The URL can be used to link to this page

Home My WebLink AboutPermit File BLD-2019-0629 1207 6th Street (2) tihotai Materials Testing & Consulting, Inc. - -- it Geotechnical Engineering•Materials Testing•Special Inspection•Environmental Consulting a,,Al o` jM4tenals Testing&ConsuthnS,n January 10, 2019 Michael Huber, Owner/Developer fii) . . ( F > f; 12814 127th Ave. SE. l 1)' Snohomish, WA 98290 , MAY 31 2019 • SEP 2 7-2019 " t. Mwhuber@mac.com r` (425) 239-7333 CITY OF ANACORTES °- , c;c_'t, Subject: Geotechnical Investigation and Engineering Report Proposed Residential Development 1211 6th Street, r� Anacortes, Washington 98221 L® �� `g - L MTC Project No.: 1813355 I 1/ 6 'f-� f , Dear Mr. Huber: This letter transmits our Geotechnical Engineering Investigation Report for the above-referenced project. Materials Testing & Consulting, Inc. (MTC) performed this geotechnical study in accordance with our Proposal for Geotechnical Services, dated November 7th, 2018. We would be pleased to continue our role as your geotechnical engineering consultants during the project planning and construction. We also have a keen interest in providing materials testing and special inspection during construction of this project. We will be pleased to meet with you at your convenience to discuss these services. We appreciate the opportunity to provide geotechnical services to you for this project. If you have any questions regarding this report, or if we can provide assistance with other aspects of the project, please contact us at(360) 755-1990. Respectfully Submitted, MATERIALS TESTING&CONSULTING,INC. "L- Y.z-Zert )---' ---.- -- John Gillaspy, L.E. Kevin Quillan, G.I.T. NW Region Geotechnical Division Manager Project Geologist Attachment: Geotechnical Investigation and Engineering Report Corporate • 777 Chrysler Drive • Burlington, WA 98233 • Phone 360.755.1990 • Fax 360.755.1980 SW Region • 2118 Black Lake Blvd. S.W.• Olympia, WA 98512 • Phone 360.534.9777 • Fax 360.534.9779 NW Region • 805 Dupont, Suite #5 • Bellingham, WA 98225 • Phone 360.647.6061 • Fax 360.647.8111 Kitsap Region • 5451 N.W. Newberry Hill Road, Suite 101 • Silverdale, WA 98383 • Phone/Fax 360.698.6787 Visit our website: www.mtc-inc.net GEOTECHNICAL INVESTIGATION AND ENGINEERING REPORT PROPOSED SINGLE-FAMILY RESIDENCE AND DETACHED GARAGE 1211 6TH STREET ANACORTES, WASHINGTON 98221 Michael Huber, Owner/Developer 12814 127th Ave. SE. Snohomish, WA 98290 Mwhuber@mac.com (425) 239-7333 Prepared by: ash tR 6 o W i �, �TF, e21 410P) "- ;41r0*.- ‘sc: .1 '/.14. ,,, 114_1 ii,,,,,:,:,-; a p / `. ngineeBn9 -Aegis .�4. A, GG tp 2856 1-10-19 410NA►. 0 1-10-19 John R. Gillaspy John Gillaspy, L.E.G. Medhanie Tecle, P.E. NW Region Geotechnical Division Manager Engineering Manager Additional Work By: Kevin Quillan, G.I.T. Project Geologist ----i' MATERIALS TESTING & CONSULTING, INC. (MTC) 777 Chrysler Drive tl lienal Burlington, Washington 98233 Phone: (360) 755-1990 e0 Fax (360) 755-1980 ii- •.• January 10 2019 ?-arerjals Testing&Consults g o trot MTC Project Number: 18B355 IP Copyright 2018 Materials Testing & Consulting, Inc. All Rights Reserved ii Huber Residence Geotechnical Report Materials Testing & Consulting, Inc. January 10 , 2019 Project No . : 18B355 Table of Contents 1 . 0 INTRODUCTION 1 1 . 1 GENERAL 1 1 .2 PROJECT DESCRIPTION 1 1 . 3 PURPOSE AND SCOPE OF SERVICES 2 2 . 0 SITE EXPLORATION AND LABORATORY TESTING 3 2 . 1 SITE EXPLORATION 3 2 .2 LABORATORY TESTING 3 3 . 0 EXISTING SITE CONDITIONS 4 3 . 1 SURFACE DESCRIPTION 4 3 .2 AREA GEOLOGY 4 3 . 3 SOIL CONDITIONS 5 3 .4 GROUNDWATER CONDITIONS 6 4 . 0 KEY GEOLOGIC CONSIDERATIONS . . 8 4 . 1 GENERAL SITE SOIL CONDITIONS 8 4 .2 SCOPE OF SITE GRADING 8 4 . 3 TEMPORARY EXCAVATION CUT SLOPES , SHORING, AND DEWATERING 9 5 . 0 DESIGN RECOMMENDATIONS 10 5 . 1 FOUNDATION FEASIBILITY 10 5 .2 FOUNDATION RECOMMENDATIONS 11 5 . 3 SLAB -ON-GRADE CONSTRUCTION 13 5 .4 RETAINING WALL DESIGN 15 5 . 5 SEISMIC DESIGN PARAMETERS AND LIQUEFACTION POTENTIAL 17 5 . 6 INFILTRATION RATE DETERMINATION 18 6 . 0 CONSTRUCTION RECOMMENDATIONS 21 6 . 1 EARTHWORK 21 6 . 1 . 1 Excavation 21 6 . 1 .2 Subgrade Evaluation and Preparation 21 6 . 1 . 3 Site Preparation, Erosion Control and Wet Weather Construction 21 6 . 2 STRUCTURAL FILL MATERIALS AND COMPACTION 22 6 .2 . 1 Materials 22 6 .2 .2 Placement and Compaction 23 6 . 3 TEMPORARY EXCAVATIONS AND SLOPES 23 6 .4 PERMANENT SLOPES 24 6 . 5 UTILITY TRENCHES AND EXCAVATIONS 24 7 . 0 ADDITIONAL RECOMMENDED SERVICES 25 8 . 0 LIMITATIONS 26 Appendix A . SITE LOCATION AND VICINITY 27 Appendix B. EXPLORATION LOCATIONS 28 Appendix C. EXPLORATION LOGS 29 Appendix D. LABORATORY RESULTS 38 111 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 1.0 INTRODUCTION 1.1 GENERAL This report presents the findings and recommendations of Materials Testing & Consulting, Inc.'s (MTC) geotechnical engineering study conducted for the design and construction of the proposed single-family residential development with associated detached garage. The subject site is located in the historical neighborhood of Anacortes, Washington along 6th Street. The site location, aerial photo overview, and proposed layout of the project site are presented in Figures 1 and 2 of Appendices A and B. 1.2 PROJECT DESCRIPTION The client intends to construct a large single-family residence and detached two-story garage within the previously developed residential site consisting of approximately 0.24 acres (Figure 2). The main residence will be constructed in the northeastern portion of the site and will consist of a crawl space at the southern end of the building with an underground basement level at the northern end of the structure with a retaining wall foundation. The two-story garage is proposed to be constructed at the southwestern corner of the site. The redevelopment will also require stormwater control improvements to service new impervious area, including on-site infiltration, if feasible. Currently, the client is considering the northwest and southeast corner of the site for construction of onsite infiltration facilities. The site is presently undeveloped and primarily unvegetated following demolition of the previous residence. Topography across the site is generally flat with slight undulations and a minor swale in the northwest corner of the lot. The northern end of the property consists of a 4.5 to 6.5-foot high moderately sloping hillside presumably constructed during previous roadway development and/or lot development in the early 1900's. The site is bounded by 6th Street to the north and two currently developed residential lots of similar size and character to the east and west. A moderate-sized church building is located to the southeast across an alleyway that boarders the southern edge of the site. MTC was provided with preliminary building plans and indicate that final grades will be approximately equal to present grades across the site. Construction is anticipated to consists of primarily of isolated column and perimeter footing members cut into present grades. Building design is assumed as relatively light wood-frame construction with slab-on-grade floors for the basement and detached garage. Projected loads are likely to be typical for the type and materials of construction, and no unusually large or vibratory loads are expected. MTC should be allowed to review the final plans and specifications for the project to ensure that the recommendations presented herein are appropriate. Recommendations and conclusions presented by this report will need to be re-evaluated in the event that changes to the proposed construction are made. 1 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 ProjectNo.: 18B355 1.3 PURPOSE AND SCOPE OF SERVICES The purpose of our study was to explore subsurface conditions at the site and provide geotechnical recommendations for design and construction of the proposed developments, including assessment of site infiltration feasibility and determination of design rates if applicable. Our scope of services was consistent with that presented in our Proposal for Services, dated November 7th,2018. 2 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 2.0 SITE EXPLORATION AND LABORATORY TESTING 2.1 SITE EXPLORATION Our site exploration activities were performed on December 14th, 2018. Activities involved observing excavation of four (4) machine-assisted test pits (TPs) in the vicinity of the proposed building site and potential stormwater facility areas. In addition, three (3) supplemental Dynamic Cone Penetrometer (DCP) tests were performed at representative locations near excavated test pits and at proposed building locations to help characterize in-situ soil strength conditions and provide foundation bearing recommendations. Subsurface exploration locations were selected by an MTC Project Geologist while on site to provide representative coverage for the proposed developments as possible at the time of the field visit. The relatively flat and unvegetated nature of the site provided for unhindered access to the test locations and provided sufficient access. All excavations were terminated upon reaching maximum equipment extent or planned termination depths at potential stormwater facility locations. All DCP tests were advanced until reaching practical refusal. Test pit TP-1 was excavated in the northwest corner of the site to the west of the proposed residence to assess soil for stormwater infiltration and was terminated at 6.0 feet below present grade (BPG). Test pit TP-2 was excavated at the NW corner of the proposed residence approximately 10 feet from the northern slope and was terminated at 7.0 feet PBG at maximum machine depth. Test pit TP-3 was excavated directly between the proposed residence and the detached garage approximately central to the site and was terminated at 7.0 feet BPG. Test pit TP-4 was excavated in the southeast corner of the site directly south of the proposed residence to assess soil for stormwater infiltration and was terminated at 5.8 feet BPG. DCP-1 and DCP-2 were advanced at the northeast and southeast corners of the proposed residence, respectively. DCP-3 was advanced at directly north of the proposed garage along the southern footing line approximately central to the structure. DCP-1, DCP-2, and DCP-3 reached practical refusal at 4.8, 6.5, and 5.0 feet BPG, respectively. All test pit and DCP locations are shown on the site map in Appendix B, Figure 2, overlain on current provided site plans for the proposed developments. Exploration locations are approximate, as based on hand-measurements and existing references noted at the time of the field work. Additional information regarding test pits and DCP exploration logs can be found in Appendix C of this report. 2.2 LABORATORY TESTING Laboratory tests were performed on selected soil samples in accordance with ASTM standards to determine index and engineering properties of the site soils. Tests included supplementary soil classification and grain-size distribution analysis predominantly for stormwater infiltration assessment. Laboratory test results are presented on the test reports included in Appendix D. 3 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 3.0 EXISTING SITE CONDITIONS 3.1 SURFACE DESCRIPTION The proposed redevelopment is located on a single, previously developed parcel located in the historical district of Anacortes along 6th Street. Development surrounding the site is generally single-family residences of similar size and style as the proposed redevelopment. The site is bounded by 6th Street to the north and an alleyway to the south where site access is granted. Currently occupied residences are located to the west and east of the site as well as across 6th Street to the north. Across the alley to the south is another residence and two large wooden church buildings. Topography across the relatively unvegetated site is generally level with a dominant slope rising upward towards the south from 6th street below. The site generally has a very slight northwest dipping slope with a small swale located in the northwest corner of the site at test pit TP-1's location. The dominant slope at the north end of the property is moderately north-dipping and accommodates approximately 4.5 to 6 feet of elevation between 6th Street and the overall site elevation. Vegetation on the site consists of well-kept grass with small deciduous trees located sparsely along the east and west site boundaries. 3.2 AREA GEOLOGY The Washington Geologic Information Portal published by the Washington State Department of Natural Recourses (DNR) indicates the project site is located in an area that consists of Deming Sand as part of the Everson Glaciomarine Drift (Qgdm). This unit is described as having clayey silt, silty clay, clay, and clay-rich diamicton and locally contains lenses and layers of sandy or gravelly outwash. This unit is commonly subdivided into Diamicton containing mostly silty sandy clay with scattered gravel (dropstones) or clayey silty sandy gravel. The Washington Department of Natural Resources (DNR) Interactive Map indicates the unit to be extensive in the areas surrounding the site. Shallow soils are mapped by the USDA NRCS Web Soil Survey as Clallam-Urban Land Complex, with 0 to 8 percent slopes. Clallam-Urban Land Complex is mapped typically on hillslopes with the parent material being glacial drift. A typical soil profile consists of 11 inches of gravelly ashy loam overlying very gravelly loam that extends to 27 inches with very gravelly sandy loam extending to approximately 60 inches. It is a member of Hydrologic Soil Group C with a very low to moderately low capacity to transmit water. The depth to restrictive features is more than 80 inches although depth to densic material is listed as 20 to 40 inches. Soil conditions consisting of sandy silts to silty sands with generally shallow depths to dense material were broadly consistent with geologic and soil map resources, although significant variations were observed locally due to fill deposits related to previous development. 