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3 Table of Contents Description Page A. Introduction... 1 A.1. Project Description... 1 A.2. Purpose... 1 A.3. Background Information and Reference Documents... 1 A.4. Site Conditions... 1 A.. Scope of Services... 2 B. Results... 3 B.1. Exploration Logs... 3 B.1.a. Log of Boring Sheets... 3 B.1.b. Geologic Origins... 3 B.2. Geologic Profile... 4 B.2.a. Materials Encountered... 4 B.2.b. Groundwater... B.3. Laboratory Test Results... B.4. Ground Penetrating Radar... B.. Falling Weight Deflectometer... 6 B..a. Calculated R-values... 6 B..b. Calculated Granular Equivalent... 7 C. Discussion... 9 C.1. Design Details... 9 C.1.a. Expected Traffic and Pavement Type... 9 C.1.b. Anticipated Grade Changes... 9 C.1.c. Precautions Regarding Changed Information... 9 C.2. Design and Construction Considerations... 1 C.2.a. Visual Assessment of Pavement Surface Condition... 1 C.2.b. Pavement Repair... 1 D. Recommendations D.1. Pavements D.1.a. Design R-value D.1.b. Materials and Compaction D.2. Construction Quality Control D.2.a. Excavation Observations for Subcuts D.2.b. Materials Testing D.2.c. Cold Weather Precautions E. Procedures E.1. Penetration Test Borings E.2. Material Classification and Testing E.2.a. Visual and Manual Classification... 13

4 Table of Contents (continued) Description Page E.2.b. Laboratory Testing E.3. Groundwater Measurements E.4. Ground Penetrating Radar E.4.a. Data Collection E.4.b. Analysis E.. Falling Weight Deflectometer... E..a. Testing... E..b. Analysis... F. Qualifications F.1. Variations in Subsurface Conditions F.1.a. Material Strata F.1.b. Groundwater Levels F.2. Continuity of Professional Responsibility F.2.a. Plan Review F.2.b. Construction Observations and Testing F.3. Use of Report F.4. Standard of Care Appendix Soil Boring Location Sketch Log of Boring Sheets (ST-13 through ST-18) Descriptive Terminology GPR Results Tabular FWD Results

5 A. Introduction A.1. Project Description This Geotechnical and Pavement Evaluation Report addresses the existing conditions of CSAH (Stonebridge Trail N), from TH 96 (Dellwood Rd.) to CSAH 11 (Otchipwe Ave. N). The segment is approximately 1.8 miles in length. We understand that CSAH is scheduled for rehabilitation in 216. Based on the information provided, we understand that the likely repair option will include Stabilized Full Depth Recycling (SFDR) followed by an overlay. A.2. Purpose The purpose of the geotechnical and pavement evaluation was to provide information and recommendations, including in-place pavement thicknesses, subgrade soil classification, and in-situ R- values calculated from previously collected Falling Weight Deflectometer (FWD) testing, in order to assist Washington County in the rehabilitation of CSAH. A.3. Background Information and Reference Documents To facilitate our evaluation, we were provided with or reviewed the following information or documents: Aerial photographs available from Google Earth. Washington County Geologic Atlas from the Minnesota Geological Survey. Pavement history information available from the County. FWD test data for the segment available from the County. A.4. Site Conditions Our referenced documents and past project experience in the general area indicate that the roadway is underlain mostly with outwash deposits. CSAH is a two-lane, two-way bituminous rural roadway. The roadway topography is rolling with elevations rising from south to north. Annual average daily traffic (AADT) from 211 is 3,, and from 212 is 3, vehicles per day, according to the County.

6 Washington County Public Works Revised Project B733. November 4, 2 Page 2 Previously available maintenance and construction history for this roadway shows the following: 2 inches wearing course (1997) 1 1/2 inches SPEC 2341 wearing course (1987) Variable depth SPEC 2331 leveling course (1987) Variable depth Class 2 aggregate shouldering (1987) 1 1/2 inches SPEC 2321 bituminous base (1964) inches Class gravel base (1964) Original grading (19) A.. Scope of Services Our scope of services for this project was originally submitted as a Proposal to Mr. Andrew Giesen of Washington County Public Works. We received authorization to proceed by receipt of a signed contract. Tasks performed in accordance with our authorized scope of services included: Staking and clearing exploration locations of underground utilities. Scanning the roadway with a 2.-gigahertz, air-coupled Ground Penetrating Radar (GPR) in both directions of travel under the direction of an Engineer. Performing six (6) standard penetration test borings within the roadbed to feet below the existing pavement surface. Providing appropriate traffic control during the field operations. Performing analysis of previously collected FWD data to obtain estimates of subgrade R- value and effective in-situ granular equivalency (GE) values, as well as identify potential boring locations. Performing up to seven (7) moisture content tests and two (2) mechanical analysis (through a #2 sieve only) on select soil samples.

7 Washington County Public Works Revised Project B733. November 4, 2 Page 3 Preparing this report containing a boring location sketch, exploration logs, summary of the geologic materials encountered, results of GPR and FWD testing, and a discussion of the results with regard to various rehabilitation options for the roadway. Exploration locations and surface elevations at the exploration locations were determined using GPS technology that utilizes the Minnesota Department of Transportation's (MnDOT) permanent GPS Virtual Reference Network (VRN). Our scope of services was performed under the terms of Contract Number 9772 with Washington County. B. Results B.1. Exploration Logs B.1.a. Log of Boring Sheets Log of Boring sheets for our penetration test borings are included in the Appendix. The logs identify and describe the geologic materials that were penetrated, and present the results of penetration resistance and laboratory tests performed on penetration test samples retrieved from them, and groundwater measurements. The sampling rate performed consisted of a 2 1/2-foot sampling interval to the depth of termination. Strata boundaries were inferred from changes in the auger cuttings. The boundary depths likely vary away from the boring locations, and the boundaries themselves may also occur as gradual rather than abrupt transitions. B.1.b. Geologic Origins Geologic origins assigned to the materials shown on the logs and referenced within this report were based on: (1) a review of the background information and reference documents cited above, (2) visual classification of the various geologic material samples retrieved during the course of our subsurface exploration, (3) penetration resistance and other in-situ testing performed for the project, (4) laboratory test results, and () available common knowledge of the geologic processes and environments that have impacted the site and surrounding area in the past.

