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2006_Geotechnical_Report_1309695240ce%vel) V YI 10 G0� GEOTECHNICAL ENGINEERING INVESTIGATION PROPOSED SINGLE FAMILY RESIDENCE 812 CARY ROAD EDMONDS, WASHINGTON PROJECT NO.092-06119 JULY 14, 2006 Prepared for: MR. AND MRS. MIKE AND SABINA NORTON 812 CARY ROAD EDMONDS, WASHINGTON 98020 Prepared by: KRAZAN & ASSOCIATES, INC. GEOTECHNICAL ENGINEERING DIVISION 19501 144r" AVENUE NE, #F-300 WOODINVILLE, WASHINGTON 98072 (425) 485-5519 I<Xa an & ASSOCIATES, INC. SITE DEVELOPMENT ENGINEERS '�azan & ASSOCIATES,INC. GEOTECHNICAL ENGINEERING • ENVIRONMENTAL ENGINEERING CONSTRUCTION TESTING & INSPECTION July 5, 2006 Mike and Sabina Norton 806 Cary Road Edmonds, Washington 98020 RE: Geotechnical Engineering Investigation Report Proposed Single Family Residence 812 Cary Road Edmonds, Washington Dear Mr. and Mrs. Norton: KA Project No. 092-06119 In accordance with your request, we have completed a Geotechnical Engineering Investigation for the referenced site. The results of our investigation are presented in the attached report. If you have any questions or if we can be of further assistance, please do not hesitate to contact our office. Respectfully submitted, KRAZAN AND ASSOCIATES, INC. Ben Clawson Staff Geologist BBC/slc Eleven Offices Serving The Western United States 19501 144"' Ave. NE NF-300• Woodinville, Washington 98072 • (425) 485-5519 • Fax: (425) 485-6837 092-06119 doc = [�az an & ASSOCIATES,INC. GEOTECHNICAL ENGINEERING • ENVIRONMENTAL ENGINEERING CONSTRUCTION TESTING & INSPECTION TABLE OF CONTENTS INTRODUCTION............................................................................................................................................................... I PURPOSEAND SCOPE....................................................................................................................................................I PROPOSEDCONSTRUCTION.......................................................................................................................................2 SITELOCATION AND DESCRIPTION.........................................................................................................................2 GEOLOGICSETTING......................................................................................................................................................2 FIELDINVESTIGATION.................................................................................................................................................3 SOIL PROFILE AND SUBSURFACE CONDITIONS...................................................................................................3 GROUNDWATER..............................................................................................................................................................3 SEISMICCONDITIONS...................................................................................................................................................4 SoilLiquefaction..............................•--..............................................................................................................................4 CONCLUSIONSAND RECOMMENDATIONS............................................................................................................5 SitePreparation.................................................................................................................................................................5 Temporary Excavations ............................... .......................................................................6 .... ........... .... ................................ StructuralFill....................................................................................................................................................................7 Erosionand Sediment Control................................................................,.............. , _............................................................8 Groundwater Influence on Structures/Construction.....................................,.....................................................................8 Drainageand Landscaping........................................................................................................................ . ............9 UtilityTrench Backfill......................................................................................................................................................9 Floor Slabs and Exterior Flatwork.............................................................................._....................................................10 ShallowFoundations.......................................................................................................................................................10 Lateral Earth Pressures and Retaining Walls . ............ ................................... :..:....... ............................ .............................. I I Testingand Inspection....................................................................................................................................................12 LIMITATIONS.................................................................................................................................................................13 VICINITYMAP............................................................................................................................................Figure 1 SITEPLAN....................................................................................................................................................Figure 2 FIELD INVESTIGATION AND LABORATORY TESTING......................................................... Appendix A EARTHWORK SPECIFICATIONS.................................................................................................... Appendix B Eleven Offices Serving The Western United States 19501 144"' Ave. NE NF-300• Woodinville, Washington 98072 • (425) 485-5519 • Fax: (425) 485-6837 091-061 19 doc 1'(XaZall & ASSOCIATES,INC. GEOTECHNICAL ENGINEERING • ENVIRONMENTAL ENGINEERING CONSTRUCTION TESTING & INSPECTION July 14, 2006 KA Project No. 092-06119 GEOTECHNICAL ENGINEERING INVESTIGATION PROPOSED SINGLE FAMILY RESIDENCE 812 CARY ROAD EDMONDS, WASHINGTON INTRODUCTION This report presents the results of our Geotechnical Engineering Investigation for the proposed single family residence located at 812 Cary Road in Edmonds, Washington (See Figure 1 - Vicinity Map). Discussions regarding site conditions are presented herein, together with conclusions and recommendations pertaining to site preparation, excavations, structural fill, utility trench backfill, drainage and landscaping, erosion control, slope conditions, foundations, retaining/basement walls and concrete floor slabs and exterior flatwork. A site plan (Figure 2), showing the approximate exploratory test pit locations, is presented following the text of this report. A description of the field investigation and the laboratory testing program, the exploratory test pit logs and the results of the laboratory testing are presented in Appendix A. Appendix B contains guides to aid in the development of earthwork specifications. When conflicts in the text of the report occur with the general specifications in the appendix, the recommendations in the text of the report have precedence. PURPOSE AND SCOPE This investigation was conducted to evaluate the soil and groundwater conditions at the site, to develop geotechnical engineering recommendations for use in design of specific construction elements and to provide criteria for site preparation and structural fill construction. Our scope of services was performed in general accordance with our revised proposal for this project, dated