Memorandum. FOUNDATION ENGINEERING, INC. Professional Geotechnical Services. Date: August 13, 2012 To:

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1 FOUNDATION ENGINEERING, INC. Professional Geotechnical Services Memorandum Date: August 13, 2012 To: From: Subject: Project: Brett C. Martin, P.E. LEI Engineering & Surveying, LLC James K. Maitland, P.E., G.E. Matthew D. Mason Geotechnical Investigation Miller Property Subdivision FEI Project We have completed the requested geotechnical investigation for the above-referenced project. The following summarizes our work and provides recommendations for site preparation and foundation design. BACKGROUND The Confederated Tribes of Siletz Indians of Oregon is planning a housing project in. The site is located in a field west of Siletz Hwy between W Buford Avenue and SW Swan Avenue (Figure 1A, Appendix A). The development will consist of 21 lots and associated paved access. The new structures will have framed-floors and shallow foundations. The site layout with the proposed lots and roadway is shown on Figure 2A (Appendix A). LEI Engineering & Surveying, LLC (LEI) is the civil consultant. Foundation Engineering, Inc. (FEI) was retained by LEI as the geotechnical consultant. Our scope of work was outlined in a proposal dated January 4, 2012, and authorized by a signed service agreement dated July 16, FIELD EXPLORATION We dug 12 exploratory test pits at the site on July 20, 2012, using a Kubota KX121-3, rubber-tracked excavator. The approximate test pit locations are shown on Figure 2A. Upon completion of our explorations, the test pits were backfilled with the excavated materials. The test pits extended to depths ranging from ±3 to 9 feet. Disturbed soil samples were obtained for possible laboratory testing. Undrained shear strength measurements were made on the test pit sidewalls using a Torvane shear device. The soil profile, sampling depths and strength measurements are summarized on the test pit logs (Appendix B). Ground elevations shown on the logs were estimated based on the topographic map and are approximate only. The subsurface conditions are discussed below. 820 NW Cornell Avenue Corvallis, Oregon Bus. (541) Fax (541)

2 DISCUSSION OF SITE CONDITIONS Topography and Vegetation The site is relatively flat. Topographic information provided by LEI indicates the ground elevations range from ±El. 97 at the west end of the site to ±El. 102 near the east side of the site. The vegetation within the parcel varies with location. The northwest portion of the site is primarily covered with fir trees. A ditch line vegetated with tall grass, weeds and brambles starts in the middle of the site and continues into the southwest corner of the site. A small mound of fill, located at the west side of the site, is covered with tall grass, weeds and small trees. The remaining portion of the site is primarily covered with mowed grass. Subsurface Conditions Relatively similar conditions were encountered in the test pits. profile typically includes the following soil and rock units: The subsurface Topsoil. Topsoil was encountered to ±1¾ to 3 feet. The topsoil consists of medium to high plasticity silt with some clay and organics consisting of fine roots. The roots typically extended to ±10 to 12 inches below the ground surface. The topsoil was typically damp to moist and medium stiff at the time of the field work. Clayey Silt (alluvium). The topsoil is underlain by medium to high plasticity clayey silt. The clayey silt has a blocky structure and was typically moist and stiff at the time of the exploration. This stratum extends to ±5½ to 7½ feet. Sandy SILT/silty SAND (alluvium). Brown to grey, iron-stained, medium dense to medium stiff, low to medium plasticity silty sand to sandy silt was encountered beneath the clayey silt layer within the western and southern portions of the site (TP-1 through TP-3, TP-8 and TP-12). This stratum was ±1 to 2 feet thick in TP-1, TP-3 and TP-12 and at least ±2 feet thick in TP-2 and TP-8, where it extended to the bottom of the test pits. Gravel (alluvium). Dense, fine to coarse, subrounded to rounded sandy gravel was encountered in TP-3 through TP-5, TP-9, TP-11 and TP-12. Scattered cobbles were present in the gravel in TP-4, TP-5 and TP-9. The sandy gravel was encountered beneath the clayey silt and silty sand and typically extended to the limits of the exploration (±8 to 8½ feet below the ground surface). Siltstone. Extremely weak (R0) siltstone of the Tyee Formation was encountered at a depth of ±8 feet in TP-3. Digging extended ±½-foot into the bedrock. The exposed rock surface is typically slightly to moderately weathered. Excavation below the rock surface was difficult with the Kubota KX121-3 excavator. Miller Property Subdivision August 13, 2012 Geotechnical Investigation 2. Project LEI Engineering & Surveying, LLC

