Geotechnical Engineering Report Oertli Multifamily East Parmer Lane, Northwest of Dessau Road Austin, Texas November 21, 2014 Terracon Project No. 96145207

Prepared for: CIP Construction Greensboro, North Carolina

Prepared by: Terracon Consultants, Inc. Austin, Texas

Responsive ■ Resourceful ■ Reliable November 21, 2014

CIP Construction 201 North Elm Street Greensboro, North Carolina 27401

Attention Mr. Phillip Arrington P: (336) 275-6198 x 309 E: [email protected]

Regarding: Geotechnical Engineering Report Oertli Multifamily East Parmer Lane, Northwest of Dessau Road Austin, Texas Terracon Project No. 96145207

Dear Mr. Arrington:

Terracon Consultants, Inc. (Terracon) is pleased to submit our Geotechnical Engineering Report for the Oertli Multifamily project to be located on East Parmer Lane, Northwest of Dessau Road, in Austin, Texas. We trust that this report is responsive to your project needs. Please contact us if you have any questions or if we can be of further assistance.

We appreciate the opportunity to work with you on this project and look forward to providing additional Geotechnical Engineering and Construction Materials Testing services in the future.

Terracon Consultants, Inc. 5307 Industrial Oaks Boulevard, Suite 160 Austin, Texas 78735 Registration No. F-3272 P [512] 442 1122 F [512] 442 1181 terracon.com TABLE OF CONTENTS

Page EXECUTIVE SUMMARY ...... i 1.0 INTRODUCTION ...... 1 2.0 PROJECT INFORMATION ...... 1 2.1 Site Location and Description...... 1 2.2 Project Description ...... 2 3.0 SUBSURFACE CONDITIONS ...... 2 3.1 Geology ...... 2 3.2 Typical Profile ...... 2 3.3 Swell Test Results ...... 4 3.4 Groundwater ...... 5 4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION ...... 5 4.1 Geotechnical Considerations ...... 5 4.2 Earthwork...... 6 4.2.1 Compaction Requirements ...... 7 4.2.2 Grading and Drainage ...... 8 4.2.3 Utility Trench Plugs ...... 9 4.3 Floor Slab Subgrade Preparation ...... 9 4.4 Foundation System ...... 11 4.4.1 Design Recommendations – Monolithic Slab-On-Grade ...... 12 4.4.2 Foundation Construction Considerations ...... 14 Slab-on-Grade ...... 14 Foundation Construction Monitoring ...... 15 4.5 Seismic Design Information ...... 15 4.6 Lateral Earth Pressures ...... 15 4.7 Pavements ...... 17 5.0 GENERAL COMMENTS ...... 20

APPENDIX A – FIELD EXPLORATION Exhibit A-1 Site Location Map Exhibit A-2 Boring Location Plan Exhibit A-3 Boring Location Aerial Exhibit A-4 Field Exploration Description Exhibits A-5 through A-17 Boring Logs

APPENDIX B – LABORATORY TESTING Exhibit B-1 Laboratory Testing Exhibit B-2 ASTM D422 – Grain Size Distribution

APPENDIX C – SUPPORTING DOCUMENTS Exhibit C-1 General Notes Exhibit C-2 Unified Soil Classifications Exhibit C-3 City of Austin MSWL Certification of Compliance

Responsive ■ Resourceful ■ Reliable Geotechnical Engineering Report Oertli Multifamily ■ Austin, Texas November 21, 2014 ■ Terracon Project No. 96145207

EXECUTIVE SUMMARY

A geotechnical investigation has been performed for the Oertli Multifamily project to be located on East Parmer Lane, Northwest of Dessau Road, in Austin, Texas. Subsurface conditions were evaluated using 13 borings drilled at the site.

Based on the information obtained from our subsurface exploration, the site can be developed for the proposed project. The following geotechnical considerations were identified: n Stripping should include surface vegetation, trees, loose topsoil, or other unsuitable materials such as organic matter, as well as the over-excavation required in the building areas. Proofrolling should be performed to detect weak areas. Weak areas such as subgrades exhibiting rutting and/or deflection should be removed and replaced with select fill or soils exhibiting similar characteristics as the adjacent in-situ soils. n Highly expansive clay soils (Stratum I) were encountered in the borings. Structures supported over these soils can experience higher than normal/tolerable shrink/swell movements. Subgrade preparation for grade-supported floor slab design is presented in Section 4.3 and is also discussed in Section 4.1. n The proposed apartment buildings can be supported on monolithic slab-on-grade foundation systems provided proper subgrade preparation is implemented. The slab and beam foundations should be sized for a total load allowable bearing pressure of 2,500 psf or a net dead load allowable bearing pressure of 1,700 psf, if bearing in properly compacted select fill soils. n Pavements in parking areas should be designed with at least 2 inches of asphalt over 9 inches of base material over moisture conditioned subgrade. As an alternative, 5 inches of reinforced concrete over moisture conditioned subgrade may be used. n Pavements in light to medium duty traffic areas should be designed with at least 2.5 inches of asphalt over 10 inches of base material over moisture conditioned subgrade. As an alternative, 6 inches of reinforced concrete over moisture conditioned subgrade may be used. n Close monitoring of the construction operations discussed herein will be critical in achieving the design subgrade support. We therefore recommend that the Terracon be retained to monitor this portion of the work.

This summary should be used in conjunction with the entire report for design purposes. It should be recognized that details were not included or fully developed in this section, and the report must be read in its entirety for a comprehensive understanding of the items contained herein. Section 5.0 – GENERAL COMMENTS should be read for an understanding of the report limitations.

Responsive ■ Resourceful ■ Reliable GEOTECHNICAL ENGINEERING REPORT OERTLI MULTIFAMILY EAST PARMER LANE, NORTHWEST OF DESSAU ROAD AUSTIN, TEXAS Terracon Project No. 96145207 November 21, 2014

1.0 INTRODUCTION

Terracon is pleased to submit our Geotechnical Engineering Report for the Oertli Multifamily project to be located on East Parmer Lane, Northwest of Dessau Road, in Austin, Texas. This project was authorized by Mr. Dennis Burton with CIP Construction through signature of our “Supplement to Agreement for Services” on October 10, 2014. The project scope was performed in general accordance with Terracon Proposal No. P96141028 dated August 15, 2014.

The purpose of this report is to describe the subsurface conditions observed at the borings drilled for this project, analyze and evaluate the test data, and provide recommendations with respect to:

■ Foundation design and construction recommendations; ■ Site, subgrade, and fill preparation; ■ Lateral earth pressure and drainage for site retaining walls; ■ Pavement design and construction; and ■ Seismic site classification according to IBC 2012.

2.0 PROJECT INFORMATION

2.1 Site Location and Description

Item Description The project site is an approximately 14.88-acre tract of land located on Location the southeast corner of the intersection of East Parmer Lane and Pearl Retreat Lane, in Austin, Texas. Based on information presented in Terracon Phase I ESA report No. Existing Improvements / 96147611 dated November 7, 2014, the site has been Historical Use undeveloped/agricultural land since at least 1885 through the present day. No structures are currently located on the site. The site is generally covered with grass and bushes, with the exception Existing Ground Cover of the south point of the site, which is densely wooded.

Responsive ■ Resourceful ■ Reliable Geotechnical Engineering Report Oertli Multifamily ■ Austin, Texas November 21, 2014 ■ Terracon Project No. 96145207

Item Description Unknown, but the site appears to be relatively flat based on visual Existing Topography observation.

2.2 Project Description

Item Description Site layout See Exhibit A-2, Boring Location Plan, in Appendix A. The project will include the construction of 12 two to three-story apartment Proposed Improvements buildings, along with a clubhouse, a pool, and surface pavement areas. Building Construction Anticipated to be wood-frame construction. Finished Floor Elevation Unknown; assumed to be within one to two feet of existing ground surface. Maximum Column Loads Unknown; typical light-frame loading anticipated. Grading Assumed minimal cuts and fills. Cut and Fill Slopes Not anticipated. Free-standing Retaining Not anticipated. Walls Below-Grade Areas Not anticipated.

3.0 SUBSURFACE CONDITIONS

3.1 Geology

Based on our review of available geologic information1 and the samples obtained from the test borings, the study area appears to lie within an area characterized by the Austin Group of Upper Cretaceous Age. The Austin Group is generally comprised of tan to gray chalky limestone and marls, and is commonly overlain by a variably thick layer of moderate to high plasticity clayey soils.

3.2 Typical Profile

Based on the results of the borings, subsurface conditions on the project can be generalized as below.

1 Garner, L.E. and Young, K.P., “Environmental Geology of the Austin Area: An Aid to Urban Planning”, Bureau of Economic Geology, The University of Texas at Austin, 1976.

