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HomeMy WebLinkAboutCT 01-03; CALAVERA HILLS VILLAGES E-1; REPORT OF ROUGH GRADING; 2003-12-02t 7 -i--- :.'.. 4 * 4 7 1 7 7 1 "7 4 - I '•,,.I4•.4 - 7''. '' -, -. '- - 7 4 1 4 1 - :Jron GeochniaI . Geologic. mental' I .1 fr T p .Geotechnical • Geologic Environmental • - 5741 Palmer Way • Carlsbad California 92008 • (760) 438-3155 • FAX (760) 931-0915 4 ' • Revised December 2,2003 ' .5 's W.O. 34597B-SC'5 - .•• - ' .- ' -,çalavèra'Hills II, LLC. 2727 Hoover Avenue National City, California 91950 Attention Mr. Don Mitchell - - - •- .' ''.',' 5- . '-•• ' Subject: Report of Rough Grading, Calavera Hills, Village' E-1, Pads I through. 28, Carlsbad Tract 01-03,City of Carlsbad, San Diego County, California • Dear Mr Mitchell .This report presents a summary of the geotechnical testing and observation services - 'I provided by GeoSoils, Inc. .5(GSI), during the rough earthwork: construction phase of:. development. at the subject site.. Earthwork commenced in FebrUary, 2003, and was generally completed in May, 2003. This report does not include utility and pavement construction testing and observations A report of observation and testing services for 'such work will be provided under a separate cover. • . '... S PURPOSE OF EARTHWORK - : . , .' - . •., -S. The purpose of grading was to prpáre relatively level. pa'ds .for the construction, of 28 residential structures and access roadways. Cut-and-fill grading and drill-and-shoot blasting techniques were utilized to attain the desired graded configurations. ,Existing .'.- topsoils and colluvium were removed to suitable bedrock material and recompacted Cut pads and the cut portion of transition pads were overexavated in order to provide for more I uniform foundation support and/or to facilitate construction. Additionally, street areas were overexcavated to at least -.1 foot below lowest utility import elevation to facilitate . improvement construction. The grading plans for this potion of Calavera Hills, Village E-1, prepared- by Hunsaker & Associates' Inc.,. San Diego, dated 'February 13, 2003, are included with this report as Plates 1 through 4 EARTH MATERIALS 'Subsurface geologic cóñditions exposed during the process of rough grading were observed by a representative of GSI Earth materials onsite generally consist of dense - granitic/metavolcanic rock with athin, discontinuous surficial veneer of topsoil/colluvium. Dense surficial outcrops of granitic/volcanic bedrock were noted throughout the area GROUNDWATER Naturally occurring groundwater was not encountered during rough grading of the building pads and should not affect the proposed building construction provided that the recommendations contained in this report and/or provided by GSl are incorporated into final design and construction, and that prudent surface and subsurface drainage practices are incorporated into the construction plans Based on the fractured and dense nature of the granitic/metavolcanic bedrock; perched groundwater conditions may develop in the future due to excess irrigation, homeowner altered drainage or damaged utilities, and should be anticipated. Should manifestations of perched conditions (i.e., seepage) develop in the future, this office could assess the conditions and provide mitigative recommendations as necessary A discussion of near surface slope subdrainage is presented in our referenced report on toe drains (GSl, 1998d). A discussion of other subdrainage is presented in a later section of this, report EARTHWORK CONSTRUCTION Earthwork operations have been completed in general accordance with the City of Carlsbad grading ordinance and the guidelines provided in the field by this office. Observations during grading included removals, overexcavation and subdrain construction along with general grading procedures and placement of compacted fills by the contractor Rough Grading Preparation of Existing Ground 1 Deleterious material, such as concentrated organic matter and miscellaneous debris, were stripped from the surface and disposed of beyond the limits of grading for the subject area, prior to placing any fill 2 Loose surficial materials (i.e., existing topsoils, previously-placed fills, colluvium, older alluvium and near surface paleosols) were removed to expose competent bedrock in all areas to receive fill 3 In order to provide for more uniform support of structures, the cut portion of transition pads were overexcavated to a minimum depth of 3 feet below pad grade, then brought to grade with