty clayey sand and clayey sand glacial till to approximately the 11h-foot depth. This material was in turn underlain by a fine to medium -grained glacial outwash sane: to the 14-foot depth. Glacial till clayey sand was then encountered to the 2S-foot termination depth of the boring. Silty clayey sand glacial till was the predominant soil encountered in each of the percolation tests. In probing the boring 1/2 hour after completion, groundwater was encountered at the 21-foot depth. Approximately 1h hours later the bore hole was again checked for the presence of groundwater and it was noted to be at the 20-foot depth or at an elevation of 942.0. Because of the cohesive nature of the soils encountered, considerable time required in order for the groundwater to stabilize in the boring. It does not appear that the groundwater levels were completely ORAUR" ENGINEERING TESTING 76-301 Sullivan Septic Service -3- December 3, 1976 stabilized at the time the water level checks were made. Also, based on soil borings taken by our firm throughout the project in August of this year, the possibility exists that the groundwater in this boring could possibly be in a "perched" condition. Water levels should be expected to show normal seasonal and annual fluctuations. Percolation tests indicating soil absorptivities; in minutes per inch (mpi) are as follows: Test N P-1 P-2 P-3 Surface Elevation RECOMMENDATIONS: 964.4t 958.7t M.3t Soil At Rate, Test Depth (mpi) Silty Clayey Sand (SC SM) 30 Silty Clayey Sand (SC SM) 30 Silty Clayey Sand (SC SM) 30 You have indicated that current plans call for the construc- tion of a 4-bedroom, single family dwelling on this lot. The type, size, and location of the proposed house is not known at this time. Current plans call for this dwelling to have its own individual sanitary disposal system. The lot is approximately 2 acres in size with a hill on the east side of the lot and another on the northwest side of the lot which slopes gently to the southwest towards Lake Minnetonka. The power auger boring does not provide information relative to the strength parameters of the various soil types encoun- tered, however, mineral soils of the types brought to the surface by the auger generally are of sufficient strength to support a single family dwelling without detrimental settle- ment. All three percolation tests which were conducted, generally in the east half of the lot, were all found to have a perco- lation rate of 30 mpi, which does meet the normal minimum allowable rate of 60 mpi. Based on the results of the ' percolation tests, a minimum of 300 square feet of absorptive trench per bedroom will be required on this lot. For the proposed 4-bedroom house, a minimum of 1200 square feet of BRAOR' ' ENGINEERING TESTING 76-301 ' Sullivan Septic Service -4- December 3, 1976 ' this absorptive area will be required. This requirement could be met by 600 lineal feet of 24-inch wide trenches with a 6.5-foot center to center spacing. Due to the relatively dry conditions that we have experienced this past year and based on the cohesive nature of the soils encountered, it is our opinion that the tests may ovei:stimate ' the normal permeability and thus we would recommend an addi- tional 100 square feet of area per bedroom. As shown on the attached sketch, 8 trenches, 75 feet in length are recommended. ' Also, based on the water level information obtained from the soil boring and the general topographic features of ..ae lot, we have assumed and