June 8, 2006 (KA Proposal No. G06-126WAW) and included the following: • A site reconnaissance by a senior geologist to evaluate the surface conditions at the project site. ■ A field investigation consisting of excavating and sampling three exploratory test pits that generally cover the property to be developed. The exploratory test pits ranged in depth from approximately 4.5 to 5.5 feet below the existing site grades. Eleven Offices Serving The Western United States 19501 144th Ave. NE #F-300 • Woodinville, Washington 98072 • (425) 485-5519 • Fax: (425) 485-6837 092-06119� KA No. 092-06119 July 14, 2006 Page No. 2 of 14 + Performing laboratory tests on representative soil samples obtained from the exploratory test pits to evaluate the physical and index properties of the subsurface soils. + Evaluation of the data obtained from the investigation and completion of engineering analyses to develop recommendations for use in the project design and preparation of construction specifications. + Preparation of this report summarizing our findings, the results of our analyses and our conclusions and recommendations for this investigation. PROPOSED CONSTRUCTION We have not yet received specific information regarding the proposed residential structure. At this time, we anticipate that the proposed residence will consist of a one to two-story single family residence. We anticipate that the residential structure will be founded on shallow spread footings. Footing loads are expected to be light. We have not yet received a grading plan for the project. Preliminarily, we anticipate maximum cut and/or fill depths on the order of approximately 4 feet or less in order to be above the floodplain designation elevation and meet Federal Emergency Management Agency (FEMA) minimum requirements for finished floor grades. In the event that the structural or grading information detailed in this report is inconsistent with the final design, the geotechnical engineer should be notified so that we may update this writing as applicable. SITE LOCATION AND DESCRIPTION The site of the proposed single family residence is located at 812 Cary Road in Edmonds, Washington. The general location of the site is shown on the Vicinity Map (Figure 1). The site consists of an approximately 2.5 acre, partially developed lot. The majority of the site gently slopes downward to the east towards a designated wetland area on the eastern portion of the site. The site is bordered to the north and south by single family residences, to the west by Cary Road, and to the east by undeveloped property. GEOLOGIC SETTING The site lies within the central Puget Lowland. The lowland is part of a regional north -south trending trough that extends from southwestern British Columbia to near Eugene, Oregon. North of Olympia, Washington, this lowland is glacially carved, with a depositional and erosional history including at least four separate glacial advances/retreats. The Puget Lowland is bounded to the west by the Olympic Mountains, and to the east by the Cascade Range. The lowland is filled with glacial and nonglacial sediments consisting of interbedded gravel, sand, silt, till, and peat lenses. Krazan & Associates, Inc. Eleven Offices Serving The Western United States 09'-06119 doc KA No. 092-06119 July 14, 2006 Page No. 3 of 14 According to the United States Geological Survey (USGS) Geological Map of the Edmonds East Quadrangle, the property is underlain by the Whidbey Formation. The sediments typically consist of bedded, compact, commonly oxidized, medium to coarse grained sands and silty sands. FIELD INVESTIGATION A field investigation consisting of excavating and sampling three exploratory test pits, that provided general coverage of the property to be developed, was completed to evaluate the subsurface soil and groundwater conditions. The test pits ranged in depth from approximately 4.5 to 5.5 feet below the existing grades. The excavation work was performed on June 26, 2006 with a Bobcat 435ZHS Trackhoe supplied by the client. Representative samples of the subsurface soils encountered in the test pits were collected and sealed in plastic bags. These samples were transported to our laboratory for further examination and verification of the field classifications. The soils encountered in the test pits were continuously examined and visually classified in accordance with the Unified Soil Classification System (USCS). A more detailed description of the field investigation is presented in Appendix A. Laboratory tests were performed on selected soil samples to evaluate their physical characteristics and engineering properties. The laboratory testing program was formulated with an emphasis on the evaluation of natural moisture content and gradation of the materials encountered. Details of the laboratory testing program and results of the laboratory tests are summarized in Appendix A. This information, along with the field observations, was used to prepare the final exploratory test pit logs, which are presented in Appendix A. SOIL PROFILE AND SUBSURFACE CONDITIONS The soils encountered in the exploratory test pits were generally typical of those found in the described geologic units. Exploratory Test Pits TP-1 through TP-3 encountered loose, fine to medium grained silty sand (topsoil) extending approximately 0.5 to 1 feet below existing site grades. Underlying the topsoil layer was approximately 2 to 3.5 feet of loose, fine to coarse grained silty sand characterized as weathered Whidbey Formation. Beneath the loose silty sand, all three exploratory test pits encountered dense to very dense, fine to coarse grained sand with gravel interbedded with fine grained sand layers characterized as Whidbey Formation which extended down to the termination depths of the exploratory test pits. For additional information about the soils encountered, please refer to the logs of the exploratory test pits in Appendix A. GROUNDWATER The exploratory test pits were checked for the presence of groundwater during and immediately following the excavation operations. Groundwater was not encountered in the exploratory test pits at the date and time of our field investigation. It should be recognized that water table elevations may fluctuate with time. The groundwater level will be dependent upon seasonal precipitation, irrigation, land use, and climatic conditions, as well as other factors. Therefore, water levels at the time of the field investigation may be different from those Krazan & Associates, Inc. Eleven Offices Serving The Western United States 09 -06119 doc KA No. 092-06119 July 14, 2006 Page No. 4 of 14 encountered during the construction phase of the project. The evaluation of such factors is beyond the scope of this report. Groundwater flow may become heavier during construction activities which take place during the wet weather season. This may cause difficulties with the grading and excavation work. Certain remedial and/or de -watering measures may be required. SEISMIC CONDITIONS The glacial soils encountered in the exploratory test pits, primarily below a depth of about 2 feet, were generally medium dense to very dense. The overall soil profile generally corresponds to a site class soil profile of D as defined by Table 1615.1.1 of the 2003 International Building Code (IBC). A site class soil profile of D applies to a profile consisting primarily of medium dense to dense or stiff soils within the upper 100 feet. Sail Liquefaction Soil liquefaction is a state where soil particles lose contact with each other and become suspended in a viscous fluid. This suspension of the soil grains results in a complete loss of strength as the effective stress drops to zero. Liquefaction normally occurs under saturated conditions in soils such as sand in which the strength is purely frictional. However, liquefaction has occurred in soils