compacted fill Cut pads exposing dense Calavera Hills ii, LLC ' • • • • • WO. 3495-B-SC • Calavera Hills, Village E-1 • '' • ' ' '• • • Revised December 2, 2003 '. File e \wp9\3400\3459b rror Page 2 GeoSoits, Inc. granitic/volcanic rock were overexcavated a minimumof 3 feet below pad grade in order to facilitate foundation and utility construction. Where possible, an attempt was made to slope the overexcavated bottom toward the street area. Subdrainage of these areas does not appear necessary at this time. 4 In order to facilitate utility construction, street areas exposing dense bedrock material were overexcavated to at least 1 foot below lowest utility insert 5. In areas where conventional cut-and-fill grading techniques were not feasible due to rock • hardness, drill-and-shoot blasting techniques were utilized. These techniques were used where dense, non-rippablerock occurred within a minimum of 3 feet of finish pad grade, and above local street elevations equivalent to approximately 1 foot below the lowest utility invert elevation. Blasting operations occurred within the Street area in the general vicinity of Pads 1 through 9. 6. Subsequent to completing removals, areas to receive compacted fill were scarified toa minimum depth of 12 inches, moisture conditioned to at least optimum moisture content, and then compacted to attain a minimum relative compaction of 90 percent. These areas were then brought to grade with fill compacted to a minimum 90 percent relative compaction 6 All processing of original ground in areas to receive fill, shown on Plates 1 through 4, was observed by a representative of GSI Fill Placement Fill consisted of onsite and import materials which were placed in thin lifts, approximately 4 to 8 inches in thickness, brought to at least optimum moisture content, and compacted toattain a minimum 90 percent relative compaction. CàmpactiOn test results on fills are , presented in the attached Table 1. Approximate as-built fill Thicknesses are presented in the attached Table 2 The preparation of some of these materials including processing of shot rock and oversize rock through a rock crusher. This process generally produced "6-inch minus" material, in accordance with guidelines presented in GSI (2002) Rock fills were not placed within this site. • 0 • Fill materials generated onsite, or within the larger Calavera Hills development, from either raw excavation or produced at-the crusher site, have been placed in general accordance with recommendations presented in GSI (2002). An additional criteria, developed for this project during grading, has included gradation testing (in cieneral accordance. with ASTM D-422) of stockpiled materials produced from.the rock crusher. This testing has been performed in order to determine the percentage of "fines" included in the stockpile material. For this project, "fines" are áonsidered to be earth materials that are 3/4 inch in diameter, or finer. Suitable soil fills are considered to consist-of earth materials with at least 40 percent finer than 3/4 inch (GSI, 2003b) Caiavera Hills Ii, LLC W.O. 3495-13-SC • Calavera Hills, Village E-1 Revised December 2, 2003 FiIe:e:\wp9\3400\3459b.rror Page 3 GeoSoils, Inc. Slopes . .. - . .. Planned Slopes In general,. graded slopes constructed-under the purview of this report should perform satisfactorily with respect to gross and surficial stability, under normal conditions of irrigation (discussed later), and rainfall, provided that these slopes are properly maintained. Fill slopes .constructed under the purview of this report were provided with a keyway excavated into suitable bedrock material in general accordance with recommendations presented in Southern California Soils and Testing, Inc. (SCST, 1988) and as provided in the field by this office. Cut slopes were constructed using cut and fill grading techniques and/or blasting, and exposed dense igneous and/or metavolcanic rock A detailed analysis of slope stability has been completed under separate cover (GSl, 1998c). Temporary Slopes Temporary construction slopes may generally be constructed at a gradient of 1:1* (horizontal to vertical) or flatter in compacted fill, and 1/2 1 (horizontal to vertical) in suitable bedrock material (provided adverse geologic structures are not present) Utility trenches may be constructed in accordance with guidelines presented in Title 8 of the California Code of Regulations for Excavation, Trenches and Earthwork with respect to Type B soil (compacted fill) and stable rock (bedrock) Construction