8 Washington County Public Works Revised Project B733. November 4, 2 Page 4 B.2. Geologic Profile B.2.a. Materials Encountered The general geologic profile at the site consists (proceeding down from the ground surface) of bituminous pavement and aggregate base over soils including silty sand, clayey sand, silty clayey sand, and poorly graded sand. Clayey sand or poorly graded sand were the most common subgrade types, extending to the -foot termination depth of borings. Table 1 shows the pavement thickness measurements made by the drillers in the field. The thicknesses are generally greater than those obtained from the GPR. It should be noted that for the purpose of in place thickness measurements, coring usually leads to more reliable results. Table 1. Pavement Material Thicknesses Measured Thicknesses (inches) Boring Bituminous Aggregate Base* Total ST / /4 ST / /2 ST- 8 1/2 6 1/2 ST /2 6 1/2 ST ST Average * Aggregate base was identified by drillers in the field. Laboratory tests to determine a classification (i.e. Class ) of the aggregate base were not performed. It appears that the measured bituminous and aggregate base thicknesses are similar to those indicated by the pavement history for borings ST-13 through ST-14 (TH 96 to Oak Green Ave.). For the northern segment (Oak Green Ave. to CSAH 11), borings showed a significantly greater average thickness than shown by the pavement history.

9 Washington County Public Works Revised Project B733. November 4, 2 Page B.2.b. Groundwater Groundwater was not observed as our borings were advanced. Based on the moisture contents of the geologic materials encountered, it appears that groundwater was below the depths explored at the time of our exploration. Seasonal and annual fluctuations of groundwater, however, should be anticipated. B.3. Laboratory Test Results Results of our laboratory tests are presented below in Table 2. Table 2. Laboratory Test Results Sample Depth Moisture Content Percent Passing Boring (feet) (%) #2 Sieve Soil Classification ST Silty clayey sand (SM-SC) ST Poorly graded sand (SP) ST Silty sand (SM) ST Poorly graded sand (SP) ST Clayey Sand (SC) ST Clayey Sand (SC) ST Poorly graded sand (SP) With the exception of ST-18, the moisture content results indicate the soils were likely below their optimum moisture contents for compaction in general. B.4. Ground Penetrating Radar We estimated pavement thicknesses from the GPR scans as shown in Table 3. See the Appendix of this report for a plot showing GPR-measured thickness by station.

10 Washington County Public Works Revised Project B733. November 4, 2 Page 6 Table 3. GPR-Measured Thicknesses GPR Layer Thicknesses (inches) Bituminous* Aggregate Base Average th Percentile. --- th Percentile *Average of the two lanes data. Due to ambient noise and interference weakening the GPR signal, the aggregate base layer was very difficult to identify in many places and has not been included above. Where aggregate base layer was clearly identified in the scan, it was shown on the GPR results which can be found in the Appendix. Given the bituminous layer results, the thicknesses generally seem to be slightly thinner than those obtained by borings and slightly thicker than the available information from project history. We have utilized the GPR data in considering strategies appropriate for CSAH. B.. Falling Weight Deflectometer FWD testing was completed as described in section E. of this report. Test-by-test plots of the data presented below can be found in the Appendix. B..a. Calculated R-values The FWD-calculated R-value results are presented in Figures 1 and Tables 4.

11 R-Value Washington County Public Works Revised Project B733. November 4, 2 Page Test Station from TH 96 (mile) Figure 1. FWD-calculated R-value (TH 96 to CSAH 11) Table 4. FWD-based R-value Results (TH 96 to CSAH 11) Effective Subgrade R-value Average 19.4 Standard Deviation 4.9 Minimum 11.6 Maximum 32.1 th Percentile 14.6 The subgrade trends slightly weaker from south to north. B..b. Calculated Granular Equivalent The FWD-derived granular equivalent (GE) is presented in Figure 2 and Tables.

12 Granular Equivalent (GE) Washington County Public Works Revised Project B733. November 4, 2 Page Test Station from TH 96 (mile) Figure 2. FWD-calculated Granular Equivalent (TH 96 to CSAH 11) Table. Effective GE Results (TH 96 to CSAH 11) Effective GE (inches) from FWD Data Average 26 Standard Deviation 3.9 Minimum 18 Maximum 33.2 th Percentile 21.2 All else equal, higher R-values, as determined from FWD testing will reduce the apparent contribution to structure attributed to the upper pavement layers. Conversely, R-values from FWD testing will tend to be conservative relative to laboratory values, resulting in greater attribution of overall stiffness to the upper layers in the form of GE. For CSAH, the R-value appears to reasonably represent the pavement based on our knowledge of pavement thicknesses, material and surface conditions and soil types.

