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2241 Wall St - Soil Summary for Proposed 3-Season PorchHAUGD June 28, 2021 Mike and Linda Koehler 2241 Wall S gan, MN 55122 HGTS Project Number: 21-0632 Re: Soil Summary, Proposed 3 Season Porch, 2241 Wall Street, Eagan, Minnesota Dear Mr. Mike and Ms. Linda Koehler; We have completed the soil borings at the above referenced address in Eagan, Minnesota. This letter provides a summary of our procedures and the results obtained. Our services were performed as authorized by you and in accordance with the Haugo GeoTechnical Services proposal 21-0632 dated May 26, 2021. Project Description Mike and Linda Koehler are preparing to complete the construction of a 3-season porch at their residence at 2241 Wall Street in Eagan, Minnesota. We understand that the home was constructed about 4 to 5 years ago which also included constructing/installing the piers/foundations for the 3- season porch however, construction of the porch was not completed at that time. Mike and Linda Koehler retained Welter Construction to complete construction of the porch and submitted plans to the City of Eagan (City) for review and permitting. Prior to issuing construction permits the City and the project structural engineer required that a qualified geotechnical engineering firm evaluate the soils and provide a soil bearing capacity. We understand that results of the geotechnical evaluation will then be used to verify that the existing footings are adequately sized. Welter Construction on behalf of Mike and Linda Koehler retained Haugo Geotechnical Services to perform the requested/required geotechnical exploration. Documents Provided To aid in our evaluation, we were provided a 6-page porch/ deck structural plan set that was dated April 26, 2021 and prepared by Linderman Engineering & Consulting. The plan set included the following pages: Elevations, Elevation/Footing Plan, Floor/Deck Framing Plan, Roofing/Section Plan and Sections. Based on a brief review of the plans we understand that piers/footing for the porch bear about 42 inched below exterior grades. Locations and Elevations The soil boring locations were selected by Welter Construction based on the location of the existing porch footings. The approximate locations of the soil borings are shown on Figure 1, "Soil Boring Location Sketch," in the Appendix. The sketch was prepared by HGTS using an aerial image from Google Earth as a base. Page 12 HGTS obtained the ground surface elevations at the soil boring locations using GPS technology based on the MN County Coordinate System (Dakota County). GPS coordinates and ground surface elevations are provided on Figure 1 in the Appendix. HGTS does not practice in land surveying therefore, the ground surface elevations presented on the boring logs should be considered approximate. Procedures The project site was not accessible to our drill rig and because of that two (2) hand auger borings and two (2) Dynamic Cone Penetrometer (DCP) tests were performed. The DCP tests and hand auger borings were performed by HGTS on June 8, 2021. The DCP consists of a solid metal rod fitted with a 15/s-inch diameter conical point. The point is driven into the soil with a 10-pound weight falling 24 inches. The number of blows required to drive the point each 6-inch increment was used to estimate the soils' consistency or relative density. The hand auger borings were performed using a 4-inch diameter bucket style hand auger. The hand auger was advanced in 3 to 6-inch increments to depths ranging from about 31/2 to 61/2 feet below the ground surface. The hand auger was then withdrawn to obtain cuttings which were classified in general accordance with ASTM 2488, "Description and Identification of Soils (Visual/Manual Procedures)". A field log of each boring was prepared by HGTS. The logs contain visual classifications of the soil materials encountered during drilling, as well as the driller's interpretation of the subsurface conditions between samples and water observation notes. The final boring logs included with this report represent an interpretation of the field logs and include modifications based on visual/manual method observation of the samples. The strata changes were inferred from the changes in the samples and auger cuttings. The depths shown as changes between strata are only approximate. The changes are likely transitions, variations can occur beyond the location of