it appears feasible that the drain field ' will be sloping in the south or southwestern direction. Based on the information obtained from the soil boring and the percolation tests taken in Lot 4, it appears the most ' logical location for the house could be either along the north half or the east half of the lot. ' GENERAL: It has been our pleasure to be of service to you on this ' project. If we can be of further assistance in evaluating these data, please contact us at your convenience. Very truly yours, UN ENGINEERING TESTING, INC. ennis M. Rie schel Engineering Assistant � �- 0 �&- zr.� C. G. KruLe, P. . Vice President - Engineering ' DMR/CGK:skf cc: City of Orono BRAUR'" ' The content of this report and supporting docurnenta are for the aagluafva use of the addraaaaa. In the absence of our prior written approval ENOINEERMIO TE8Tlld�'i we maps no representation and aasurne no reponUoufty to any other parties regarding such content. i Nu /96P QEGQESFs/T5 R9WCR A�beQ�/Nb � /2E/�C�SE/+/T'S FE�C: UG.A7'/oNi �5T •=�G�LES /Ibt': OPA/NFiELO. G'E5/6N -IgK'wA/ /S �-*_TYAiCAL L) ilewi C. i"cR 6c a /r�r 'FGi�c .ssr� Li•i- '_ ' ✓ r 10 Try CYST£ s.xf�Ti ', 76�,,;�/ tic &g, AS - n, Lor 4, 64.ccr-; / cARv/Ew Acoirl, W ENGINEERING TESTING If 12 LOG OF BORIN S ROJECT: 76-301 Soil Boring DATE: 11/29/76 Lot 4, Block 1 Fairview SCALE: 1"�4' Orono Mi nnesota t BORING: B-1 LOCATION: 99'W 6 44'N BORING: LOCAT(QN: R of S.L. property R . 962.0 corner. D*Pth Dercri ti8ii"8f" %V&iais 62487 SILTY CLAY, with a trace 1.5 of gravel, dark brown,* CL O P4 SILTY CLAYEY SAND, wit a a trace of gravel, brown SC-SM moist. (Glacial Till) u e Y a w 8 u S CLAYEY SAND, brown, 'e moist. (Glacial Till) Sc q i 11.5 g SAND, fine to medium - grained, with a trace of SE 14 gravel, brown, moist.** CLAYEY SAND, with a trace of gravel, brown, SC M 17 moist to wet. �° Till CLAYEY SAND, with a wtrace of gravel, grayish brown, wet. a (Glacial Till) v w Y 25 *frosen.(Topsoil) g **(Glacial 0utwash) Water level down 21' 1/2 hour after completion of boring. Water level down 20' 111 hours after completion of boring. ion of Amteriais DESCRIPTIVE TERMINOLOGY 1 PARTICLE SIZE IDENTIFICATION SOIL INTRUSIONS eouldsrs over 3.. THICKNESS RELATIVE /ROPORTIONa ' Gar veal isrkss 0 — Ile" with a hw 0 — ; 0% Corso 1" — 3" sum Ile" — 1" with soma 11 — 20% Madum 1il" — 1" low 1" — 12" with over 20% Fins No. 4 — 1R" wowed alternating norm or SrkO hmm of clays and Oeaea No. 4 — No.10 silts In lake deP Mecum No,10 — No. 4 FMta No.40 — No. ;*." MOISTURE CONTENT ORGANIC CONTENT ' Vmv FMr No. 100 — No. 200 Sat No. 200 — =5 mm Dry kte then 5% 0 — a% non to slightly organi _ aw Nate then AM mm Mokt under optimum moisture 6 — 10% slightly organic ' Wet war optimum moisture 11 — 25% organic: 106terburing saturated sand 26 — 05% muck 6%* put ' RI" rE DENSITY OF CONSISTENCY OF PLASTICITY OF SOILS WITH CL ._arfONLESS SOIL= COHESIVE SOILS LESS THAN 20% CLAY very home 0 — 4 aPF very soh 0 — 1 BFF non plastic gritty, cannot thread ' kioaa 5 — 10 OPP soh 2 — 3 6PF slightly plastic rough to to ooth, «atsil an dares 11 — 30 OFF rather soft 4— 5 ePF herd to thread devise 31 — 50 OPP meduen 6 — S ePF piratic smooth to waxy, vary dmw 50+ aPF retfur soft e — 12 ePF easy to thread stiff 13 — 16 OPP very ad" 17 — 30 a" herd 30+ OPP RELATIVE PROPORnm OF GRAVEL LABORATORY TESTS • tastes 0 — e% DD Dry Dansihr, pd OC Orgenk Content. % . Nt11e 6 —16% wD Wet OwIty, pd a Prortt of Seturation. % oaths 16 — 30% Mc No m Mokiara Content. % aG