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Approximate Soil Depth Range Description Material Encountered Consistency / of Stratum, Soil Density feet Stratum I 0 to 6 Fat Clay (CH) Stiff to Hard Stratum II 2 to >15 Fat Clay (CH) to Lean Clay (CL) Very Stiff to Hard

The Stratum I dark brown to grayish-brown soils encountered in the borings generally exhibited a very high shrink/swell potential as indicated by the following measured liquid limits, plastic limits, and fines contents (percent passing the No. 200 sieve):

Sample Liquid Limit Plastic Limit Plasticity Index Fines Depth (feet) Location (%) (%) (%) (%) Boring B-2 2 – 4 70 21 49 - Boring B-5 2 – 4 51 20 31 - Boring B-7 2 – 4 75 24 51 - Boring B-11 2 – 4 71 22 49 94 Boring B-12 4 – 6 69 20 49 90 Boring B-13 4 – 6 68 22 46 93 Average - 67 22 46 92

The in-situ moisture content of the Stratum I soils ranged from 4 percent dry of, to 12 percent wet of corresponding plastic limits. The measured values of unconfined compressive strength of the Stratum I fat clay soils were found to vary from approximately 1.2 to 9.9 tons per square foot (tsf) (average ~3.8 tsf). Hand penetrometer (HP) readings on the Stratum I soils were found to vary from 1.0 to 4.5 tsf. Generally, the Stratum I soils was visually observed to be significantly darker in color than the Stratum II soils.

The Stratum II pale brown to light gray to light brownish-gray to yellow to grayish-brown soils encountered in the borings generally exhibited a moderate to high shrink/swell potential as indicated by the following measured liquid limits, plastic limits, and fines contents:

Sample Liquid Limit Plastic Limit Plasticity Index Fines Depth (feet) Location (%) (%) (%) (%) Boring B-1 4 – 6 38 16 12 - Boring B-2 6 – 8 50 21 29 - Boring B-3 4 – 6 31 18 13 87 Boring B-4 6 – 7½ 38 18 20 - Boring B-5 6 – 8 37 20 17 73

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Sample Liquid Limit Plastic Limit Plasticity Index Fines Depth (feet) Location (%) (%) (%) (%) Boring B-6 4 – 6 35 17 18 - Boring B-7 8 – 10 31 19 12 - Boring B-8 4 – 6 34 20 14 - Boring B-9 8 – 10 38 18 20 - Boring B-10 6 – 8 38 18 20 - Boring B-11 6½ – 8 34 17 17 - Boring B-12 8 – 10 33 17 16 - Average - 36 18 17 -

The in-situ moisture content of the Stratum II soils ranged from 5 percent dry of, to 2 percent wet of corresponding plastic limits. The measured values of unconfined compressive strength of the Stratum II soils were found to vary from approximately 3.2 to 3.9 tsf. Hand penetrometer readings on the Stratum II soils were found to vary from 2.5 to 4.5 tsf. Standard penetration test (SPT) blow counts (N-values) for the Stratum II soils were found to vary from 30 to 79 blows per foot of penetration.

Conditions encountered at the boring locations are indicated on each individual boring log. Stratification boundaries on the boring logs represent the approximate location of changes in subsurface material types; in-situ, the transition between materials may be gradual. Details for the borings can be found on the boring logs on Exhibits A-5 through A-17 of Appendix A.

3.3 Swell Test Results

Three free swell tests were performed on soil samples and the results are presented in the following table. After surcharge pressures were applied that represent the approximate in-situ overburden pressure, the sample was inundated with water for about 72 hours while measurements of vertical displacement were taken. The magnitude of swell is recorded as a function of the change in thickness during the test in relation to the thickness of the sample loaded to its overburden pressure.

Approx. Confining Boring Initial Final Sample Pressure Stratum Free Swell, % No. Moisture, % Moisture, % Depth, ft. (psf) B-1 4 – 6 600 II 12 15 0.6 B-8 8 – 10 1,080 II 14 16 0.4 B-12 6 – 8 840 II 14 16 0.0

Based on our laboratory results, the samples tested generally exhibit a low swell potential.

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3.4 Groundwater

The borings were dry augered to depths of about 15 feet below existing grade. Groundwater was not observed during dry augering.

Although not observed, groundwater at the site should be anticipated in more pervious seams/fissures of the subgrade soils and/or in “perched” areas immediately above less permeable seams/layers of the subsurface soils. During periods of wet weather, zones of seepage may appear and isolated zones of “perched water” may become trapped (or confined) by zones possessing a low permeability. Please note that it often takes several hours/days for water to accumulate in a borehole, and geotechnical borings are relatively fast, short-term boreholes that are backfilled the same day. Long-term groundwater readings can more accurately be achieved using monitoring wells. Please contact us if this is desired. Groundwater conditions should be evaluated just prior to construction.

4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION

The following recommendations are based upon the data obtained in our field and laboratory programs, project information provided to us, and on our experience with similar subsurface and site conditions.

4.1 Geotechnical Considerations

Based on our test borings, expansive soils (Stratum I) that exhibit a very high potential for volumetric change during moisture variations are present at the site. The soils exhibit a Potential Vertical Rise (PVR) of up to about 3½ inches as estimated by the Texas Department of Transportation (TxDOT) Method TEX-124-E, if present in a dry condition.

This report provides recommendations to help mitigate the effects of soil shrinkage and expansion. However, even if these procedures are followed, some movement and cracking in the structures should be anticipated. The severity of cracking and other damage such as uneven floor slabs will probably increase if any modification of the site results in excessive wetting or drying of the expansive soils. Eliminating the risk of movement and distress may not be feasible, but it may be possible to further reduce the risk of movement if significantly more expensive measures are used during construction.

Based on the subsurface conditions observed at the site, it is our opinion that monolithic slab-on- grade foundation systems would be appropriate to support the proposed multi-family apartment buildings and clubhouse provided the subgrade for the buildings are prepared to reduce the shrink/swell potential of the subgrade to more tolerable levels. Recommendations for this type of

Responsive ■ Resourceful ■ Reliable 5 Geotechnical Engineering Report Oertli Multifamily ■ Austin, Texas November 21, 2014 ■ Terracon Project No. 96145207 foundation system are presented in the following subsections along with other geotechnical engineering considerations for this project.

4.2 Earthwork

Construction areas should be stripped of vegetation, topsoil, and other unsuitable materials. Roots of trees to be removed within construction areas should be grubbed to full depths, including the dry soil around the roots.

Once final subgrade elevations have been achieved (including the over-excavation required for building pads), the exposed subgrade, should be carefully and thoroughly proofrolled with a 20- ton pneumatic roller or a fully-loaded dump truck to detect weak zones in the subgrade. Weak areas detected during proofrolling, as well as zones containing debris or organics, and voids resulting from removal of tree roots, etc., should be removed and replaced with soils exhibiting similar classification, moisture content, and density as the adjacent in-situ soils. Proper site drainage should be maintained during construction so that ponding of surface runoff does not occur and causes construction delays and/or inhibit site access.

Subsequent to proofrolling, and just prior to placement of fill, the exposed subgrade within the construction areas should be evaluated for moisture and density. If the moisture and/or density requirements do not meet the criteria described in the table below, the subgrade should be scarified to a minimum depth of 6 inches, moisture adjusted and compacted to at least 95 percent of the Standard Proctor (ASTM D 698) maximum dry density.

Select fill and on-site soils should meet the following criteria.

Fill Type 1 USCS Classification Acceptable Location For Placement Imported CL, SC, and/or GC Select fill material should be used for all grade Select Fill 2,3 (7≤PI≤20) adjustments within the building limits. General fill is for use within other non-structural areas General Fill 4 CL, CH, GC of the site. If imported, paving fill should have a PI≤46. 1. Prior to any filling operations, samples of proposed borrow and/or on-site materials should be obtained for laboratory testing. The tests will provide a basis for evaluation of fill compaction by in- place density testing. A qualified soil technician should perform sufficient in-place density tests during the filling operations to evaluate that proper levels of compaction, including dry unit weight and moisture content, are being attained. 2. Imported select fill should consist of crushed limestone base material meeting the requirements of the Texas Department of Transportation (TxDOT) 2004 Standard Specifications Item 247, Type A, Grade 3, or a low-plasticity coarse-grained soil with a plasticity index between 7 and 20 percent, a maximum gravel content (percentage retained on No. 4 sieve) of 40 percent, and rocks no larger than 4 inches in their largest dimension. As an alternative, a low-plasticity granular fill material which does not meet these specifications may be used only if approved by Terracon.

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3. Based on the laboratory testing performed during this exploration, the on-site Stratum I soils are not suitable for re-use as select fill. Portions of the Stratum II lean clay soils may be suitable for re-use as select fill if the PI is less than 20; however, before the final determination can be made as to whether or not the material is acceptable, the excavated material should be separated from organics and debris and stockpiled for further laboratory testing in order to confirm its suitability for re-use as select fill. 4. Excavated on-site soils, if free of organics, debris, and rocks larger than 4 inches, may be considered for use as fill in pavement, landscape, or other general areas. For economic reasons, expansive soils are often used in pavement and/or flatwork areas. The owner should be aware that the risk exists for future movements of the subgrade soils which may result in movement and/or cracking of pavements and/or flatwork.