3 Ground Water We observed slow ground water infiltration in several of the test pits at a depth of ±8 feet. Where ground water was observed, the depth corresponds to approximately the contact between the fine-grained and coarse-grained soils. The shallower soils were typically damp to moist at the time of the exploration. However, the observed iron-staining in the upper fine-grained soils suggests perched water conditions may develop during periods of extended rainfall and ground water levels may rise to within the ground surface during the wet winter months. Neighbors indicated standing water is often observed across the site during periods of heavy rainfall, which suggests poor infiltration characteristics of the surficial soils. Infiltration It is our understanding the project will include permeable pavements as part of the drainage design for the site. LEI requested FEI to comment on the permeability of the near-surface soils and the feasibility of the drainage plan. The site is typically underlain by ±5½ to 7½ feet of fine-grained soil over sand and gravel. The fine-grained topsoil consists of ±2 to 3 feet of medium to high plasticity silt (MH) over medium to high plasticity, alluvial clayey silt (MH). These types of soils typically have a coefficient of hydraulic conductivity (permeability), k, ranging from ±10-5 to 10-7 cm/sec. Soils with k values of less than ±10-5 cm/sec are generally considered to have very low permeability. Soils with k values less than ±10-7 cm/sec are considered to be practically impermeable. Additionally, the site s proximity to the Siletz River suggests the ground water level beneath the site will closely match the river level. During periods of extended heavy rainfall, the ground water level will likely rise to reflect rising river levels. As a result of these conditions, the subgrade beneath the proposed permeable pavements should be considered relatively impermeable and will provide little storage capacity for runoff. This is consistent with the neighbor s observations of ponding water on the site. LABORATORY TESTING Laboratory testing was limited to natural water content, percent fines and Atterberg limits tests on a sample of the foundation soil. The testing was completed to classify the soil according to the Unified Soil Classification System (USCS) and estimate its overall engineering properties. The testing indicates the foundation soils consist predominantly of medium plasticity clayey silt and silt with some clay. The test results are summarized in Table 1 and Figure 3A (Appendix A). Miller Property Subdivision August 13, 2012 Geotechnical Investigation 3. Project LEI Engineering & Surveying, LLC

4 Table 1. Atterberg Limits, Natural Water Contents, and Percent Fines Sample Number Sample Depth (feet) Moisture Content (percent) LL PL PI USCS Classification Percent Fines S S S MH S S S MH S S S S SEISMIC CONSIDERATIONS Response Spectrum A spectral acceleration response spectrum for the site was established based on Section 1613 of the Oregon Structural Specialty Code (OSSC) Based on our explorations, we anticipate the site is underlain by ±10 to 15 feet of medium stiff to stiff clayey silt, medium dense silty sand and sandy silt, and dense gravel followed by siltstone (extending to great depth). Therefore, a Site Class C is recommended for design, based on the average profile within 100 feet of the ground surface. The seismic design parameters and OSSC response spectrum are shown on Figure 4A (Appendix A). Liquefaction Liquefiable soils typically consist of saturated, loose, fine-grained sand and non-plastic silt. The liquefaction potential of the foundation soils is considered negligible due to the plasticity and stiffness of the fine-grained soils, limited thickness, density and plasticity of the silty sand and sandy silt, and the presence of shallow bedrock. Miller Property Subdivision August 13, 2012 Geotechnical Investigation 4. Project LEI Engineering & Surveying, LLC