the boring. Soil boring logs identifying and describing the soil materials encountered in the hand auger borings are attached. General terminology for soil description and identification, and classification of soils for engineering purposes are also attached. Results Soil Conditions It should be noted that the area around the footings had been excavated prior to our exploration; therefore, HAP-1 started at a depth of about 8 inches below the ground surface (bgs) and HAP-2 was started at a depth of about 28 inches bgs. The hand auger borings encountered clayey soils consisting of clayey sand, sandy lean clay and lean clay that extended to the termination depths of borings at nominal depths of about 3 1/2 to 6 1 feet below the ground surface. HAP-1 encountered about 1/2 foot of gravel at a depth of about 3 feet below the ground surface. DCP tests were performed at each of the hand auger boring locations. The DCP results within the soils showed blow counts ranging from 3 to over 50 blows per 6-inch increment, with most of the values 2825 Cedar Avenue S, Minneapolis, MN 55407 Page 13 between 6 and 30 blows per 6-inch increment. These values indicate the soils had a medium to stiff consistency. The higher blow counts (50 blows per 6-inch increment) represent practical refusal. Groundwater Conditions Groundwater was not encountered in the hand auger borings. Groundwater appears to be below the depths explored by our borings. Water levels were measured on the dates as noted on the boring logs and the period of water level observations was relatively short. It is possible that insufficient time was available for groundwater to seep into the borings and rise to its hydrostatic level. Groundwater monitoring wells or piezometers would be required to more accurately determine water levels. Seasonal and annual fluctuations in the groundwater levels should be expected. Conclusion Based on the results of our observations and tests, it is our opinion that the on -site soils are suitable for porch foundation support. It is further our opinion that a soil bearing pressure of 2,000 pounds per square foot (psf) can be used to verify footing sizes and/or redesign the porch foundations. General Soil borings with powered equipment (i.e., drill rig) were not performed for this exploration. Because of that the exploration depths were limited and soils information below a depth of about 6 1/2 feet is unknown. The analyses and recommendations presented in this report are based on data obtained from a limited number of soil borings. Variations can occur away from the borings, the nature of which may not become apparent until additional exploration work is completed, or construction is conducted. A reevaluation of the recommendations in this report should be made after performing on -site observations during construction to note the characteristics of any variations. The variations may result in additional construction costs and it is suggested that a contingency be provided for this purpose. We made water level measurements in the soil borings at the times and under the conditions stated on the boring logs. The data was interpreted in the text of this report. The period of observation was relatively short and fluctuations in the groundwater level may occur due to rainfall, flooding, irrigation, spring thaw, drainage, and other seasonal and annual factors not evident at the time the observations were made. Design drawings and specifications and construction planning should recognize the possibility of fluctuations. Haugo GeoTechnical Services has used the degree of skill and care ordinarily exercised under similar circumstance by members of the profession currently practicing in this locality. No warranty expressed or implied is made. 2825 Cedar Avenue S, Minneapolis, MN 55407 Page 14 Thank you for the opportunity to assist you on this project. If you have any questions or need additional information, please contact Lucas Mol or Paul Gionfriddo at 612-729-2959. Sincerely, HAUGO GEOTECHNICAL SERVICES Lucas Mol Project Manager I hereby certify that this plan, specification, or report was prepared by me or under my direct supervision and that I am a duly Registered Professional Engineer under the laws of the State of Minnesota. Paul Gionfriddo, P.E. Senior Engineer License Number 23093 Attachments: Soil Boring Location Sketch Soil Boring Logs; HAP-1 and HAP-2 DCP Results Descriptive Terminology 2825 Cedar Avenue