4 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 3.3 SOIL CONDITIONS A general characterization of on-site soil units encountered during our exploration is presented below. The exploration logs in Appendix C present details of soils encountered at each exploration location. The on-site soils are generally characterized as follows in stratigraphic order to depth: • Topsoil—Organic Silty Sand with Gravel, Silty Sand (OL-SM): Topsoil was observed at the surface at all test pit locations and were typically encountered as silty sands with gravel and locally silty sand having high organic content and being dark-brown in color. Topsoil deposits ranged from 0.9 to 1.3 feet thick and were occasionally found in loose and damp conditions. Trace trash refuse and charcoal indicated some degree of mixing during previous development and landscaping. • Historic Fill—Sand, Silty Sand to Sandy Silt (SW,ML-SM) Uncontrolled fill was observed in test pits TP-2 and TP-3 to extend to 3.6 and 3.7 feet BPG, respectively. Historic fill soils were found in loose to medium dense and damp conditions and were generally medium brown. These soils were interpreted as fill due to the presence of trace trash refuse scattered within the deposit, the presence of large charcoal seams at depths unreasonable for fires, and due to the presence of large (—l' dia. Cobbles) being encountered at depth. • Fine Subsoils—Silty Sand (SM): Fine-grained sandy subsoils consisting silty sands with clay were encountered in test pit TP-1 between 0.9 and 3.5 feet BPG. These soils were found in medium dense and damp to moist conditions. The fine subsoils were light brown to orange-brown with moderate oxidation staining was present throughout the horizon. Roots were present in the upper portion of the horizon. • Coarse Subsoils—Gravel (GW-GM): Coarse-grained gravely subsoils consisting of well-graded gravels with silt and sand were encountered in test pit TP-4 from 1.3 to 3.3 feet BPG. These soils were found in loose to medium dense and damp to wet conditions. The coarse-grained subsoils were generally stained to a reddish-brown throughout the horizon. • Glacial Drift—Silty Sand, Sandy Silt, and Sand with Silt(SM, ML, SW): Present at the base of all excavations were glacial drift soils consisting of silty sands, sandy silty, and sands with silt. These native soils extended from 3.3 to 3.7 feet BPG down to termination depths ranging from 5.8 to 7.0 feet BPG at planned depths. The sandy drift soils were found to be in medium dense to dense or hard conditions and were typically dry to damp. Some small pockets and lenses of more silt-rich soils were found with depth at all locations. Trace amounts of reddish oxidation staining was encountered at all locations with moderate mottling 5 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 encountered in the upper 1.5 feet of the soil horizon in test pit TP-3 only. Generally, the soils were medium brown. Four DCP tests were advanced in close proximity to test pit locations at proposed footing locations to determine soil consistency and correlate data with soils observed in test pits. DCP-1 was advanced at the northeast corner of the main residence and indicated very loose to loose conditions extended to 4.5 feet BPG where soils became medium dense to very dense until termination at 4.9 feet BPG. DCP-2 was advanced at the southeastern corner of the main residence and indicated very loose to loose conditions extended to 2.0 feet BPG. Consistent medium dense conditions extended below to approximately 5.1 feet BPG where soils became progressively dense to very dense until termination at 6.5 feet BPG. Lastly, DCP-3 was advanced along the southern edge of the detached garage structure and indicated variable soil consistencies ranging from very loose to medium dense in the upper 4.0 feet BPG. Underlying the upper soils at DCP were generally dense soil conditions before termination on very dense soils at approximately 5.0 feet BPG. Results from DCP tests correlate well with the conditions observed in all four test pits with slightly variable soil conditions in the upper subsoils and/or fill deposits with conditions becoming firm at depths within the native glacial drift conditions. 3.4 GROUNDWATER CONDITIONS No surface water features were observed on site at the time of MTC's field visit. The nearest body of water is the Guemes Channel located approximately 300 feet to the north of the site. No seasonal channels or runoff zones were observed on the property during our field visit which was conducted during mid-winter season. Groundwater or seepage was not observed at any of the test pits excavated during MTC's visit. Moisture conditions were generally damp to moist and were considered dry at depth in the underlying glacial drift soils. The general lack of mottling within the lower glacial drift soils excepting the upper 1.5 feet of drift soils in test pit TP-3 may suggest that little water transmission occurs through these moderately to highly consolidated soils. Reddish oxidation staining was present within the fine- and coarse-grained subsoils present in test pits TP-1 and TP-4, respectively. The presence of rust-colored oxidation alteration along these horizons suggests that temporary perched water buildup or transient water flow occurs along this surface during rain events in the winter and shoulder seasons. No other mottling patterns were observed that would suggest perched water exists in shallow upper soils for prolonged spans of time. Therefore, we interpret the depth of restrictive conditions observed to correlate with the consolidated glacial drift soils conditions encountered at depths ranging from 3.3 to 3.7 feet BPG. Given the time of this investigation, during the mid-winter season following a generally dry week, it is likely that observed conditions represent a seasonally elevated but not necessarily peak condition of 6 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 groundwater occurrence. The above discussion shall be understood to be an interpretation of peak seasonal conditions and is based on indirect evidence of soil color patterns and our past project experience. MTC's scope of investigation did not include determination or monitoring of seasonal groundwater elevation variations, conclusive measurement of groundwater elevations at the time of exploration, or deep explorations that may have encountered the regional groundwater table at greater depths past the extent of concern for the proposed construction. 7 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 4.0 KEY GEOLOGIC CONSIDERATIONS This section discusses significant geotechnical issues that must be addressed in project planning and design. These considerations form the basis for the geotechnical engineering design recommendations presented in Section 5.0 and construction recommendations presented in Section 6.0. 4.1 GENERAL SITE SOIL CONDITIONS The results of MTC's surface and subsurface soils investigations indicate that the site is primarily underlain by a mix of fine- and course-grained sandy subsoils and/or variable fill deposits that overlie native glacial drift soils at all locations. Variable shallow soils consisting of topsoil, fill deposits, and fine- and coarse-grained sandy soils with an unknown depositional history are generally considered unsuitable for structural use and extend down to approximately 3.3 to 3.7 feet BPG. Fill soils were notably present in test pits excavated near the center of the site and extended down to 3.6 and 3.7 feet BPG in test pits TP-2 and TP-3, respectively. The loose and variable nature as well as the unknown depositional history of the fine- and coarse-grained shallow subsoils to the nearby uncontrolled fill suggest that these soils are inadequate for structural use beneath footings and slab on grade surfaces. An additional concern to the proposed redevelopment is the extent of previous development and the depth of disturbed soils caused by construction and removal of the previous residence. The following site preparation recommendations include a combination of overexcavation of the overlying unsuitably soft native and/or fill soils down to dense to very dense glacial till conditions below footing members. The site is considered to be generally feasible for onsite stormwater infiltration within the upper subsoils present at the potential stormwater facility locations. Presently, the northeastern and southwestern corners of the site will contain the residence and garage, leaving the northwestern and southeastern corners of the site available for stormwater infiltration. Soil conditions encountered at shallow depths in test pit TP-1 near the northwest corner of the site were generally fine-grained and are generally considered less feasible for infiltration than the shallow gravelly soils encountered in test pit TP-4 near the southeast corner of the site. The native soil conditions in test pits TP-1 and TP-4 were more closely assessed for stormwater infiltration potential via laboratory gradation testing and are discussed in Section 5.6. 4.2 SCOPE OF SITE GRADING A grading plan was not available to MTC at the time of this report. Based on discussions with the client, this study assumes finished exterior site grade will be approximately equal to current grade. Therefore, depths referred to in this report are considered roughly equivalent to final grade. 8 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 4.3 TEMPORARY EXCAVATION CUT SLOPES, SHORING,AND DEWATERING Plans for excavation including temporary cut slopes and proposed shoring methods were not available to MTC at the time of preparation of this report. Excavations are anticipated to be generally shallow excepting deeper cuts beneath the northern end of the main residence during construction of the basement level slab and foundations. Excavations exceeding 4-foot depth may require one or both techniques to be used. Section 6.3 provides general recommendations for treatment of temporary excavations. MTC can provide further consultation, design, and evaluation services for cut slopes if desired prior to and during construction. If shoring is required beyond typical OSHA standards, MTC can provide geotechnical engineering services for shoring design upon request. Dewatering to a limited extent may be necessary for deeper excavations if construction occurs in the wet season or during prolonged wet weather due to the potential for perched transient stormwater over restricting native glacial deposits at depth. General recommendations for site preparation and wet weather construction are addressed in section 6.1.3. This study did not include a hydrogeologic evaluation necessary for accurate appraisal of site flow conditions or volume estimates. It is only generally suitable for planning and design of dewatering methods. 9 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 5.0 DESIGN RECOMMENDATIONS 5.1 FOUNDATION FEASIBILITY Two requirements must be fulfilled in design of foundations. First, loads must be less than the ultimate bearing capacity of foundation soils to maintain stability; and secondly, differential settlement must not exceed an amount that will produce adverse behavior of the structure. Allowable settlement is usually exceeded before bearing capacity considerations become important; thus, the allowable bearing pressure is normally controlled by settlement considerations including differential settlement. Excess settlement due to adverse soil conditions may be a result of shallow or deep soils, or a combination of both. Preliminary design plans provided to MTC indicate that the structure will employ continuous perimeter and interior spread footings with a combination of slab-on-grade and elevated interior floors. Retaining foundation walls may be needed for basement-level construction within northern portion of the main residence depending on final footing elevations and structure design. Foundations and floors are assumed to be placed over existing soils or structural leveling fills where needed. Therefore, shallow soil conditions are relevant to footing and slab-on-grade construction. In our opinion, this foundation appears suitable given the following the recommendations provided below are followed. Native soils encountered with depth across the site include glacial drift sandy and silty soils found in medium dense to dense conditions and are considered to be suitable for the proposed residential development. This assumes loads are typical for the type and materials of construction, and suitable preparation measures are applied to verify subgrades are suitable at any given foundation location and grade. The variable shallow soils consisting of topsoil, fill deposits, and fine- and coarse-grained sandy soils with an unknown depositional history are generally considered unsuitable for the proposed development and MTC recommends that these soils be remove