5 ENGINEERING ANALYSIS AND DESIGN Bearing Capacity We estimated the bearing capacity of conventional (i.e., spread or continuous) footings placed on ±6 inches of compacted Select Fill underlain by silt with some clay or clayey silt. Torvane shear measurements near the anticipated foundation elevation indicated undrained shear strengths ranging from ±0.5 to 0.85 tsf. An allowable bearing capacity was calculated using conservative undrained shear strength of 0.4 tsf. These calculations suggest an allowable bearing pressure of 2,000 psf with a typical factor of safety of 3. This analysis assumes the continuous footings will have a nominal width of 18 inches and the subgrade beneath the footings would be prepared as recommended below. Settlement A conventional settlement analysis was not warranted based on the stiffness of the foundation soils and the light building loads. We recommend designing the structures to accommodate a total foundation settlement of ±½ inch. Differential settlement is also expected to be less than ±½ inch. Due to the plasticity of the subgrade, it is possible that seasonal changes in moisture could cause heave (due to wetting) or shrinkage settlement (due to drying). Therefore, provisions to reduce the potential adverse impact of differential soil movement are provided in the Recommendations section. Pavement Analysis and Design It is our understanding a pavement section for the approach aprons will be 3 inches of asphaltic concrete (AC) over 12 inches of Select Fill. The pavement section for the private street (inside the property line) will consist of a 2¾-inch thick paver block underlain by 2 inches of coarse sand and 10 inches of Select Fill over a Separation Geotextile. We conducted a pavement analysis to confirm the suitability of the proposed approach pavement section. We did not evaluate the paver pavement section. We used a computer program, assumed traffic, a subgrade modulus (Mr) of ±3,100 psi and a 20-year design life to estimate a pavement section for the new road. The assumed traffic was based on a traffic distribution of passenger vehicles and pickup trucks and light truck traffic. The subgrade modulus was determined from Dynamic Cone Penetrometer (DCP) testing completed during the field exploration. We understand only some of the housing units will be built during the initial development of the site. The rest of the housing units will be built as more funding becomes available. LEI indicated the area to be developed later is located in the northern portion where the residential road connects with W Buford Avenue. The road in this area will not be paved until after the entire site is developed. However, it should be assumed that with only 12 inches of base aggregate over a Separation Geotextile, future construction traffic will likely cause the subgrade beneath the base aggregate section to pump. Therefore, any areas where the Miller Property Subdivision August 13, 2012 Geotechnical Investigation 5. Project LEI Engineering & Surveying, LLC

6 subgrade is damaged by construction traffic should be reworked prior to paving. We recommend a FEI representative be on site to observe a proof roll of the unpaved road prior to paving. RECOMMENDATIONS The site is underlain by fine-grained alluvium. This soil will be moisture-sensitive and will soften considerably when wet. Compaction of these soils and reuse of the soil as fill will only be practical in the dry summer months when moisture-conditioning is possible. Construction during the winter will require removal of soft soils and construction of thick building pads and thick base rock sections for pavement areas to support construction traffic. Construction during wet weather will substantially increase earthwork costs relative to dry weather construction. Therefore, we recommend completing the earthwork during the dry summer months. The site is relatively flat and has poor drainage. Consequently, the surficial soils may remain wet of optimum into June. Favorable conditions for moisture-conditioning and compaction (i.e., adequately dry soils and sustained dry weather) are typically limited to July through September. The recommendations provided below assume dry weather construction and a subgrade sufficiently dry for compaction. We should be contacted to modify our recommendations if wet weather conditions are anticipated. We have also assumed, based on proposed finish grades, no significant site fill will be required. Contractors should be provided a copy of this memorandum to review recommendations for site preparation and foundation construction, and the soil and rock conditions encountered in the test pits. We should be provided an opportunity to meet with the contractor prior to construction to discuss the site conditions and the contractor s approach to site preparation. Material and Compaction Recommendations 1. Select Fill as defined in this report should consist of 1 or ¾-inch minus, clean (i.e., less than 5% passing the #200 U.S. Sieve), well-graded crushed gravel or rock. A gradation curve should be provided to us for approval, prior to delivery to the site. 2. On-Site Fill should consist of approved soil that is free of organics, construction debris or expansive clay. Unless approved by us, silts or clays should not be placed under foundation areas or under settlement-sensitive structures. Re-use of fine-grained site fill should be limited to general grading and parking lot construction. 3. Drain Rock should consist of 2-inch minus, clean (less than 2% passing the #200 sieve), open-graded gravel or rock. Miller Property Subdivision August 13, 2012 Geotechnical Investigation 6. Project LEI Engineering & Surveying, LLC