4.2.1 Compaction Requirements Recommended compaction and moisture content criteria for engineered fill materials are as follows:

BENEATH FOUNDATIONS, SLAB, AND ALL ASSOCIATED FLATWORK AREAS DEFINED AS BUILDING AREA LIMITS Per the Standard Proctor Test (ASTM D 698) Range of Moisture Contents for Material Type and Location Minimum Compaction Compaction Requirement (%) Minimum Maximum Crushed Limestone Base 95 1 -3% +3% Imported Select Fill 95 1 -3% +3% Stratum II Soils 95 -3% +3% Moisture Conditioned Stratum I Building Pad 93 +2% +6% Clays 1. For fills greater than 5 feet in depth, the compaction should be increased to at least 100 percent of the ASTM D 698 maximum dry density.

BENEATH PAVEMENTS AND OTHER NON-STRUCTURAL AREAS OF THE SITE Per the Standard Proctor Test (ASTM D 698) Range of Moisture Contents for Material Type and Location Minimum Compaction Compaction Requirement (%) Minimum Maximum Paving Fill with PI<20 95 -3% +3% Paving Fill with PI≥20 and Subgrade 95 Optimum +4%

Responsive ■ Resourceful ■ Reliable 7 Geotechnical Engineering Report Oertli Multifamily ■ Austin, Texas November 21, 2014 ■ Terracon Project No. 96145207

Per the Standard Proctor Test (ASTM D 698) Range of Moisture Contents for Material Type and Location Minimum Compaction Compaction Requirement (%) Minimum Maximum Crushed Limestone Base (beneath 95 1 -3% +3% pavements) 1. Per the Modified Proctor Test (ASTM D 1557).

Engineered fill materials should be placed in horizontal, loose lifts not exceeding 8 inches in thickness and should be thoroughly compacted. Where light compaction equipment is used, as is customary within a few feet of retaining walls and in utility trenches, the lift thickness may need to be reduced to achieve the desired degree of compaction.

We recommend that engineered fill be tested for moisture content and compaction during placement. Should the results of the in-place density tests indicate the specified moisture or compaction limits have not been met, the area represented by the test should be reworked and retested as required until the specified moisture and compaction requirements are achieved.

4.2.2 Grading and Drainage The performance of the foundation systems for the proposed structures will not only be dependent upon the quality of construction, but also upon the stability of the moisture content of the near- surface soils. Therefore, we highly recommend that site drainage be developed so that ponding of surface runoff near the structures does not occur. Accumulation of water near the structure’s foundations may cause significant moisture variations in the soils adjacent to the foundations, thus increasing the potential for structural distress.

Positive drainage away from the structures must be provided during construction and maintained through the life of the proposed project. Infiltration of water into excavations should be prevented during construction. It is important that foundation soils are not allowed to become wetted. All grades must provide effective drainage away from the structures during and after construction. Exposed (unpaved) ground should be sloped at a minimum 5 percent away from the structures for at least 10 feet beyond the perimeter of the structures. Water permitted to pond next to the structures can result in greater soil movements than those discussed in this report. Estimated movements described in this report are based on effective drainage for the life of the structures and cannot be relied upon if effective drainage is not maintained.

Roof runoff and surface drainage should be collected and discharged away from the structures to prevent wetting of the foundation soils. Roof gutters should be installed and connected to downspouts and pipes directing roof runoff at least 10 feet away from the structures, or discharged on to positively sloped pavements.

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If irrigation is planned, sprinkler mains and spray heads should preferably be located at least 5 feet away from the structures such that they cannot become a potential point source of water directly adjacent to the structures. In addition, the owner and/or builder should be made aware that placing large bushes and trees adjacent to the structures may cause significant moisture variations in the soils underlying the structures. In general, tree roots can adversely influence the subsurface soil moisture content to a distance of 1 to 1½ times the mature height of the tree and beyond the tree canopy. Watering of vegetation should be performed in a timely and controlled manner and prolonged watering should be avoided. Landscaped irrigation adjacent to the foundation units should be minimized or eliminated. Special care should be taken such that underground utilities do not develop leaks with time.

4.2.3 Utility Trench Plugs Utility trenches are a common source of water infiltration and migration. All utility trenches that penetrate beneath the buildings should be effectively sealed to restrict water intrusion and flow through the trenches that could migrate below the buildings. We recommend constructing an effective clay or flowable fill “trench plug” that extends at least 2 feet out from the face of the building exterior. The clay fill/flowable fill should be placed to completely surround the utility line and it should fill the utility trench completely in width and height, with the exception of topsoil at the surface. If clay plug is used, it should be fat clay with a minimum PI of 30 and should be compacted in accordance with recommendations in Section 4.2.1. If flowable fill is used, it should be in accordance with TxDOT Item 401.

4.3 Floor Slab Subgrade Preparation

As mentioned previously, the soils at this site exhibit a PVR of up to about 3½ inches. A common method of subgrade preparation to reduce potential expansion of the subgrade would be to remove a portion of the expansive Stratum I clay soils and provide a pad of properly placed and compacted select fill, in conjunction with moisture conditioned clays, beneath the floor slabs. The corresponding decrease in the potential soil movement is primarily a function of the fill pad thickness and the moisture levels of the underlying clay subgrade. While the indicated preparations do not eliminate the potential for soil movement, the magnitude of such movements may be reduced to more conventional and acceptable levels.

For the proposed apartment buildings, we recommend that the near-surface soils be prepared as stated below to reduce the potential for foundation movements associated with volumetric changes of the underlying clay soils. Typically, the subgrade within the building areas are prepared to reduce the maximum estimated PVR to about one inch or less. The subgrade preparation options presented below should reduce post-construction floor slab movements to about one inch.

Please note that at the time of this report, no proposed site grading plan or finished floor elevations had been provided to us. The following building pad preparation recommendations assume

Responsive ■ Resourceful ■ Reliable 9 Geotechnical Engineering Report Oertli Multifamily ■ Austin, Texas November 21, 2014 ■ Terracon Project No. 96145207 maximum cuts or fills of up to 2 feet. If larger cuts or fills are necessary, Terracon should be contacted to either confirm or modify the recommendations included in this report.

BUILDINGS 1, 4, 5, 6, 7, 10, 11 & 12 Minimum Material Thickness (feet) 1 Component Option 1 Option 2 Select Fill 4 3 Moisture Conditioned Subgrade 2 4 Minimum Total Thickness 6 7 1. If the Stratum II lean clay soils are encountered within the indicated select fill or moisture conditioning depth, excavation may be ceased as it is not necessary to excavate any deeper into the Stratum II clays. The moisture conditioned clay thickness should be reduced first. If Stratum II is encountered at very shallow depths compared to final grade, a minimum of 2 feet of select fill soil should be provided within all portions of the building areas.

BUILDINGS 2, 3, 8, 9 & CLUBHOUSE/LEASING OFFICE Minimum Material Thickness (feet) 1 Component Option 1 Option 2 Select Fill 4 3 Moisture Conditioned Subgrade ½ 2 Minimum Total Thickness 4½ 5 1. If the Stratum II lean clay soils are encountered within the indicated select fill or moisture conditioning depth, excavation may be ceased as it is not necessary to excavate any deeper into the Stratum II clays. The moisture conditioned clay thickness should be reduced first. If Stratum II is encountered at very shallow depths compared to final grade, a minimum of 2 feet of select fill soil should be provided within all portions of the building areas.

With each alternative, the indicated thickness of moisture conditioned subgrade soils after removal of on-site soils should be moisture conditioned to between +2 and +6 percent of optimum moisture content and compacted to ≥93 percent of the Standard Proctor (ASTM D 698) maximum dry density. Upon completion of moisture conditioning and compacting of exposed soils, properly compacted select fill should be placed and compacted within the building areas as indicated in the tables above for the selected options. No less than the above indicated thickness of select fill soil should be provided in the building pad areas. With these preparation options, post- construction floor slab movements should be on the order of about 1-inch. Due to the multiple options, we suggest that the option performed under each building be noted on the final as-built set of plans for final documentation purposes.

Water added to the clays in the moisture conditioning process may need to soak into the soils at least overnight prior to compaction to achieve a uniform moisture level within the clay soils. The clay soils may become difficult to handle and compact and may present construction equipment access difficulties at the moisture levels described above. The contractor should also provide

Responsive ■ Resourceful ■ Reliable 10 Geotechnical Engineering Report Oertli Multifamily ■ Austin, Texas November 21, 2014 ■ Terracon Project No. 96145207 appropriate equipment to achieve the proper level of compaction at the moisture levels indicated above. This should reduce the swell potential of these soils, in addition to reducing their permeability, which should help to protect the underlying clay subgrade from changes in moisture content.

Prior to moisture conditioning of the subgrade, it should be thoroughly proofrolled with a 20-ton roller to detect weak zones in the subgrade as discussed in Section 4.2 – Earthwork. Then, prior to placement and compaction of select fill, the soil subgrade should be scarified, moisture adjusted, and compacted as given above. All fill material placed within the building footprint should meet the requirements of Select Fill described in Section 4.2 – Earthwork. The above subgrade preparation recommendations should be applied to an area extending a minimum of 5 feet outside of building and canopy areas, including attached walkways, ramps, swimming pool areas, pool decks, garages, and any other architectural members. Material and placement requirements for select fill, as well as other subgrade preparation recommendations, are presented in Section 4.2 – Earthwork. We suggest the use of crushed limestone base as the select fill material within the upper 6 inches of the fill pad from a standpoint of construction access during wet weather, as well as from a standpoint of floor slab support.