beneath footing members. Suitable glacial drift soils were encountered at fairly consistent depths between 3.3 to 3.7 feet BPG across all four test pit locations. Additionally, DCP test results from along the eastern side of the main residence and along the southern side of the detached garage indicate that similar medium dense to dense conditions should be encountered at similar depths (approximately 2.0 to 4.0 feet BPG). Explorations of this study were limited to test pit excavations and DCP testing which encountered practical refusal at all locations. Given the anticipated building loads and style of construction, as well as the underlying dense/hard glacial soil conditions present at the maximum depths explored, settlement from deeper conditions is not considered a tangible risk to the proposed development. The following recommendations presented in the remainder of this report pertain to shallow foundation construction and standard earthwork preparations. These recommendations are provided based on the results of site investigation to date and our understanding of the project scope at this time. to Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 5.2 FOUNDATION RECOMMENDATIONS MTC recommends that all topsoil, fine- and coarse-grained subsoils, and uncontrolled fill overlying the native glacial drift soils be removed below all footing members. MTC encountered silty sand to sandy soils containing some trash debris, buried charcoal deposits, and areas containing high organic content interpreted to be historic fill deposits. The historic fill deposits were commonly loose/soft, wet, and uncontrolled in nature and are considered unusable for bearing structural loads. Additionally, silty sand soils with clay and gravels with silt and clay were encountered at shallow depths in test pits TP-1 and TP-4, respectively, are considered unsuitable beneath footing members due to their variable nature and potential to be fill deposits placed during prior site development. Therefore, foundations construction shall consist of overexcavation down to underlying native silty sand and sandy silt glacial drift deposits found in medium dense to dense conditions. Foundation subgrade preparations shall conform to the recommendations in Section 6.0. Assuming site preparations are completed as described herein, we recommend the following: • Allowable Soil Bearing Capacity: 2,500 pounds per square foot (psf) for footings placed directly on recompacted medium dense to dense native glacial till soils consisting of silty sands to sandy silts, or on compacted structural fill placed over these soils on an as-needed basis per the recommendations presented herein in Section 6.2 for Structural Fill Materials and Compaction. If a minimum 24-inch section of structural fill is placed beneath footings,bearing capacity can be increased to 3,000 psf. 3,000 psf capacities may be used for footings bearing directly over dense/hard native glacial soils at depth, such as for a full basement level if planned (roughly 4 to 4.5 feet deep per DCP data). Soil suitability for use of this higher capacity must be verified during construction. The allowable bearing capacity may be increased by 1/3 for transient loading due to wind and seismic events. • Minimum Footing Depth: For a perimeter and spread footing system, all exterior footings shall be embedded a minimum of 18 inches and all interior footings shall be embedded a minimum of 12 inches below the lowest adjacent finished grade, but not less than the depth required by design. However, all footings must penetrate to the prescribed bearing stratum cited above, and no footing should be founded in or above organic or loose soils. • Minimum Footing Width: 11 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 Footings should be proportioned to meet stated bearing capacity and/or IBC 2012 (or current) minimum requirements. For a shallow foundation system, continuous strip footings should be at minimum 18 inches wide and interior or isolated column footings at minimum 24 inches wide. • Estimated Settlements: We estimate that the maximum settlements from shallow bearing considerations will be approximately 1 inch, or less, with a differential settlement of'A inch, or less, over 50 linear feet. Settlement is anticipated to occur when the load is applied during construction. • Lateral Load Resistance: Lateral loads can be resisted by passive pressure against buried portions of the foundation elements and sliding resistance along its base. We recommend an allowable lateral pressure equal to that generated by a fluid with an equivalent fluid weight of 220 pcf EFW. This value assumes footings are backfilled with structural fill and includes a factor of safety of two. The upper 18 inches of soil should be ignored unless the area is paved or covered with concrete, due to soil softening associated with freeze/thaw cycles. For footing elements placed directly against firm native soils,we recommend the allowable lateral pressure be reduced to 125 pcf EFW. Sliding resistance between the footing base and subgrade soils can be accounted to lateral resistance; a generalized friction coefficient of 0.20 is recommended for use. This value assumes concrete placed directly on the subgrade and includes a factor of safety of at least 1.5. If sliding resistance is required for foundation design, it may be preferable to place at minimum 12 inches of structural fill below all footings, which will allow a higher friction value of 0.35 to be applied. • Footing Drains: Due to the potential for perched stormwater in the winter season, MTC recommends exterior foundations employ footing drains to help maintain unsaturated subgrade. Footing drains should employ 4-inch minimum perforated pipe and be backfilled with free-draining material (as specified below for wall drainage) wrapped in filter fabric. Footing drains should be tightlined separately from roof drains to a catch basin system or suitable discharge point at least 10 feet from the structure. A schematic illustration of a typical footing drain is shown in Illustration A. 12 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 Foundation Backfill: Interior Floor Slab Impervious Upper 1 foot Final grading per project specifications Stem Wall :F:;' ::%;? ?,....: • ::?. •? r;::,?:c??;'::, :• Filter Fabric Wrap ;'1• Drain Rock 4-inch Diameter Perforated Pipe Footing ..ti. (graded to drain by gravity) Illustration A. Footing Drain Schematic Profile 5.3 SLAB-ON-GRADE CONSTRUCTION A slab-on-grade floor is assumed for the basement portion of the main residence as well as the for the entirety of the detached garage. The interior floor of the basement is assumed to be subject to light live loading from foot traffic and typical residential dead loads. The garage slab will receive higher loads due to traffic loading, which is assumed to be accounted for separately in the structural design. After stripping of organic soils, uncontrolled fills, and removal of obvious loose or soft subsoils, slab subgrades should be verified as firm and unyielding and native coarse-grained soils should be recompacted prior to applying slab base fills and/or capillary break materials. For traffic-loaded slabs, design and construction of the slab should counteract the potential for differential settlement due to soil variability at shallow depths, including use of reinforcement within the slab and additional gravel base for greater underslab support. MTC recommends the below activities and parameters for slab-on-grade design and construction. • Subgrade Modulus: A Subgrade Modulus (k) of 100 pci is recommended for use in design of interior slab-on-grade floors constructed over native subgrade of suitably firm or medium dense quality (including 6- inch minimum recommended capillary break of angular rock of structural fill quality). A Subgrade Modulus (k) of 150 pci is allowed for use in design of slabs constructed over imported, compacted structural fill of at least 18-inch thickness (including 6-inch cap break). • Proof Roll: Prior to placement of capillary break material and slab construction, the proposed slab subgrade or structural fill pad, if installed, shall be proof-rolled to confirm no soft or deflecting areas are 13 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 present. This is to ensure the existing base is evenly prepared and adequate for support of the slab. MTC recommends that we be contacted for observation of the proof roll or to utilize other methods of assessing the soil consistency in areas where proof rolls are not possible in order to provide a final visual confirmation of prepared base suitability. Areas of excessive rutting, pumping, or yielding shall be excavated and backfilled with new structural fill as described herein. • Capillary Break: A capillary break is recommended to maintain a dry slab floor and reduce the potential for floor damage resulting from shallow perched water inundation where slabs are constructed over native subgrade. To provide a capillary moisture break, a 6-inch thick, properly compacted granular mat consisting of open-graded, free-draining angular aggregate is recommended below floor slabs. To provide additional slab structural support, and to substitute for a structural fill base pad where specified, MTC recommends the capillary break should consist of crushed rock all passing the 1-inch sieve and no more than 3 percent (by weight) passing the U.S. No. #4 sieve, compacted in accordance with Section 6.2.2 below. • Vapor Barrier: A vapor retarding membrane such as 10-mil polyethylene film should be placed beneath all floor slabs to prevent transmission of moisture through the slabs where floor coverings may be affected. Care should be taken during construction not to puncture or damage the vapor retarding membrane. To protect the membrane, a layer of sand no more than 2 inches thick may be placed over the membrane if desired. • Loaded Slabs and Structural Design Considerations: For slabs proposed for loading due to heavier storage or vehicle parking/access, such as a garage, we recommend these slabs be designed for increased rigidity and self-support in order to help counteract the increased potential for differential settlement under loading. MTC suggests at least a minimum unreinforced concrete structural section of 6.0 inches be employed, or as specified by the project engineer. It is generally recommended that such slabs incorporate reinforcing to help span localized areas of variable soils and eliminate potential cracking. In addition, these areas may call for minimum structural fill sections to be placed to support traffic loads. MTC typically recommends at minimum a 12-inch section of structural fill base be applied below structurally loaded or traffic-loaded slabs, consisting of gravel borrow or a similar material of equivalent function as approved by the geotechnical consultant. Capillary break material can account for a portion of the base section if composed of compacted angular material as recommended above. 14 1 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 Slab design and specifications for structural or traffic loading should be assessed by the project engineer. MTC recommends that we be contacted to review specifications for heavily loaded slab-on-grade areas if present. 5.4 RETAINING WALL DESIGN Foundation retaining walls may be planned to facilitate basement-level construction depending on the final structural design (full building details not provided). Walls may retain either undisturbed native cut soils or structural backfills depending on layout and design requirements. All walls are assumed to be founded on suitably firm intact native subgrade, or on compacted structural fill, in accordance with the recommendations for foundation design presented in Section 5.2. The below recommendations pertain to the design of rigid, laterally loaded retaining structures. Values assume walls are backfilled with approved drainage fill and granular material, and retaining a level slope. These values are not universally applicable to exceedingly sloping backfills, backfills composed of non-granular soil materials,braced or tied-back walls, structurally or traffic-loaded walls, or for walls greater than 10 feet in height. MTC expressly recommends that we review final plans and specifications for retaining walls to ensure consistency with the recommendations presented herein and to provide additional geotechnical consultation and recommendations as needed for final design and construction. • Wall Drainage: To preclude build-up of hydrostatic pressure, we recommend a mihimum width of 1 foot of clean, granular, free-draining material extend from the footing drain at the base of the wall to the ground surface immediately behind the wall. Native soils are not considered suitable as drainage material. Imported wall drain aggregate should conform to WSDOT Standard Specification 9- 03.12(4) Gravel Backfill for Drains or 9-03.12(5) Gravel Backfill for Drywells. A filter fabric suitable for use in soil separation and water transmission should be placed against the retained soil cut behind the wall to limit migration of fines into the drain corridor. • Backfill Soil—Structural Fill: Where structural backfill is called for, soils used for wall backfill should be relatively granular with less than 5 percent fines (material passing the U.S. No. 200 sieve). Native site soils are not suitable for use as wall backfill. Wall backfill is considered Structural