7 4. Separation Geotextile shall have Mean Average Roll Value (MARV) strength properties meeting the requirements of an AASHTO M Class 2 geotextile (geotextile for separation). The geotextile should have MARV permittivity of 0.2 to 0.5 sec. -1 and a maximum Apparent Opening Size (AOS) of 0.6 mm. We should be provided a specification sheet on the selected geotextile for approval prior to delivery to the site. 5. Filter Fabric should have Mean Average Roll Value (MARV) strength properties meeting the requirements of an AASHTO M Class 3 geotextile (subsurface drainage geotextile) with a maximum apparent opening size (AOS) of 0.3 mm and a permittivity greater than 0.1 sec Compact the subgrade (during dry weather only) and fill to 95% relative compaction. The maximum dry density of ASTM D 698 should be used as the standard for estimating the relative compaction. The moisture content of the fine-grained soil should be adjusted to within ±2% of its optimum value prior to compaction. Place and compact all fill in loose lifts not exceeding 12 inches. Thinner (±6 to 8 inch) lifts may be required if light or hand-operated equipment is used. Field density tests should be run frequently to confirm adequate compaction of the subgrade and imported fills. Granular fill that contains aggregates too coarse for density testing, or subgrade that is too variable should be proof-rolled using a loaded, 10-yd 3 dump truck or other approved vehicle. The adequacy of the compaction should be evaluated by an FEI representative. Areas of pumping or deflection observed beneath the truck wheels may be reworked, or overexcavated and replaced with compacted Select Fill and proof-rolled again. 7. Overexcavate all test pits that extend under buildings and pavements. Replace the test pit backfill with compacted Select Fill. The test pit locations identified on Figure 2A should be considered approximate only. The test pit locations were staked in the field at the time of the exploration. 8. Excavate for utilities to the required grade. Inform contractors that water infiltration may be encountered at shallow depths during the winter months, based on the observed iron-staining in the upper soils in the test pits. Trenches should be pumped dry prior to placing the backfill. Trench backfill that extends beneath the new building, pavements and hardscapes should consist of Select Fill placed and compacted as specified above. Sidewalls of trenches extending to sands and gravels can collapse suddenly, especially in the presence of seepage. Therefore, all excavations should be shored to protect workers from sloughing or caving soils according Oregon OSHA requirements for Type C soils. Miller Property Subdivision August 13, 2012 Geotechnical Investigation 7. Project LEI Engineering & Surveying, LLC

8 Site Preparation for Buildings We recommend the foundation area under the building be prepared during dry weather as follows: 9. Strip the existing ground ±4 to 6 inches or as required to remove roots and sod. Deeper stripping will be required where tree roots are encountered. Dispose of all strippings outside of construction areas. 10. Moisture-condition, compact and test the subgrade as recommended in Item 6. Compaction will not be practical if the soils are too wet of optimum. Therefore, the site work should not be attempted during wet weather and should be delayed until the subgrade soils are sufficiently dry or until weather permits efficient aeration. 11. Do not allow the subgrade to dry out following preparation. Place a minimum of 12 inches of Select Fill on the prepared subgrade to create a building pad. Place additional Select Fill as needed to raise the top of the building pad at least 12 inches above the finished grade surrounding the buildings to raise the buildings above the seasonal perched water. Compact the Select Fill as recommended in Item Grade the ground surface surrounding all buildings to promote runoff away from the foundations. 13. Provide a minimum of 6 inches of compacted Select Fill under all other isolated concrete slabs and sidewalks (dry weather construction). This rock thickness is not intended to support trucks or heavy equipment and should be increased for wet weather construction. Foundation Design and Construction We understand framed-floor construction has been selected for the project. We recommend the foundations be constructed as follows: 14. Design all continuous wall footings and isolated column footings using an allowable bearing pressure of 2,000 psf. This value assumes all footings or Select Fill underlying the footings will extend to soil having a minimum undrained shear strength of 0.4 tsf. 15. Assume total and differential settlements of ½ inch or less, if the footings are designed and built as specified herein. 16. Design the buildings assuming the seismic parameters and Site Response Spectrum provided in Figure 4A. Values provided in Figure 4A are based on the Oregon Structural Specialty Code (OSSC) 2010 (Section 1613). 17. The framed-floor should be supported on continuous reinforced interior and exterior wall footings. Miller Property Subdivision August 13, 2012 Geotechnical Investigation 8. Project LEI Engineering & Surveying, LLC