S, Minneapolis, MN 55407 Legend SApproximate Soil Boring Location GPS Boring Locations Boring Number Elevation (Feet) Northing Coordinate Easting Coordinate HAP-1 948.5 211979.334 523807.599 HAP-2 948.4 211984.098 523812.698 Referencing Minnesota County Coordinates Basis — Dakota County Disclaimer: Map and parcel data are believed to be accurate, but accuracy is not guaranteed. This is not a legal document and should not be substituted for a title search, appraisal, survey, or for zoning verification. Haugo GeoTechnical Services, LLC 2825 Cedar Avenue S. Minneapolis, MN 55407 Soil Boring Location Sketch 2241 Wall Street Eagan, Minnesota Figure #: 1 Drawn By: NA Date: 6/23/2021 Scale: None Project #: 21-0632 HAUGO SERVICES Haugo GeoTechnical Services 2825 Cedar Ave South Minneapolis, MN 55407 Telephone: 612-729-2959 Fax: 763-445-2238 BORING NUMBER HAP-1 PAGE 1 OF 1 CLIENT Welter Construction PROJECT NAME 2241 Wall Street PROJECT NUMBER 21-0632 PROJECT LOCATION St. Paul, MN DATE STARTED 6/8/21 COMPLETED 6/8/21 GROUND ELEVATION 948.5 ft HOLE SIZE 3 1/4 inches DRILLING CONTRACTOR HGTS GROUND WATER LEVELS: DRILLING METHOD Hand Auger AT TIME OF DRILLING --- Not Encountered LOGGED BY NA CHECKED BY PG AT END OF DRILLING --- NOTES Hand Auger met refusal at 3.5 Feet AFTER DRILLING -- Not Encountered d O 0.0 O 20 a-0 O MATERIAL DESCRIPTION w CL Hw LU CO Jg o- D Qz 0) w 1- 0 z ♦ SPT N VALUE • 20 40 60 80 PL MC LL • 20 40 60 80 ❑ FINES CONTENT (%) ❑ 20 40 60 80 2.5 Open hole to a depth of about 8 inches AU (CL) Sandy Lean Clay, trace Gravel, brown, wet. (GP) Gravel. (CL) Sand Lean Clay, Landscape Fabric, brown, wet. AU AU AU Bottom of borehole at 3.7 feet. Haugo GeoTechnical Services BORING NUMBER HAP-2 HAUGO 2825 Cedar Ave South PAGE 1 OF 1 ■ • • : Minneapolis, MN 55407 SERVICES Telephone: 612-729-2959 Fax: 763-445-2238 CLIENT Welter Construction PROJECT NAME 2241 Wall Street PROJECT NUMBER 21-0632 PROJECT LOCATION St. Paul, MN DATE STARTED 6/8/21 COMPLETED 6/8/21 GROUND ELEVATION 948.3 ft HOLE SIZE 3 1/4 inches DRILLING CONTRACTOR HGTS GROUND WATER LEVELS: DRILLING METHOD Hand Auger AT TIME OF DRILLING -- Not Encountered LOGGED BY NA CHECKED BY PG AT END OF DRILLING --- NOTES Hand Auger met refusal at 6.5 Feet AFTER DRILLING --- Not Encountered o DEPTH o (ft) GRAPHIC LOG MATERIAL DESCRIPTION SAMPLE TYPE NUMBER RECOVERY % (RQD) BLOW COUNTS (N VALUE) MOISTURE CONT. (%) NOTES A SPT N VALUE • 20 40 60 80 PL LL 20 40 60 80 0 FINES CONTENT (%) 0 20 40 60 80 2 5 Open Hole to a depth of about 28 inches AU ! / (CL) Sandy Lean Clay, with Gravel, brown, wet. AU _ 5.0 (SC) Clayey Sand, brown, moist. 1 (CL) Lean Clay, brown, moist. AU Bottom of borehole at 6.3 feet. Job Number: 21-0632 Date: 6/8/2021 Technician: NA Dynamic Cone Penetrometer Tests DCP #1 DCP #2 DCP #3 Elevation (ground surface) 948.5 feet 948.4 feet 0' - 0.5' 12 3 0.5' - 1' 13 20 1' - 1.5' 7 7 1.5' - 2' 6 25 2' - 2.5' 11 14 2.5' - 3' 13 16 3'-3.5' 50 for 3" 23 3.5' - 4' 30 4'-4.5' 50 for 5" 4.5' - 5' 5' - 5.5' 5.5' - 6' 6' - 6.5' 6.5' - 7' 7' - 7.5' 7.5' - 8' 8' - 8.5' 8.5' - 9' 9' - 9.5' 9.5' - 10' 10' - 10.5' 10.5' - 11' 11' - 11.5' 11.5' - 12' Locations Center Footing NE Corner Footing HAUGD • SERVICES Descriptive Terminology of Soil Standard D 2487 - 00 Classification of Soils for Engineering Purposes (Unified Soil Classification System) Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests 2 Soils Classification Group Symbol Group Name b Coarse•grained Soils more than 50% retained on No. 200 sieve Gravels More than 50% of coarse. fraction retained on No. 4 sieve Clean Gravels 5% or less fines ° C. > 4 and 1._ Ce S 3 ` J GW Weil -graded gravel° C.< 4 and/or 1 > C.> 3 c GP Poorly graded gravel' Gravels with Fines More than 12% fines a Fines classify as ML or MH GM Silty gravel ° r9 Fines classify as CL or CH GC Clayey gravel d rg Sands 50% or more of coarse fraction passes No. 4 sieve Clean Sands 5% or less fines ' C. > 6 and 1 < C. 5_3 ` SW Weil -graded sand " C < 6 and/or 1 > Cc> 3 ° SP Poorly graded sand ^ Sands with Fines + More than 12% t Fines classify as ML or MH SM Silty sand r9" Fines classify as CL or CH SC Clayey sand Fine-grained Soils 50% or more passed the No. 200 sieve Silts and Clays Liquid limit less than 50 Inorganic g PI > 7 and plots on or above "A' line I CL lean clay " PI < 4 or plots below "A" liner ML Silt k ' ", Organic Liquid limit - oven dried < 0.75 OL OL Organic clay' ' "' Organic silt k ' m ` Liquid