Spae+fk Gravity w 31 —a0% LL Liquld LirNt. % C Colteelen PL no Limit, % 6 Angle of Internal Frietkn PI Plasticity Index. % vu Unimenfkied Corrkpreteiwe Strength DRILLING NOTES: Standard penetration ant boring; were sdrwoad by 216" or 3%" I.D. hollowrssem augers unless woad othn- wise..letting water vrea used to cash out auger prior " srnpling only where indi—ted on lop. Standard pensastion tat borings are dn*mmd by the prefix "sT" (split Tube). Power auger boring were advanced by 4" or 6" dienrm, cantirwous4lia. solid stem augers. Soil alessifiestion ' and strata depths are 6nfare0 from disturbed aemples augered to the surface and are therefore somewhat epproximess. Power auger borinp are designated by the prefix "e". Hend p►obinp were sdvenced memrelly with a 1 %" diameter probe end we limited to the depth from which the Probe cm to im me IV withdramm. Hand probing ere k"mmed by the prefix "H". ' CLASSIFlt4% AON: CledAcetion on legs Is mob by inspection in soccer' - with the Unified Soik Cktteifkstion ayssun lsea attached dot) using vieuai4na+usl procedures unless noted otherwise. OROIMD NArtER: Observadons were nude at the time; Indirarted. Pm cmitV of soil strate, saasacel weather oondltiona. site ' sspagrephy, ate., mey asute dtrgse In the wasr Isvds Indioeaed on the lop. SAMPLING: AN err I are taken with the standard 2" O. D. split•tube ampiar, axoapt where nosed. TW indketw thin - won a disk"" ses"Ple. WF: Nwrbn Irtel1 blows per foot reoadad in stutdeed penati on test, also known as "N" wake. The onpsr is set 6" Into undisturbed soil below the hollow -stem auger. Driving resistances we than counted for teea�d and third 6" in crerrnnts and added to pt 6PF. Where they differ significantly, they are reported in the ' following form — 2112 for the saoon'and third 6" inraemants respectively. NH: W4 indicates the aantpla penetrated soil under weight of harmer and rods alorr, driving not required. ' NOTE: All Poste run in smardsnoe with appRemble ASTM standrds. ENGINEERING TESTING u u 11 UNIFIED SYSTEM CLASSIFICATION OF SOILS FOR ENGINEERING PURPOSES ASTM DESIGNATION D-2487 Maj-pr Divisions N U �o zCC W O d 0 ti LV '0 SAN Group Symbols Typical Names Well -graded gravels and ow gravel -sand mixtures, little or no fines Poorly graded gravels and op ravel -sand mixtures, little or no fines Sil gravels gravel - GM sansitt mlxiures Clayey gravel! •avel- OC sand -clay mlxLures Well -graded sands and sr gravelly sands, little or no fines -?oriy graded sands and gravelly sands, little or no fines Silty sands, sand -silt sM mixtures so Clayey sands, sand -clay mi xtures Inorganic silts, rock flour, silty or clayey AIL fine sand Classification Criteria Cu - De0 / DIG Greater than 4 Cs D102 DSO Between 1 and 3 a+ N Not neeLing both criteria for ow o N � y v " Atte►bery'limrfts plot below "A" line -it, Atterberg limits plot- , . I plasticity index ting in hatched area a less than 4 _ffierberg are borderline b,�• t limits plot "A" classifications re - above line and quiring use of dual plasticity index symbols c l i 4 C lei greater than 1 �► _ Cu - D60I D10 Greater than 6 m N CX - (D an12 Between 1 and 3 Q 8 N D10 %De0 1 N 5 Not meeting both criteria for sY i $ on �>g Atterberg limits plot Below "An line or Atterberg liwAts plot- d plasticity index less than 4 ting in hatched area borderline �- are clas- Atterbery li ts plot "A line sifications requiring above and use of symbols plasticit index greater t�ian 1 Inorganic clays 0 Ow 0 sodium plasticity. yrav- lz elly clays, sandy clays. 