9 18. Provide a minimum footing width of 18 inches for continuous wall footings. Place the base of all footings at least 18 inches below the adjacent finished grade. 19. Trench for footings using a hoe equipped with a smooth bucket to reduce subgrade disturbance. The excavations should be deep enough to accommodate a minimum of 6 inches of compacted Select Fill beneath the footings. Excavations should terminate in silt having a minimum undrained shear strength of 0.4 tsf. All footing excavations should be evaluated by an FEI representative prior to backfilling. 20. Overexcavate any unsuitable fill or debris encountered beneath footings. Backfill the overexcavated areas using compacted Select Fill. If needed, dewater the excavations prior to placing backfill. All footing excavations should be evaluated by an FEI representative prior to backfilling. 21. Provide a suitable vapor barrier on the surface of the crawl space. 22. Garage slabs and any concrete driveways should be reinforced to reduce cracking and warping. Rebar, instead of wire mesh, is recommended due to potential seasonal soil movement. The use of fiber as the sole method of reinforcement is not recommended. Drainage for Buildings 23. Install foundation drains along the perimeter of the buildings. The drains should consist of 3 or 4-inch diameter, perforated or slotted, PVC pipe. The flowline of the pipe should be set at the footing grade. The pipe should be bedded in at least 4 inches of Drain Rock and backfilled to within 6 inches of the ground surface with Drain Rock. The entire mass of Drain Rock should be wrapped in a Filter Fabric that laps at least 12 inches at the top. 24. Provide clean-outs at appropriate locations for future maintenance of the drainage systems. 25. Discharge by gravity flow into the nearest storm drain. If necessary, discharge the water into a common sump and pump it into the nearest storm drain. Subgrade Preparation for Pavements 26. Strip the existing ground ±4 to 6 inches or as required to remove sod and roots. Additional excavation may be required where tree roots or unsuitable soils are present. Dispose of all strippings outside of construction areas. 27. Moisture-condition and compact the subgrade and any On-Site Fill as recommended in Item 6. Miller Property Subdivision August 13, 2012 Geotechnical Investigation 9. Project LEI Engineering & Surveying, LLC

10 28. Do not allow the subgrade to dry out excessively. Immediately cover the prepared subgrade with a Separation Geotextile. 29. The geotextile should be laid smooth, without wrinkles or folds in the direction of construction traffic. Overlap adjacent rolls a minimum of 2 feet. Pin fabric overlaps or place the building pad fill in a manner that will not separate the overlap during construction. Seams that have separated will require removal of the building pad fill to establish the required over lap. 30. Assume the subgrade will have relatively low permeability. DESIGN REVIEW/CONSTRUCTION OBSERVATION/TESTING We should be provided the opportunity to review all drawings and specifications that pertain to site preparation and foundation construction. Site preparation will require field confirmation of the foundation conditions and proper subgrade preparation, in particular, if the soils are wet of optimum. Therefore, we recommend we be present during site grading, foundation construction, and subgrade preparation for pavements. Mitigation of any subgrade pumping or presence of persistent ground water will also require engineering review and judgment. That judgment should be provided by one of our representatives. Field density tests should be run on all engineered fill. We recommend we be retained to provide the necessary construction observations. VARIATION OF SUBSURFACE CONDITIONS, USE OF THIS REPORT AND WARRANTY The analysis, conclusions and recommendations contained herein are based on the assumption that the soil profiles encountered in the test pits and the ground water levels are representative of the overall site conditions. The above recommendations assume we will have the opportunity to review final drawings and be present during site grading and foundation construction to confirm the assumed foundation conditions and the plasticity of the exposed soils. No changes in the enclosed recommendations should be made without our approval. We will assume no responsibility or liability for any engineering judgment, inspection or testing performed by others. This memorandum was prepared for the exclusive use of LEI Engineering & Surveying, LLC and their design consultants for the Miller Property Subdivision project in. Information contained herein should not be used for other sites or for unanticipated construction without our written consent. This memorandum is intended for planning and design purposes. Contractors using this information to estimate construction quantities or costs do so at their own risk. Our services do not include any survey or assessment of potential surface contamination or contamination of the soil or ground water by hazardous or toxic materials. We assume that those services, if needed, have been completed by others. Miller Property Subdivision August 13, 2012 Geotechnical Investigation 10. Project LEI Engineering & Surveying, LLC