Fill, and additionally should conform to WSDOT Standard Specification 9-03.12(2) Gravel Backfill for Walls. • Backfill Compaction: To prevent build-up of excess lateral pressures, over-compaction of structural fill behind walls if installed should be avoided. However, a lesser degree of compaction may permit excessive post- construction settlements. In order to limit wall pressures resulting from over-compaction of wall backfill, we recommend that backfill within 5 feet of a wall be compacted by small, hand- 15 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 operated compaction equipment placed in 6- to 8-inch maximum loose lifts. Compaction efforts should begin along the fill edge closest to the wall and progress away from the structure. • Active and At-rest Pressures: Yielding (cantilever) retaining walls should be designed to withstand an appropriate active lateral earth pressure, whereas non-yielding (restrained) walls should be designed to withstand an appropriate at-rest lateral earth pressure. The at-rest case is applicable where retaining wall movement is confined to less than 0.005 H, where H is the wall height. If greater movement is possible, the active case applies. A wall movement of about 0.02 H will be required to develop full active and passive pressures. These pressures act over the entire back of the wall and vary with the backslope inclination. For retaining walls up to 10 feet effective height (including backslope) and retaining native soils or imported structural fills, we recommend using the parameters for active and at-rest earth pressures (given as equivalent fluid unit weights) provided in Table 1. Note: For undrained wall scenarios, if required, design loads should be compensated to account for saturated soil conditions and hydrostatic pressures per IBC. In this event, MTC should be contacted for further consultation. Table 1. Recommended Earth Pressures for Wall Design^ VERTICAL LATERAL FRICTION ACTIVE AT-REST SOIL TYPE(ASTM) BEARING BEARING COEFFICIENT PRESSURE* PRESSURE* CAPACITY PRESSURE Upper Soils (SM,SW,ML,GW-GM) N/A 190 0.30 42 62.5 Loose to Medium Dense Glacial Deposits(SM-ML, ML-SM,SM) 2,500 -3,000 195 0.35 37 53 Dense/Hard Structural Fill(GW) 2,500 220 0.35 35 55 Compacted Backfill *Values in equivalent fluid pressure,based on depth below grade. Units of psf per foot. A All values assume drained,non-saturated conditions. 16 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 5.5 SEISMIC DESIGN PARAMETERS AND LIQUEFACTION POTENTIAL According to the Liquefaction Susceptibility Map of Skagit County, Washington and the accompanying Seismic Site Class Map (Palmer et al., 2004), the site location is on the border of areas identified as having a low to moderate liquefaction susceptibility. Liquefaction is a phenomenon associated with a subsurface profile of relatively loose, cohesionless soils saturated by groundwater. Under seismic shaking the pore pressure can exceed the soil's shear resistance and the soil `liquefies',which may result in excessive settlements that are damaging to structures and disruptive to exterior improvements. The accompanying Seismic Site Class Map (Palmer et al., 2004) classifies the project area as Site Class D, representing a relatively moderate potential for increased amplitude of ground shaking during a seismic event. Based on the results of site explorations, MTC interprets the site to have a relatively low risk of liquefaction due to the presence of thin sandy glacial deposits at shallow depths and dense and consolidated glacial soils starting at approximately 3.5 feet depth. The USGS Seismic Design Map Tool (available online) was used to determine site-specific seismic design coefficients and spectral response accelerations for the project site assuming design Site Class D, representing a subsurface profile (upper 100 feet) of generally stiff or dense soil. The parameters in Table 2 were calculated using 2008 USGS hazard data and 2012/2015 International Building Code standards: Table 2. Seismic Design Parameters—Site Class D Mapped Acceleration Parameters (MCE horizontal) Ss 1.080 g Sr 0.428 g Site Coefficient Values Fa 1.068 F, 1.572 Calculated Peak SRA SMs 1.153 g SMI 0.637 g Design Peak SRA (2/3 of peak) SDs 0.769 g SDI 0.449 g Seismic Design Category—Short Period(0.2 Second) Acceleration D Seismic Design Category— 1-Second Period Acceleration D 17 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 5.6 INFILTRATION RATE DETERMINATION Gradation Analysis Method&Results During site explorations, MTC collected representative samples of soil horizons at shallow depths among potential infiltration strata at considered infiltration facility areas. Final infiltration facility location and depths were not specified prior to field work and soils were sampled from all excavation locations at representative soils horizon depths. Laboratory gradation analyses were completed including sieve tests for stormwater design characterization and rate determination to supplement field observations of select soil horizons. Results of laboratory testing in terms of rate calculation are summarized below. Laboratory results were interpreted to recommended hydraulic conductivity (Ksat) values in accordance with methods of the Washington State Department of Ecology Stormwater Management Manual for Western Washington (SMMWW), 2012/2014. Standard correction factors were applied as noted in the reference documents. Data and Ksat values are summarized in Table 3 below. Gradation results were applied to the Massmann (2003) equation (1) to calculate Ksat representing the initial saturated hydraulic conductivity, as described in the 2012 DOE SMMWW Volume III 3.3.6.3. (1) loglO(Ksat) _ -1.57 + 1.90*D10+0.015*D60 - 0.013*D90 - 2.08*ff Table 3 reports for each sample the input laboratory values and calculated Ksat. Corrected Ksat values presented below are a product of the initial Ksat and correction factor CFT. For a generalized design situation, we have applied a site variability factor of CFv = 0.33 due to the general variability of onsite soils, with typical values of CFt = 0.4 (for the Grain Size Method) and CFm = 0.9 (assuming standard influent control). (2) CFT= CFv x CFt x CFm=0.33 x 0.4 x 0.9 =0.12 Table 3. Results of Massmann Analysis TP # Depth USCS D10 D60 D90 Ff Ksat Corrected Ksat (BPG) (%) (inches/hour) (inches/hour) 1 2.5 SM 0.013 0.066 0.305 57.0 2.62 0.31 4 1.8 GW-GM 0.138 24.59 66.48 8.6 14.77 1.77 18 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 Facility Design Rates and Discussion MTC understands the project stormwater system will undergo design pending the results of this study to confirm general feasibility, design parameters, and depth to groundwater or restrictive soil features influencing design. No design information was available at the time of this report. Assumptions of usable areas are based on our experience with past residential projects, and the provided layout of the reconstruction features. The areas presently considered for onsite stormwater infiltration include the northwestern and southeastern corners of the site where open areas will remain and infiltration facilities and pervious pavement would be considered. Soil conditions at test pit TP-1 in the northwestern corner of the site include shallow topsoil overlying approximately 2.6 feet of fine-grained subsoils with moderately to highly consolidated glacial drift soils encountered below. Soil conditions at test pit TP-4 in the southeast corner of the site include shallow topsoil overlying approximately 2.0 feet of coarse- grained subsoils with similarly consolidated glacial drift conditions below. Due to the infeasibility of infiltrating within the underlying consolidated silty sand to sandy silt glacial drift soils at deeper depths, soils within the fine- and coarse-grained subsoils were sampled for MTC's infiltration analysis. Soil samples analyzed included soils taken at 2.5 feet BPG in TP-1 and at 1.8 feet BPG in TP-4. Grain Size analysis methods based on SMMWW 2012/2014 standard calculation criteria yielded Corrected Ksat values ranging from about 0.31 to 1.77 inches per hour corresponding to the fine- and coarse-grained shallow subsoils found beneath topsoils, respectively. Due to the variable nature and contrasting infiltration capacities of the fine- and coarse-grained soils encountered at similar depths in test pits TP-1 and TP-4, two relatively conservative design rates have been provided for facilities designed in the vicinity of each test pit. Therefore, for the design of shallow infiltration facilities near TP-1, we recommend a maximum design Ksat value of 0.3 inches/hour, representing the fine-grained silty sands with clays encountered at shallow depths in the northwest corner of the site near test pit TP-1. Additionally, we recommend a maximum design Ksat value of 1.7 inches/hour, representing the coarse- grained well-graded gravels with silt and sand encountered at shallow depths in the southeastern corner of the site near test pit TP-4. These upper soils are not interpreted to be consolidated or compacted by glacial processes based on in-situ strength, and are considered eligible for rate determination via grain size analysis to be used at the discretion of the civil engineer. MTC considers the underlying glacial till conditions to be restrictive conditions in regard to the design and performance of an stormwater infiltration facility located on the subject site. Restrictive glacial drift conditions were encountered between 3.3 to 3.7 feet BPG across the site leaving approximately 2.5 feet and 2.0 feet of infiltratable subsoils below the overlying topsoils available for infiltationg the onsite stormwater load. Under this scenario, a 1-foot minimum separation between facility bases and restrictive conditions are maintained and is considered suitable for small-scale bioretention or roof downspout systems. 19 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 The final feasibility of infiltration facilities for the project and site, with respect to other development aspects, should be evaluated by the designer. The facility designer should also review the assumed correction factors per reference literature to ensure applicability with the proposed development, level of anticipated controls, and long-term maintenance plan. The designer may make reasonable adjustments to correction factors and the resulting design values based on these criteria to ensure design and operational intent is met. Use of the above rate for final design should take into account the noted limiting site factors, soil variability encountered, and depth to restrictive strata from the planned facility base. The project may be eligible for an increase in design rate if Pilot Infiltration Testing (PIT) methods are conducted, which is considered generally more reliable as a confirmation of actual field conditions and therefore can be applied less conservatively. In this case, PIT methods should be used once a facility location and depth is selected. PIT methods may also be required by the local municipality for final design approval depending on the style of design utilized. MTC will be pleased to conduct additional site exploration or PIT testing in support of final stormwater design if required. 20 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 6.0 CONSTRUCTION RECOMMENDATIONS 6.1 EARTHWORK 6.1.1 Excavation Excavations can generally be performed with conventional earthmoving equipment such as bulldozers, scrapers, and excavators. Where possible, excavations made within about one foot of finished subgrade level should be performed with smooth edged buckets to minimize subgrade disturbance and the potential for softening to the greatest extent practical. 6.1.2 Subgrade Evaluation and Preparation After excavations have been completed to the planned subgrade elevations, but before placing fill or structural elements, the exposed subgrade soils should be evaluated under the full-time observation and guidance of an MTC representative. Where appropriate, the subgrade should be proof-rolled with a minimum of two passes with a fully loaded dump truck, water truck or scraper. In circumstances where this seems unfeasible, an MTC representative may use alternative methods for subgrade evaluation. Any loose soil should be compacted to a firm and unyielding condition and at least to 95 percent of the modified Proctor maximum dry density per ASTM D1557. Any areas that are identified as being soft or yielding during subgrade evaluation should be over-excavated to a firm and unyielding condition or to the depth determined by the geotechnical engineer. Where over-excavation is performed below a structure, the over-excavation area should extend beyond the outside of the footing a distance equal to the depth of the over-excavation below the footing. The over-excavated areas should be backfilled with properly compacted structural fill. 6.1.3 Site Preparation, Erosion Control and Wet Weather Construction The primarily silty sand to sandy silt native soils at proposed excavation depth are fairly moisture sensitive and will become soft and difficult to compact or traverse with construction equipment when wet. During wet weather, the contractor should take measures to protect the exposed subgrades and limit construction traffic during earthwork activities. Once the geotechnical engineer has approved a subgrade, further measures should be implemented to prevent degradation or disturbance of the subgrade. These measures could include, but are not limited to, placing a layer of crushed rock or lean concrete on the exposed subgrade, or covering the exposed subgrade with a plastic tarp and keeping construction traffic off the subgrade. Once subgrade has been approved, any disturbance because the subgrade was not protected should be repaired by the contractor at no cost to the owner. 