other than clean sand. Liquefaction usually occurs under vibratory conditions such as those induced by seismic events. To evaluate the liquefaction potential of the site, we analyzed the following factors: 1) Soil type 2) Groundwater depth 3) Relative soil density 4) Initial confining pressure 5) Maximum anticipated intensity and duration of ground shaking The relatively shallow subsurface soils encountered at this site are comprised of medium dense, variable mixtures of silt, sand and gravel. Due to the relatively dense nature of the majority of the on site soils, it is our opinion that the liquefaction potential at this site is low. It is our opinion that measures to mitigate liquefaction potential will not be required. Krazan & Associates, Inc. Eleven Offices Serving The Western United States KA No. 092-06119 July 14, 2006 Page No. 5 of 14 CONCLUSIONS AND RECOMMENDATIONS General Based on the findings of this investigation, it is our opinion that the proposed single family residence may be supported on a shallow spread footing foundation system. The spread footings may be founded on the medium dense to very dense native soil, or on compacted structural fill placed on the medium dense to very dense native soils. The bearing soils for shallow foundation support were encountered in the exploratory test pits at depths ranging from approximately 2.5 to 4 feet below the existing ground surface. If loose native soils and/or undocumented fill are encountered at footing grades, recommendations for overexcavation and/or re -compaction will be provided at the time of the site inspection work. Site Prenarattion Site clearing should be limited to the areas necessary for construction of the single family home and associated driveways and structures. Clearing should include removal of vegetation; trees and associated root systems; wood; existing utilities; structures including foundations, basement walls and floors; rubble; and rubbish. Site stripping should extend to a minimum depth of 6 to 12 inches (preliminary; based on our test pit locations), or until all organics in excess of 3 percent by volume are removed. These materials will not be suitable for use as structural fill. However, stripped topsoil may be stockpiled and reused in landscape or non-structural areas. After stripping operations and removal of any undocumented fill, the building pad areas should be visually inspected to identify any loose areas. Any remaining loose soils should be overexcavated to the level of the medium dense to very dense native soils. The resulting excavations should be filled with approved on site material, or imported structural fill. Structural fill material should be within ± 2 percent of the optimum moisture content, and the soils should be compacted to a minimum of 95 percent of the maximum dry density based on ASTM Test Method D1557. During wet weather conditions, typically October through May, subgrade stability problems and grading difficulties may develop due to excess moisture, disturbance of sensitive soils and/or the presence of perched groundwater. Construction during the extended wet weather periods could create the need to overexcavate exposed soils if they become disturbed and cannot be recompacted due to elevated moisture contents. The on site native soils have variable silt and clay contents and are considered moisture sensitive and easily disturbed. If overexcavation is necessary, it should be confirmed through continuous monitoring and testing by a qualified geotechnical engineer or senior geologist. Soils that have become unstable may require drying and recompaction. Selective drying may be accomplished by scarifying or windrowing surficial material during extended periods of dry, warm weather (typically during the summer months). If the soils cannot be dried back to a workable moisture condition, remedial measures may be required. General project site winterization should consist of the placement of aggregate base and the protection of exposed soils during the construction phase. It should be understood that even if Best Management Practices (BMP's) for wintertime soil protection are Krazan & Associates, Inc. Eleven Offices Serving The Western United States 091-06119.doc KA No. 092-06119 July 14, 2006 Page No. 6 of 14 implemented and followed, there is a significant chance that moisture disturbed soil mitigation work will still be required. Any buried structures encountered during construction should be properly removed and backfilled. Excavations, depressions, or soft and pliant areas extending below the planned finish subgrade levels should be cleaned to firm undisturbed soil, and backfilled with structural fill. In general, any septic tanks, underground storage tanks, debris pits, cesspools, or similar structures should be completely removed. Concrete footings should be removed to an equivalent depth of at least 3 feet below proposed footing elevations or as recommended by the geotechnical engineer. The resulting excavations should be backfilled with structural fill. A representative of our firm should be present during all site clearing and grading operations to test and observe earthwork construction. This testing and observation is an integral part of our service, as acceptance of earthwork construction is dependent upon compaction and stability of the material. The geotechnical engineer may reject any material that does not meet compaction and stability requirements. Further recommendations, contained in this report, are predicated upon the assumption that earthwork construction will conform to the recommendations set forth in this section and in the Structural Fill Section. Temoorary Excavations The on site native soils have variable cohesion strengths, therefore the safe angles to which these materials may be cut for temporary excavations is limited, as the soils may be prone to caving and slope failures in temporary excavations deeper than 4 feet. Temporary excavations in the medium dense to dense native soils should be sloped no steeper than 1H:1V (horizontal to vertical) where room permits. Temporary excavations in very dense native soils, if encountered at greater depths, should be sloped no steeper than 3/41-1:1 V (horizontal to vertical) where room permits. If the soil in the excavation is subject to vibration from heavy traffic, the temporary excavation should be sloped no steeper than 1'/2H:1 V (horizontal to vertical). All temporary cuts should be in accordance with Washington Administrative Code (WAC) Part N, Excavation, Trenching, and Shoring. The temporary slope cuts should be visually inspected daily by a qualified person during construction work activities and the results of the inspections should be included in daily reports. The contractor is responsible for maintaining the stability of the temporary cut slopes and minimizing slope erosion during construction. The temporary cut slopes should be covered with visqueen to help minimize erosion during wet weather and the slopes should be closely monitored until the permanent retaining systems are complete. Materials should not be stored and equipment operated within 10 feet of the top of any temporary cut slope. A Krazan & Associates geologist or geotechnical engineer should observe, at least periodically, the temporary cut slopes during the excavation work. The reasoning for this is that all soil conditions may not be fully delineated during the previous geotechnical exploratory work. In the case of temporary slope cuts, the existing soil conditions may not be fully revealed until the excavation work exposes the soil. Typically, as excavation work progresses the maximum inclination of the temporary slope will need to be reevaluated by the geotechnical engineer so that supplemental recommendations can be made. Soil and groundwater conditions can be highly variable. Scheduling for