13 Washington County Public Works Revised Project B733. November 4, 2 Page 9 C. Discussion C.1. Design Details C.1.a. Expected Traffic and Pavement Type Based on the previously cited traffic counts and using the State Aid ESAL Traffic Forecast Calculator, approximately 1,98, equivalent single axle loads (ESALs) should be expected for the 2-year bituminous design for CSAH (assumptions included a rural traffic distribution). Formal pavement thickness design is to be completed by the County; using MnDOT s FlexPave program, we estimate the GE requirement for a 2-year design to be about 26.7 inches based on our recommended design R-values (section D.1.a.). It appears the pavement rehabilitation will require additional structure (i.e. a bituminous overlay) following SFDR treatment. In order to meet a GE requirement of 26.7 inches for a 2- year design, a 4- inch overlay placed on top of the 7-inch SFDR treatment would be required. We recommend the 4-inch overlay, consist of two lifts of bituminous pavement (2 inches each). C.1.b. Anticipated Grade Changes We understand this project will be able to accommodate the small changes in grade for tie-ins to existing driveways and intersections. The use of SFDR with Engineered Emulsion (EE) provides a bound pavement with up to a 1.8 GE equivalency. A GE equivalency of 1.8 was used in this project. MnDOT s Flexpave program uses a more conservative value of 1. GE equivalency. Stabilizing agents can reduce the changes in grade necessary to construct a structurally sufficient pavement section for SFDR; however we recommend reviewing the anticipated grade change allowances relative to surface elevation changes allowed by MnDOT State Aid. C.1.c. Precautions Regarding Changed Information We have attempted to describe our understanding of the proposed construction to the extent it was reported to us by others. Depending on the extent of available information, assumptions may have been made based on our experience with similar projects. If we have not correctly recorded or interpreted the project details, we should be notified. New or changed information could require additional evaluation, analyses and/or recommendations.

14 Washington County Public Works Revised Project B733. November 4, 2 Page 1 C.2. Design and Construction Considerations C.2.a. Visual Assessment of Pavement Surface Condition A detailed visual assessment of the pavement surface condition was not included in the scope of this evaluation. However, we were able to make general observations of the surface during the GPR operations, where we noted surface conditions that included transverse cracking and patching. The wheel paths were patched throughout the entire segment on both lanes. The pavements appeared to be in poor to fair condition overall. The latest Pavement Quality Index (PQI a composite rating of surface condition and ride quality) is 38 for CSAH according to the County. C.2.b. Pavement Repair We understand that an SFDR followed by an overlay, is being considered for CSAH. Based on boring data and information obtained from the GPR, it appears there is adequate pavement section thickness to allow for the SFDR approach on this segment. For SFDR, the average bituminous thickness of approximately 6 to 6 1/2 inches is enough to allow a reclamation (pulverization) depth of 1 inches. This will result in a blend of approximately 6% asphalt and 3% of the base material. The reclaimed material can either be left in place or windrowed and stockpiled so that grading, excavation work, or stabilization of subgrade soils can proceed. The left-inplace or replaced reclaim is then stabilized to a predetermined depth, compacted and overlaid with bituminous pavement. From a design perspective, it is our opinion that SFDR is a suitable repair alternative; however, we provide the following considerations: Reclamation should not extend into subgrade materials that are unsuitable for base construction, such as silts and clays. Reclamation inherently creates a certain level of fluff. The reclaimed material, being less dense than the original in-place pavement, will result in a higher elevation cross section than the original pavement. Extra care should be taken to compact the reclaimed material to an optimum density. Compaction aid materials can be introduced to facilitate compaction.

15 Washington County Public Works Revised Project B733. November 4, 2 Page 11 A higher pavement elevation will affect ditch slopes and shouldering requirements. The reclaimed material can be spread across shoulder areas to reduce fluff, as well as the amount of shouldering material required. State Aid Design Standards should be reviewed, if applicable, based on surface elevation changes. Depending on grade requirements, premilling could be performed prior to the reclamation. Performing premilling would allow the 1% milled bituminous material to be recycled into the hot mix asphalt (HMA) overlay. Premilling would also minimize the need to remove excess reclaimed material in order to maintain the existing roadway surface elevation upon completion of an overlay. Subgrade corrections will generally not be necessary as part of the SFDR process, though in the case of extreme subgrade issues, additional evaluation and possible supplementary repair may be warranted. We recommend selecting areas showing poor effective GE as supplemental locations for the cores/slabs and base material required to perform the SFDR mix designs. Our complete recommendations are presented below in Sections D. D. Recommendations D.1. Pavements D.1.a. Design R-value As detailed above, we have backcalculated R-value results from FWD testing (section B.), which represent in-situ values and will tend to be conservative relative to laboratory tests on re-molded soils. The th percentile R-value from FWD was With consideration of the sandy soils encountered in several borings, it is our opinion that an R-value of 2 can be used for thickness design purposes.

16 Washington County Public Works Revised Project B733. November 4, 2 Page 12 D.1.b. Materials and Compaction We recommend performing a laboratory SFDR mix design in order to establish stabilizer binder type, moisture and binder contents and maximum density for project materials. This design will require samples of the bituminous materials (via core/slab) as well as the base material. Sampling procedures should be established to provide representative material from the entire roadway. Extensive variation in roadway materials may result in more than one design being required. We recommend compacting the bituminous pavement overlay to at least 92 percent of the maximum theoretical Rice density. D.2. Construction Quality Control D.2.a. Excavation Observations for Subcuts We recommend having a geotechnical engineer observe all excavations related to pavement construction. The purpose of the observations is to evaluate the competence of the geologic materials exposed in the excavations. D.2.b. Materials Testing We recommend dynamic cone penetrometer (DCP) testing on embankment, aggregate base and reclaimed materials where subcuts and corrections are necessary. It is our recommendation that bituminous mixes meet MnDOT designation SPWEA34C and SPNWB33B. The PG8-34 asphalt grade utilized in the wearing course has typically delayed thermal cracking in new construction and overlays over SFDR pavements. The added pavement life provided will normally outweigh the greater initial asphalt cost in a life cycle analysis. All mixes should meet the requirements outlined in MnDOT Specification 236. We recommend the bituminous be placed in two lifts. However, for late season work one lift of 4 inches using SPWEB24C may be utilized to provide more time available for compaction. We recommend tack coat meeting MnDOT Specification 237 be placed between the HMA lifts and along vertical faces where paving will match adjacent pavement. We recommend Gyratory tests on bituminous mixes to evaluate strength and air voids, and density tests to evaluate compaction.