21 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 During wet weather, earthen berms or other methods should be used to prevent runoff from draining into excavations. All runoff should be collected and disposed of properly. Measures may also be required to reduce the moisture content of on-site soils in the event of wet weather. These measures can include, but are not limited to, air-drying and soil amendment, etc. Since the silt-rich on-site soils will be difficult to work with during periods of wet weather due to elevated soil moisture content, and frozen soil is not suitable for use as structural fill, we recommend that earthwork activities generally take place in late spring, summer or early fall. Dewatering efforts may be required depending on total excavation depth, season of construction, and weather conditions during earthwork. MTC recommends major earthwork activities take place during the dry season if possible to minimize the potential for seasonal high groundwater levels near proposed excavation depth, and to reduce seepage occurrences from perched water conditions. It should be understood that some amount of water seepage from shallow sources or perched lenses may be unavoidable year-round. 6.2 STRUCTURAL FILL MATERIALS AND COMPACTION 6.2.1 Materials All material placed below structures or pavement areas should be considered structural fill. Structural fill material shall be free of deleterious material, have a maximum particle size of 4 inches, and be compactable to the required compaction level. Excavated native soils consisting primarily of silty sand to sandy silt are not suitable for re-use as structural fill based on observed contents and consistency. Imported material can be used as structural fill. Imported structural fill material should conform to Section 9-03.14(1), Gravel Borrow, of the most recent edition (at the time of construction) of the State of Washington Department of Transportation Standard Specifications for Road, Bridge, and Municipal Construction (WSDOT Standard Specifications). During warm, dry weather, it will likely be necessary to add water to fill soils after residing in stockpiles if stored on site. Material properties including moisture content shall meet project specifications for the intended use. Controlled-density fill (CDF) or lean mix concrete can be used as an alternative to structural fill materials, except in areas where free-draining materials are required or specified. Frozen soil is not suitable for use as structural fill. Fill material may not be placed on frozen soil. The contractor should submit samples of each of the required earthwork materials to the geotechnical engineer for evaluation and approval prior to delivery to the site. The samples should be submitted at 22 Huber Residence Geotechnical Report Materials Testing& Consulting,Inc. January 10,2019 Project No.: 18B355 least 5 days prior to their delivery to the site and sufficiently in advance of the work to allow the contractor to identify alternative sources if the material proves unsatisfactory. 6.2.2 Placement and Compaction Prior to placement and compaction, structural fill should be moisture conditioned to within 3 percent of its optimum moisture content. Loose lifts of structural fill shall not exceed 10 inches in thickness; thinner lifts will be required for walk-behind or hand operated equipment. All structural fill shall be compacted to a dense and unyielding condition and to a minimum percent compaction based on its modified Proctor maximum dry density as determined per ASTM D1557. Structural fill placed beneath each of the following shall be compacted to the indicated percent compaction: Foundation and Floor Slab Subgrades: 95 Percent Pavement Subgrades (upper 2 feet): 95 Percent Pavement Subgrades (below 2 feet): 90 Percent Utility Trenches (upper 4 feet): 95 Percent Utility Trenches (below 4 feet): 90 Percent We recommend that fill placed on slopes steeper than 3:1 (H:V) be `benched' in accordance with hillside terraces entry of section 2-03.3(14) of the WSDOT Standard Specifications. We recommend structural fill placement and compaction be observed on a full-time basis by an MTC representative. A sufficient number of tests shall be performed to verify compaction of each lift. The number of tests required will vary depending on the fill material, its moisture condition and the equipment being used. Initially, more frequent testing will be required while the contractor establishes the means and methods required to achieve proper compaction. 6.3 TEMPORARY EXCAVATIONS AND SLOPES All excavations and slopes must comply with applicable local, state, and federal safety regulations. Construction site safety is the sole responsibility of the Contractor, who shall also be solely responsible for the means, methods, and sequencing of construction operations. We are providing soil type information solely as a service to our client for planning purposes. Under no circumstances should the information be interpreted to mean that MTC is assuming responsibility for construction site safety or the Contractor's activities. Such responsibility is not being implied or inferred. Temporary excavations in the existing various uncontrolled fills and upper native silty to sandy bedded soils should be inclined no steeper than 2H:1 V, unless approved by the geotechnical engineer based on observation of actual encountered conditions at the time of construction. Excavations within the lower 23 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 dense or very dense glacial soils can be planned up to 1 H:1 V. Applying lesser grades may be necessary depending on actual conditions encountered and the potential presence of water seepage. Steeper grades may be feasible in favorable conditions, but must be evaluated once exposed during construction. Heavy construction equipment, building materials, excavated soil, and vehicular traffic should not be allowed near the top of any excavation. Where the stability of adjoining walls or other structures is endangered by excavation operations, support systems such as shoring, bracing, or underpinning may be required to provide structural stability and to protect personnel working within the excavation. Earth retention, bracing, or underpinning required for the project (if any) should be designed by a professional engineer registered in the State of Washington. Temporary excavations and slopes should be protected from the elements by covering with plastic sheeting or some other similar impermeable material. Sheeting sections should overlap by at least 12 inches and be tightly secured with sandbags, tires, staking, or other means to prevent wind from exposing the soils under the sheeting. 6.4 PERMANENT SLOPES MTC recommends that new areas of permanent slopes including fill embankments be inclined no greater than 3H:1V. Permanent slopes should be planted with a deep-rooted, rapid-growth vegetative cover as soon as possible after completion of slope construction. Alternatively, the slope should be covered with plastic, straw, etc. until it can be landscaped. 6.5 UTILITY TRENCHES AND EXCAVATIONS The contractor shall be responsible for the safety of personnel working in utility trenches. Given that steep excavations in native soils may be prone to caving, we recommend all utility trenches, but particularly those greater than 4 feet in depth, be supported in accordance with state and federal safety regulations. Pipe bedding material should conform to the manufacturer's recommendations and be worked around the pipe to provide uniform support. Cobbles or boulders or uneven rock faces exposed in the bottom of utility excavations should be covered with pipe bedding or removed to avoid inducing concentrated stresses on the pipe. Trench backfill should be placed and compacted as structural fill as recommended in Section 6.2. Particular care should be taken to insure bedding or fill material is properly compacted to provide adequate support to the pipe. Jetting or flooding is not a substitute for mechanical compaction and should not be allowed. 24 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 7.0 ADDITIONAL RECOMMENDED SERVICES The recommendations made in this report are based on the assumption that an adequate program of tests and observations will be made during construction to verify compliance with these recommendations. Testing and observations performed during construction should include, but not necessarily be limited to,the following: • Observations and testing during site preparation, earthwork, structural fill, and pavement section placement, • Consultation on temporary excavation cutslopes and shoring, if needed, • Testing and inspection of any concrete or masonry included in the final construction plans, and • Geotechnical consultation as may be required prior to and during construction. We strongly recommend that MTC be retained for the construction of this project to provide these and other services. Our knowledge of the project site and the design recommendations contained herein will be of benefit in the event that difficulties arise and either modifications or additional geotechnical engineering recommendations are required or desired. We can also, in a timely fashion observe the actual soil conditions encountered during construction, evaluate the applicability of the recommendations presented in this report to the soil conditions encountered, and recommend appropriate changes in design or construction procedures if conditions differ from those described herein. We further recommend that project plans and specifications be reviewed by us to verify compatibility with our conclusions and recommendations. MTC also retains fully accredited, WABO-certified laboratory and inspection personnel, and is available for this project's testing, observation and inspection needs. Information concerning the scope and cost for these services can be obtained from our office. 25 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 8.0 LIMITATIONS Recommendations contained in this report are based on our understanding of the proposed development and construction activities, our field observations and exploration and our laboratory test results. It is possible that soil and groundwater conditions could vary and differ between or beyond the points explored. If soil or groundwater conditions are encountered during construction that vary or differ from those described herein, we should be notified immediately in order that a review may be made and supplemental recommendations provided. If the scope of the proposed construction, including the proposed loads or structural locations, changes from that described in this report, our recommendations should also be reviewed. We have prepared this report in substantial accordance with the generally accepted geotechnical engineering practice as it exists in the site area at the time of our study. No warranty, express or implied, is made. The recommendations provided in this report are based on the assumption that an adequate program of tests and observations will be conducted by MTC during the construction phase in order to evaluate compliance with our recommendations. Other standards or documents referenced in any given standard cited in this report, or otherwise relied upon by the author of this report, are only mentioned in the given standard; they are not incorporated into it or "included by referenced", as that latter term is used relative to contracts or other matters of law. This report may be used only by Mike Huber and their design consultants and only for the purposes stated within a reasonable time from its issuance, but in no event later than 18 months from the date of the report. Note that if another firm assumes Geotechnical Engineer of Record responsibilities they need to review this report and either concur with the findings, conclusions, and recommendations or provide alternate fmdings, conclusions and recommendation under the guidance of a professional engineer registered in the State of Washington. The recommendations of this report are based on the assumption that the Geotechnical Engineer of Record has reviewed and agrees with the findings, conclusion and recommendations of this report. Land or facility use, on- and off-site conditions, regulations, or other factors may change over time, and additional work may be required with the passage of time. Based on the intended use of the report, MTC may recommend that additional work be performed and that an updated report be issued. Non- compliance with any of these requirements by Mike Huber or anyone else will release MTC from any liability resulting from the use of this report by any unauthorized party and Mike Huber agrees to defend, indemnify, and hold harmless MTC from any claim or liability associated with such unauthorized use or non-compliance. We recommend that MTC be given the opportunity to review the fmal project plans and specifications to evaluate if our recommendations have been properly interpreted. We assume no responsibility for misinterpretation of our recommendations. The scope of work for this subsurface exploration and geotechnical report did not include environmental assessments or evaluations regarding the presence or absence of wetlands or hazardous substances in the soil, surface water, or groundwater at this site. 26 N. • M .a�1 �I, a1 ' ` _I. 