soil work will need to be Krazan & Associates, Inc. Eleven Offices Serving The Western United States 091_-06119.duc KA No. 092-06119 July 14, 2006 Page No. 7 of 14 adjustable, to deal with unanticipated conditions, so that the project can proceed smoothly and required deadlines can be met. If any variations or undesirable conditions are encountered during construction, Krazan & Associates should be notified so that supplemental recommendations can be made. Structural Fill Best Management Practices (BMP's) should be followed when considering the suitability of native material for use as structural fill. Native soils can have elevated natural moisture contents, and may need to be dried back during dry, warm weather (typically during summer months). Native soils with variable fines (silt and clay) contents will be moisture sensitive. The native soils are generally considered suitable for reuse as structural fill, provided the soil is relatively free of organic material and debris, and it is within f 2 percent of the optimum moisture content. If the native soils are stockpiled for later use as structural fill, the stockpiles should be covered to protect the soil from wet weather conditions. We recommend that a representative of Krazan & Associates be on site during the excavation work to determine which soils are suitable for structural fill. It should not be taken for granted that the onsite soils may be used as the sole source for structural fill (especially during winter construction activities). During wet weather conditions the soils with higher silt and clay contents will be moisture sensitive, easily disturbed and most likely will not meet compaction requirements. Furthermore, during the winter the native soils typically have elevated natural moisture contents, which will limit the use of these materials as structural fill without proper mitigation measures. The contractor should use Best Management Practices to protect the soils during construction activities and be familiar with wet weather and wintertime soil work. An allowance for importing structural fill should be incorporated into the construction cost of the project (for wintertime construction this may be as high as 100 percent import). Imported structural fill material should consist of well -graded gravel or a sand and gravel mixture with a maximum grain size of 1'/z inches and less than 5 percent fines (material passing the U.S. Standard No. 200 Sieve). All structural fill material should be submitted for approval to the geotechnical engineer at least 48 hours prior to delivery to the site. Fill soils should be placed in horizontal lifts not exceeding 8 inches loose thickness, moisture - conditioned as necessary, (moisture content of soil shall not vary by more than f2 percent of optimum moisture) and the material should be compacted to at least 95 percent of the maximum dry density based on ASTM Test Method D1557. In place density tests should be performed on all structural fill to verify proper moisture content and adequate compaction. Additional lifts should not be placed if the previous lift did not meet the compaction requirements or if soil conditions are not considered stable. Krazan & Associates, Inc. Eleven Offices Serving The Western United States 093-06119.doc KA No. 092-06119 July 14, 2006 Page No. 8 of 14 Erosion and Sediment Control Erosion and sediment control (ESC) is used to minimize the transportation of sediment to wetlands, streams, lakes, drainage systems, and adjacent properties. Erosion and sediment control measures should be taken and these measures should be in general accordance with local regulations. As a minimum, the following basic recommendations should be incorporated into the design of the erosion and sediment control features of the site: 1) Phase the soil, foundation, utility and other work, requiring excavation or the disturbance of the site soils, to take place during the dry season (generally May through September). However, provided precautions are taken using Best Management Practices (BMP's), grading activities can be undertaken during the wet season (generally October through April), but it should also be known that this may increase the overall cost of the project. 2) All site work should be completed and stabilized as quickly as possible. 3) Additional perimeter erosion and sediment control features may be required to reduce the possibility of sediment entering surface water. This may include additional silt fences, silt fences with a higher Apparent Opening Size (AOS), construction of a berm, or other filtration systems. 4) Any runoff generated by dewatering discharge should be treated through construction of a sediment trap if there is sufficient space. If space is limited other filtration methods will need to be incorporated. Groundwater Influence on Structures/Construction Groundwater was not encountered in the exploratory test pits at the date and time of our field investigation. If groundwater is encountered during construction, it is most likely perched groundwater. Perched groundwater develops where vertical infiltration of surface precipitation is impeded by a relatively impermeable soil layer, resulting in horizontal migration of the groundwater within overlying more permeable soils. If groundwater is encountered during construction, we should observe the conditions to determine if dewatering will be needed. Design of temporary dewatering systems to remove groundwater should be the responsibility of the contractor. If earthwork is performed during or soon after periods of precipitation, the subgrade soils may become saturated. These soils may "pump," and the materials may not respond to densification techniques. Typical remedial measures include: discing and aerating the soil during dry, warm weather; mixing the soil with drier materials; and removing and replacing the soil with an approved fill material. A qualified geotechnical engineering firm should be consulted prior to implementing remedial measures to observe the unstable subgrade conditions and provide appropriate recommendations. Krazan & Associates, Inc. Eleven Offices Serving The Western United States 091-061 19.d- KA No. 092-06119 July 14, 2006 Page No. 9 of 14 Drainage and Landscaping The ground surface should slope away from building pads and pavement areas, toward appropriate drop inlets or other surface drainage devices. It is recommended that adjacent exterior grades be sloped a minimum of 2 percent for a minimum distance of 5 feet away from structures. Roof drains should be tightlined away from foundations and slope surfaces. Roof drains should not be connected to the footing drains, but may use the same outfall piping if connected well away from the structure such that roof water will not backup into the footing drains. Subgrade soils in pavement areas should be sloped a minimum of 1 percent and drainage gradients should be maintained to carry all surface water to collection facilities, away from slope surfaces. These grades should be maintained for the life of the project. The collection facilities should be tightlined away from slope areas, and disposed of where down slope properties, structures and slopes are not jeopardized. Specific recommendations for and design of storm water disposal systems or septic disposal systems are beyond the scope of our services and should be prepared by other consultants that are familiar with design and discharge requirements. Infiltration systems should not be located on slopes that exceed 30 percent nor should systems be "stacked" or lined up with one another down the slope. Infiltration systems should not be located up slope of residences or retaining structures. iltility Trench Backfill Utility trenches should be excavated according to accepted engineering practices following OSHA (Occupational Safety and Health