Flatwork will be subject to post-construction movements also. For any flatwork (sidewalks, ramps, etc.) outside of the building areas which will be sensitive to movement, subgrade preparation as discussed above should be considered to reduce differential movements between the flatwork and the adjacent building. If subgrade preparation as given above for building areas is not implemented in the exterior flatwork areas, those areas may be susceptible to post-construction movements (up to about 3½ inches) as discussed above for in-situ soil conditions.

We should also note that the potential movement values indicated are based upon moisture variations in the subgrade due to circumstances such as moisture increases due to rainfall and loss of evapotranspiration. In circumstances where significant water infiltration beneath the floor slab occurs (such as a leaking utility line or water seepage from outside the building resulting from poor drainage), movements in isolated floor slab areas could potentially be in excess of those indicated in this report.

4.4 Foundation System

As mentioned in Section 4.1 – Geotechnical Considerations, it is our opinion that monolithic slab-on-grade foundation systems would be appropriate to support the proposed multi-family apartment buildings provided the subgrade for the buildings are prepared to reduce the shrink/swell potential of the subgrade to more tolerable levels. Recommendations for this type of foundation system are presented in the following subsections along with other geotechnical engineering considerations for this project.

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4.4.1 Design Recommendations – Monolithic Slab-On-Grade A monolithic slab-on-grade foundation system (either conventionally reinforced or post-tensioned) would be appropriate to support the multi-family apartment buildings provided subgrade preparation as described in Section 4.3 – Floor Slab Subgrade Preparation is followed.

The slab foundation design parameters presented in the following tables are based on the criteria published by the Building Research Advisory Board (BRAB), the Prestressed Concrete Institute (PCI), the Wire Reinforcement Institute (WRI), and the Post-Tensioning Institute (PTI) 3rd Edition. These are essentially empirical design methods and the recommended design parameters are based on our understanding of the proposed project, our interpretation of the information and data collected as a part of this study, our area experience, and the criteria published in the BRAB, PCI, WRI, and PTI design manuals.

Conventional Slab and Beam System Parameters for Subgrade Prepared as in Section 4.3 Minimum embedment of grade beams below final 24 inches grade1 Net dead plus sustained live load – 1,700 psf Bearing Pressures (allowable) 2 Net total load – 2,500 psf 150 pci if on crushed limestone base Subgrade Modulus (k) 3 100 pci if on alternative select fill Approximate Potential Vertical Rise (PVR) About 1-inch 4 1. Embedment is to reduce surface water migration below the foundation elements and to develop proper end bearing and is not based on structural considerations. The grade beam width and depth should be properly evaluated by the structural engineer. Grade beams may be thickened and widened at interior column locations to serve as spread footings at these concentrated load areas. 2. Grade beams may bear on properly compacted imported select fill soils. 3. Several design methods use the modulus of subgrade reaction, k, to account for soil properties in design of flat, floor slabs. The modulus of subgrade reaction is a spring constant that depends on the kind of soil, the degree of compaction, and the moisture content. Based on our recommendations provided in Section 4.3, the above indicated subgrade modulus can be used for design of a flat, grade-supported floor slab. 4. Differential movements may result from variances in subsurface conditions, loading conditions and construction procedures. We recommend that measures be taken whenever practical to increase the tolerance of the building to post-construction foundation movements. An example of such measures would be to provide frequent control joints for exterior masonry veneers and interior sheetrock walls (particularly near doors and windows) to control cracking across such walls and concentrate movement along the joints.

BRAB/WRI/PCI Parameters for Subgrade Prepared as in Section 4.3 Design Plasticity Index (PI) 1, 2 28

Climatic Rating (Cw) 17

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BRAB/WRI/PCI Parameters for Subgrade Prepared as in Section 4.3 Unconfined Compressive Strength 2 1.0 tsf Soil Support Index (C) for BRAB 2 0.86 1. The BRAB effective PI is equal to the near surface PI if that PI is greater than all of the PI values in the upper 15 feet; otherwise it is the weighted average of the PI values in the upper 15 feet. The WRI/PCI effective PI is always the weighted average of the PI values in the upper 15 feet. 2. For subgrade prepared as in Section 4.4.

Post Tensioning Institute (PTI) Parameters for Subgrade Prepared as in Section 4.3 1 Depth of Seasonal Moisture Change 2 Up to 15 feet Select fill – 15 Plasticity Index 3 Stratum I soils – 31 to 51 Stratum II soils – 12 to 29 Select fill – 25 (estimated) Percent Finer than 2 Microns 3 Stratum I soils – 60 to 80 (estimated) Stratum II soils – 37 to 40 Soil Fabric Factor 1.0 Approximate Thornthwaite Moisture Index -12 Estimated Constant Soil Suction 3.5 pF Range of Soil Suction 3.0 to 4.5 pF Center Lift 8.3 feet 4, 5, 6 Edge Moisture Variation Distance, em Edge Lift 4.2 feet Center Lift 1.0-inch 5, 6 Differential Soil Movement, ym (Center Lift) Edge Lift 1.3 inches 1. Based on our analysis of the field and laboratory data, design parameters were computed using the Addendum to the 2004 Post-Tensioning Institute (PTI) method2 for slab-on-grade design and the subsequent Errata to the Addendum approved by the PTI Slab-on-Grade Committee on February 7, 2008. 2. The moisture beneath a shallow foundation will change in response to wetting and drying conditions around the foundation perimeter. The moisture condition has a significant effect on slab behavior and is highly variable with time, changing seasonally, with annual climate conditions, drainage patterns, ground cover, and vegetation (trees and shrubs). 3. The plasticity index and the clay mineral percentage are values of the soil that can be estimated by laboratory tests, and, although variable from location to location, remain relatively constant with time.

4. The maximum moisture variation distance is termed the edge moisture variation distance, e m, and is an important factor governing the design of post-tensioned floor slabs. The e m is related to percent fine clay

2. Post-Tensioning Institute, “Addendum No. 1 to the 3rd Edition of the Design of Post-Tensioned Slabs-on- Ground”, Post-Tensioning Institute, Phoenix, AZ, May 2007.

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and climatic conditions as well as other parameters, such as soil fabric factor and unsaturated diffusion coefficient.

5. The differential movements, ym, and edge moisture variation distances, em, were calculated by modeling soil profiles using the commercial software program VOLFLO as recommended by the PTI manual. 6. For subgrade prepared as in Section 4.4.

If slab-on-grade foundations are used, we recommend that measures be taken whenever practical to increase the tolerance of the buildings to post-construction foundation movements. An example of such measures would be to provide frequent control joints for rock/masonry veneer exteriors to control cracking across such walls and concentrate movements along the joints.

For a slab foundation system designed and constructed as recommended in this report, post- construction settlements should be less than 1-inch. Settlement response of a select fill supported slab is influenced more by the quality of construction than by soil-structure interaction. Therefore, it is essential that the recommendations for foundation construction be strictly followed during the construction phases of the building pad and foundation.

The use of a vapor retarder should be considered beneath concrete slabs-on-grade that will be covered with wood, tile, carpet or other moisture-sensitive or impervious coverings, or when the slabs will support equipment sensitive to moisture. When conditions warrant the use of a vapor retarder, the slab designer and slab contractor should refer to ACI 302 for procedures and cautions about the use and placement of a vapor retarder.

4.4.2 Foundation Construction Considerations Slab-on-Grade Grade beams and footings should be neat excavated if possible. If neat excavation is not possible, the foundation should be properly formed. If a toothed bucket is used, excavation with this bucket should be stopped approximately 6 inches above final grade and the grade beam/footing excavation completed with a smooth-mouthed bucket or by hand labor. Debris in the bottom of the excavation should be removed prior to steel placement. The foundation excavation should be sloped sufficiently to create internal sumps for runoff collection and removal. If surface runoff water or groundwater seepage in excess of one inch accumulates at the bottom of the foundation excavation, it should be collected, removed, and not allowed to adversely affect the quality of the bearing surface.

If used, the post-tensioned slab-on-grade construction technique should be carefully monitored by qualified personnel. The sophistication of this construction procedure requires careful attention to details such as concrete integrity and anchorages, along with tendon spacing, support, covering, and stressing. Poor construction could result in a non-functional slab foundation system.

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Foundation Construction Monitoring The performance of the foundation systems for the proposed structures will be highly dependent upon the quality of construction. Thus, we recommend that the foundation installation be monitored by Terracon to identify the proper bearing strata and depths and to help evaluate foundation construction. We would be pleased to develop a plan for foundation monitoring to be incorporated in the overall quality control program.