17 Washington County Public Works Revised Project B733. November 4, 2 Page 13 We recommend testing of SFDR placement including gradations and moisture contents of recycled materials, checks for asphalt emulsion content and testing of the stabilized mixture. D.2.c. Cold Weather Precautions SFDR should be performed only when weather conditions are favorable, including temperatures of degrees Fahrenheit and rising with no call for freezing temperatures in the 48-hour forecast. The work should also proceed only under dry conditions. E. Procedures E.1. Penetration Test Borings The penetration test borings were drilled with a truck-mounted core and auger drill equipped with a solid-stem auger. The borings were performed in accordance with ASTM International Standard Test Method D 142. Penetration test samples were taken at 2 1/2 foot intervals to the depth of termination. Actual sample intervals and corresponding depths are shown on the boring logs. E.2. Material Classification and Testing E.2.a. Visual and Manual Classification The geologic materials encountered were visually and manually classified in accordance with ASTM Test Method D A chart explaining the classification system is attached. Samples were sealed in jars or bags and returned to our facility for review and storage. E.2.b. Laboratory Testing The results of the laboratory tests performed on geologic material samples are noted on or follow the appropriate attached exploration logs. The tests were performed in accordance with ASTM or AASHTO procedures.

18 Washington County Public Works Revised Project B733. November 4, 2 Page 14 E.3. Groundwater Measurements The drillers checked for groundwater as the penetration test borings were advanced, and again after auger withdrawal. The boreholes were then backfilled or allowed to remain open for an extended period of observation as noted on the boring logs. E.4. Ground Penetrating Radar E.4.a. Data Collection GPR scans of the pavement were collected according to GSSI, Inc. (manufacturer) SIR-2 processor settings established by MnDOT at an interval of one scan per lineal foot, approximately in the center of each travel lane. A calibration file, required for data post-processing, was collected at the beginning of the testing day. The RoadScan system from GSSI, Inc. allows for real-time monitoring of the GPR scan during testing, as well as for the entry of user marks to note roadway events such as bridges and intersections. This capability was used to mark and tie in the future pavement core/boring locations with GPS coordinates and the GPR scan to the extent possible. GPS data was also collected continuously along each route during the GPR scan. E.4.b. Analysis Pavement layer identification was accomplished using RADAN 7., a software package included with the GSSI, Inc. RoadScan system. The software includes tools to aid in delineating pavement layer transitions and automatically calculates their depths from the pavement surface using the calibration file(s) collected prior to or following testing. The identified layers were compared to the measured thicknesses from borings to validate the accuracy of those calculated by the software.

19 Washington County Public Works Revised Project B733. November 4, 2 Page E.. Falling Weight Deflectometer E..a. Testing A Dynatest TM Model 82E FWD was originally used for deflection testing. Data used for this roadway was collected under the terms of a separate contract with the County. Data collected by the FWD during testing include the deflections, impulse loads, pavement surface temperature, and the ambient air temperature. E..b. Analysis Effective R-value provides a measure of the stiffness of the pavement subgrade soil. R-value calculations are computed using the Hogg Model, which represents the subgrade as a soil mass of finite depth over a stiff layer. Hogg Model resilient modulus values are corrected for seasonal effects and for congruence to backcalculated resilient modulus values, and finally converted to R-value by methods described in MnDOT Investigation 21. Hogg R-values are often conservative in granular soils, such as sands, and will reflect the moisture conditions in fine-grained soils such as clays. Because Hogg Model-calculated R-values are also relatively conservative compared to methods where an infinite half-space is considered, and seasonal adjustments are used, we make no further reduction of our results as they are presented. The effective GE from the FWD data was calculated using a method developed by MnDOT in their Investigation 19 Interim Report. The process uses the seasonally corrected deflection measured at the center of the FWD load and an estimate of the subgrade R-value from the test data. GE, when used for design of new pavement, provides a pavement structure in equivalent inches of MnDOT Class aggregate base.

20 Washington County Public Works Revised Project B733. November 4, 2 Page 16 F. Qualifications F.1. Variations in Subsurface Conditions F.1.a. Material Strata Our evaluation, analyses and recommendations were developed from a limited amount of site and subsurface information. It is not standard engineering practice to retrieve material samples from exploration locations continuously with depth, and therefore strata boundaries and thicknesses must be inferred to some extent. Strata boundaries may also be gradual transitions, and can be expected to vary in depth, elevation and thickness away from the exploration locations. Variations in subsurface conditions present between exploration locations may not be revealed until additional exploration work is completed, or construction commences. If any such variations are revealed, our recommendations should be re-evaluated. Such variations could increase construction costs, and a contingency should be provided to accommodate them. F.1.b. Groundwater Levels Groundwater measurements were made under the conditions reported herein and shown on the exploration logs, and interpreted in the text of this report. It should be noted that the observation period was relatively short, and groundwater can be expected to fluctuate in response to rainfall, flooding, irrigation, seasonal freezing and thawing, surface drainage modifications and other seasonal and annual factors. F.2. Continuity of Professional Responsibility F.2.a. Plan Review This report is based on a limited amount of information, and a number of assumptions were necessary to help us develop our recommendations. It is recommended that our firm review the geotechnical aspects of the designs and specifications, and evaluate whether the design is as expected, if any design changes have affected the validity of our recommendations, and if our recommendations have been correctly interpreted and implemented in the designs and specifications.

21 Washington County Public Works Revised Project B733. November 4, 2 Page 17 F.2.b. Construction Observations and Testing It is recommended that we be retained to perform observations and tests during construction, such as quality assurance during the SFDR process. This will allow correlation of the conditions encountered during construction with those encountered by the borings, GPR and core information, and provide continuity of professional responsibility. F.3. Use of Report This report is for the exclusive use of the parties to which it has been addressed. Without written approval, we assume no responsibility to other parties regarding this report. Our evaluation, analyses and recommendations may not be appropriate for other parties or projects. F.4. Standard of Care In performing its services, Braun Intertec used that degree of care and skill ordinarily exercised under similar circumstances by reputable members of its profession currently practicing in the same locality. No warranty, express or implied, is made.