limit - not dried Silts and clays Liquid limit 50 or more Inorganic PI plots on or above "A" line CH Fat clay k' ' PI plots below "A" line MH Elastic silt "' '^ Organic Liquid limit - oven dried OH OH Organic clay "' " ° Organic silt "' ' ❑ < 0.75 Liquid limit - not dried Highly Organic Solis Primarily organic matter, dark in color and organic odor PT Peat a Based on the material passing the 3-in (75mm) sieve. b. If field sample contained cobbles or boulders, or both. add 'with cobbles or boulders or both" to group name. a Cv = 0 / D,0 C _ (D30)2 D1C x D� d e k m. n. o. p q Plasticity Index (PI) If soil contains>15% sand add'wi h sand" to group name. Gravels with 5 to 12% fines require dual symbols: GW-GM well -graded gravel with silt GW-GC well -graded gravel with clay GP -GM poorly graded gravel with silt GP -GC poorly graded gravel with'Gay If fines classify as CL-ML, use dual symbol GC -GM or SC-SM. If fines are organic. add "with organic fines- to group name. If soil contains 2 15% gravel. add 'with graver to group name. Sands with 5 to 12% fines require dual symbols: SW-SM well -graded sand with silt SW -SC well -graded sand with clay SP-SM poorly graded sand wdh sits SP-SC poorly graded send with clay lt Atterberg limits plot in hatched area. soil is a CL-ML. city tray. It soil contains 10 to 25 % plus No. 200, add 'with sand' or "with graver whichever Is predominant. If soil contains Z 30% plus No. 200. predominantly sand. add "sandy' tc group name If soil contains 2 30% plus No. 200 predominantly grave/add 'gravelly' to group name. PI 2 4 and plots on or above'A" line. PI <4 or plots below "A' line. PI plots on or above "A" line. PI plots below 'A' line. 60 50 40 30 20 10 7 4 0 DO WD MC LL PL PI P200 ♦ G / ' / e &' /' / / G>' oc MHorOH ML or OL ////cL- C7 10 16 20 30 40 50 60 Liquid Limit (LL) Laboratory Tests Dry density, pcf Wet density. pcf Natural moisture content, Liqiuid limit. % Plastic limit. % Plasticity index. % % passing 200 sieve o� OC S SG C 0 qu qp 70 80 90 100 Organic content. Percent of saturation. % Specific gravity Cohesion, psf Angle of internal friction Unconfined compressive strength. psf Pocket penetrometer strength, tsf 110 Particle Size Identification Boulders over 12" Cobbles 3' to 12" Gravel Coarse 3/4' to 3' Fine No. 4 to 3/4' Sand Coarse No. 4 to No. 10 Medium No. 10 to No. 40 Fine No. 40 to No. 200 Silt <No. 200, PI < 4 or below "A" line Clay <No. 200, PI Z 4 and on or above "A" line Relative Density of Cohesionless Soils Very loose 0 to 4 BPF Loose 5 to 10 BPF Medium dense 11 to 30 BPF Dense 31 to 50 BPF Very dense over 50 BPF Consistency of Cohesive Soils Very soft 0 to 1 BPF Soft 2 to 3 BPF Rather soft 4 to 5 BPF Medium 6 to 8 BPF Rather stiff 9 to 12 BPF Stiff 13 to 16 BPF Very stiff 17 to 30 BPF Hard over 30 BPF Drilling Notes Standard penetration test borings were advanced by 3 1/4" or 6 1 /4" ID hollow -stem augers unless noted otherwise, Jetting water was used to clean out auger prior to sampling only where indicated on logs. Standard penetration test borings are designated by the prefix 'ST' (Split Tube). All samples were taken with the standard 2' OD split -tube sampler, except where noted. Power auger borings were advanced by 4' or 6" diameter continuous - flight, solid -stem augers. Soil classifications and strata depths were in- ferred from disturbed samples augered to the surface and are, therefore, somewhat approximate. Power auger borings are designated by the prefix "B." Hand auger borings were advanced manually with a 1 1/2' or 3 1/4" diameter auger and were limited to the depth from which the auger could be manually withdrawn. Hand auger borings are indicated by the prefix BPF: Numbers indicate blows per foot recorded in standard penetration test. also known as "N' value. The sampler was set 6" into undisturbed soil below the hollow -stem auger. Driving resistances were then counted for second and third 6" increments and added to get BPF. Where they differed significantly, they are reported in the following form: 2/12 for the second and third 6" increments, respectively. WH: WH indicates the sampler penetrated soil under weight of hammer and rods alone; driving not required. WR: WR indicates the sampler penetrated soil under weight of rods alone: hammer weight and driving not required. TW indicates thin -walled (undisturbed) tube sample. Note: All tests were run in general accordance with applicable ASTM standards. Rev 7107