4.5 Seismic Design Information

Seismic Design Code Used Site Classification Category 2012 International Building Code (IBC) A1 D2 1. Per IBC 2012 Section 1613.3.1. 2. Per IBC 2012 Table 1613.3.2. The 2012 IBC requires a site soil profile determination extending a depth of 100 feet for seismic site classification. The current scope does not include the required 100- foot soil profile determination. Borings extended to a maximum depth of approximately 15 feet and this seismic site class definition assumes that materials with similar characteristics are below the maximum depth of the subsurface exploration. Additional exploration to deeper depths would be required to confirm the conditions below the current depth of exploration. Alternatively, a geophysical exploration could be used in order to attempt to justify a higher seismic class. If you desire parameters for earlier versions of IBC, please contact us. Ground Motion Parameter Value (g)1

Ss 0.064

S1 0.034

SMS 0.102

SM1 0.082

SDS 0.068

SD1 0.055 1. Site Latitude 30.39375°N and Longitude 97.65144°W.

4.6 Lateral Earth Pressures

Presented below are at-rest, active, and passive earth pressure coefficients for various backfill types adjacent to below-grade walls or site retaining walls. At-rest earth pressures are recommended in cases where little wall yield is expected (such as structural below-grade walls). Active earth pressures may be used in cases where the walls can exhibit a certain degree of horizontal movement (such as cantilevered retaining walls). The recommendations in this section apply to those walls which are installed in open cut or embankment fill areas such that the backfill extends out from the base of the wall at an angle of at least 45 degrees from vertical for the entire height and length of the wall.

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Estimated Lateral Earth Pressure Coefficients1 Backfill Type Total Unit Weight (pcf) At Rest (KO) Active (KA) Passive (KP) Crushed Limestone 140 0.45 0.3 3.5 Clean Sand 120 0.5 0.35 3.0 Clean Gravel 120 0.45 0.3 3.5 1. Coefficients represent ultimate values. Appropriate safety factors should be applied.

The above values do not include a hydrostatic or ground-level surcharge component. To prevent hydrostatic pressure build-up, retaining walls should incorporate functional drainage (via free- draining aggregate or manufactured drainage mats) within the backfill zone. The effect of surcharge loads, where applicable, should be incorporated into wall pressure diagrams by adding a uniform horizontal pressure component equal to the applicable lateral earth pressure coefficient times the surcharge load, applied to the full height of the wall.

The compactive effort should be controlled during backfill operations adjacent to walls. Overcompaction can produce lateral earth pressures in excess of at-rest magnitudes. Compaction levels adjacent to walls should be maintained between 95 and 100 percent of Standard Proctor (ASTM D 698) maximum dry density.

For retaining walls bearing at least 2 feet below existing grades on on-site soils, we recommend a coefficient of sliding resistance of 0.4 (maximum allowable sliding resistance of 500 psf) and a maximum footing bearing capacity of 2,500 psf. All retaining walls should be checked against failure due to overturning, sliding, and overall slope stability. Such an analysis can only be performed once the dimensions of the wall and cut/fill scenarios are known. Retaining walls placed to bear upon the highly expansive Stratum I fat clays observed on this site will be subject to the potential movements described previously (up to about 3½ inches).

We recommend that a buffer area of at least 5 feet for all pavement areas be placed between retaining walls (with a minimum height of 4 feet or more), and the adjacent construction. In building areas, this buffer zone from retaining walls should be increased to at least 10 feet. These recommended buffer zones are to reduce the potential of distress from any long-term (“creep”) movements of the wall and backfill. Pedestrian sidewalks may be exempted from the above criteria; however, some distress could still be observed in the sidewalks due to movements of the retaining walls and backfill.

A wall drain (consisting of freely-draining aggregate or manufactured drainage mat, along with outlet piping) is recommended for collection and removal of surface water percolation behind the walls. Proper control of surface water percolation will help to prevent buildup of higher wall pressures. In unpaved areas, the final 12 inches of backfill should preferably consist of clayey soils to help to reduce percolation of surface water into the backfill.

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4.7 Pavements

Both flexible (asphaltic concrete) and rigid (reinforced Portland cement concrete) pavement systems may be considered for site pavement applications. These two types of pavement are not considered equal. Over the life of the pavement, concrete pavements would be expected to exhibit better performance and require less maintenance.

Detailed traffic loads and frequencies were not available for the pavements. However, we anticipate that traffic will consist primarily of passenger vehicles in the parking areas (assumed as the light duty pavements) and passenger vehicles combined with occasional garbage and delivery/moving trucks in driveways (assumed as light-medium duty pavements). If heavier traffic loading is expected or other traffic information is available, Terracon should be provided with the information and allowed to review the pavement sections provided herein. Tabulated below are the assumed traffic frequencies and loads used to design pavement sections for this project.

Pavement Type Traffic Design Index Description Light traffic – Few vehicles heavier than Parking Areas passenger cars, panel, and pick-up trucks; no (Passenger Vehicles DI-1 regular use by heavily loaded two-axle trucks or Only): lightly loaded larger vehicles. (EAL* < 5) Light to medium traffic – Similar to DI-1, Driveways and including not over 50 heavily loaded two-axle Dumpster Enclosures DI-2 trucks or lightly loaded larger vehicles per day. (Light-Medium Duty): No regular use by heavily loaded trucks with three or more axles. (EAL = 6 – 20) * Equivalent daily 18-kip single axle load applications.

Listed below are pavement component thicknesses which may be used as a guide for pavement systems at the site assuming that the on-site soils will generally act as the pavement subgrade, and that the pavement subgrade is prepared as outlined in the “Moisture Conditioned Subgrade” portions of this section and in accordance with our general recommendations for site preparation in Section 4.2 – Earthwork. We should note that these systems were derived based on general characterization of the subgrade. No specific testing (such as CBR, resilient modulus tests, etc.) was performed for this project to evaluate the support characteristics of the subgrade.

FLEXIBLE PAVEMENT SYSTEM Material Thickness (Inches) Component DI-1 DI-2 Asphaltic Concrete (HMAC) 2.0 2.5 Crushed Limestone Base 9.0 10.0 Moisture Conditioned Subgrade 6.0 6.0

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RIGID PAVEMENT SYSTEM Material Thickness (Inches) Component DI-1 DI-2 Reinforced Concrete 5.0 6.0 Moisture Conditioned Subgrade 6.0 6.0 1 1. Dumpster pads should be constructed with 7 inches of concrete over moisture conditioned subgrade.

Reinforcing Steel: #3 bars spaced at 18 inches on centers in both directions.

Control Joint Spacing: In accordance with ACI 330R-08, control joints should be spaced no greater than 12.5 feet for 5-inch thick concrete and no greater than 15 feet for 6-inch thick or greater concrete. If sawcut, control joints should be cut within 6 to 12 hours of concrete placement. Sawcut joints should be at least ¼ of the slab thickness.

Expansion Joint Spacing: ACI 330R-08 indicates that regularly spaced expansion joints may be deleted from concrete pavements. Therefore, the installation of expansion joints is optional and should be evaluated by the design/construction team. Expansion joints, if not sealed and maintained, can allow infiltration of surface water into the subgrade.

Dowels at Expansion Joints: ¾-inch smooth bars, 18 inches in length, with one end treated to slip, spaced at 12 inches on centers at each joint.

Presented below are our recommended material requirements for the various pavement sections.

Hot Mix Asphaltic Concrete (HMAC) – The asphaltic concrete surface course should be plant mixed, hot laid Type D (Fine-Graded Surface Course) meeting the master specification requirements in TxDOT Item 340 or City of Austin (COA) Item 340. For acceptance and payment evaluation purposes, we suggest considering the use of the provisions in COA Item 340.

Reinforced Portland Cement Concrete (PCC) – Concrete should be designed to exhibit a flexural strength (third-point loading) of at least 500 psi at 28 days. As an option, a 28-day compressive strength of 3,500 psi may be used.

Crushed Limestone Base – Base material should be composed of crushed limestone meeting the requirements of TxDOT Item 247, Type A, Grade 1 or COA Item 210. The base should be compacted to a minimum of 95 percent of the maximum density as

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determined by the modified moisture/density relation (ASTM D 1557) at -3 to +3 percent of optimum moisture content. (As an option, compaction to at least 100 percent of the TEX-113-E maximum dry density may also be considered.) Each lift of base should be thoroughly proofrolled just prior to placement of subsequent lifts and/or asphalt. Particular attention should be paid to areas along curbs and adjacent to landscape islands and storm drain inlets. Placement of the base material should extend at least 12 inches behind curbs.

Moisture Conditioned Subgrade – The soil subgrade should be scarified to a depth of 6 inches, moisture conditioned, and recompacted to at least 95 percent of the maximum dry density as determined by ASTM D 698. Select fill and on-site soils should be moisture conditioned and compacted as described in Section 4.2.1 – Compaction Requirements. Care should be taken such that the subgrade does not dry out or become saturated prior to pavement construction. The pavement subgrade should be thoroughly proofrolled with a rubber-tired vehicle (fully loaded water or dump truck) immediately prior placement of base material. Particular attention should be paid to areas along curbs and adjacent to landscape islands and storm drain inlets. Placement of the moisture conditioned subgrade should extend at least 18 inches behind curbs.

Pavement design methods are intended to provide structural sections with adequate thickness over a particular subgrade such that wheel loads are reduced to a level the subgrade can support. The support characteristics of the subgrade for pavement design do not account for shrink/swell movements of an expansive clayey subgrade. Thus, the pavement may be adequate from a structural standpoint, yet still experience cracking and deformation due to shrink/swell related movement of the subgrade. It is, therefore, important to minimize moisture changes in the subgrade to reduce shrink/swell movements. Proper perimeter drainage should be provided so that infiltration of surface water from unpaved areas surrounding the pavement is minimized.