'I r .C1111 ri l tit'11_._ , • I � 1. r.r .�..1 , , to }L 111411)...141t .....1 � + . • I-1 ,n 'r}+`er • PPI C`/ l is. -r' I I1 MM ; I ▪ �, t i l uj ,,, I r 111 I �,�3.' , r l I .�,f 11= , I I YYY"' tjl �1, • t Ir I• •..I—, = ^, � .-; r, t I Li II Lel !:� 1 Ij. t,1 1 .. r ro; , t • Iml V '`��E.Y 1 ht )II . : I M III , r111 ,�' �.�i'I,'�.w�� M �{�{' I 1 p4.1.14orw, ..00:. �:141 '1 O I191 ,�y`�T l T " W - , 10 bO 1I. 1� '. e �LAI I , �' 1 , li, l • S ,i • II '� ../ 1r,.... '."7 � ,-TI t41 . I L •,,j. ..�I: 111, 1 `� 11•� ras i.'Ipll� 1 1 ' , 1Pml //" In ,.:LJ NI I •, r - _ . iJI -. I L•bwl▪ l' i '�r'iIIIIiI I I,A . . L,, \ T�¢q TC , �I: I; ' '�.Y.$ 1tlil '. III ' I . 6 Y. . I . 't::;• ® U .. ar I , y • l I�' 73 � �' 4Ave" 1 , f ' ; II11I II ', ,{ I11{• I ?I I 1 � iil • °�L�7; -� .• ( �� ' nr •" II. {N , , I II1 n. e. f / yp :Y .r. I l" !' , rit .�r1.■1 ,, Ir rtI ' ,.r'YVX,��F {' lr ,.r , ' 1 Oatr� .y. • -) a... 1, �,y� {II'' Jr I ^1P b 1 1 J I 1 1! LL Il..r--._.. t'A, � - I I II HR YIY , y` I`� 11,'' ` II `t ♦ � , .t `.1 I �III1i . ,1§�, S t }qT , ; , , ' ; 11 � �rf', , : ,�". ' Ir r �� ,. III ' a (.' I. , I� �4. • • i�l t ,• I 1 I I! I '.a �t 1 ,. I 1 '�� 11 J'9',:1 I :Ai�� 17 . ly , }� i II• 1 Ilb /;J '.""' • I4.. 1 ��1�ylrly,( 1 ' 1'j IHI ' 'ILgIt �.;�Ir' I rl j, '} .. I �I ,1 4 1''' It Jl ' 1 �•i t '1i'. I''I .1 ' %j 1•. :„.i.. . ...f„ .• ,,,,,,,,i, .,„ 1 1 I ' h11l �I°I J Id ...0i., h i ;'11 ii ,' I . If. I ., .. C : ('ll'yli • ir,l'V; . ,,. . ' 1� . , ' T• yl7 t�„ f I ;. + ;IJ iu r � , _ • cep I II I �' i J .1 1. I 'I ♦ - a . Ifr I,Ib It I• I j1111 N. IMI I , r t. �� II 1,' - frN 1 irylii ' I ;+ll. ' • � ' I ' I I II}r ' �'"'r 1 � I I0111'�i - lily '� I' yI'I III Ill �' I i ' .I it j I, I I' II 14 Ili [ ry I A� ., ..4, .It '1 , 1 • I, I 1. 11%. IL.,• I. Irrl Iiii r,1I9� Illls. 0lI I IItl1sr1,'IICI.. I..r ,I { i • 1.yM v..,.. • 1 I 1 '• .,• I; ' TV• 1. J 1I I I ' , 115yr/. I1� _i•• ,Jy- + L-� 1, 1 I II I. Ijl 1• ..j ..�_} orb •I 4c . {'7'1 �Ii. 1. liQ�r , I.j I' A1''' I, I . 1 I . ll . '1 • ' 4.1 ~• �- •• 1 �1 • • I , I . 1, 1 .11r°,-_I /�� _ } 1. 1 I ! •J aill�. :,r I 11 I rll. r r Ihn �.ialy :. I ' y YI{, 1 ,. i - Ilyr 1. I II'✓ -• a, I�1 I I " Ii1 �-�1 ,I �� I r 1 tititiJJJ , I 1 y �i ". I , 71 ,1ilis.:; 1 , �.• r • t � I. ._ �j(,� I � gllfll�'^.'I IIr" ' 1FF\ ' • I•� tIlr � diujr c.- - W , I1�1+� 111 H:: CNII 1 �/ • ,' t • I,' II ' q 'f• ' I . I$ `I - _ " ..p.l" .. "I' ! .,j)• f1y�t • I d t , .lAt l i I1n1 ., i.,I I"FI 11 ,':" • �� i^ 1` rj I - Ill''' . L . 11. l ` r: : ,{ K:I I 1i� _ ' "' 1 , . t. .. k '•bl L I" I1 „ '' . Iy . ' • Jr - 1 i '1 '! I l'J ' r ' � F=� fli- --el.,�� i 11 �.l K� pp, 'I , 1{: I;IdL: 1 4 kr: • • ,11 ' •1. �I p It'{ 1F4J I 1 s �yr,l ?L4II: J' . 24 RI lill . l r1I 'r t I�I�IILI • dI 1i � ' I;{1Lj •I, I Ii :, r.41 : L /1 I _ „ I ':Ili II: . l p�'fl p 1, • {.I I i . • , • . tl '' r t I. IIJJ /J' • f,^c rtl•i .Arlu Vlil • 1 ,I11, • , i /1• I : . I :' IIIr 'I ul 11III1�A1 t�lY..1..• O ptitit ll/ 00.. Ave • • I I al < _ A1.. ' , I I I •..�.0 t. .1 r: I /��/ I . i)-, ./ � 1 1111 1'I I - - I VJ .Ls � Ii•_ I I , p . `a ' 1 . , ' . _ Vim' ll1' , I I �" 1 r l • !''I�',r i ti i 1•• ,A •• 1 , penni Grp I I it 1 11 ' %r • 1 IIIA 1y 11 wh. ..e.-.Iw.-...n.°w.,ll ) j ' � ' ' 1 , 1 I•... ;al' yy:�t�.,, 1 r'1 � 1. •I I • , 1 1 A 'LL I�Ip 1 , 'I 0 r� I. . . 7.,7.1 ' 1 IA,1•lo� p ' 1 i IIj' `P; I r I O A [ 1, H^ ' A N^ I ,I PI', I �, , ..... ..I I I,• III 1 ' I+ I 1 11 ' I' , Ia . ' a l ! `I' ' 1 "` • t • I + •�� ii's.r.- 1 •1 Pc . lAI ® c , 0-� 1 ll: 1 I 1; rf+ ,I y , Lj r 1• �... l ' O• Ij. A_ ;,�_ 0111 ri, I I +a ,.- I I� ' ' I �--i N ' s 1 • tr � 6T , X}rl 1 ' I,,rP� d1l t ! v ' ' 4 11 jy 3 1 II es III 1 ` �T , 111 1, 14 nI 1 1 i T f li lI�fcillik:111;:::: i r, il 1 II I I i; ' 1 J a �tl4I (`IL ',I I ` " ,�* I 'lt . . M.. , ,` • it i Iti.i i, l,�l I � ' i,1 ' i• Ili II.'`� j • '' I. ' I ' 1 .,j '� 1 II it) .1 Q. AI •n;l II " I 'I I 11 1 i. . Q J t 1 • �+wl I t ,l I t�, l it II l4' ' • 111 Il I I (,' it I' h ! I� - r.Ij �w 'I•.�1•A' , , 1 - I,1{ '.r: I , aiilf r I iiiUUU111.. Ir 1: i . 1/ \ I • - •I �� lr,l III i11 1 ram . ' �y l . I {I I - • 1 ; �•�I'�.A •- 11 C, 1,41i11'' Ilr T-1 gar ,(A '�(I I n 1�1t� . 111� II "a .. % l , " o• • • .. ........,..jLlr�t1Tl,,, ''' I + ih ' E /,;� P r 4 1 ' wl Il �, I r.+ Lr�. Sr.. d t I. �.� Cy 1 l Ili: r.A ' 1, 111. en • I It , ✓! I •• � 1 l�. ••r ` II . . 11 .1: III' t1II t �l. IY I !h f 1 , 1 i . 1 • , I i'!11'!iv", j ' ,.1 I' I . 1 !1 I+p \ 9 S'%. 1 jlu�� I I Art' / - 1 .1 1 ra I'ill I I I I . II 11 e 1 3 )' .I I , f.�likt; '� �I; --.-. . NI i ill, 1 11 I. I . I. ' ,,• '1„ O� r".. Pri - 11 I ..'. »,' ,`I r i11 1 �I' 1,1�1:. j •I j :,1�. III �'w N , I ' I rJ 1: }} I (/,, 1` I {, ' , y1 � �.j'I1• • 4RIt I1 �' ' �• Al .•r 'tj Ir ,�l`y 1 a. i 'IA5 FI { .II III I P 111 �. hY Y I I I 1 ' I Lrl ry , .i III' - �. !,• °� wo �� AAA�� •1 ' 1 1 1P :1 AN !1 I •� / 4:_1I tni V Q I C' ,I .I O I 111V 11 ;1. J ri. .,,. {I „ r—,I K1. , I II' °� y 1 1 ° {{{••��111 iiih 1, 1 ', I,. "1 S ,GA ('r.8. I �h I111 �.1itpu AF...y , LI II' '{'r /� � � T ,,q " j Ir I 1' ! ( rl Co) l �9 4 ki 1 ;1 p/I 1J 1....�,o.+ � I fa _— 11( r 9IlII ' I' 'j4. kW , j4 " II. II ,I[� r � , (. • I l • l ' III: . '',j 1 li !n II" I, O.'. 1' 1 r6 I ' • 1 /� 1""' VL1 1 r • 1 II ` .. I:SIIy 1 1'I I ! I la .a ' il, 1' 1 �, r I "Jiro Alt. i>• • (� ( r.,r'I I 1• ' -'.�'!w I ,I. r \ yll ��: I I F 1 'Ll'1 • ^1 o d �1J 1 yl 1 J � �, I' 1 1 ; II1 I I i. r I . ra... /. I r r rl ..1' II °� •.. •" I1�'I . l t.ri:w' _ ++ ,loi :1•'11.' ..: 1,4t tr j 11 1 , ,I ," • - . I I R r_ `,, i ' _ '�LI ��11I,,1'r�S �� - o + fl ' 1A1�^�/�� ClitI ii ( ,II ,I ' , ' 14 / I I ,� I 1 111..,' � �l/., . . r le. -' t I . I ,� ' r�I1 I ' t 41 It yT I .I. � I� Cid O 4 , JI ,,,�, '1• I r , 1 :1 1 , 1 .l . Ihl 61 I' , ' ,I'� I .w�� • ' ll� II• I "I - � ' t ' ' I{ 1 t1� • _ ' �I• ,' '.I I{:L J', II (r'. a �I L . I:JD vEb C • , ® �✓-1Jl • L I. f � " r 71 % 1 �✓ ~ro Ii .. , , 11 \I L�I'� /■I I ill. I I .J I + 1 )I II' F I :I y -j1' 1 'I r = O / ' � I , ! 1 ,1. 114••,7 . V•IJ I I 1 I r 1�1 1 i t,n. {p'��}StI''1 ITI �ykll ,•Frl ti � I ,11�A 1� .I t ' IH �/� (_j �.. . I , 1' 1 ; • f I 1 ., .JI I� I1. �jlle•+A'.11r.r x11 �Y 'I , II ...1..1 1I ry 1 -• "',.,.__.-•. . ' ,E/1((II corJ • `) [��Vt[��/.`•'111 /\F1f - • . , /�/.. ' 11 I ' :� 1 I 1• 1, +� ii, ryn1,l,py 11 j� r I i I ' (�1' II �' I 1N rl e/ V ` \_ / •� 1 :1.�, '" VI. 1 ! 1 y ibl 1 • ,1 ' 1 ' Z I III I �.I it). . �tp • I I °� "L n I� \y ♦� pal � 'y i , \4' • II - H It 1 ..I 1 1 ' . , . 1 ^ N 1 t f ' .,. I r-1 II1.1' r�...�/!� 1 wh. "Oy J/� I `dye �',r t * f a r 1 1111Y✓1.. , . ..,. . 10,2:z �:C ,, I 1 -V'J , . I 4p� l •z Irs YI•N•1 I. 1 ,i 1:' w I *i • I ■■ '' 444{r�.1.I(� i I. 1 1 13 ^ o .1' _ I o 1=_I n 1'1d i .r , � h, '� - Jig: 1. ,.II F _ 1 .ail , . /.�' 1 oV O `�� v :_ N ' ' I 4.1116 I� Sli i-C7 f I t�j. I I . . I Al I' {, 11 F J,/l �I +.n M'd { Q it •—I / , , I, 1I .. , �{' '.I 'At:.. � I J� r .. - ..r). • n liI , !_ I , I p Q 1 , to) _ •.h y',1. iII "•- 1' 4 }I'� yy//��.....�.� , �� / ii Ste_,.... I b t� • \�1\`11 °tag ( ' l I I ,� I 1 ' IF°I ' I ^ �!�y I" I tooral ,o a Z • H • e u 0 f r • C> 1'11 ' M • ' • Call, �° °° ill w N • x *14 • = Z Cr • CA IF w o 4 .. I 1:: 1 V • '�"i , 1. 1, j r .. [A1�--IC " I a i . .I M � ., 111VI� I 1 fie& CA ��// 11I r ., yl1 .r1•ALLS„•Ilw.l•I�r'a•�r�_ y _ l 4 I,111� It ,�,.1{9�� '' • it Il 11�t j1 1, I �V� 7!/If _ • • ti ' I� 1 •'1L• 11�1} � 1, I,' 1 1�1 (�il I. { I IY al1 r1j all 416�� I ! • - �, i1• 4.41 Illkal 44 �l (• 1 1'' t1'j1 ,I ' •1 "li•f i vj, �I(' O ft) EMI • at.,.., 9' ' , l 1r I 111(. : �, ' 1 111I f " I 1tWIh 11 It it ,11111 P 1f 11 1r III /II � . .'' 1 • n ,• ! 1i ,, 1 1111•r°., 4. 1 1 1 1 fl l 4 ` 1 1 , I • .I 1 ( � � �11l,, I ,1 /' ,f ,tt . tl , I 1 1i �r - •If/ /�� 11 I lr • f 11, r 1ft 1' , 41111.1. lV/ � ._ � _. Y1� 11 WI 1. 1 1 Ill p 'I ' I 1 • 111111111 fl ' • 1 • 1 1 {'1 'I •II 7 r ICr '1,1��/II 11/11 I, II) I j,{ Ir 1 4 .�' Il , • l I �t ' Y,ti f1 /111/ 11111 1 'i'%' , Y 1 !1 i 1; 111I '1 l ,1 1'�1i�� t 1• 1� 1' 0 Immil �..t0.0 ' . .P II I )'yi i1�11 {I ( IJI llyl , I - III ' a'I L �• � '!� fl 11 }I f 1 1 'j.11 1 1 I II i1� , •1.. a1 14 11 L . "1 1,•J'1 r, I CAI II ,1 1 ..1 a J11 vl • ) I6 ,•I �pl 1 • •MA • II • 'I'114 . ' III •J 11 1; I " 11 1 l,f IIIn II 11� � II It �., 1 , 1 I ` 1 r ( ,'1 I 1 I Ir Il ) 1 f I • i 1 •1 I � • 01 "Y9 I ' i11 ) 1t i 1"II ' �4 i 11 �� I tI •%`Jt 11', . Cla i ' I( - ' 11 I 171 'r 1 " )t I tf ,I 1. 41 'j l Il t r �'. i „ . I //�� 11. , l�Lrli I h . II 1 '1'1' /. , 11 I 1{I I::"I I ^ j,t 1 1�•'q{Ir l 1 , I' '• \r ' dl, ' I1171"' 111 , 'I ' r1jl II 'I).1II♦l I I' ) tI '�I 1f•( 'P1fft I171I1��i1).,' ' 00 I I f ly , I. . '. 5 1 is' OF l 4 1 u•. 1 r,�l 1 . • CD • 1 I 11 •11 ! Ohl I I I1111 . I 1 f� 11 +III I I' a 1 111_ I. 1I11fI�PJI4 II tl urr i I __• IlI1• .� " irIu . r I' Ir ♦ Yy O ii I 'l'14 Y ' 1 / 11 It1I 1 1'I)f 1 t r1 1 1 /{ fJi,1,1 ' 1 1�C . ' 0 . r j' •, 11 I Iq tl l'../I I 6 .. 1 , Ilr ld. I I,f ll I! lu L .. • 141 1 H' 1 ill 1 I . 11 I 1 III 4,• 4I a . I 1' l t �1 4L,1 ('1 : f 4 r, I II, 1 ,1 tvr I I r 11114...1 ! 1 I 1111711 I I Il fj I" Il jl I l ; I if lu Il 11 �-�/� )1111.4 Mit'l ).i I I loll \!{ I ,ff llil' I� I �� ' 1 �� '� f 4 j� h I - V 1 1 Ily' I hl 11111 1 I V II 1 1''111.y II 1) r 11 it rp III1y11 rI II f ♦• I"' ' I e SiII 1 I111 1i a1 ' S 1 r , I n141 11 17 'i h I I hlI . ... 77 ' 11 , 1 � t II 11 1 1 I' p II 11 y 11 2 I I 11 'I' - 1� ' I • ,I, 1 •1 lr I , { lI 1I I I .I � , IS , 11�P Iljl�r III (l { I(• 'I 1.5 1 ' I Il I• l f ' 1,. ll ( ,I I1 1 ., IItII, I .I r• t 11 J 1p11 I(, I I,• - I 4 i U • • f,l n 11 • 11 ' ii111 • 1, { r I- I .III lei. I 'Il 1 '1 ! )1 ) I ' 1f rl( 1' ' n • 01 cn ), �l • 'I I y II II , ,I I I f , f1 IIL1 1 1 ' I • ri"r 1 1 lltt r II • 1. r 11 + 1 1''I 4.I'1 cal , . I I 1 .1 ' g111 YI ' I 1 11 • '1' ' ' It l;brI I I I(, I ' III I . •I? t I. I' C6 ttr i ' ^ � II II . 1 • 11 ' i. '1'III 1• l1VV ;III IIIII Ir.• 11' 11 � II•t1 ' i1 111,'If I IIIIr IIt11 j� Iil I . . i� t 1 11 ,I II it 1 1 111 I I ( I I 1 • I�11 , tc.„ 11 1 • • j I r 7 ' I / r v I ' IIII'1 1 11 l iil , 1 I 111 ) I I ,' • I I ,I 1 .l 5 1 b 't 1ti /'I :It 1. )I II1 . , , .1 . , f 1t1 � , I i 1 I l• II Ip t',II 1 ' ' ' 111 1 • I 1 ' 11 I Ilf/1 , ,f • ��\\I 111 '' 4. Y I I,'0 ' 1 . .11.1,'�r dl I ! II 1 p II I:11�1 11 IIII1� I 'Af I�It . f� 0 r.:2_4• I t 1 , 1 I .no. 1 . Ir, - I I 1 p 11 1111 hl I. " I ip, i" ,y 11 • r�1 , . ' 1 ',I.E.' tI •'11 1• r 11.•I1111 •,. Ii 111 it,. . , • II I la it t 11 p 1, ' IfI tl 1 1 1 I I • t it,. ! t I 1 L1, 111 1 Cid i l 1 I µII I'1:' I f ! 1 1 1 O I 111!'I ' ! il" '11 II ' 'I 11 'I I I ' ' I;I ; 1 Ill t•li„ ill. 1 ' ' , U,III 1 I 1 ' II 1 j,1 1111 ' i �11• 1 I I. I I pl r !• I f1. '1, • i I' ;lit:, 1 1 '• ' i I I i r i 11 (1 , I III •, I I I 'r I. 11 ' 11• ' 11 ', 11 I ! ',1'llll I I l , '1 I 11 `'111 Ili llt " I ' 1llj 1 11j' 1 IPi 1 ' tl11. �ISIIC 11 1 ' I ' 11 'I I1 lIt Ij , I • '• 1111I I . I I''1 111!4 1 t y I 5 11111 ' I Iy EIMIIIII • '11 • ' ' I iiIl • f I I 'i1111I'IJ %Iy1 ' • ..1., 1.1•1 11 i lil ' •"I 'i •• U 1 •1 I r •' • 1' 'I '1 • ' ' i '!' I I I ' d, 1 , • ' ' nPMI 11 I • • I I ' l l 1 l• l ' ' I 'I I . . 1 II P 'I •• • , 1 1 II l ' ( l ' { ' t I If l I ' III Ill, • I • , . I 11 ` I ^ , I, ' 00 g ' , {..�_ ... _.�.. ._. - .- .• _ ... �� .r..�.►-__.._ _ �_.. .a „ 1 15i ;.11. ' j I 111. 1 II � 11 II �I ; ' J,I IIJ, II II,III1 III IW 1r11 II ( 1 1 ` V . II „Is.l I . I I 'I It• • d' 1 ,f I 1 1 I •' jI'„I 11' .i 1I 11 7 — _ .� 1 ' Mf'Irl i .1';''.,I j I ' a •I 'I' ' 1 ' i _III ^' I1 ,, p a r/� • I y. t I' 711..4 y. .;. 1 ' . r �r ' 1 1111• r 1 ';. I , I {11•11a �I1 il I r r I I .: I . • , I . ,I , 1 NI , r�. l 1 •-- Pk ,, 1 /I I . 111 ..A 1, ! I I s5 . ' I ' ''. 1 ' I; I- I'• , 1 'I I. I , 1 f 1 11 • • .1• 11, • r'• 1'1 I II , �.r yf • 1 I , t • +J. • , I',i�II ly III •1 � �'' li ' 11 I Pi 1'11 11 11 IS ' 'I 1%1�• ' 1' `' 1 • 1 ,• . �' ♦ 1 I ' ;yf,l I . C • . • ' ,11 ' '.1 ' iii 6 ' I:. ''I llifl " • 1 1 1' 1 % ' ill' �. • L II ' t I ' 1 1 lrlrr IJ J P Y.rtrl t j• * • 1 ^ IIi 1u • ,• 1 1.1i •f , 'I,I I• I I t 0. 11i* V I ! 1,• ' • 1'' • _,/ __ 0 Wool II I . 1 I 1j ' I • 7iiii iIL PIIII1 . 17 jl tll�l 11 II II I'• ll 1 q1 ' III ! 11 , i V,• - 1 1 ' ( I 1 (• '• 1) I I • 1 I ' II ' n 'rl I ' ri 'II 1 11 O1 ��'�./ J 1 rY• i f' ,III I 1 P //��y I4 14 ) 1 1 ' VV L. n • I 1 I ''1 ''i1 a ' 'I1 ''' ' 1Cen Iiis M 114 , ' 1 ' 11,1 ' •' ' 1 . • 1 11'1.'I , 11,E I 1 ej11111111� I is e ' i.{ , I ,r H. ' . ' 1J N 1 I II ' 1 r . ' 1 1 I,IIu r ;14 •I , ,'1P, O r • u M O .I I 11 f ;•'f11I .1 11,11. II 1 I .. 1 I 1 I '"dl jl II (, • �� CC I • r i .'1 I • 1 Igy'y� 'I 1�1 CS• CliC • O 111 I '' n • 1 1 ' r f` ' u 11li ''• �p'N1',tb /� I 11 IY I114 ,1' . ,1 1 r ' 1' t , F ' O • • ! ��11 t�jt I l'i' I 11 11 I 1 1 ', , I l' I • s �, `1 g PC4 P 1 1 ' I1 ,•., ,... • ,1 1II '1.1 7u CS) • I I • 1 1t (MIN ! , •� II '! • 1) ' 11 lid 11 '• 1 11',0.'I I �I r 1 • r� I tili�� rl• ' I , II r ' I1 .'I I 1 II I 11 I1i1 - I ' ( • 1 ' I 1 I I IQ. I L 'I . ' 1 1 1 1 - I ' I' I I `/ ///�� P 11I1b I • ,• 1.1 II d 'o r I , r 1� , VD l l -11 : 1 I �' U Cie 1 I'. I 1 II� ' I 1 • I is / {III 7 L I:IS f ' n I 1 1, 11 •l ' , , I • 1 , • q I 1111, I /� � aZ r _ • ' I I t , I 17, 11 111 n V'• • II I I ,I I '' 1 I V/ f•"( W. t ' I I r liS" t I y 11 �I I 1 rr.. I 1111 • paj 1}.r.l • '/—'-ry`, O 1 1 '- , {I 1' 'Lii •it 4 1 ) ' I it , f I I i .I p� • t, It' , I'1 1 1P . 