11 Climate conditions in western Oregon typically consist of wet weather for almost half of the year (typically between mid-october and late May). The recommendations for site preparation and foundation drainage are not intended to represent any warranty (expressed or implied) against the growth of mold, mildew or other organisms that grow in a humid or moist environment. Our work was done in accordance with generally accepted soil and foundation engineering practices. No other warranty, expressed or implied, is made. It has been a pleasure assisting you with this phase of your project. Please let us know if you have any questions or need further assistance. Miller Property Subdivision August 13, 2012 Geotechnical Investigation 11. Project LEI Engineering & Surveying, LLC

12 Appendix A Figures Professional Geotechnical Services Foundation Engineering, Inc.

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16 Spectral Acceleration, S a (g) OSSC 2010 Response Spectrum Period (seconds) Notes: 1. The Design Response Spectrum is based on OSSC 2010 Section 1613 using the following parameters: Site Class= C Damping = 5% S S = 1.43 F a = 1.00 S MS = 1.43 S DS = 0.95 S 1 = 0.66 F v = 1.30 S M1 = 0.86 S D1 = S S and S 1 values for 5% damping are based on the USGS 2002 mapped maximum considered earthquake spectral acclerations for 2% probability of exceedence in 50 years. The corresponding peak ground acceleration on rock is 0.57g. 3. F a and F v were established based on OSSC 2010, Tables (1) and (2) using the selected S S and S 1 values. S DS and S D1 values include a 2/3 reduction on S MS and S M1 as discussed in OSSC 2010 Section Site location is: Latitude , Longitude FIGURE 4A. OSSC 2010 SITE RESPONSE SPECTRUM Miller Property Subdivision FEI Project

17 Appendix B Test Pit Logs Professional Geotechnical Services Foundation Engineering, Inc.

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21 Comments Depth, Feet Sample # Location Class Symbol Water Table C, TSF Symbol Soil and Rock Description Surface: grass. Roots extend to ±12 inches. 1 Medium stiff SILT, some clay and organics; dark brown, damp, medium to high plasticity, organics consist of fine roots, (topsoil). 2 3 S Stiff clayey SILT; brown, moist, medium to high plasticity, blocky structure, (alluvium). 4 5 S-1-2 Becomes grey and iron-stained with trace gravel below ±5 feet. 6 7 S-1-3 Medium stiff sandy SILT, trace gravel; light grey, iron-stained, moist to wet, medium plasticity, fine sand, (alluvium). No seepage or ground water encountered to the limit of excavation. 8 9 S-1-4 Very weak (R1) SILTSTONE; grey, moderately to slightly weathered, (Tyee Formation). BOTTOM OF TEST PIT 10 Project No.: Surface Elevation: Test Pit Log: TP feet (Approx.) Miller Property Subdivision Date of Test Pit: July 20, 2012 Comments Depth, Feet Sample # Location Class Symbol Water Table C, TSF Symbol Soil and Rock Description Surface: grass. Roots extend to ±10 inches. 1 S-2-1 Medium stiff SILT, some clay and organics; dark brown, damp, medium to high plasticity, organics consist of fine roots, (topsoil). 2 3 S Stiff clayey SILT; brown, moist, medium to high plasticity, blocky structure, (alluvium). Becomes iron-stained below ±3 feet. 4 5 S S-2-4 Medium stiff sandy SILT; brown, iron-stained, moist to wet, low to medium plasticity, fine to medium sand, (alluvium). 7 No seepage or ground water encountered to the limit of excavation. 8 9 BOTTOM OF TEST PIT 10 Project No.: Surface Elevation: Test Pit Log: TP feet (Approx.) Miller Property Subdivision Date of Test Pit: July 20, 2012