On most projects, rough site grading is accomplished relatively early in the construction phase. Fills are placed and compacted in a uniform manner. However, as construction proceeds, excavations are made into these areas; dry weather may desiccate some areas; rainfall and surface water saturates some areas; heavy traffic from concrete and other delivery vehicles disturbs the subgrade; and many surface irregularities are filled in with loose soils to temporarily improve subgrade conditions. As a result, the pavement subgrade should be carefully evaluated as the time for pavement construction approaches. This is particularly important in and around utility trench cuts. All pavement areas should be moisture conditioned and properly compacted to the recommendations in this report immediately prior to paving. Thorough proofrolling of pavement areas using a fully-loaded water truck or dump truck (rubber-wheeled vehicle that can impart point wheel loads) should be performed no more than 36 hours prior to surface paving. Any problematic areas should be reworked and compacted at that time.

Openings in pavement, such as landscape islands, are sources for water infiltration into surrounding pavements. Water collects in the islands and migrates into the surrounding base

Responsive ■ Resourceful ■ Reliable 19 Geotechnical Engineering Report Oertli Multifamily ■ Austin, Texas November 21, 2014 ■ Terracon Project No. 96145207 material and subgrade soils thereby degrading support of the pavement. The civil design for the pavements should include features to restrict or to collect and discharge excess water from the islands. Examples of features are self-contained planters, edge drains connected to the storm water collection system or other suitable outlet, and impermeable barriers preventing lateral migration of water such as a cutoff wall installed to a depth below the pavement structure.

Long-term pavement performance will be dependent upon several factors, including maintaining subgrade moisture levels and providing for preventive maintenance. The following recommendations should be considered at a minimum:

n Adjacent site grading at a minimum 2% grade away from the pavements; n A minimum ¼ inch per foot slope on the pavement surface to promote proper surface drainage; n Install joint sealant and seal cracks immediately; n Placing compacted, low permeability clay backfill against the exterior side of curb and gutter; and, n Placing curb and gutters through any base material and directly on subgrade soils.

Preventive maintenance should be planned and provided for through an on-going pavement management program. These activities are intended to slow the rate of pavement deterioration and to preserve the pavement investment. Preventive maintenance consists of both localized maintenance (e.g. crack and joint sealing and patching) and global maintenance. This is usually the first priority when implementing a planned pavement maintenance program and provides the highest return on investment for pavements. Prior to implementing any maintenance, additional engineering observation is recommended to determine the type and extent of preventive maintenance.

5.0 GENERAL COMMENTS

Terracon should be retained to review the final design plans and specifications so comments can be made regarding interpretation and implementation of our geotechnical recommendations in the design and specifications. Terracon also should be retained to provide testing and observation during excavation, grading, foundation installation, and other construction phases of the project.

The analysis and recommendations presented in this report are based upon the data obtained from the borings performed at the indicated locations and from other information discussed in this report. This report does not reflect variations that may occur between borings, across the site, or due to the modifying effects of weather. The nature and extent of such variations may not become evident until during or after construction. If variations appear, we should be immediately notified so that further evaluation and supplemental recommendations can be provided.

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The scope of services for this project does not include, either specifically or by implication, any environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention of pollutants, hazardous materials, or conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be undertaken.

For any excavation construction activities at this site, all Occupational Safety and Health Administration (OSHA) guidelines and directives should be followed by the Contractor during construction to provide a safe working environment. In regards to worker safety, OSHA Safety and Health Standards require the protection of workers from excavation instability in trench situations.

This report has been prepared for the exclusive use of our client for specific application to the project discussed and has been prepared in accordance with generally accepted geotechnical engineering practices. No warranties, either express or implied, are intended or made. Site safety, excavation support, and dewatering requirements are the responsibility of others. In the event that changes in the nature, design, or location of the project as outlined in this report are planned, the conclusions and recommendations contained in this report shall not be considered valid unless Terracon reviews the changes and either verifies or modifies the conclusions of this report in writing.

Responsive ■ Resourceful ■ Reliable 21 APPENDIX A FIELD EXPLORATION SITE

DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES.

Project Manager: Project No. EXHIBIT ADK 96145207 SITE VICINITY MAP Drawn By: Scale: ADK N.T.S. OERTLI MULTIFAMILY Checked By: File Name: ADK 96145207 E. PARMER LANE, NW OF DESSAU ROAD A-1 Approved By: Date: 5307 Industrial Oaks Blvd, Suite 160 Austin, Texas 78735 AUSTIN, TEXAS ADK 11/14/2014 PH. (512) 442-1122 FAX. (512) 442-1181 B-3 B-4 8 9 B-2 1

B-8 B-7 B-1 B-6 10

2 7 11 B-5 B-10 B-11 3

4 6 B-9 12 B-12 B-13

5

DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES

Project Manager: Project No. EXHIBIT ADK 96145207 BORING LOCATION PLAN Drawn By: Scale: ADK N.T.S. OERTLI MULTIFAMILY Checked By: File Name: ADK 9615207 E. PARMER LANE, NW OF DESSAU ROAD A-2 Approved By: Date: 5307 Industrial Oaks Blvd, Suite 160 Austin, Texas 78735 AUSTIN, TEXAS ADK 11/14/2014 PH. (512) 442-1122 FAX. (512) 442-1181 B-2 B-1

B-3

B-6 B-4

B-5 B-7 B-8

B-9 B-11 B-10

B-12 Inaccessible at the time of our field program.

DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES. BORING LOCATIONS AND SITE BOUNDARY ARE APPROXIMATE.

Project Manager: Project No. EXHIBIT ADK 96145207 BORING LOCATION AERIAL Drawn By: Scale: ADK AS SHOWN OERTLI MULTIFAMILY Checked By: File Name: ADK 9615207 E. PARMER LANE, NW OF DESSAU ROAD A-3 Approved By: Date: 5307 Industrial Oaks Blvd, Suite 160 Austin, Texas 78735 AUSTIN, TEXAS ADK 11/14/2014 PH. (512) 442-1122 FAX. (512) 442-1181 Geotechnical Engineering Report Oertli Multifamily ■ Austin, Texas ■ Terracon Project No. 96145207 November 21, 2014 ■ Terracon Project No. 96145207

Field Exploration Description

Subsurface conditions were evaluated by drilling thirteen borings to depths of about 15 feet within the proposed building areas. The borings were drilled with truck-mounted rotary drilling equipment at the approximate locations shown on Exhibits A-2 and A-3 of Appendix A. Boring depths were measured from the existing ground surface at the time of our field activities. The boring coordinates were located in the field through the use of a Garmin handheld GPS unit. The coordinates are presented on the top of the boring logs. Elevations were approximated based on the site topography survey provided to us.

The boring logs, which include the subsurface descriptions, types of sampling used, and additional field data for this study, are presented on the boring logs in Appendix A. Criteria defining terms, abbreviations and descriptions used on the boring logs are presented in Appendix C.

When possible, surficial soil samples were generally recovered using thin-walled, open-tube samplers (Shelby tubes). A pocket penetrometer test was performed on each sample of cohesive soil in the field to serve as a general measure of consistency.

Soils for which good quality tube samples could not be obtained were sampled by means of the Standard Penetration Test (SPT). This test consists of measuring the number of blows required for a 140-pound hammer free falling 30 inches to drive a standard split-spoon sampler 12 inches into the subsurface material after being seated 6 inches. This blow count or SPT “N” value is used to estimate the engineering properties of the stratum. A CME automatic SPT hammer was used to advance the split-barrel sampler in the borings performed on this site. A greater efficiency is typically achieved with the automatic hammer compared to the conventional safety hammer operated with a cathead and rope. Published correlations between the SPT values and soil properties are based on the lower efficiency cathead and rope method. This higher efficiency affects the standard penetration resistance blow count (N) value by increasing the penetration per hammer blow over what would be obtained using the cathead and rope method. The effect of the automatic hammer's efficiency has been considered in the interpretation and analysis of the subsurface information for this report.

Samples were removed from the samplers in the field, visually classified, and appropriately sealed in sample containers to preserve the in-situ moisture contents. Samples were then placed in core boxes for transportation to our laboratory in Austin, Texas.