materials and/or stockpiled soil should not be stored within 5 feet from the top of any temporary slope Temporary/permanent provisions should be made to direct any potential runoff away from the top of temporary slopes Natural Slopes Natural slopes should perform satisfactorily with respect to gross and surlicial stability, under normal conditions of irrigation and rainfall Field Testing 1. Field density tests were performed using the sand cone method (ASTM D-1 556) and nuclear method (ASTM D-2922). Tests taken for the entire Calavera Hills project were taken in consecutive numerical order. Only the test results for Village E-1 are presented in Table 1 at the end of this report. The approximate locations of field density tests are shown on the Compaction Test Location Map, Plates 1 through 4, which utilize the 40- scale grading plans (sheets 4 through 7), prepared by Hunsaker & Associates, San Diego, *Inc.,, as abase map 2. Field density tests were taken at periodic intervals and random locations to check. the compactive effort provided by the contractor. Based on the operations • Calavera Hills ii, LLC • .. • . • W.G.3495-B-SC • Calavera Hills Village E-1 Revised December 2 2003 File e \wp9\3400\3459b rror Page 4 GeoSoils, Inc. observed, test results presented herein are considered representative of the fills observed under the purview of this report 3 Visual classification of the soils in the field, as well as random laboratory testing, was the basis for determining which maximum dry density value to use for a given density test 4.'. Testing was performed on a full-time basis LABORATORY TESTING Moisture-Density Relations The laboratory maximum dry density and optimum moisture content for each major soil type. was determined according to ASTM Test Method D-1557-91. The following table presents the test results arx MAXiMUM DRY OPTIMUM MOISTURE Z. SOIL TYPE. :.. DENSITY cONTENT(%) .. . G -Grayish Brown, Gravelly SAND . 131.0 10.0 H -Grayish Brown, Gravelly SAND (processed) 131.0 . . ... I -Grayish Brown, GravellySAND (processed) 134.0 . 8.5 Expansive Soils Expansive soil conditions have been evaluated for the site. Representative samples of soil near pad grade were recovered for classification and expansion testing. Expansion Index. '1 (E I ) testing was performed in general accordance with Standard 18-2 of the 1997 Uniform Building Code (UBC) .1 Representative expansion indices indicate that site soils near pad grade, within the subject pads, are very low to low expansive (E.l <50). A summary of soil expansion results are. presented in the attached Table 2 Soil Sulfate/Corrosion Typical samples of the site materials were analyzed for corrosion/soluble sulfate potential. Soil sulfate testing indicates that the sulfate exposure to concrete is negligible, in accordance with Table 19-A-4 of the 1997 UBC Corrosion testing indicates moderately Caiavera Hills ii, LLC : . .. W.O. 3495B5C Calavera Hills, Village E-1 .. . . . . Revised December 2, 2003 . File e \wp9\3400\3459b rror Page 5 GeoSolls, Inc. corrosive conditions for buried metal pipe in contact with soil for saturated conditions.- Test results are included in Appendix B.: Alternative methods and additional comments may be obtained from a qualified corrosion engineer. . Sieve Analysis Sample gradation for various representative samples was determined in general accordance. with 'A'STM Test Method 0-422. Test results are presented as• Plates B-i through B-5 in Appendix B RECOMMENDATIONS - FOUNDATIONS General The foundation design and construction recommendations are based on laboratory testing and engineering analysis of onsite earth materials by GSl. Recommendations 'for conventional foundation systems are provided in the following sections. The foundation . ' .'.. systems may be used to support the proposed structures, provided they are founded in. 4. competent bearing material. The proposed foundation systems should be designed and constructed in accordance with the guidelines contained in the UBC. All footing designs : should be reviewed by the project structural engineer Based on the as-built.