Administration) standards, by a contractor experienced in such work. The responsibility for the safety of open trenches should be borne by the contractor. Traffic and vibration adjacent to trench walls should be minimized; cyclic wetting and drying of excavation side slopes should be avoided. Depending upon the location and depth of some utility trenches, groundwater flow into open excavations could be experienced, especially during or shortly following periods of precipitation. Sandy soil conditions were encountered at shallow depths in the exploratory test pits at the site. These soils generally have low to moderate cohesion and have a tendency to cave in trench wall excavations. Shoring or sloping back trench sidewalls may be required within these soils. All utility trench backfill should consist of imported structural fill or suitable on -site material. Utility trench backfill placed in or adjacent to buildings and exterior slabs should be compacted to at least 95 percent of the maximum dry density based on ASTM Test Method D1557. The upper 5 feet of utility trench backfill placed in pavement areas should be compacted to at least 95 percent of the maximum dry density based on ASTM Test Method D1557. Below 5 feet, utility trench backfill in pavement areas should be compacted to at least 90 percent of the maximum dry density based on ASTM Test Method D1557. Pipe bedding should be in accordance with the pipe manufacturer's recommendations. The contractor is responsible for removing all water -sensitive soils from the trenches regardless of the backfill location and compaction requirements. The contractor should use appropriate equipment and methods to avoid damage to the utilities and/or structures during fill placement and compaction. Krazan & Associates, Inc. Eleven Offices Serving The Western United States 092-06119.doc KA No. 092-06119 July 14, 2006 Page No. 10 of 14 Floor Slabs and Exterior Flatwork If slab -on -grade structures are proposed, in any structure areas where it is desired to reduce floor dampness, such as areas covered with moisture sensitive floor coverings, we recommend that the concrete slab -on -grade floors be underlain by a water vapor retarder system. The water vapor retarder system should be installed in accordance with ASTM Specification E164-94 and Standard Specifications E1745-97. According to ASTM Guidelines, the water vapor retarder should consist of a vapor retarder sheeting underlain by a minimum of 4-inches of compacted clean (less than 5 percent passing the U.S. Standard No. 200 Sieve), open -graded coarse rock of 3/4-inch maximum size. The vapor retarder sheeting should be protected from puncture damage. The exterior floors should be placed separately in order to act independently of the walls and foundation system. All fills required to bring the building pads to grade should be structural fill. It is recommended that the utility trenches within the structures be compacted, as specified in our report, to minimize the transmission of moisture through the utility trench backfill. Special attention to the immediate drainage and irrigation around the building is recommended. Positive drainage should be established away from the structure and should be maintained throughout the life of the structure. Ponding of water should not be allowed adjacent to the structure. Over -irrigation within landscaped areas adjacent to the structure should not be performed. In addition, ventilation of the structure (i.e. ventilation fans) is recommended to reduce the accumulation of interior moisture. Shallow Foundations The proposed residential structure may be supported on a shallow foundation system bearing on the medium dense to very dense native soils, or on properly compacted structural fill, placed on suitable native soils. Continuous wall or column footings may be designed for a net allowable bearing pressure of 2,000 pounds per square foot (psf) dead plus live load, if the footings bear directly on medium dense to very dense native soils on properly compacted structural fill above the suitable native soils. A 1/3 increase in the above value may be used for short duration, wind and seismic loads. Structural fill placed on bearing, native subgrade should be compacted to at least 95 percent of the maximum dry density based on ASTM Test Method D1557. Footing excavations should be inspected to verify that the foundations will bear on suitable material. Exterior footings should have a minimum depth of 18 inches below pad subgrade (soil grade) or adjacent exterior grade, whichever is lower. Interior footings should have a minimum depth of 12 inches below pad subgrade (soil grade) or adjacent exterior grade, whichever is lower. Footings should have a minimum width of 12 inches regardless of load. If constructed as recommended, the total settlement is not expected to exceed 1 inch. Differential settlement, along a 20-foot exterior wall footing, or between adjoining column footings, should be less than `/z inch, producing an angular distortion of 0.002. Most settlement is expected to occur during construction, as the loads are applied. However, additional post -construction settlement may occur if Krazan & Associates, Inc. Eleven Offices Serving The Western United States 092-00119.doc KA No. 092-06119 July 14, 2006 Page No. 11 of 14 the foundation soils are flooded or saturated or if a strong seismic event results in liquefaction of the underlying soils. It should be noted that the risk of liquefaction is considered low, given the composition and density of the native, on site soils. Seasonal rainfall, water run-off, and the normal practice of watering trees and landscaping areas around the proposed structures, should not be permitted to flood and/or saturate footings. To prevent the buildup of water within the footing areas, continuous footing drains (with cleanouts) should be provided at the bases of the footings. The footing drains should consist of a minimum 4-inch diameter perforated pipe, sloped to drain, with perforations placed down and enveloped by 1-inch sized washed rock in all directions and filter fabric to prevent the migration of fines. Resistance to lateral footing displacement can be computed using an allowable friction factor of 0.30 acting between the bases of foundations and the supporting subgrade. Lateral resistance for footings can alternatively be developed using an allowable equivalent fluid passive pressure of 270 pounds per cubic foot (pcf) acting against the appropriate vertical footing faces. The allowable friction factor and allowable equivalent fluid passive pressure values include a factor of safety of 1.5. The frictional and passive resistance of the soil may be combined without reduction in determining the total lateral resistance. A 1/3 increase in the above values may be used for short duration, wind and seismic loads. Lateral Earth Pressures and Retaininn Walls We have developed criteria for the design of retaining or below grade walls, in case this information is required. Our design parameters are based on retention of the in place soils. The parameters are also based on a level backfill condition. Walls may be designed as "restrained" retaining walls based on "at - rest" earth pressures, plus any surcharge on top of the walls as described below, if the walls are attached to the buildings and/or movement is not acceptable. Unrestrained walls may be designed based on "active" earth pressure, if the walls are not part of the buildings and some movement of the retaining walls is acceptable. Acceptable lateral movement equal to at least 0.2 percent of the wall height would warrant the use of "active" earth pressure values for design. The following table, titled Wall Design Criteria, presents the recommended soil related design parameters for retaining walls with level backfill. Contact Krazan & Associates, Inc. if an