Exhibit A-4 BORING LOG NO. B-1 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Clubhouse STRENGTH TEST LIMITS

Latitude: 30.394332° Longitude: -97.65291° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 715 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), dark brown, very stiff

3.5 tsf (HP) 18

2.0 713+/- LEAN CLAY (CL), grayish-brown in the upper 2 feet, pale brown to light gray to light brownish-gray to yellow below about 2 feet, very stiff to hard, blocky, marly, 4.5 tsf (HP) UC 3.98 7.8 17 107 with trace shell fragments

5 4.5 tsf (HP) 0.6 12 123 38-16-22

4.5 tsf (HP) 14 120

14-20-22 15 N=42 10

with ferrous partings below about 13 feet

4.5 tsf (HP)

15.0 700+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-5 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 BORING LOG NO. B-2 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Building 1 STRENGTH TEST LIMITS

Latitude: 30.394382° Longitude: -97.652122° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 712 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), trace gravel, dark brown, stiff 1.5 tsf (HP) UC 1.71 5.3 32 86

1.5 tsf (HP) 33 70-21-49

4.0 708+/- FAT CLAY (CH), pale brown to light gray to light brownish-gray to yellow, hard, blocky, marly 5 4.5 tsf (HP) 20

4.5 tsf (HP) 23 50-21-29

8.0 704+/- LEAN CLAY (CL), pale brown to light gray to light brownish-gray to yellow, hard, blocky, marly 13-28-30 with ferrous partings below about 9 feet 15 N=58 10

4.5 tsf (HP)

15.0 697+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-6 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 BORING LOG NO. B-3 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Building 8 STRENGTH TEST LIMITS

Latitude: 30.394153° Longitude: -97.650939° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 713 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), trace gravel, dark brown, stiff 2.5 tsf (HP) UC 1.46 5.2 35 83

3.0 tsf (HP) 27

4.0 709+/- LEAN CLAY (CL), trace sand and gravel, pale brown to light gray to light brownish-gray to yellow, hard, blocky, marly 5 4.5 tsf (HP) 18 31-18-13 87

9-14-16 with ferrous partings below about 7 feet 15 N=30

10-24-27 18 N=51 10

24-37-33 N=70 15.0 698+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-7 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 BORING LOG NO. B-4 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Building 9 STRENGTH TEST LIMITS

Latitude: 30.393915° Longitude: -97.650463° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 718.5 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), dark brown, hard

4.5 tsf (HP) UC 6.53 4.4 24 99

3.0 715.5+/- 4.5 tsf (HP) 21 LEAN CLAY (CL), pale brown to light gray to light brownish-gray to yellow, hard, blocky, marly

10-28-38 10 5 N=66

23-44-31 13 38-18-20 N=75

4.5 tsf (HP) 14 120

10

15-21-28 N=49 15.0 703.5+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-8 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 BORING LOG NO. B-5 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Building 3 STRENGTH TEST LIMITS

Latitude: 30.393836° Longitude: -97.652774° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 713.5 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), dark brown, very stiff to hard 3.5 tsf (HP) 23

4.5 tsf (HP) UC 9.90 13 16 112 51-20-31

4.0 709.5+/- LEAN CLAY (CL), with gravel in the upper portion, pale brown to light gray to light brownish-gray to yellow, hard, blocky, marly 5 4.5 tsf (HP) 14

4.5 tsf (HP) 15 37-20-17 73

12-19-21 13 N=40 10

13-20-30 N=50 15.0 698.5+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-9 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 BORING LOG NO. B-6 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Building 2 STRENGTH TEST LIMITS

Latitude: 30.393905° Longitude: -97.652022° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 710 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), trace gravel, dark brown, very stiff 2.5 tsf (HP) 26

3.0 707+/- 3.0 tsf (HP) UC 2.31 15 21 100 LEAN CLAY (CL), grayish-brown in the upper 1-foot, pale brown to light gray to light brownish-gray to yellow below about 1-foot, very stiff to hard, blocky, marly

5 3.5 tsf (HP) 16 35-17-18

4.5 tsf (HP)

4.5 tsf (HP) 15 116

10

13-24-27 N=51 15.0 695+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-10 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 BORING LOG NO. B-7 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Building 7 STRENGTH TEST LIMITS

Latitude: 30.393749° Longitude: -97.65144° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 711.5 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), trace gravel, dark brown, stiff to very stiff 1.5 tsf (HP) 33

3.0 tsf (HP) UC 1.26 7.3 31 88 75-24-51

4.0 707.5+/- LEAN CLAY (CL), grayish-brown in the upper 2 feet, pale brown to light gray to light brownish-gray to yellow below about 2 feet, hard, blocky, marly 5 4.5 tsf (HP) 16

4.5 tsf (HP) 21 101

4.5 tsf (HP) 14 31-19-12

10

15-33-31 N=64 15.0 696.5+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-11 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 BORING LOG NO. B-8 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Building 10 STRENGTH TEST LIMITS

Latitude: 30.393486° Longitude: -97.650751° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 716 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), dark brown, hard

4.5 tsf (HP) 24

2.5 713.5+/- LEAN CLAY (CL), pale brown to light gray to light brownish-gray to yellow, very 4.5 tsf (HP) 15 stiff to hard, blocky, marly

5 4.5 tsf (HP) UC 3.25 4.6 15 111 34-20-14

4.5 tsf (HP) 14

4.5 tsf (HP) 0.4 15 108

10

23-33-46 N=79 15.0 701+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-12 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 BORING LOG NO. B-9 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Building 4 STRENGTH TEST LIMITS

Latitude: 30.393214° Longitude: -97.652494° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 708 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), dark brown, very stiff to hard 2.0 tsf (HP) 32

3.0 tsf (HP) UC 2.96 13.5 25 100

grayish-brown below about 4 feet

5.0 703+/- 4.5 tsf (HP) 20 LEAN CLAY (CL), pale brown to light 5 gray to light brownish-gray to yellow, hard, blocky, marly

4.5 tsf (HP) 18 110

4.5 tsf (HP) 16 38-18-20

10

4.5 tsf (HP)

15.0 693+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-13 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 BORING LOG NO. B-10 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Building 7 STRENGTH TEST LIMITS

Latitude: 30.393378° Longitude: -97.651463° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 710.5 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), trace gravel, dark brown, stiff to very stiff 1.5 tsf (HP) 34

1.0 tsf (HP) 30 88

grayish-brown below about 4 feet

5.0 705.5+/- 2.5 tsf (HP) 17 LEAN CLAY (CL), pale brown to light 5 gray to light brownish-gray to dark yellowish-brown, very stiff to hard, blocky, marly

4.0 tsf (HP) 16 38-18-20

with ferrous partings below about 8 feet

4.0 tsf (HP) 19 106

10

4.5 tsf (HP)

15.0 695.5+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-14 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 BORING LOG NO. B-11 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Building 11 STRENGTH TEST LIMITS

Latitude: 30.393084° Longitude: -97.651049° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 713 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), dark brown, very stiff to hard 4.5 tsf (HP) 19

4.5 tsf (HP) UC 4.24 5.9 22 102 71-22-49 94

5 4.5 tsf (HP) 16 5.5 707.5+/- LEAN CLAY (CL), pale brown to light gray to light brownish-gray to yellow, hard, blocky, marly, with ferrous partings

22-26-36 14 34-17-17 N=62

4.5 tsf (HP) 16 116

10

4.5 tsf (HP)

15.0 698+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-15 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 BORING LOG NO. B-12 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Building 6 STRENGTH TEST LIMITS

Latitude: 30.392954° Longitude: -97.651992° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 707 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), trace gravel, dark brown, very stiff 3.0 tsf (HP) 25

2.5 tsf (HP) 26 97

5 2.5 tsf (HP) 24 69-20-49 90

6.0 701+/- LEAN CLAY (CL), pale brown to light gray to light brownish-gray to yellow, hard, blocky, marly 4.5 tsf (HP) 0.0 14 117

4.5 tsf (HP) 14 33-17-16

10

4.5 tsf (HP)

15.0 692+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-16 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 BORING LOG NO. B-13 Page 1 of 1 PROJECT: Oertli Multifamily CLIENT: CIP Construction Greensboro, North Carolina SITE: E. Parmer Lane, NW of Dessau Rd. Austin, Texas ATTERBERG LOCATION Building 12 STRENGTH TEST LIMITS

Latitude: 30.392649° Longitude: -97.651336° LL-PL-PI WATER (tsf) RESULTS DRY UNIT SWELL (%) DEPTH (Ft.)

Approximate Surface Elev: 710.5 (Ft.) +/- FIELD TEST WEIGHT (pcf) GRAPHIC LOG CONTENT (%) WATER LEVEL TEST TYPE STRENGTH STRAIN (%) SAMPLE TYPE OBSERVATIONS PERCENT FINES

DEPTH ELEVATION (Ft.) COMPRESSIVE FAT CLAY (CH), trace gravel, dark brown, stiff to hard 2.0 tsf (HP) 30

1.5 tsf (HP) UC 4.21 4.8 21 102

5 4.5 tsf (HP) 20 68-22-46 93

6.0 704.5+/- LEAN CLAY (CL), pale brown to light gray to light brownish-gray to yellow, hard, blocky, marly 4.5 tsf (HP) 11

13-21-29 14 N=50 10

16-30-38 N=68 15.0 695.5+/- Boring Terminated at 15 Feet 15

Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic

Advancement Method: See Exhibit A-4 for description of field Notes: Dry Augered 0 to 15 feet procedures See Appendix B for description of laboratory procedures and additional data (if any). Abandonment Method: See Appendix C for explanation of symbols and Borings backfilled with soil cuttings upon completion. abbreviations. Elevations approximated from site topography survey provided to us. WATER LEVEL OBSERVATIONS Boring Started: 10/23/2014 Boring Completed: 10/23/2014 No free water observed Drill Rig: CME 55 Driller: Austin Geo-Logic 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas Project No.: 96145207 Exhibit: A-17 THIS BORING LOG IS NOT VALID SEPARATED IF BORING FROM ORIGINAL REPORT. LOGS.GPJ OERTLI MULTIFAMILY WELL GEO SMART LOG-NO 96145207 APPENDIX B LABORATORY TESTING Geotechnical Engineering Report Oertli Multifamily ■ Austin, Texas November 21, 2014 ■ Terracon Project No. 96145207

Laboratory Testing

Samples obtained during the field program were visually classified in the laboratory by a geotechnical engineer. A testing program was conducted on selected samples, as directed by the geotechnical engineer, to aid in classification and evaluation of engineering properties required for analyses.