22 Appendix

23 F:\2\B733-.dwg,Geotech CSAH,1/8/2 9:3:4 AM GEOTECHNICAL EVALUATION CSAH STILLWATER, MINNESOTA SOIL BORING LOCATION SKETCH 111 Hampshire Avenue S Minneapolis, MN 438 PH. (92) 99-2 FAX (92) Project No: B733. Drawing No: B733- Scale: Drawn By: Date Drawn: Checked By: Last Modified: N DENOTES APPROXIMATE LOCATION OF STANDARD PENETRATION TEST BORING 2' SCALE: 1" = ' 1" = ' REJ 9/24/ AG 1/8/ ' Sheet: 3 of Fig: 3

24 L O G O F B O R I N G (See Descriptive Terminology sheet for explanation of abbreviations) Braun Project B733. GEOTECHNICAL EVALUATION Washington County Stillwater, Minnesota DRILLER: Depth feet Symbol PAV FILL J. Chermak (Soil-ASTM D2488 or D2487, Rock-USACE EM ) 4 3/4 inches of bituminous over 6 inches of aggregate base. FILL: Silty Clayey Sand, fine- to coarse-grained, with Gravel, brown to dark brown, moist. END OF BORING. METHOD: Water not observed to cave-in depth of 4 feet immediately after withdrawal of auger. Boring then backfilled. 3 1/4" HSA, Autohammer Description of Materials BORING: LOCATION: CSAH ; See attached sketch. DATE: 1/1/ SCALE: 1" = 4' BPF 29 WL ST-13 MC % P2 % Tests or Notes LOG OF BORING N:\GINT\PROJECTS\AX PROJECTS\2\733..GPJ BRAUN_V8_CURRENT.GDT 11/4/ 13:8 B733. Braun Intertec Corporation ST-13 page 1 of 1

25 L O G O F B O R I N G (See Descriptive Terminology sheet for explanation of abbreviations) Braun Project B733. GEOTECHNICAL EVALUATION Washington County Stillwater, Minnesota DRILLER: Depth feet Symbol PAV FILL SP J. Chermak (Soil-ASTM D2488 or D2487, Rock-USACE EM ) 4 1/2 inches of bituminous over 8 inches of aggregate base. FILL: Silty Sand, fine- to coarse-grained, with Gravel, brown, moist. POORLY GRADED SAND, fine- to medium-grained, brown, moist. END OF BORING. METHOD: Water not observed to cave-in depth of 3 1/2 feet immediately after withdrawal of auger. Boring then backfilled. 3 1/4" HSA, Autohammer Description of Materials BORING: LOCATION: CSAH ; See attached sketch. DATE: 1/1/ SCALE: 1" = 4' BPF 13 WL 8 4 ST-14 MC % Tests or Notes LOG OF BORING N:\GINT\PROJECTS\AX PROJECTS\2\733..GPJ BRAUN_V8_CURRENT.GDT 11/4/ 13:8 B733. Braun Intertec Corporation ST-14 page 1 of 1

26 L O G O F B O R I N G (See Descriptive Terminology sheet for explanation of abbreviations) Braun Project B733. GEOTECHNICAL EVALUATION Washington County Stillwater, Minnesota DRILLER: Depth feet Symbol PAV FILL FILL FILL J. Chermak (Soil-ASTM D2488 or D2487, Rock-USACE EM ) 8 1/2 inches of bituminous over 6 1/2 inches of aggregate base. FILL: Clayey Sand, dark brown, moist. FILL: Poorly Graded Sand, fine- to coarse-grained, brown, moist. FILL: Silty Sand, fine- to coarse-grained, with Gravel, dark brown, wet. END OF BORING. METHOD: Water not observed to cave-in depth of 4 feet immediately after withdrawal of auger. Boring then backfilled. 3 1/4" HSA, Autohammer Description of Materials BORING: LOCATION: CSAH ; See attached sketch. DATE: 1/1/ SCALE: 1" = 4' BPF 21 WL 7 11 ST- MC % Tests or Notes LOG OF BORING N:\GINT\PROJECTS\AX PROJECTS\2\733..GPJ BRAUN_V8_CURRENT.GDT 11/4/ 13:8 B733. Braun Intertec Corporation ST- page 1 of 1

27 L O G O F B O R I N G (See Descriptive Terminology sheet for explanation of abbreviations) Braun Project B733. GEOTECHNICAL EVALUATION Washington County Stillwater, Minnesota DRILLER: Depth feet Symbol PAV SP J. Chermak (Soil-ASTM D2488 or D2487, Rock-USACE EM ) 9 1/2 inches of bituminous over 6 inches of aggregate base. POORLY GRADED SAND, fine-grained, brown, moist. (Glacial Outwash) END OF BORING. METHOD: Water not observed to cave-in depth of 3 feet immediately after withdrawal of auger. Boring then backfilled. 3 1/4" HSA, Autohammer Description of Materials BORING: LOCATION: CSAH ; See attached sketch. DATE: 1/1/ SCALE: 1" = 4' BPF WL ST-16 MC % 1 Tests or Notes LOG OF BORING N:\GINT\PROJECTS\AX PROJECTS\2\733..GPJ BRAUN_V8_CURRENT.GDT 11/4/ 13:8 B733. Braun Intertec Corporation ST-16 page 1 of 1