22 Comments Depth, Feet Sample # Location Class Symbol Water Table C, TSF Symbol Soil and Rock Description Surface: grass. Roots extend to ±12 inches. 1 S-3-1 Medium stiff SILT, some clay and organics; dark brown, damp, medium to high plasticity, organics consist of fine roots, (topsoil) S Medium stiff SILT, some clay; brown, damp to moist, medium to high plasticity, blocky structure, (alluvium). Becomes moist below ±4 feet Medium dense silty SAND; brown, moist, low to medium plasticty silt, fine to medium sand, (alluvium). Ground water at ±8 feet. 8 9 S-3-3 Medium dense sandy GRAVEL; brown, wet, fine to coarse sand, fine to coarse, subrounded to rounded gravel, (alluvium). BOTTOM OF TEST PIT 10 Project No.: Surface Elevation: Test Pit Log: TP feet (Approx.) Miller Property Subdivision Date of Test Pit: July 20, 2012 Comments Depth, Feet Sample # Location Class Symbol Water Table C, TSF Symbol Soil and Rock Description Surface: grass. Fine roots extend to ±12 inches. 1 2 S-4-1 Medium stiff SILT, some clay and organics; dark brown, moist, medium to high plasticity, organics consist of roots, (topsoil) Stiff clayey SILT; brown, moist, medium to high plasticity, blocky structure, (alluvium). 5 S-4-2 Becomes grey-brown and iron-stained below ±4.5 feet. 6 7 Ground water at ±8 feet. 8 9 Medium dense to dense sandy GRAVEL, scattered cobbles; brown, wet, fine to medium sand, fine to coarse, subrounded to rounded gravel and cobbles, (alluvium). BOTTOM OF TEST PIT 10 Project No.: Surface Elevation: Test Pit Log: TP feet (Approx.) Miller Property Subdivision Date of Test Pit: July 20, 2012

23 Comments Depth, Feet Sample # Location Class Symbol Water Table C, TSF Symbol Soil and Rock Description Surface: grass. Fine roots extend to ±12 inches. 1 S-5-1 Medium stiff SILT, some clay and organics; dark brown, moist, medium to high plasticity, organics consist of fine to medium roots, (topsoil) S Stiff clayey SILT; brown, iron-stained, moist, medium to high plasticity, blocky structure, (alluvium). 5 No seepage or ground water encountered to the limit of excavation Medium dense to dense sandy GRAVEL, scattered cobbles; brown, moist, fine sand, fine to coarse, subrounded to rounded gravel and cobbles, cobbles up to ±5 inches in diameter. BOTTOM OF TEST PIT 9 10 Project No.: Surface Elevation: Test Pit Log: TP feet (Approx.) Miller Property Subdivision Date of Test Pit: July 20, 2012 Comments Depth, Feet Sample # Location Class Symbol Water Table C, TSF Symbol Soil and Rock Description Surface: grass. Fine roots extend to ±12 inches. 1 S-6-1 Medium stiff SILT, some clay and organics; dark brown, moist, medium to high plasticity, organics consist of fine roots, (topsoil). 2 No seepage or ground water encountered to the limit of excavation Medium stiff to stiff clayey SILT; brown, moist, medium to high plasticity, blocky structure, (alluvium). BOTTOM OF TEST PIT Project No.: Surface Elevation: Test Pit Log: TP feet (Approx.) Miller Property Subdivision Date of Test Pit: July 20, 2012