Results of the laboratory tests are presented on the boring logs located in Appendix A and/or are discussed in Section 3.0 – Subsurface Conditions of the report. Laboratory test results were used to classify the soils encountered as generally outlined by the Unified Soil Classification System.

Samples not tested in the laboratory will be stored for a period of 30 days subsequent to submittal of this report and will be discarded after this period, unless we are notified otherwise.

Exhibit B-1 GRAIN SIZE DISTRIBUTION ASTM D422 U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS HYDROMETER 4 2 1 1/2 3 6 10 16 30 50 100 200 6 3 1.5 3/4 3/8 4 8 14 20 40 60 140 100

95

90

85

80

75

70

65

60

55

50

45

40

PERCENT FINER BY WEIGHT BY FINER PERCENT 35

30

25

20

15

10

5

0 100 10 1 0.1 0.01 0.001 GRAIN SIZE IN MILLIMETERS GRAVEL SAND COBBLES SILT OR CLAY coarse fine coarse medium fine

Boring ID Depth USCS Classification LL PL PI Cc Cu B-3 4.0 LEAN CLAY(CL) 31 18 13 B-5 6.0 LEAN CLAY with GRAVEL(CL) 37 20 17 B-11 2.0 FAT CLAY(CH) 71 22 49 B-12 4.0 FAT CLAY(CH) 69 20 49 B-13 4.0 FAT CLAY(CH) 68 22 46

Boring ID Depth D100 D60 D30 D10 %Gravel %Sand %Silt %Clay B-3 4.0 9.5 0.004 0.001 6.1 6.8 24.2 62.9 B-5 6.0 25 0.008 0.002 14.1 12.7 21.6 51.6 B-11 2.0 9.5 0.2 6.2 93.5 B-12 4.0 9.5 0.1 9.8 90.1 B-13 4.0 4.75 0.0 6.7 93.3 PROJECT: Oertli Multifamily PROJECT NUMBER: 96145207

SITE: E. Parmer Lane, NW of Dessau Rd. CLIENT: CIP Construction Austin, Texas Greensboro, North Carolina 5307 Industrial Oaks Blvd., Suite 160 Austin, Texas EXHIBIT: B-2 LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. BORING GRAIN SIZE:LOGS.GPJOERTLI MULTIFAMILY TERRACON2012.GDT USCS-2 96145207 11/20/14 APPENDIX C SUPPORTING DOCUMENTS GENERAL NOTES DESCRIPTION OF SYMBOLS AND ABBREVIATIONS

Water Initially N Standard Penetration Test Encountered Resistance (Blows/Ft.) Water Level After a Standard (HP) Hand Penetrometer Shelby Specified Period of Time Penetration Tube Test Water Level After a Specified Period of Time (T) Torvane

Water levels indicated on the soil boring (DCP) Dynamic Cone Penetrometer logs are the levels measured in the borehole at the times indicated. SAMPLING (PID) Photo-Ionization Detector

Groundwater level variations will occur FIELD TESTS WATER LEVEL over time. In low permeability soils, accurate determination of groundwater (OVA) Organic Vapor Analyzer levels is not possible with short term water level observations.

DESCRIPTIVE SOIL CLASSIFICATION Soil classification is based on the Unified Soil Classification System. Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic, and silts if they are slightly plastic or non-plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse-grained soils are defined on the basis of their in-place relative density and fine-grained soils on the basis of their consistency.

LOCATION AND ELEVATION NOTES Unless otherwise noted, Latitude and Longitude are approximately determined using a hand-held GPS device. The accuracy of such devices is variable. Surface elevation data annotated with +/- indicates that no actual topographical survey was conducted to confirm the surface elevation. Instead, the surface elevation was approximately determined from topographic maps of the area.

RELATIVE DENSITY OF COARSE-GRAINED SOILS CONSISTENCY OF FINE-GRAINED SOILS (50% or more passing the No. 200 sieve.) (More than 50% retained on No. 200 sieve.) Consistency determined by laboratory shear strength testing, field Density determined by Standard Penetration Resistance visual-manual procedures or standard penetration resistance

Descriptive Term Standard Penetration or Descriptive Term Unconfined Compressive Strength Standard Penetration or (Density) N-Value (Consistency) Qu, (tsf) N-Value Blows/Ft. Blows/Ft.

Very Loose 0 - 3 Very Soft less than 0.25 0 - 1

Loose 4 - 9 Soft 0.25 to 0.50 2 - 4

Medium Dense 10 - 29 Medium Stiff 0.50 to 1.00 4 - 8

STRENGTH TERMS Dense 30 - 50 Stiff 1.00 to 2.00 8 - 15

Very Dense > 50 Very Stiff 2.00 to 4.00 15 - 30

Hard > 4.00 > 30

RELATIVE PROPORTIONS OF SAND AND GRAVEL GRAIN SIZE TERMINOLOGY

Descriptive Term(s) Percent of Major Component Particle Size of other constituents Dry Weight of Sample Trace < 15 Boulders Over 12 in. (300 mm) With 15 - 29 Cobbles 12 in. to 3 in. (300mm to 75mm) Modifier > 30 Gravel 3 in. to #4 sieve (75mm to 4.75 mm) Sand #4 to #200 sieve (4.75mm to 0.075mm Silt or Clay Passing #200 sieve (0.075mm) RELATIVE PROPORTIONS OF FINES PLASTICITY DESCRIPTION Descriptive Term(s) Percent of Term Plasticity Index of other constituents Dry Weight Non-plastic 0 Trace < 5 Low 1 - 10 With 5 - 12 Medium 11 - 30 Modifier > 12 High > 30

Exhibit: C-1 UNIFIED SOIL CLASSIFICATION SYSTEM Soil Classification A Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests Group Group Name B Symbol E F Gravels: Clean Gravels: Cu t 4 and 1 d Cc d 3 GW Well-graded gravel C E F More than 50% of Less than 5% fines Cu 4 and/or 1 ! Cc ! 3 GP Poorly graded gravel F,G,H coarse fraction retained Gravels with Fines: Fines classify as ML or MH GM Silty gravel C Coarse Grained Soils: on No. 4 sieve More than 12% fines Fines classify as CL or CH GC Clayey gravel F,G,H More than 50% retained E I on No. 200 sieve Sands: Clean Sands: Cu t 6 and 1 d Cc d 3 SW Well-graded sand D E I 50% or more of coarse Less than 5% fines Cu 6 and/or 1 ! Cc ! 3 SP Poorly graded sand G,H,I fraction passes No. 4 Sands with Fines: Fines classify as ML or MH SM Silty sand D sieve More than 12% fines Fines classify as CL or CH SC Clayey sand G,H,I PI ! 7 and plots on or above “A” line J CL Lean clay K,L,M Inorganic: J K,L,M Silts and Clays: PI 4 or plots below “A” line ML Silt Liquid limit less than 50 Liquid limit - oven dried Organic clay K,L,M,N Fine-Grained Soils: Organic: 0.75 OL K,L,M,O Liquid limit - not dried Organic silt 50% or more passes the K,L,M No. 200 sieve PI plots on or above “A” line CH Fat clay Inorganic: K,L,M Silts and Clays: PI plots below “A” line MH Elastic Silt Liquid limit 50 or more Liquid limit - oven dried Organic clay K,L,M,P Organic: 0.75 OH Liquid limit - not dried Organic silt K,L,M,Q Highly organic soils: Primarily organic matter, dark in color, and organic odor PT Peat

A Based on the material passing the 3-inch (75-mm) sieve H If fines are organic, add “with organic fines” to group name. B If field sample contained cobbles or boulders, or both, add “with cobbles I If soil contains t 15% gravel, add “with gravel” to group name. and/or boulders” (or both) to group name. J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. C Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,” gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly whichever is predominant. graded gravel with silt, GP-GC poorly graded gravel with clay. L If soil contains t 30% plus No. 200 predominantly sand, add “sandy” to D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded group name. sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded M If soil contains t 30% plus No. 200, predominantly gravel, add sand with silt, SP-SC poorly graded sand with clay “gravelly” to group name. 2 N (D ) PI t 4 and plots on or above “A” line. E 30 O Cu = D60/D10 Cc = PI 4 or plots below “A” line. P PI plots on or above “A” line. D10 x D60 Q F PI plots below “A” line. If soil contains t 15% sand, add “with sand” to group name.

G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM.

Exhibit C-2