28 L O G O F B O R I N G (See Descriptive Terminology sheet for explanation of abbreviations) Braun Project B733. GEOTECHNICAL EVALUATION Washington County Stillwater, Minnesota DRILLER: Depth feet Symbol PAV FILL FILL J. Chermak (Soil-ASTM D2488 or D2487, Rock-USACE EM ) 6 inches of bituminous over 6 inches of aggregate base. FILL: Clayey Sand, brown, moist. FILL: Poorly Graded Sand, fine-grained, dark brown, moist. END OF BORING. METHOD: Water not observed to cave-in depth of 4 feet immediately after withdrawal of auger. Boring then backfilled. 3 1/4" HSA, Autohammer Description of Materials BORING: LOCATION: CSAH ; See attached sketch. DATE: 1/1/ SCALE: 1" = 4' BPF WL ST-17 MC % 12 P2 % 49 Tests or Notes LOG OF BORING N:\GINT\PROJECTS\AX PROJECTS\2\733..GPJ BRAUN_V8_CURRENT.GDT 11/4/ 13:8 B733. Braun Intertec Corporation ST-17 page 1 of 1

29 L O G O F B O R I N G (See Descriptive Terminology sheet for explanation of abbreviations) Braun Project B733. GEOTECHNICAL EVALUATION Washington County Stillwater, Minnesota DRILLER: Depth feet Symbol PAV FILL SP J. Chermak (Soil-ASTM D2488 or D2487, Rock-USACE EM ) 1 inches of bituminous over 7 inches of aggregate base. FILL: Clayey Sand, dark brown, moist. POORLY GRADED SAND, fine-grained, brown, moist. (Glacial Outwash) END OF BORING. METHOD: Water not observed to cave-in depth of 4 feet immediately after withdrawal of auger. Boring then backfilled. 3 1/4" HSA, Autohammer Description of Materials BORING: LOCATION: CSAH ; See attached sketch. DATE: 1/1/ SCALE: 1" = 4' BPF 6 9 WL ST-18 MC % 21 3 Tests or Notes LOG OF BORING N:\GINT\PROJECTS\AX PROJECTS\2\733..GPJ BRAUN_V8_CURRENT.GDT 11/4/ 13:9 B733. Braun Intertec Corporation ST-18 page 1 of 1

30 Descriptive Terminology of Soil Standard D 2487 Classification of Soils for Engineering Purposes (Unified Soil Classification System) 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. 1 Medium... No. 1 to No. 4 Fine... No. 4 to No. 2 Silt... <No. 2, PI< 4 or below A line Clay... <No. 2, PI > 4 and on or about A line Relative Density of Cohesionless Soils Very Loose... to 4 BPF Loose... to 1 BPF Medium dense to 3 PPF Dense to BPF Very dense... over BPF a. Based on the material passing the 3-inch (7mm) sieve. b. If field sample contained cobbles or boulders, or both, add with cobbles or boulders or both to group name. c. Cu = D6/D1 C c = (D3) 2 D1 x D6 d. If soil contains % sand, add with sand to group name. e. Gravels with 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 clay f. If fines classify as CL-ML, use dual symbol GC-GM or SC-SM. g. If fines are organic, add with organic fines: to group name. h. If soil contains % gravel, add with gravel to group name. i. Sand with 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 with silt SP-SC poorly graded sand with clay j. If Atterberg limits plot in hatched area, soil is a CL-ML, silty clay. k. If soil contains 1 to 29% plus No. 2, add with sand or with gravel whichever is predominant. l. If soil contains 3% plus No. 2, predominantly sand, add sandy to group name. m. If soil contains 3% plus No. 2, predominantly gravel, add gravelly to group name. n. PI 4 and plots on or above A line. o. PI < 4 or plots below A line. p. PI plots on or above A lines. q. PI plots below A line. Consistency of Cohesive Soils Very soft... to 1 BPF Soft... 2 to 3 BPF Rather soft... 4 to BPF Medium... 6 to 8 BPF Rather stiff... 9 to 12 BPF Stiff to 16 BPF Very stiff to 3 BPF Hard... over 3 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. All samples were taken with the standard 2 OD split-tube samples, except where noted. Power auger borings were advanced by 4 or 6 diameter continuous flight, solid-stern augers. Soil classifications and strata depths were inferred from disturbed samples augered to the surface, and are therefore, somewhat approximate. 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. 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. Laboratory Tests DD Dry density, pcf OC Organic content, % WD Wet density, pcg S Percent of saturation, % MC Natural moisture content, % SG Specific gravity LL Liquid limit, % C Cohesion, psf PL Plastic limits, % Ø Angle of internal friction PI Plasticity index, % qu Unconfined compressive strength, psf P2 % passing 2 sieve qp Pocket penetrometer strength, tsf TW: TW indicates thin-walled (undisturbed) tube sample. Note: All tests were run in general accordance with applicable ASTM standards. Rev. 9/

31 Project name Project No. Roadway From To Length (mile) Washington County 2 B733 CSAH - North Bound TH 96 CSAH CSAH - North Bound : TH 96 to CSAH , Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft) 1, 1,1 1,2 1,3 1,4 1, 1,6 1,7 1,8 1,9 2, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft) 2, 2,1 2,2 2,3 2,4 2, 2,6 2,7 2,8 2,9 3, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft)

32 Project name Project No. Roadway From To Length (mile) Washington County 2 B733 CSAH - North Bound TH 96 CSAH CSAH - North Bound : TH 96 to CSAH 11 3, 3,1 3,2 3,3 3,4 3, 3,6 3,7 3,8 3,9 4, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft) 4, 4,1 4,2 4,3 4,4 4, 4,6 4,7 4,8 4,9, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft),,1,2,3,4,,6,7,8,9 6, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft)

33 Project name Project No. Roadway From To Length (mile) Washington County 2 B733 CSAH - North Bound TH 96 CSAH CSAH - North Bound : TH 96 to CSAH 11 6, 6,1 6,2 6,3 6,4 6, 6,6 6,7 6,8 6,9 7, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft) 7, 7,1 7,2 7,3 7,4 7, 7,6 7,7 7,8 7,9 8, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft) 8, 8,1 8,2 8,3 8,4 8, 8,6 8,7 8,8 8,9 9, Depth (in.) Station (ft) Bit Depth (in.) Agg Depth (in.)