1 I' f 1 1 1 ^ `l O • PM ,( / I, 1 ..Pt ' . 1. 1 1' yA •, n11'I 1` ` • I 1' I III . . 1 II.: 'I _,. _ • _ r U V/ �j,..� co) _�I • 1 'i f 1� f 1 1 ',Ili It, • 1 Ilf. 1 t 1 • I 1 1' 1 I' �' I� I,.j1 O COD • • 1 " • _ _ . - . ._ .... . . _ 1. 0 t bkv. 1 1 I. , , • • 0 . ii 8 • H 2 lie IMMI CD aill • I 4 c's,.., mit o , . ci. , , • • ,...., • pool • h-• I tlrV- 1V// umr ' CD • O z .r — . ._. • ► It g I - Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 Appendix C. EXPLORATION LOGS Grab soil samples were collected from each exploration location by an MTC geologist during test pit excavation. Soil samples collected during the field exploration were classified in accordance with ASTM D2487. All samples were placed in plastic bags to limit moisture loss, labeled, and returned to our laboratory for further examination and testing. Exploration logs from test pits are shown in full in Appendix C. The explorations were monitored by MTC personnel who examined and classified the materials encountered in accordance with the Unified Soil Classification System (USCS), obtained representative soil samples, and recorded pertinent information including soil sample depths, stratigraphy, soil engineering characteristics, and groundwater occurrence. Upon completion,test pits were backfilled with native soil tailings. The stratification lines shown on the individual logs represent the approximate boundaries between soil types; actual transitions may be either more gradual or more severe. The conditions depicted are for the date and location indicated only, and it should not necessarily be expected that they are representative of conditions at other locations and times. Penetrometer results from DCP testing are also shown in Appendix C. During penetrometer advancement, blow counts were recorded in 10-centimeter increments as a thirty-five-pound weight was dropped a distance of 15 inches. Blow counts were then converted to resistance (kg/cm2), standard penetration blow counts (N-values), and corresponding soil consistency, as displayed on the logs. 29 Huber Residence Geotechnical Report Materials Testing & Consulting, Inc. January 10, 2019 Project No.: 18B355 Unified Soil Classification System Chart Major Divisions Graph USCS Sampler Symbol Description 1 P Typical Description Coarse 0 •.o Li Standard Penetration Test(SPT) c GW Well-graded Gravels, Gravel-Sand Mix- Grained Soils Gravel tures Clean Gravels ._« : al Shelby Tube More Than • - GP Poorly-Graded Gravels, Gravel-Sand 50%of ; ;`-« Mixtures ® Grab or Bulk Coarse Frao- tion Retained GM Silty Gravels,Gravel-Sand-Silt Mixtures More Than 50% On No.4 Q- • 4 j California(3.0" O.D.) Retained On Sieve Gravels With Fines ,'i • 9d O.'7 . G�-, - No. 200 Sieve • :o-•-• ' GC Clayey Gravels,Gravel-Sand-Clay Mix .b tures II Modified California(2.5"O.D.) • • . • . SW Well-graded Sands,Gravelly Sands Sand • • . • Stratihraphic Contact Clean Sands Distinct Strati a hic Contact More Than . • •• SP Poorly-Graded Sands, Gravelly Sands Between Soil Strata 50%of •Coarse Frao- ` Gradual Change Between Soil •. lion Passing l • SM Silty Sands, Sand-Silt Mixtures Strata No. 4 Sieve =: Approximate location of Sands With Fines r: •' stratagraphic change . SC Clayey Sands,Clay Mixtures Fine Grained Ml-, Inorganic Silts,rock Flour,Clayey Silts y Groundwater observed at time of Soils With Low Plasticity exploration Measured groundwater level in Silts &Clays Liquid Limit Less i CL Inorganic Clays of Low To Medium exploration,well,or piezometer Than 50 , Plasticity More Than 50% of Perched water observed at time Passing The OL Organic Silts and Organic Silty Clays of ♦ xP No. 200 Sieve Low Plasticity 1mH Inorganic Silts ofModerate Plasticity Modifiers Silts &Clays Liquid Limit CH Inorganic Clays of High Plasticity Description / Greater Than 50 Trace >5 ♦ OH Organic Clays And Silts ofMediumto ♦ ♦* High Plasticity Some 5-12 * With >12 PT Peat,Hiunus,Soils with Predominantly Highly Organic Soils Organic Content Soil Consistency Grain Size Granular Soils Fine-grained Soils DESCRIPTION SIEVE GRAIN SIZE APPROXIMATE SIZE • SIZE Density SPT Consistency SPT Bloweount Blowcount Boulders > 12" > 12" Larger than a basketball Very Loose 0-4 Very Soft 0-2 Cobbles 3 - I2" 3- 12" Fist to basketball Loose 4-10 Soft 2-4 Coarse 3/4- 3" 3/4- 3" Thumb to fist Gravel Medium 1 0-30 Firm 4-8 Fine #4-3/4" 0.19- 0.75" Pea to thumb Dense Dense 30-50 Stiff $ 15 Coarse #10-#4 0.079- 0.19" Rock salt to pea Very Dense >50 Very Stiff 15-30 Saud Medium #40-#10 0.017- 0.079" Sugar to rock salt Hard >30 Fine #200- #40 0,0029- 0.017" Flour to Sugar Fines Passing <0.0029" Flour and smaller #200 Materials Testing & Consulting, Inc. Exploration Log Key FIGURE 777 Chrysler Drive Proposed Residence Burlington, WA 98233 1211 6 Street 3 Anacortes, WA 98221 30 uber Residence Geotechnical Report Materials Testing & Consulting, Inc. January 10, 2019 Project No.: 18B355 Matertials Testing & Consulting Log of Test Pit TP-1 Burlington, WA Geotechnical and Environmental Engineering Huber Residence Geotech Date Started : 12/14/18 1211 6th Street Date Completed : 12/14/18 Anacortes, WA 98221 Sampling Method : Grab Samples Location : NW Lot Corner: See Map MTC Job# 18B355 Logged By : Kevin Quillen 0 0 N 4) (I) C a DESCRIPTION E 0 TOPSOIL; SILTY SAND, loose, damp, abundant roots. Dark BROWN. - OL-SM I' TOPSOIL SILTY SAND, with clay, medium dense, damp to moist, faint to moderate oxidation throughout, roots in upper horizon, fine-grained sand. Light BROWN with - ' some ORANGE-BROWN staining. 2_ Fine-Grained Subsoils - SM \-Pockets of organic-rich silty sand w/some cobbles and trace charcoal. x_ f 'SILTY SAND to SANDY SILT, dense to hard, damp, trace oxidation staining, some thin interbeds of variable silt content, fine-grained sand, consolidated and breaks 4— into chunks. MEDIUM BROWN GLACIAL DRIFT _ SM-ML - i _ T.D. 6.0' BPG Terminated at planned depths. No groundwater encountered. 8- 10- 31 Huber Residence Geotechnical Report Materials Testing & Consulting, Inc, January 10, 2019 Project No.: 1813355 Matertials Testing & Consulting Log of Test Pit TP-2 Burlington, WA Geotechnical and Environmental Engineering Huber Residence Geotech Date Started : 12/14/18 1211 6th Street Date Completed : 12/14/18 Anacortes, WA 98221 Sampling Method : Grab Samples Location : NW House Corner: See Map MTC Job# 18B355 Logged By : Kevin Quillan 0 0 Q) _ C (0 Q) Li_ N C = J w to a- DESCRIPTION a1 Q- C ° iL 0) U E L c� o C� v) 0 _ l TOPSOIL; SILTY SAND WITH GRAVEL, loose, damp, gravel <6" rounded _ ' to angular, moderate roots, trash remains, charcoal. DARK BROWN. OL-SM TOPSOIL _ SAND, some silt and gravel (<6", subrounded), loose to medium dense, damp, variable deposits, one large -1' cobble, large charcoal seam. RED-BROWN to Medium BROWN. 2-- - HISTORIC FILL SW 1 I SILTY SAND, medium dense, dry to damp, faint oxidation throughout, small 4- pockets of oxidised and dense sands. Light BROWN. - Distinct tense with more oxidation. _ GLACIAL DRIFT 6- SM 8- 1. T.D. 9.5' BPG - Terminated at planned depths. 10- No groundwater encountered. 32 Huber Residence Ceoteehjiii al Report Materials Testing & Consulting, Inc. January 10, 2019 Project No.: 18B355 Matertials Testing & Consulting Log of Test Pit TP-3 Burlington, WA Geotechnical and Environmental Engineering Huber Residence Geotech Date Started : 12/14/18 1211 6th Street Date Completed : 12/14/18 Anacortes, WA 98221 Sampling Method : Grab Samples Location : Between Main House and Garage: See Map MTC Job # 18B355 Logged By : Kevin Quillen 0 0 N 4) C (B 4) U- U C = _1 Q) 4 DESCRIPTION Q U ("a o cn C� 5 cn a 0 TOPSOIL; SILTY SAND WITH GRAVEL, loose, damp, gravel <6" rounded to angular, abundant roots, trash remains. DARK BROWN. OL-SM TOPSOIL SANDY SILT to SILTY SAND, loose/soft, wet, abundant roots, trash remains, large cobbles (<1', subrounded). Medium BROWN. 2— HISTORIC FILL _ ML-SM 1' - I SANDY SILT to SILTY SAND, 30-60% fines, medium dense becoming dense with 4— depth, moderate mottling in upper 1.5', breaks into chunks. Light BROWN. Becomes dense (4.7'). GLACIAL DRIFT _ ML-SM 6— Difficult digging near base. X _ T.D. 7.0' BPG Terminated at planned depths. No groundwater encountered. 8- 10- 33 Huber Residence Geotechnical Report Materials Testing & Consulting, Inc. January 10, 2019 Project No.: 18B355 Matertials Testing & Consulting L® of Test Pit TP-4 Burlington, WA g Geotechnical and Environmental Engineering Huber Residence Geotech Date Started : 12/14/18 1211 6th Street Date Completed : 12/14/18 Anacortes, WA 98221 Sampling Method : Grab Samples Location : SE Lot Corner: See Map MTC Job# 18B355 Logged By : Kevin Quillen 0 0 N U) N C u- U _ 2 CO 0_ DESCRIPTION E L s o 0c o 0 0 TOPSOIL; SANDY SILT WITH GRAVEL, soft, damp, ' gravel <1.5" subrounded, abundant roots, trash remains, coarse grained sand. DARK BROWN. - OL-ML TOPSOIL _ l GRAVEL WITH SILT AND SAND, medium dense, damp to wet, reddish staining - pthroughout, moderate organics, coarse-grained sand, gravel <4" subrounded. REDDISH-BROWN. 2— ' GW-GM Coarse-Grained Subsoils ,'SANDY SILT to SILTY SAND, 45-55% fines, dense, damp, trace oxidation staining, consolidated and breakes in to chunks. Light BROWN with ORANGE-BROWN staining. 4— - SM-ML GLACIAL DRIFT I. 6— T.D. 5.8' BPG Terminated at planned depths. No groundwater encountered. 8- 10- 34 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 WILDCAT DYNAMIC CONE LOG Page 1 of 1 Materials Testing and Consulting 805 Dupont,Suite 5 PROJECT NUMBER: 18B355 Bellingham,WA 98225 DATE STARTED: 12-14-2018 DA 1'r.COMPLETED: 12-14-2018 HOLE#: DCP-1 CREW: Kevin Quillan SURFACE ELEVATION: PG PROJECT: Huber Residence Geotech WATER ON COMPLETION: NA ADDRESS: 1211 6th Street,Anacortes,Washington HAMMER WEIGHT: 35 lbs. LOCATION: NE House Comer:See Map CONE AREA: 10 sq.cm BLOWS RESISTANCE GRAPH OF CONE RESISTANCE TESTED CONSISTENCY DEPTH PER 10 cm Kg/cm2 0 50 100 150 N SAND&SILT CLAY - 1 4.4 1 VERYLOOSE VERY SOFT I - 4 17.8 °°°•• 5 LOOSE MEDIUM STIFF - 1 ft 4 17.8 °°°°° 5 LOOSE MEDIUM STIFF - 3 13.3 °°° 3 VERYLOOSE SOFT - 3 13.3 °°° 3 VERYLOOSE SOFT - 2 ft 4 17.8 °°°°° 5 LOOSE MEDIUM STIFF - 6 26.6 •°°°°°° 7 LOOSE MEDIUM STIFF - 8 35.5 °°°°°°°°°° 10 LOOSE STIFF - 3 ft 10 44.4 °°°°°°°°°°°° 12 MEDIUM DENSE STIFF - 1 m 7 31.1 °°°°°°°°° 8 LOOSE MEDIUM STIFF - 7 27.0 ••••°°° 7 LOOSE MEDIUM STIFF - 4 ft 8 30.9 .....•0° 8 LOOSE MEDIUM STIFF - 20 77.2 •••••°°°°°°°°°°°°°°°°° 22 MEDIUM DENSE VERY STIFF - 50 193.0 •••••°°°°°°°°°°°©°°°°°°°°°°°°°°°°°°°°°°°°°°®®® VERYDINSE HARD - 5ft - 6ft - 2 m - '7 ft - 8 f1 - 9ft - 3m loft - llft - 12it - 4m 13ft 35 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 WILDCAT DYNAMIC CONE LOG Page 1 of 1 Materials Testing and Consulting 805 Dupont,Suite 5 PROJECT NUMBER: 18B355 Bellingham,WA 98225 DATE STARTED: 12-14-2018 DATE COMPLETED: 12-14-2018 HOLE#: DCP-2 CREW: Kevin Quillan SURFACE El FVATION: PG PROJECT: Huber Residence Geotech WATER ON COMPLETION: NA ADDRESS: 1211 6th Street,Anacortes,Washington HAMMER WEIGHT: 35 lbs. LOCATION: SE House Corner:See Map CONE AREA: 10 sq.cm BLOWS RESISTANCE GRAPH OF CONE RESISTANCE TESTED CONSISTENCY DEPTH PER 10 cm Kg/cm2 0 50 100 150 N' SAND&SILT CLAY 2 8.9 •• 2 VERY LOOSE SOFT - 2 8.9 •• 2 VERY LOOSE SOFT - 1 ft 3 13.3 ••• 3 VERY LOOSE SOFT 5 22.2 6 LOOSE MEDIUM STIFF - 7 31.1 8 LOOSE MEDIUM STIFF - 2 ft 9 40.0 11 MEDIUM DENSE STIFF - 12 53.3 15 MEDIUM DENSE STIFF 18 79.9 22 MEDIUM DENSE VERY STIFF - 3 ft 16 71.0 20 MEDIUM DENSE VERY STIFF - 1 m 10 44.4 12 MEDIUM DENSE STIFF 21 81.1 23 MEDIUM DENSE VERY STIFF - 4 ft 18 69.5 19 MEDIUM DENSE VERY STIFF - 12 46.3 13 MEDIUM DENSE STIFF - 15 57.9 16 MEDIUM DENSE VERY STIFF - 5 ft 20 77.2 22 MEDIUM DENSE VERY STIFF - 27 104.2 - MEDIUM DENSE VERY STIFF - 32 123.5 - DENSE HARD - 6 ft 50 193.0 - VERY DENSE HARD - 50 193.0 - VERY DENSE HARD - 2 m - 7ft - 8ft - 9ft - 3m loft - 11ft - 12ft - 4m 13ft 36 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 WILDCAT DYNAMIC CONE LOG Page 1 of 1 Materials Testing and Consulting 805 Dupont,Suite 5 PROJECT NUMBER: 18B355 Bellingham,WA 98225 DATE STARTED: 12-14-2018 DATE COMPLETED: 12-14-2018 HOLE#: DCP-3 CREW: Kevin Quillan SURFACE ELEVATION: PG PROJECT: Huber Residence Geotech WATER ON COMPLETION: NA ADDRESS: 1211 6th Street,Anacortes,Washington HAMMER WEIGHT: 35 lbs. LOCATION: South of Garage:See Map CONE AREA: 10 sq.cm BLOWS RESISTANCE GRAPH OF CONE RESISTANCE TESTED CONSISTENCY DEPTH PER 10 cm Kg/cm2 0 50 100 150 N' SAND&SILT CLAY - 0 0.0 0 VERY LOOSE VERY SOFT - 4 17.8 5 LOOSE MEDIUM STIFF - 1 ft 12 53.3 15 MEDIUM DENSE STIFF - 10 44.4 12 MEDIUM DENSE STIFF - 8 35.5 10 LOOSE STIFF - 2 ft 8 35.5 10 LOOSE STIFF - 6 26.6 7 LOOSE MEDIUM STIFF - 3 13.3 ••• 3 VERY LOOSE SOFT - 3 ft 3 13.3 ••• 3 VERY LOOSE SOFT - 1 m 7 31.1 8 LOOSE MEDIUM STIFF - 11 42.5 12 MEDIUM DENSE STIFF - 4 ft 32 123.5 - DENSE HARD - 36 139.0 - DENSE HARD - 37 142.8 - DENSE HARD 5 ft 50 193.0 - VERY DENSE HARD 6ft - 2 m 7ft 8ft 9ft - 3m 10ft - 11ft - 12ft - 4m 13ft 37 Huber Residence Geotechnical Report Materials Testing&Consulting,Inc. January 10,2019 Project No.: 18B355 Appendix D. LABORATORY RESULTS Laboratory tests were conducted on several representative soil samples to better identify the soil classification of the units encountered and to evaluate the material's general physical properties and engineering characteristics. A brief description of the tests performed for this study is