60 tioiiw For ettassifi ct, of fine- _ silty clays. lean clays 50 grained eoite and ii• Mottos Organi c silts and organic Of oome-ruined •otts• Atterberg tiwite OL silty clays of low 40 ptotting in hatehed arm my borderline — plasticity o' ,ifioastort. regatrinp Inorganic silts, micaceous iP 30 we. of drat eMtbota. a�watton of A-t Aff or diatomaceous silts, 1 pi- o.?a rrc-:o elastic silts 20 _ — Inorganic clays of high C9 plasticity. fat clays 1 Organic clays of ndi umi CH to high plasticity M 0 0 10 20 30 40 50 60 10 Uquid Unit organic soils pt hat. muck and othor gh y orgainic so.i& Visual -manual identification BRAUR" ENGINEERING TESTING top An Expansion of Soil Engineering Services, Inc. BRAUR" EMNEERING TMNG ■INNI MUS/BT. PAUL MS. CNNNh N.1 B. P.O. Box ri1N. MNs.. Me. IMU 1612.141-NOB NONTNINN 010NUOTA 3211 L IMIt knove. NNtial. Me. 617161118-2O3-BN1 January 7, 1977 Sullivan Septic Service 7660 Highway 101 South Wayzata, MN 55391 Attn: Mr. Ed Sullivan Gentlemen: J. E. EaAYN �. E., Nribnt f.N. ANOE=, 1Rw pow Aereeia� CO. EatNE F. E. Via Am EneaNwiq 0. R *O"NM I.E. like Am TweYr Re: 76-301 SOTT. n^RING & PERCOLATION L._ . ►3lock 1 Fairview Addition Orono, Minnesota As requested by you, we have attached a suitable design for a sewage disposal system, for the above referenced lot as described in our soil boring and percolation test report, dated December 3, 1976. The system shown contains 12 disposal lines, 50 feet in length, connected in a series for a total of 600 lineal feet, as recommended in our report dated December 3, 1976. This system design is based on an assumed t.:sement floor elevation of r95" feet. If we can be of further assistance in evaluating these data, please contact us at your convenience. Very truly yours, jry NGINEERING TESTING, INC. son Engie ring Assistant GLN/skf CONSULTING ENGINEERS/SOILS AND MATERIALS Test Borings - Foundation Engineering and Recommendations • Inspection of Construction - Material Tesbnp of Soft. Concrete and Budding Components / Existl;10 E+�d 'E�aunCvi' FcoaR EAS956.0 At\a 6CA V14 ;w 'p I A .5 -Srem 40'ril.e q�islS-�b�j�on Uns gxf roocr.:gn;- IAWM m-76-330/�SEN146E 0151-V Lr-,, L.or 4, eL cc k FA 1,qv1Ew Aoo1riokj ENGINEERING TESTIt:r; I -' "IMA1. • [eu: 117176 Mviud: Draw: �aL/!I Snls: /, 71 _ E COMBS-KNUTSON ASSOCIATES, INC. CONSULTING ENGINEERS N LANG SURVEYORS ■ SITE PLANNERS January 12, 1977 Mr. Al Olson City of Orono P.O. Box 66 Crystal Bay, MN 55323 Subject: Septic System Review Lot 4, Block 1, Fairview Addition Dear Al: We have reviewed the subject septic system application and offer the following comments: 1. Two check valves should be installed on the discharge line of the lift pump. 2. A back water valve should be installed on the gravity flow line from the house to the lift pump structure. 3. All septic tanks should be constructed in accordance with Orono's regulations. Providing that the above items are met, we recommend approval of the system as submitted. GF:sw ENROWE 2333 M JAN 1:3 19l1 D� 1. 4'171/ Very truly yours, McC S-KNUTSON ASSOCIATES, INC. G g rank, P.E. 12805 OLSON MEMOPIAL HIGHWAY, MINNEAPOLIS, MINNESOTA 55441 TELEPHONE (612) 559-3700 36 NORTH MAIN STREET, HUTCHINSON, MINNESOTA 55350 TELEPHONE (612) 879-8029 SOUTHWEST ENGINEERING DIVISION, MARSHALL, MINNESOTA 56258 TELEPHONE (507) 532-5820 io �O 6:werhtibw 426 AA AM am ! . •r� AM or 440, 1 14 . i k. / to, •b � � ; V 1 •' ' Vim-- 4 v-10 ` i t . 7 -301 SEW,46E OISPOMI- SYSre M L.nT C