34 Project name Project No. Roadway From To Length (mile) Washington County 2 B733 CSAH - North Bound TH 96 CSAH CSAH - North Bound : TH 96 to CSAH 11 9, 9,1 9,2 9,3 9,4 9, 9,6 9,7 9,8 9,9 1, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft)

35 Project name Project No. Roadway From To Length (mile) Washington County 2 B733 CSAH - South Bound CSAH 11 TH CSAH - South Bound : CSAH 11 to TH , Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft) 1, 1,1 1,2 1,3 1,4 1, 1,6 1,7 1,8 1,9 2, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft) 2, 2,1 2,2 2,3 2,4 2, 2,6 2,7 2,8 2,9 3, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft)

36 Project name Project No. Roadway From To Length (mile) Washington County 2 B733 CSAH - South Bound CSAH 11 TH CSAH - South Bound : CSAH 11 to TH 96 3, 3,1 3,2 3,3 3,4 3, 3,6 3,7 3,8 3,9 4, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft) 4, 4,1 4,2 4,3 4,4 4, 4,6 4,7 4,8 4,9, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft),,1,2,3,4,,6,7,8,9 6, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft)

37 Project name Project No. Roadway From To Length (mile) Washington County 2 B733 CSAH - South Bound CSAH 11 TH CSAH - South Bound : CSAH 11 to TH 96 6, 6,1 6,2 6,3 6,4 6, 6,6 6,7 6,8 6,9 7, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft) 7, 7,1 7,2 7,3 7,4 7, 7,6 7,7 7,8 7,9 8, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft) 8, 8,1 8,2 8,3 8,4 8, 8,6 8,7 8,8 8,9 9, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft)

38 Project name Project No. Roadway From To Length (mile) Washington County 2 B733 CSAH - South Bound CSAH 11 TH CSAH - South Bound : CSAH 11 to TH 96 9, 9,1 9,2 9,3 9,4 9, 9,6 9,7 9,8 9,9 1, Depth (in.) 1 2 Bit Depth (in.) Agg Depth (in.) 2 Station (ft)

39 Braun Intertec Corporation - Project No. BL Test Date: Jul 29, 21 Average Client: Washington County Public Works Daily ESALs: varies th/8th Percentile Roadway: CSAH Total AC: varies Seasonal Correction Factor: 1. From: TH-36 X-ING Prev. Day's Avg. Air Temp.: 71 F To: MNTH-9 ST CROIX TR N X-ING TONN Pvm't. Effective Maximum Location Surf. Test Effective Granular Overlay Axle Load (miles) Temp. Load Sensor Readings (mils) Subgrade Equiv. Thickness Capacity Left Right Lane Time ( F) (lbf) d(1) d(2) d(3) d(4) d() d(6) d(7) R-value (in.) (in.) (Tons) Comments. CL - TH 36 X-ING - START NEW SECTION".1 CL - MNTH 36 X-ING - END SECTION".84 Right-1 11: L TRANS./LONGIT..84 Right-1 11: L TRANS./LONGIT..84 Right-1 11: L TRANS./LONGIT..84 Right-1 11: L TRANS./LONGIT..1 Right-1 11: L TRANS./LONGIT..1 Right-1 11: L TRANS./LONGIT..1 Right-1 11: L TRANS./LONGIT..1 Right-1 11: L TRANS./LONGIT..1 Right-1 13: L TRANS./LONGIT..1 Right-1 13: L TRANS./LONGIT..1 Right-1 13: L TRANS./LONGIT..1 Right-1 13: L TRANS./LONGIT..2 Right-1 11: L TRANS./LONGIT..2 Right-1 11: L TRANS./LONGIT..2 Right-1 11: L TRANS./LONGIT..2 Right-1 11: L TRANS./LONGIT..2 Right-1 12: L TRANS./LONGIT..2 Right-1 12: L TRANS./LONGIT..2 Right-1 12: L TRANS./LONGIT..2 Right-1 12: L TRANS./LONGIT..267 CL - CURVE CREST BLVD".29 Right-1 11: L TRANS./LONGIT..29 Right-1 11: L TRANS./LONGIT..29 Right-1 11: L TRANS./LONGIT..29 Right-1 11: L TRANS./LONGIT..3 Right-1 12: L TRANS./LONGIT..3 Right-1 12: L TRANS./LONGIT..3 Right-1 12: L TRANS./LONGIT..3 Right-1 12: L TRANS./LONGIT..36 CL - CURVE CREST BLVD".4 Right-1 11: L TRANS./LONGIT..4 Right-1 11: L TRANS./LONGIT..4 Right-1 11: L TRANS./LONGIT..4 Right-1 11: L TRANS./LONGIT..4 Right-1 12: L TRANS./LONGIT..4 Right-1 12: L TRANS./LONGIT..4 Right-1 12: L TRANS./LONGIT..4 Right-1 12: L TRANS./LONGIT.. Right-1 11: L TRANS./LONGIT.. Right-1 11: L TRANS./LONGIT.. Right-1 11: L TRANS./LONGIT.. Right-1 11: L TRANS./LONGIT.. Right-1 12: L TRANS./LONGIT.. Right-1 12: L TRANS./LONGIT.. Right-1 12: L TRANS./LONGIT.. Right-1 12: L TRANS./LONGIT..2 CL - WILD PINES LN RH".91 CL - ORLEANS ST RT".6 Right-1 12: L TRANS./LONGIT..6 Right-1 12: L TRANS./LONGIT..6 Right-1 12: L TRANS./LONGIT..6 Right-1 12: L TRANS./LONGIT..6 Right-1 11: L TRANS./LONGIT..6 Right-1 11: L TRANS./LONGIT..6 Right-1 11: L TRANS./LONGIT..6 Right-1 11: L TRANS./LONGIT..7 Right-1 11: L TRANS./LONGIT..7 Right-1 11: L TRANS./LONGIT..7 Right-1 11: L TRANS./LONGIT..7 Right-1 11: L TRANS./LONGIT..7 Right-1 12: L TRANS./LONGIT..7 Right-1 12: L TRANS./LONGIT..7 Right-1 12: L TRANS./LONGIT..7 Right-1 12: L TRANS./LONGIT..786 CL - COTTAGE DR LH".8 Right-1 11: L TRANS./LONGIT..8 Right-1 11: L TRANS./LONGIT..8 Right-1 11: L TRANS./LONGIT..8 Right-1 11: L TRANS./LONGIT..8 Right-1 12: L TRANS..8 Right-1 12: L TRANS..8 Right-1 12: L TRANS..8 Right-1 12: L TRANS..9 Right-1 11: L TRANS./LONGIT..9 Right-1 11: L TRANS./LONGIT..9 Right-1 11: L TRANS./LONGIT.