provided below. The results of laboratory tests performed on specific samples are provided at the appropriate sample depths on the individual boring logs. However, it is important to note that these test results may not accurately represent in situ soil conditions. All of our recommendations are based on our interpretation of these test results and their use in guiding our engineering judgment. MTC cannot be responsible for the interpretation of these data by others. Soil samples for this project will be retained for a period of 30 days following completion of this report, unless we are otherwise directed in writing. SOIL CLASSIFICATION Soil samples were visually examined in the field by our geologist at the time they were obtained. They were subsequently packaged and returned to our laboratory where they were reexamined, and the original description checked and verified or modified. With the help of information obtained from the other classification tests, described below, the samples were described in general accordance with ASTM Standard D2487. The resulting descriptions are provided at the appropriate locations on the individual exploration logs, located in Appendix C, and are qualitative only. GRAIN-SIZE DISTRIBUTION Grain-size distribution analyses were conducted in general accordance with ASTM Standard D422 on representative soil samples to determine the grain-size distribution of the on-site soil. In addition, soil liquid and plastic limits and plasticity index were determined with ASTM Standard D4318 on representative fine-grained samples. The information gained from these analyses allows us to provide a description and classification of the in-place materials. In turn, this information helps us to understand engineering properties of the soil and thus how the in-place materials will react to conditions such as heavy seepage, traffic action, loading, potential liquefaction, and so forth. The results are presented in this Appendix. PLASTICITY INDEX Soil liquid and plastic limits and plasticity index were determined with ASTM Standard D4318 on representative fine-grained samples. Atterburg Limits results are employed in better understanding the site materials anticipated behavior in terms of its plasticity state, moisture sensitivity and compressibility. The limits results are also used to classify fine-grained soils per ASTM Standard D2487. In addition, the liquid limit test initially determines whether the soil is plastic or non-plastic, and therefore its eligibility for plasticity testing. 38 1 Huber Residence Geotechnical Report Materials Testing & Consulting, Inc. January 10, 2019 Project No.: 18B355 %Nag Materials Te Consulting , .t. i Geotechnical Engineering • Special Inspection • Materials Testing • Environmental Consulting rtr'!r'�`rr}t1a�bCnes•1. k'' OP Sieve Report Project: Huber Residence Redevelopment Date Received: 19-Dec-18 Visual Identification Project#: 18B355 Sampled By: K.Quillan -Sandy Silt with Clay CPk., Client: Michael Huber Date Tested: 24-Dec-18 Sample Color: Source: TP-1 @ 2.5' Tested By: A. Eifrig Brow 'ACCREDITED, r.['t•e. Y.t'fii 01.tii6D2a1=.65.{µ Sample#: B18-1117 ._ AASITFO T 176,AASIITO T 255,AASTHO T 335,AASHFO T 89,AASIITO T 90 - D(s)_ 0.007 nun % Gravel= 0.0% Coeff. of Curvature, Cc= 1.40 Specifications D(lol= 0.013 mm %Sand= 43.0% Coeff.of Uniformity,Cu= 6.45 No Specs D(15)- 0.020 mm % Silt&Clay = 57.0% Fineness Modulus= 0.34 Sample Meets Specs ? N/A D(30)= 0.039 mm Liquid Limit = n/a Plastic Limit= n/a D(50)= 0.066 nun Plasticity Index= n/a Moisture%,as sampled= 19.7% D(60)= 0.085 mm Sand Equivalent= n/a Req'd Sand Equivalent= D(9om= 0.305 nun Fracture%, I Face= n/a Req'd Fracture%, 1 Face=r Dust Ratio= 53/91 Fracture%,2+Faces= n/a Req'd Fracture%,2+Faces=r AASHTO T11/127 Actual (Interpolated Gran Size Distribution N _ Cumulative'Cumulative _ ______ 4� ^00000000vw Sieve Size ! Percent . Percent Specs Specs b m io y to 'o ,r i� N� '' N�'R•u,o m�...N US Metric I Passing 1 Passing Max Min _ "A IOD3a.• _ :•.'1111 ��•,_s��.!Ill11 t--r�• d frr,-t-r^-tr�rr�'r.-t---'- 100.Q�b iiii iiiii itl4'� ;II 1 fill 12.00" I 300.00 100% 100.0% 0.0% lMt 10.00" . 250.00 100% 100.0% 0.0% ",.. . i .11. 8.00" 1 200.00 ' 100% 100.0% 0.0% 901--1--=.ill1 i 1-L-i-- 1 -i--z__-Ilu�:. ,-.;_-_., i.u.-1--L.-"r[iLL-__ Sao% 1 `iiii i i Al ii 1 i in:: I.i ;lull i 1 ;iii i 1 6.00" I 150.00 1 100% 100.0% 0.0% 11 "" ! i Ili11 II111 i I I lull I 111111 4.00" 100.00 100% 100.0% 0.0% 11 1 i 1 �11 1 1 ! hill l ,* �!i!!1 1 .Ilil I I 3.00" ! 75.00 100% 100.0% 0.0% 80 .t" All 1 i�t--i--�i �ttt-1----;tltitt-t-1..111l-l--l�_-tttrtt-t i---- 'am ;;;; ,i11!1 ' ill::1 l ;!!;1 ' 1;1' ' 2.50" 1 63.00 100% 100.0% 0.0% ! ! i ! ;;;I :11111 I '(lull \'l'l hill 1 1111 1 2.00" 3 50.00 3 1 100% 100.0% 0.0% 7(%- ' s-i , .... 545.00 100% 100.0% o.o% :�1'�.u;`i `i'l"i�'1if t `'_i---ih 'r-iiltt 3-' itti'" _-"'_ 'a°� l o ;Ills ; ,II.l. 1 i.11 i 1I.1 .l. 1 ..! ... ,... i .1.50" 3 37.50 l0U% lUO.o% 0.0% • l"t •' 'l'I "• ! "'I • ' . 1l ,.. :.... ! 'l. I1 ..1.1 I 1.. . ■11. l I;il ; ;'1I' !';; • Ip . lull . 1.25" I 31.50 3 100% 100.0% 0.0% 6%--T 1i t l tr - Titt tit r --1lft i'ft+ trl--l--1ttt4+�1-T--- 'a' :.... . . till/u .1111 1 '.•.. -lull '• 100% 100% 100.0% 0.0% g �;11i 1 ! IIIII II 'hill 1 :Hill ;iii 1 ' Low 25.00 : 3/4" 1 19.00 I 100% 100% 100.0% 0.0% a _ ""i' t }_ __fI1111 _ _ ;1!!! ,11111 !'ill 1111 ! sob--t II1I 1 I Ill I t I- -' 1 I I 'l-- --h----i lI saCI% ,A 5/8" ! 16.00 100% 100.0% 0.0% I C 1 l ll 11 t Ctt t-- :lull , l/l u l u . .11 1 I , full . I ill .1111 . :ill. I 111 1 .1.1. . 1 .11 I 1/2" 12.50 I 100% 100% 100.0% 0.0% I =1111i l I II11 i I _�� i i 1li1 111. i .I 11 ,l 1 ..1 1100% 1 100% j 100.0% 0.0% �!1'I l ' ;l 11 !•!' : 111 ! ' •• • 3/8 9.50 i 1 4�--f---,!!!! '-i--- ftfi� T--iI 1-11--liittTl--�"fif -rii.---. 40.0% 1/4" i 6.30 1 100% I 100.U% 0.0% .• lu ul . . 1.1 . l . 1 l 1 1 1 1 ,IIIII •l111; I ! 1111' ' I ':1'II ! :Hill • I #4 1 4.75 I 100% 100% 100.0% 0.0% : Ili11 :Ili;; ; ; 11111 i l 'ilii! 1 ! ;1;I! 1 I 1 - #8 I 2.36 i 100% 100.0% 0.0% 37A` t- i1II 11-E--1--t111---1 11i I-�-}-t-- 11 4- t--llI -�-1- - 3a . , I 1 ! 11 i!li -- Hill l 1 I-- #10 i 2.00 l 100% 100% 100.0% 0.0% e 1;ii ! a;i;,flu' 'lit( !'ll' 111 ' ; ' ""' • ' :11111 III, i MI 1 #16 1 1.18 1 99% 3 100.0% 0.0% :'ff' ,-f-' -; tt -1-- i s•- _' " ...L_--Ill-i l l-t-' zan% soy--+--- i �" #20 1 0.850 1 I 98% 100.0% 0.0% liil I I . i Ili! I ii 1 1 111:1 I I mil .i I -- I ° o ° Hill, ; : :Ili!' 1 6ll: 1 ! :111,; . 1 111:l ; 1 #30 i 0.600 ; 98/0 100.0% 0.0/o :1.1m. 1 1 1.1 . lull. 1 .1 ,. . I ,11 1 1 I 'I111Ii l i IIIi ! ;IIIt i I ll!!I ; ; II ! ! I #40 0.425 I 98% 98% 100.0% 0.0% 10%--i---4444-1-+--a,14 4-1--i----Hft+'- -F-4---H MI-'--1----1144++'-a----- ino% #50 0.300 90% 100.0% 0.0% : ! :1II111 l I ,ill 11 l I I lilt l 1 1 I 'llll 11 I I HIM 1 1 I Inu. I . I :.lilt ! . 111 ' ! . 'lulu . . 1 lull; . 1 I #60 I 0.250 I 86% i 100.0% 0.0% • ! ;III; ; 1 I I! 'i i I ! fi�l��l'! ! I ! III!! I I I !;;!' 1 I 1 oSGt � + ^�� tl� �i'�Iv. LL1_�■1.,:■:i om:..... o.0% #80 I 0.180 1 82% 100.0% 0.0% lCo.oao la000 1.030 0.100 0.010 o.ao; #100 i 0.150 l 80% 80% 100.0% 0.0% #140 I 0.106 I 66% 100.0% 0.0% Porkta ste(mml #170 l 0.090 l 62% 100.0% 0.0% #200 I 0.075 I 57.0% I 57.0% 100.0% 0.0% 4- SeveSlHs --....v- Max Specs ®►.4nsrycs geveResu ds Copyright;Spears Engineering&Technical Services PS,;996-98 4 All results apply only to actual locations and materials tested. As a mutual protection to clients,the public and ourselves,all reports are submitted as the confidential property of clients,and authorization for publication ofstatemenls,conclusions or extracts from or regarding our reports is reserved pending our written approval. Comments: . . Reviewed by: Meehan Blodgett-Carrillo Materials Testing & Consulting, Inc. Lab Sample: TP-1 @ 2.5' FIGURE 777 Chrysler Drive Proposed Residence Burlington, WA 98233 1211 6th Street 4 Anacortes, WA 98221 39 Huber Residence Geotechnical Report Materials Testing & Consulting, Inc. January 10, 2019 Project No.: 18B355 4 MTC Materials e stirs onsu tin nc . : . .i.Geotechnical Engineering • Special Inspection • Materials Testing • Environmental Consulting ,''arna►,Te,l,ng kCtsr.oC1Ct` oP Sieve Report Project: Huber Residence Redevelopment Date Received: 19-Dec-18 Unified Soil Classification System,ASTM-2487 Project#: 18B355 Sampled By: K. Quillan GW-GM,Well-graded Gravel with Silt and Sand Cgki Client: Michael Huber Date Tested: 24-Dec-18 Sample Color: Source: TP-4 a 1.8' Tested By: A. Eifrig Brown (ACCREDITED, C;.:-0rate e.t:is:I.1145 a2 L t 1f5.N Sample#: B18-1118 AASHTO T 176,AASHTO T 255,AASTHO T 335,AASTHO T-89,AASHTO T 90 - D(5)= 0.044 mm %Gravel= 64.5% Coeff.of Curvature,Cc= 1.64 Specifications D(10)= 0.138 mm %Sand= 26.9% CoefT of Uniformity,Cu= 266.82 No Specs D(15)= 0.402 mm %Silt &Clay = 8.6% Fineness Modulus= 6.16 Sample Meets Specs ? N/A D(30)= 2.896 mm Liquid Limit = n/a Plastic Limit = n/a D(5ow= 24.592 mm Plasticity Index= n/a Moisture%,as sampled= 4.6% D(60)= 36.939 mm Sand Equivalent = n/a Req'd Sand Equivalent = D(90)= 66.479 mm Fracture%, 1 Face= n/a Rcq'd Fracture%, 1 Face= Dust Ratio= 0.556 Fracture%,2+Faces= n/a Req'd Fracture%,2+Faces=r AASTHO TI1/1.27 Actual Interpolated Gran Size Distribution _ Cumulative Cumulative Sieve Size Percent Percent Specs Specs 0000 bbz Qi7 _ _ ,,_ ,._ •o�0000mo,no US Metric Passing Passing 1 Max l Min - " - `" -� -;_--#--` 1 ao5s..........,.. 1 ao.o% 12.00" 300.00 100% 100.0% 0.0% I t i 1!frT'-"11T1T1'1- -"- :rr r , ;rr.r.r , r r r �.r. . . .r..r . r n 44 . r .. .rrr 1 i !1 ! i I lit Iii ! iiijlil 1 iiiiiii i ji'iiii i 10.00" 250.00 100% 100.0% 0.0% I 1 1 1 1 1 li '11l111 I I it'd:111 I 1 1 ' ' i 8.00" 200.00 100% 100.0% 0.0% 9Q5 -_1_-_ I / 1- .. l---I I i I .L .:111 � „cm r 11 r r r t Ilrr 1 r rr,.. r . . .,I.I : 111,1 r r r 6.00" 1 150.00 100% 100.0% 0.0% li ' 9 i"1 1 :11i'si ' " :I'i1' 1 i i lid I i i 4.00" 100.00 3 100% 100.0% 0.0% I1111. 1,11. 1 'Ill1i i I _ lii'i111i_ .I111i I II' 11 I _t -t---lift'f' t-t- tf tt -j•"i --°-tit i-i"-t---'•I� t-t-t" "- 8G� 3.00" 75.00 100% 100% 100.0% 0.0% i i t t ;;i t i l I I ;; I ' , 1 tl t t i 1 Ili 1 1 I lilt I I 1 I ;IIIII I I :1111; 1 I 1 11,111 I I I 2.50" 63.00 86% 1U0.0% 0.0% I Irr I I I 1 a1;I I t I ;HMI I I i !II!1 1 I r !II i 1 1 I 2.00" 50.00 71% 71% 100.0% 0.0% 7ac--' 't,. i - ii•i,-1-t--;...._"4if•'. ... ri-__ILl ----- 7nM .r 1 11 i�i lllij' I i i I1111ItI1i�11 ! lU 1 i 1.75 45.00 67% 100.0% 0.0% ' Iii1 ti 1 i11 I , r ! I1 ;till( 1 1 !!1 i t 1 1 ;Him fill I i i iii.11 1.50" j 37.50 60% 100.0% 0.0% I . I 11 1 ' 1 _- "' ' I I Il'l I t I I 11 III 11 1 { I r r+-�111�I .4--t---- i i i 1 I- , 14}} .} - 11-Ei ti_ 1- a-1-E--1•---- sno� 1.25" 1 31.50 56% 100.0% 0.0% - _ II ' i l ! i!t 1 t 1 1 ;�111 �I t iiii i 1 I'I I ' t 1.00" 25.00 1 50% 50% 100.0% 0.0% s :11111 ;1r.1 1 : 1 t iris, i n (III I l i I 'kill i I I i ;llijji �i i�ii's ' i i ijiil � 1 i iliiii j • i jiifi i j i 3/4" 19.00 1 46% 46% 100.0% 0.0% a I i. 1 s f l i; i t aI I i t I t R'11: . 1 I tLt jl l I ; scK-1-i}}{.{.i4 i•t--:iif -t f ttttt-i----•itini-t---ii1� f-i-t---- �� eR 5/8" 16.00 i 45% 100.0% 0.0% . r•;;i r , . "t._"tart r . . r :rrrr . . ; III I r : ..r r r • r .r , . r r.,, , :;1:: , . . r rr . , tti Ii 1#• II ' t I illlli { i .(III it I liar 1/2" 12.50 43% 43% 100.0% 0.0% 1 III I I I l t 4• .111 1 I 1i 111 t I 1 'Iin1 I I I iiii I II I 3/8" 9.50 42% 42% 100.0% 0.0% i nil ; i 1 •' t t I '11;I I I,-I,.; 1!11 ,Ir,_�__m i 1 1 1 1 4ac--T--^ttrTtT-TV-•• Y TT T----rrrrt l9 T r•T•-•- 40.0% 37% - 11111' ' i i ;na ? - .Ililj I iillitl i iiiali ' r I. 1 . tr . . i . I .rltr1 . . , r I .1/4" 6.30 100.0% 0.0% ,I 1 1 :IIIII 1 lit 11 I II II . I l (III { #4 4.75 I 35% 35% 100.0% 0.0% iiii I i 1l II I t 1111' t I .Ills i i 1 i ;lit I I 1 atc --+--^y.{r..�f•i-f--i•-- 1ii-t -- ittri•,-•'1---t#'i --f--- i41i-i-F-t #8 2.36 28% 100.0% 0.0% ' I •�- t y liiiti I I --_- � r, r I r . 1,11 . I i t l . r n#10 2.00 27% 27% 100.0% 0.0% NI( I I I ilil 1 I li l 1 I 1 :IllsI t 1 1'II1 ! ii 1r1 ; 11;;11 ! 1 ;i ; ; 1 1 #16 1.18 21% 100.0% 0.0% -- II!! i I i _;Ills 1 i 1 •'lilt I t 'tits { i i till; i i I 2cmtrr mtm-t-t-•-�r rrt-�---itt11rt-r---nttrrl"t-•-- �� 420 0.850 19% 100.0% 0.0% I -!11 I I r i I I 1 I 1 ' ' •1 I 1 i ; 1 I I Il 11 1 I #30 0.600 17% 100.0% 0.0% ' !Aim I 1 .�tii l l I I I IIt•I I ,IIIII! I I ill i 1 I 1 1 1 1 1 I. r l 1 .. I I r . .1 1 1 . . , ilIM t ; ;mill 1 I I;t;; ; •,1 ;;t1i1 i t III{( ( I i #40 0.425 15% 15% 100.0% 0.0% 1M-I--tttr[Efh iiii! I II I--_±f I-Nit...4 i i i I ilif t' i--- lam #50 0.300 13% 100.0% 0.0% 1;,;I . r i ;1i'i . :Iii,. ; ";;; . t . ; , i 'till 11 j -illl l II I 11111 II till i 'i 'IIII11 1 #60 0.250 12% 100.0% 0.0% #80 0.180 11% 100.0% 0.0% io0.o00 ia000 (.coo 0.100 0.010 o.ou #100 0.150 10% 10% 100.0% 0.0% #140 0.106 9% 100.0% 0.0% Porno Ste(mm) #170 0.090 9% 100.0% 0.0% #200 0.075 8.6% 8.6% 100.0% 0.0% 1- Steve Slurs ®u•,===,MoxSpccs ....=Mn Specs Sieve Pesu s Copyright Spears Engineering&Technical Services PS.1996-98 All results apply only to actual locations and materials tested. As a mutual protection to clients,the public and ourselves,all reports are submitted as the confidential property of clients,and authorization for publication of statements,conclusions or cstracts from or regarding our reports is reserved pending our written approval. Comments: Reviewed by: Megban Blodgett-Carrillo Materials Testing & Consulting, Inc. Lab Sample: TP-4 @ 1.8' FIGURE 777 Chrysler Drive Proposed Residence Burlington, WA 98233 1211 6th Street 5 Anacortes, WA 98221 40