24 Comments Depth, Feet Sample # Location Class Symbol Water Table C, TSF Symbol Soil and Rock Description Surface: grass. Roots extend to ±12 inches. 1 Medium stiff SILT, some clay and organics; dark brown, damp, medium to high plasticity, organics consist of fine roots, (topsoil). No seepage or ground water encountered to the limit of excavation S Medium stiff to stiff clayey SILT; brown, moist, medium to high plasticity, blocky structure, (alluvium). BOTTOM OF TEST PIT Project No.: Surface Elevation: Test Pit Log: TP feet (Approx.) Miller Property Subdivision Date of Test Pit: July 20, 2012 Comments Depth, Feet Sample # Location Class Symbol Water Table C, TSF Symbol Soil and Rock Description Surface: grass. Roots extend to ±12 inches. 1 Medium stiff SILT, some clay and organics; dark brown, damp, medium to high plasticity, organics consist of fine roots, (topsoil). 2 3 S Medium stiff to stiff clayey SILT; brown, iron-stained, moist, medium to high plasticity, blocky structure, (alluvium) Becomes soft and wet at ±6.5 feet. Ground water at ±8 feet. 7 8 Medium dense silty SAND; yellow-brown, wet, low to medium plasticity silt, fine sand, (alluvium) BOTTOM OF TEST PIT Project No.: Surface Elevation: Test Pit Log: TP feet (Approx.) Miller Property Subdivision Date of Test Pit: July 20, 2012

25 Comments Depth, Feet Sample # Location Class Symbol Water Table C, TSF Symbol Soil and Rock Description Surface: grass. Fine roots extend to ±12 inches. 1 Medium stiff SILT, some clay and organics; dark brown, damp to moist, medium to high plasticity, organics consist of fine to medium roots, (topsoil) S Stiff clayey SILT; brown, moist, medium to high plasticity, blocky structure, (alluvium). Becomes iron-stained below ±4 feet. 5 No seepage or ground water encountered to the limit of excavation Medium dense to dense sandy GRAVEL, scattered cobbles; brown, moist, fine sand, fine to coarse, subrounded to rounded gravel and cobbles, (alluvium). BOTTOM OF TEST PIT 9 10 Project No.: Surface Elevation: Test Pit Log: TP feet (Approx.) Miller Property Subdivision Date of Test Pit: July 20, 2012 Comments Depth, Feet Sample # Location Class Symbol Water Table C, TSF Symbol Soil and Rock Description Surface: grass. Fine roots extend to ±12 inches. 1 Medium stiff SILT, some clay and organics; dark brown, moist, medium to high plasticity, organics consist of fine roots, (topsoil). 2 No seepage or ground water encountered to the limit of excavation S Stiff clayey SILT; brown, moist, medium to high plasticity, blocky structure, (alluvium). BOTTOM OF TEST PIT Project No.: Surface Elevation: Test Pit Log: TP feet (Approx.) Miller Property Subdivision Date of Test Pit: July 20, 2012

26 Comments Depth, Feet Sample # Location Class Symbol Water Table C, TSF Symbol Soil and Rock Description Surface: grass. Fine roots extend to ±12 inches. 1 Medium stiff SILT, some clay and organics; dark brown, damp, medium to high plasticity, organics consist of fine to medium roots, (topsoil) S Stiff clayey SILT; brown, damp to moist, medium to high plasticity, blocky structure, (alluvium). 5 S S-11- Dense sandy GRAVEL; brown, moist, fine to medium sand, fine to coarse subrounded to rounded gravel, (alluvium). Scattered cobbles (up to ±12 inches in diameter) below ±6 feet. No seepage or ground water encountered to the limit of excavation. 8 9 BOTTOM OF TEST PIT 10 Project No.: Surface Elevation: Test Pit Log: TP feet (Approx.) Miller Property Subdivision Date of Test Pit: July 20, 2012 Comments Depth, Feet Sample # Location Class Symbol Water Table C, TSF Symbol Soil and Rock Description Surface: grass. Roots extend to ±12 inches. 1 S-12-1 Medium stiff SILT, some clay and organics; dark brown, damp, medium to high plasticity, organics consist of fine roots, (topsoil). 2 3 S Medium stiff to stiff clayey SILT; brown, iron-stained, moist, medium to high plasticity, blocky structure, (alluvium). 4 5 Becomes grey-brown and iron-stained below ±5 feet. 6 Ground water at ±8 feet S-12-3 Medium dense silty SAND; grey-brown, iron and manganese-stained, wet, low to medium plasticity, fine to medium sand, (alluvium). Medium dense sandy GRAVEL; grey-brown, wet, fine to medium sand, fine to coarse, subrounded to rounded gravel, (alluvium). BOTTOM OF TEST PIT Project No.: Surface Elevation: Test Pit Log: TP feet (Approx.) Miller Property Subdivision Date of Test Pit: July 20, 2012