alternate retaining wall system is used. Krazan & Associates, Inc. Eleven Offices Serving The Western United States 092-06119.doe KA No. 092-06119 July 14, 2006 Page No. 12 of 14 "At -rest" Conditions Wall Design Criteria 55 psf/foot of depth "Active" Conditions 135 psf/foot of depth Passive Earth Pressure on Low Side of Wall Neglect upper 2 feet, then 270 psf/linear foot (Allowable, includes F.S. = 1.5) of depth. Soil -Footing Coefficient of Sliding Friction 0.30 (Allowable; includes F.S. = 1.5) The stated lateral earth pressures do not include the effects of hydrostatic pressure (from water accumulation), seismic loads or loads imposed by construction equipment, roadways or foundations (surcharge loads). To minimize the lateral earth pressure and prevent the buildup of water pressure against the walls, continuous footing drains (with cleanouts) should be provided at the bases of the walls. The footing drains should consist of a minimum 4-inch diameter perforated pipe, sloped to drain, with perforations placed down and enveloped by 6 inches of pea gravel in all directions and filter fabric to prevent the migration of fines. The backfill adjacent to and extending a lateral distance behind the walls of at least 2 feet should consist of free -draining granular material. All free draining backfill should contain less than 3 percent fines (passing the U.S. Standard No. 200 Sieve) based upon the fraction passing the U.S. Standard No. 4 Sieve with at least 30 percent of the material being retained on the U.S. Standard No. 4 Sieve. It should be realized that the primary purpose of the free -draining material is the reduction of hydrostatic pressure. Some potential for the moisture to contact the back face of the wall may exist, even with treatment, which may require that more extensive waterproofing be specified for walls that require interior moisture sensitive finishes. We recommend that the backfill be compacted to at least 90 percent of the maximum dry density based on ASTM Test Method D1557. In -place density tests should be performed to verify adequate compaction. Soil compactors place transient surcharges on the backfill. Consequently, only light, hand - operated equipment is recommended within 3 feet of walls so that excessive stress is not imposed on the walls. Testing and Inspection A representative of Krazan & Associates, Inc. should be present at the site during the earthwork activities to confirm that actual subsurface conditions are consistent with the exploratory fieldwork. This activity is an integral part of our services, as acceptance of earthwork construction is dependent upon compaction testing and stability of the material. This representative can also verify that the intent of these recommendations is incorporated into the project design and construction. Krazan & Associates, Inc. will not be responsible for grades or staking, since this is the responsibility of the Prime Contractor. Furthermore, Krazan & Associates is not responsible for the contractor's procedures, methods, scheduling or management of the work site. Krazan & Associates, Inc. Eleven Offices Serving The Western United States 092-06119.doc KA No. 092-06119 July 14, 2006 Page No. 13 of 14 LIMITATIONS Geotechnical engineering is one of the newest divisions of Civil Engineering. This branch of Civil Engineering is constantly improving as new technologies and understanding of earth sciences improves. Although your site was analyzed using the most appropriate current techniques and methods, undoubtedly there will be substantial future improvements in this branch of engineering. In addition to improvements in the field of geotechnical engineering, physical changes in the site either due to excavation or fill placement, new agency regulations or possible changes in the proposed structure after the time of completion of the soils report may require the soils report to be professionally reviewed. In light of this, the owner should be aware that there is a practical limit to the usefulness of this report without critical review. Although the time limit for this review is strictly arbitrary, it is suggested that two years be considered a reasonable time for the usefulness of this report. Foundation and earthwork construction is characterized by the presence of a calculated risk that soil and groundwater conditions have been fully revealed by the original foundation investigation. This risk is derived from the practical necessity of basing interpretations and design conclusions on limited sampling of the earth. Our report, design conclusions and interpretations should not be construed as a warranty of the subsurface conditions. Actual subsurface conditions may differ, sometimes significantly, from those indicated in this report. The recommendations made in this report are based on the assumption that soil conditions do not vary significantly from those disclosed during our field investigation. The findings and conclusions of this report can be affected by the passage of time, such as seasonal weather conditions, manmade influences, such as construction on or adjacent to the site, natural events such as earthquakes, slope instability, flooding, or groundwater fluctuations. If any variations or undesirable conditions are encountered during construction, the geotechnical engineer should be notified so that supplemental recommendations can be made. The conclusions of this report are based on the information provided regarding the proposed construction. If the proposed construction is relocated or redesigned, the conclusions in this report may not be valid. The geotechnical engineer should be notified of any changes so that the recommendations can be reviewed and reevaluated. Misinterpretations of this report by other design team members can result in project delays and cost overruns. These risks can be reduced by having Krazan & Associates, Inc. involved with the design teams meetings and discussions after submitting the report. Krazan & Associates, Inc. should also be retained for reviewing pertinent elements of the design team's plans and specifications. Contractors can also misinterpret this report. To reduce this, risk Krazan & Associates. Inc. should participate in pre -bid and preconstruction meetings, and provide construction observations during the site work. This report is a geotechnical engineering investigation with the purpose of evaluating the soil conditions in terms of foundation design. The scope of our services did not include any environmental site assessment for the presence or absence of hazardous and/or toxic materials in the soil, groundwater or atmosphere, or the presence of wetlands. Any statements or absence of statements, in this report or on any test pit log regarding odors, unusual or suspicious items, or conditions observed are strictly for Krazan & Associates, Inc. Eleven Offices Serving The Western United States 092-06119 doc KA No. 092-06119 July 14, 2006 Page No. 14 of 14 descriptive purposes and are not intended to convey engineering judgment regarding potential hazardous and/or toxic assessments. The geotechnical information presented herein is based upon professional interpretation utilizing standard engineering practices and a degree of conservatism deemed proper for this project. It is not warranted that such information and interpretation cannot be superseded by future geotechnical developments. We emphasize that this report is valid for this project as outlined above, and should not be used for any other site. Our report is prepared for the exclusive use of our client. No other party may rely on the product of our services unless we agree in advance to such reliance in writing. If you have any questions, or if we may be of further assistance, please do not hesitate to contact our office at (425) 485-5519. Respectfully submitted, KRAZAN & ASSOCIATES, INC. Ben Clawson Staff Geologist BBC/slc: 4 Sean L. Caraway, P.E. Geotechnical Division Manager �, CA r• . Krazan & Associates, Inc. Eleven Offices Serving The Western United States 091_-061 19 doc 4F AwAa —4, 4 Wei -"J.:. NJ. SIT tiff: ON 04 za f,�� . �. � ��_�_.