40 Braun Intertec Corporation - Project No. BL Test Date: Jul 29, 21 Average Client: Washington County Public Works Daily ESALs: varies th/8th Percentile Roadway: CSAH Total AC: varies Seasonal Correction Factor: 1. From: TH-36 X-ING Prev. Day's Avg. Air Temp.: 71 F To: MNTH-9 ST CROIX TR N X-ING TONN Pvm't. Effective Maximum Location Surf. Test Effective Granular Overlay Axle Load (miles) Temp. Load Sensor Readings (mils) Subgrade Equiv. Thickness Capacity Left Right Lane Time ( F) (lbf) d(1) d(2) d(3) d(4) d() d(6) d(7) R-value (in.) (in.) (Tons) Comments.9 Right-1 11: L TRANS./LONGIT..9 Right-1 12: H TRANS..9 Right-1 12: H TRANS..9 Right-1 12: H TRANS..9 Right-1 12: H TRANS..924 Right-1 12: M TRANS..924 Right-1 12: M TRANS..924 Right-1 12: M TRANS..924 Right-1 12: M TRANS..936 CL - CROIXWOOD BLVD - START NEW SECTION".9 Right-1 11: L TRANS./LONGIT..9 Right-1 11: L TRANS./LONGIT..9 Right-1 11: L TRANS./LONGIT..9 Right-1 11: L TRANS./LONGIT..97 CL - CROIXWOOD BLVD - END SECTION".97 CL - CROIXWOOD BLVD - BEGIN SECTION" 1.6 Right-1 11: L TRANS./LONGIT. 1.6 Right-1 11: L TRANS./LONGIT. 1.6 Right-1 11: L TRANS./LONGIT. 1.6 Right-1 11: L TRANS./LONGIT. 1.2 CL - AUTUMN WAY" 1.1 Right-1 11: L TRANS./LONGIT. 1.1 Right-1 11: L TRANS./LONGIT. 1.1 Right-1 11: L TRANS./LONGIT. 1.1 Right-1 11: L TRANS./LONGIT CL - WILLARD ST W RH" 1.2 Right-1 11: L TRANS./LONGIT. 1.2 Right-1 11: L TRANS./LONGIT. 1.2 Right-1 11: L TRANS./LONGIT. 1.2 Right-1 11: L TRANS./LONGIT. 1.2 CL - OAKRIDGE RD LH" 1.23 CL - PINE ST RH" CL - DUNDEE PL LH" 1.3 Right-1 11: L TRANS./LONGIT. 1.3 Right-1 11: L TRANS./LONGIT. 1.3 Right-1 11: L TRANS./LONGIT. 1.3 Right-1 11: L TRANS./LONGIT. 1.3 CL - OAK ST RH " CL - FAIRMEADOWS RD LH" 1.4 Right-1 11: M TRANS./LONGIT. 1.4 Right-1 11: M TRANS./LONGIT. 1.4 Right-1 11: M TRANS./LONGIT. 1.4 Right-1 11: M TRANS./LONGIT CL - DEER PATH LH" CL - PINE TREE TRAIL RH" 1. Right-1 11: M TRANS./LONGIT. 1. Right-1 11: M TRANS./LONGIT. 1. Right-1 11: M TRANS./LONGIT. 1. Right-1 11: M TRANS./LONGIT CL - SEELEY ST RH" 1.6 Right-1 11: M TRANS./LONGIT. 1.6 Right-1 11: M TRANS./LONGIT. 1.6 Right-1 11: M TRANS./LONGIT. 1.6 Right-1 11: M TRANS./LONGIT CL - BRICK ST" 1.67 CL - HEMLOCK ST RH" 1.7 Right-1 12: M TRANS./LONGIT. 1.7 Right-1 12: M TRANS./LONGIT. 1.7 Right-1 12: M TRANS./LONGIT. 1.7 Right-1 12: M TRANS./LONGIT CL - GROVE ST " 1.8 Right-1 12: M TRANS./LONGIT. 1.8 Right-1 12: M TRANS./LONGIT. 1.8 Right-1 12: M TRANS./LONGIT. 1.8 Right-1 12: M TRANS./LONGIT CL - CENTER ST RH" 1.88 CL - SHERBURNE ST " 1.9 Right-1 12: M TRANS./LONGIT. 1.9 Right-1 12: M TRANS./LONGIT. 1.9 Right-1 12: M TRANS./LONGIT. 1.9 Right-1 12: M TRANS./LONGIT RIGHT TURN TO CSAH NORTH" 1.99 CL - RAMSEY ST" 2. Right-1 12: M TRANS./LONGIT. 2. Right-1 12: M TRANS./LONGIT. 2. Right-1 12: M TRANS./LONGIT. 2. Right-1 12: M TRANS./LONGIT CL MYRTLE ST"