__�-_yam tt n8s _101 Ar. rl r r t e4 F_ - — 7, n k Note: Figure generated from Maptech, Inc. Copyright 1999 KRAZAN & ASSOCIATES FIGURE I —VICINITY MAP 19501 144" Avenue Northeast Location: Edmonds, Washington #1;-300 Job No.: 092-06119 Woodinville, WA 98072 Client: Mike and Sabina Norton 425-485-5519 Date: 7/12/06 a L N a 0 L CL d o, LA o, o, u d Q LEGEND Test Pit TP-1 Location j rnry Rnnrl L N CL 0 L CL d o, a, o� u d Q Undeveloped Land/Wetland ,-,,iTe rLan Proposed Single Famlly Residence Edmonds, WA Figure 2 No scare Job Numbers 092-0E_19 Dsiw July 6, EOOG 1E KX`' l & ASSOCIATES, INC- WQw'p TypflO Md1'1 Log of Borings Laboratory Testing a v ti APPENDIX A FIELD INVESTIGATION AND LABORATORY TESTING Field Investieation Appendix A Page A.1 The field investigation consisted of a surface reconnaissance and subsurface exploration program for the proposed single family residence. Three exploratory test pits were excavated and sampled for subsurface exploration at this site. The exploratory test pits ranged in depth from approximately 4.5 to 5.5 feet below existing grades. The approximate exploratory test pit locations are shown on the site plan (Figure 2). The depths shown on the attached test pit logs are from the existing ground surface at the time the test pits were excavated. The soils encountered were logged in the field during the exploration and, with supplementary laboratory test data, are described in accordance with the Unified Soil Classification System (USCS). All samples were returned to our Woodinville laboratory for evaluation. The logs of the exploratory hand auger borings along with the laboratory test results are presented in this appendix. Laboratory Testin The laboratory testing program was developed primarily to determine the in situ moisture condition and grain size distribution of the soils. The sieve analysis tests were performed for the purpose of soil classification. Test results were used as criteria for determining the engineering suitability of the surface and subsurface materials encountered. The results of the moisture content tests are presented on the Logs of Test Pits (presented in this appendix). The sieve analysis test results are presented in this appendix. Krazan & Associates, Inc. Eleven Offices Serving The Western United States 092-061 19doc Project: Norton Single Family Residence Log of Test Pat TP-1 Project No: 092-06119 Client: Sabina Norton Surface Elevation: Figure No: A-1 Location: Edmonds, Washington Datum: Logged By: CM Depth to Water Initial: Not Encountered At Completion: SUBSURFACE PROFILE SAMPLE Dynamic Cone y Water Content rn E � Penetration (ado) Description a o Test (Blows/1-3/4 in) L m uJ d Y a) o 40 (D T aa) ai 20 40 60 80 20 60I 01 0_ Ground Surface SILTY SAND (SM) ' Loose, fine to medium grained sand, dark brown, moist. Roots and other organic material. -Grab ---------STapsoilfj,------------------ SILTY SAND WITH GRAVEL (SM) Loose, fine to coarse grained sand, reddish brown, moist. Rootlets, occasional organic material, and trasJSome- 5_::' ' iron oxide staining - Decrease in silt content beginning at 3 feet. _____ (Weathered Whidbey FormationZ__ POORLY GRADED SAND WITH GRAVEL (S Dense to very dense, very fine to fine grained s trace silt, grayish brown, moist. - Test pit terminated at 5.5 feet due to refusal. (Whidbey Form ion 10—• End of Test Pit 15— 20 Excavation Method: Bobcat 435ZHS Trackhoe Krazan and Associates Test Pit Date: 26 June 06 1 501 144th Ave. NE #F-300 Contractor: Client Provided Woodinville, WA 98072 Sample Method: Grab Sheet: 1 of 1 Project: Norton Single Family Residence Log of Test Pit TP-2 Project No: 092-06119 Client: Sabina Norton Surface Elevation: Figure No: A-2 Location: Edmonds, Washington Datum: Logged By: CM Depth to Water Initial: Not Encountered At Completion: SUBSURFACE PROFILE SAMPLE Dynamic Cone Water Content m rn Penetration (%) Description o Test (Blows/1-3/4 in) L E a E n f/1 Q Y a)a C� Wp �- 0 -� WI am > o cn U) T a) o o a) co a a 20 40 60 80 20 40 60 80 0_ Ground Surface SILTY SAND (SM) - Loose, fine to medium grained sand with occasional gravel, dark brown, moist. Rootlets _ --------LToQsailY------------------- • - t'r " SILTY SAND (SM) Loose, fine to medium grained sand with occasional small gravel, yellowish brown, moist. Rootlets Iron oxideGrab 5_ staining beginning at 21 inches ------ jWeathered Whidbey Formationi------- POORLY GRADED SAND WITH GRAVEL (SP) Dense to very dense, very fine to fine grained sand with trace silt, olive brown to grayish brown, moist Some iron oxide staining. - Fine grained (SW) interbedded sand layer between 28 and 36 inches. 10— (WhibeX Formation End of Test Pit 15- 20- 25— Excavation Method: Bobcat 435ZHS Trackhoe Krazan and Associates Test Pit Date: 26 June 06 19501 144th Ave, NE #F-3 0 Contractor: Client Provided Woodinville, Wry 98072 Sample Method: Grab Sheet: 1 of 1 Project: Norton Single Family Residence Log of Test Pit TP-3 Project NO: 092-06119 Client: Sabina Norton Surface Elevation: Figure No: A-3 Location: Edmonds, Washington Datum: Logged By: CM Depth to Water Initial: Not Encountered At Completion: SUBSURFACE PROFILE SAMPLE Dynamic Cone Water Content i aD rn m Penetration (%) Description � o Test (Blows11-314 in) CL CL m v o a) W 0--- W I I80 W o >, rn rn >1 (D F- o n 0- 20 40 60 80 20 40 60 _. 0_ Ground Surface SILTY SAND (SM) Loose, fine to medium grained sand, dark brown, moist. Roots. • _ ---------tTopsoilL------------------ - SILLY SAND WITH GRAVEL (SM) _ Loose, fine to medium grained sand, dark yellowish brown to olive brown, moist. Iron oxide staining begins at 2.5 - ra 5 feet. - -----SWeathered Whidbey Formationl-------- POORLY GRADED SAND WITH GRAVEL (SP) Dense to very dense, very fine to fine grained sand. olive brown to grayish brown, moist. Some iron oxide staining. - Fine grained, laminated sand lense from 4 to 4.5 feet. (Whidbey Formation) 10— End of Test Pit 15- 20- 25— Excavation Method: Bobcat 435ZHS Trackhoe rasa and Associates Test Pit Date: 26 June 06 19501 144th Ave. NE #F-300 Contractor: Client Provided Woodinville, WA 98072 Sample Method: Grab Sheet: 1 of 1 Particle Size Distribution Report 100 90 80 70 0= W 60 Z_ Ll Z 50 LU U Ir W 40 30 20 10 0 I I I 1 1 1 1 1 I 1 1 I I I I I 1 1 k,1 I 1 i I I I 1 V I I r I 1 t 1 I , I I I I I 1 I 1 I 1 + 1. .L� , L'.- 1 I r 1 1 I I 1 1 1 1 I I 1 + i ..i- fi f 1 r 1 1 I 1 i•-- I I i 1 1 1 I I I I I I 1 I I 1 I 1 { I 1 r I 1 - - -- - I i T I 1I 1 1 1 I l 1 I 1 � 1 I 1 I 1 f 1k 1 1 cnn 1 CIA 1 n 1 0.1 0.01 0.001 (RAIN S17E - mm %COBBLES % GRAVEL % SAND CRS, MEDIUM FINE % FINES CRS. FINE SILT CLAY 0.0 19.0 11.8 3.8 11.3 38.2 15.9 SIEVE SIZE PERCENT FINER SPEC." PERCENT PASS? (X=NO) 1.5 in. 100.0 1 in. 85.5 .5 in. 78.0 .375 in. 74.2 #4 69.2 #10 65.4 #20 62.2 #40 54.1 #60 36.4 #100 24.6 #200 15.9 Material Description Yellowish -brown silty SAND with gravel. Atterbero Limits PL= LL= P1= Coefficients D85= 24.9 D60= 0.598 D50= 0.370 D30= 0.198 D15= D10= Cu= Cc= Classification USCS= SM AASHTO= A-2-4(0) Remarks Sample ID: 23199-13. TP-3/S-2 @ 1.83' (no specification provided) Sample No.: 23199-B Source of Sample: Test Pit Samples Location: Test Pit 3, Sample No. 2 Date: 7-3-06 Elev./Depth : 1.83' 100 90 8C 7C Cr W 6C Z U_ Z 5C W C) Ir LU 4C d 3C 2( 1( 0 500 Particle Size Distribution Report C 2 N W � N 2 4 8 $ � N 1 Y717 I V _- GRAIN GRAIN SIZE - mm GRAVEL % SAND % FINES %COBBLES CRS. FINE CRS. I MEDIUM FINE SILT I CLAY 0.0 7.3 9.9 1 3.8 1 8.2 30.2 40.6 SIEVE SIZE PERCENT FINER SPEC! PERCENT PASS? (X=NO) 1.25 in. 100.0 1 in. 95.8 .5 in. 89.7 .375 in. 86.5 #4 82.8 #10 79.0 #20 75.5 #40 70.8 #60 65.0 #100 56.6 #200 40.6 Material Description Yellowish -brown silty SAND with gravel. Atterbera Limits PL= LL= PI Coefficients D85= 7.95 Dgp= 0-180 D50= 0.111 D30= 1315= D10= Cu= Cc= Classification USCS= SM AASHTO= A-4(0) Remarks Sample ID: 23199-A TP-2/S-5 @ 4' - (no specification provided) Sample No.: 23199-A Source of Sample: Test Pit Samples Location: Test Pit 2, Sample No. 5 KRAZAN & ASSOCIATES, INC. Date: 7-3-06 Elev./Depth: 4' General Earthwork a Specifications • � 4 'Q l F" APPENDIX B EARTHWORK SPECIFICATIONS GENERAL Appendix B B.I When the text of the report conflicts with the general specifications in this appendix, the recommendations in the report have precedence. SCOPE OF WORK: These specifications and applicable plans pertain to and include all earthwork associated with the site rough grading, including but not limited to the furnishing of all labor, tools, and equipment necessary for site clearing and grubbing, stripping, preparation of foundation materials for receiving fill, excavation, processing, placement and compaction of fill and backfill materials to the lines and grades shown on the project grading plans, and disposal of excess materials. PERFORMANCE: The Contractor shall be responsible for the satisfactory completion of all earthwork in accordance with the project plans and specifications. This work shall be inspected and tested by a representative of Krazan and Associates, Inc., hereinafter known as the Geotechnical Engineer and/or Testing Agency. Attainment of design grades when achieved shall be certified to by the project Civil Engineer. Both the Geotechnical Engineer and Civil Engineer are the Owner's representatives. If the contractor should fail to meet the technical or design requirements embodied in this document and on the applicable plans, he shall make the necessary readjustments until all work is deemed satisfactory as determined by both the Geotechnical Engineer and Civil Engineer. No deviation from these specifications shall be made except upon written approval of the Geotechnical Engineer, Civil Engineer or project Architect. No earthwork shall be performed without the physical presence or approval of the Geotechnical Engineer. The Contractor shall notify the Geotechnical Engineer at least 2 working days prior to the commencement of any aspect of the site earthwork. The Contractor agrees that he shall assume sole and complete responsibility for job site conditions during the course of construction of this project, including safety of all persons and property; that this requirement shall apply continuously and not be limited to normal working hours; and that the Contractor shall defend, indemnify and hold the Owner and the Engineers harmless from any and all liability, real or alleged, in connection with the performance of work on this project, except for liability arising from the sole negligence of the Owner of the Engineers. TECHNICAL REQUIREMENTS: All compacted materials shall be compacted to a density not less than 95 percent of maximum dry density as determined by ASTM Test Method D1557 as specified in the technical portion of the Geotechnical Engineering Report. The results of these tests and compliance with these specifications shall be the basis upon which satisfactory completion of work will be judged by the Geotechnical Engineer. SOIL AND FOUNDATION CONDITIONS: The Contractor is presumed to have visited the site and to have familiarized himself with existing site conditions and the contents of the data presented in the soil report. Krazan & Associates, Inc. Eleven Offices Serving The Western United States 091-06119.doc Appendix B B.2 The Contractor shall make his own interpretation of the data contained in said report, and the Contractor shall not be relieved of liability under the contractor for any loss sustained as a result of any variance between conditions indicated by or deduced from said report and the actual conditions encountered during the progress of the work. DUST CONTROL: The work includes dust control as required for the alleviation or prevention of any dust nuisance on or about the site or the borrow area, or off -site if caused by the Contractor's operation either during the performance of the earthwork or resulting from the conditions in which the Contractor leaves the site. The Contractor shall assume all liability, including Court costs of codefendants, for all claims related to dust or windblown materials attributable to his work. SITE PREPARATION Site preparation shall consist of site clearing and grabbing and preparations of foundation materials for receiving fill. CLEARING AND GRUBBING: The Contractor shall accept the site in this present condition and shall demolish and/or remove from the area of designated project, earthwork all structures, both surface and subsurface, trees, brush, roots, debris, organic matter, and all other matter determined by the Geotechnical Engineer to be deleterious. Such materials shall become the property of the Contractor and shall be removed from the site. Tree root systems in proposed building areas should be removed to a minimum depth of 1 foot and to such an extent which would permit removal of all roots larger than 1 inch. Backfill or tree root excavation should not be permitted until all exposed surfaces have been inspected and the Geotechnical Engineer is present for the proper control of backfill placement and compaction. Burning in areas, which are to receive fill materials, shall not be permitted. SUBGRADE PREPARATION: Surfaces to receive Structural fill shall be prepared as outlined above, excavated/scarified to a depth of 12 inches, moisture -conditioned as necessary, and compacted to 95 percent compaction. Loose and/or areas of disturbed soils shall be moisture conditioned and compacted to 95 percent compaction. All ruts, hummocks, or other uneven surface features shall be removed by surface grading prior to placement of any fill material. All areas scheduled to receive fill materials shall be approved by the Geotechnical Engineer prior to the placement of any of the fill material. EXCAVATION: All excavation shall be accomplished to the tolerance normally defined by the Civil Engineer as shown on the project grading plans. All over excavation below the grades specified shall be backfilled at the Contractor's expense and shall be compacted in accordance with the applicable technical requirements. FILL AND BACKFILL MATERIAL: No material shall be moved or compacted without, the presence of the Geotechnical Engineer. Material from the required site excavation may be utilized for construction site fills provided prior approval is given by the Geotechnical Engineer. All materials utilized for constructing site fills shall be free from vegetable or other deleterious matter as determined by the Geotechnical Engineer. Krazan & Associates, Inc. Eleven Offices Serving The Western United States 092-06119.doc Appendix B B.3 PLACEMENT, SPREADING AND COMPACTION: The placement and spreading of approved fill materials and the processing and compaction of approved fill and native materials shall be the responsibility of the Contractor. However, compaction of fill materials by flooding, ponding, or jetting shall not be permitted unless specifically approved by local code, as well as the Geotechnical Engineer. Both cut and fill shall be surface compacted to the satisfaction of the Geotechnical Engineer prior to final acceptance. SEASONAL LIMITS: No fill material shall be placed, spread, or rolled while it is frozen or thawing or during unfavorable wet weather conditions. When the work is interrupted by heavy rains, fill operations shall not be resumed until the Geotechnical Engineer indicates that the moisture content and density of previously placed fill are as specified. Krazan & Associates, Inc. Eleven Offices Serving The Western United States 09?-06119,doc