-fill thicknesses (i.e., differential fill thickness exceeding 3:1, maximum to minimum, across the pad) and soil expansion potential, post-tension foundations are not required for the pads.. under the purview of this report. Post-tension (PT) or conventional foundations may be used. Recommendations for each type of foundation system arepresentedin the following sections Conventional Foundation Design 1. . Conventional spread and continuous footings maybe Used to support the proposed U... residential structures provided .they are founded entirely in properly compacted fill ' or other competent, bearing 'material (i.e., bedroOk). .Footings should not. simultaneously bear directly on bedrock and fill soils 2; Analyses indicate that an allowable bearing value of 2,000 pounds per square foot.. (W 'may be used for design of continuous footings per the attached Table 3, and for design of isolated pad footings 24 inches square and 18 inches deep into: •. properly compacted fill or bedrock The bearing value may be increased by one-third for seismic or other temporary loads. This value. may be increased by . ?° percent for each additional 12 inches in depth, to a maximum of 2,500 psf. No • increase, in bearing, for footing width is recommended Calavera Hills ii, LLC ' . . ' . ., ' . . . W.O. 3495-B-SC Calavera Hills, Village E71 ....... . . . .' . ' ' Revised December 2, 2003 Fiie:e:\wp9\3400\3459b.rror . . . ,. .. ' . ' ' . . ' ' ' . ' . •' Page 6 GeoSoils, Inc. 3. For lateral sliding resistance, a.0.4 coefficient of friction may be utilized for a concrete to soil contact when multiplied by the dead load . 4. Passive earth pressure may be computed as an equivalent fluid having a density of 300 pounds per cubic foot (pcf) with a maximum earth pressure of 2,500 psf. . 5. When combining passive pressure and frictional resistance,,the passive pressure component should be reduced by one-third 6. Footings should maintain a horizontal distance or setback between any adjacent slope face and the bottom outer edge of the footing. The horizontal distance may . be calculated by using h/3, where (h) is the height of the slope. The horizontal setback should not be less than 7 feet, nor need not be greater than 40 feet (per code). The .setback may be maintained by simply deepening the footings. . Flatwork, utilities or other improvements within a zone of h/3 from the top of slope may be subject to lateral distortion. Footings, flatwork, and utilities setbacks should be constructed in accordance with distances indicated in this section, and/or the . ... approved plans.. 7. Provided that the recommendations contained in this report are incorporated into . •• final design and construction phase of development, a majority (>50 percent) of the anticipated foundation settlement is expected to occur during construction.. Maximum settlement is not expected to exceed approximately 1/2.jflCh and should occur below the heaviest loaded columns. Differential settlement is not anticipated. . to exceed ¼ inch between similar elements, in a 20-foot span. Conventional Foundation/Concrete Slab Construction The following construction recommendations are based on generally very low to low expansive bearing soils and maximum fill thicknesses of less than approximately 30 feet. Conventional continuous footings should be constructed in accordance with . recommendations presented in Table 3, and in accordance with the 1997 UBC. All. .. footings should be reinforced per Table 3 Detached isolated interior .or exterior piers and coluñins should be founded at a minimum depth of 18 inches below the lowest adjacentground surface and tied to the main foundation in at least one direction with a grade beam. Reinforcement . should be properly designed by the project structural engineer. A grade beam, reinforced as above, and at least 12 inches square, should be . • provided across the .garage entrances. The base of the reinforced grade beam should be at the same elevation as base of the adjoining footings. . . Calavera Hills ii, LLC .. . . . . W.O. 3495-B-SC Calavera Hills, Village E-1 . . Revised December 2, 2003 File:e:\wp9\3400\3459b.rror . . • • . Page 7 GeoSoils, Inc. . .. • . 4. The residential floor and garage slabs should have a minimum thickness of 4 inches, in accordance with Table 3. Concrete used in floor slab construction should have a minimum compressive strength of 2,500 psi. Concrete slabs should be underlain with a minimum of .-4 inches of sand. In addition, a vapor barrier consisting of a minimum of 10-mil, polyvinyl-chloride membrane, with all laps sealed, should be provided at the mid-point of the sand layer. The slab subgrade should be free of lOose and uncompacted material prior to placing concrete.. Concrete floor slabs (residence and garage) should be reinforced per Table 3. All slab reinforcement, should be supported to ensure proper mid-slab height positioning. during placement of the concrete. "Hooking",of reinforcement is not an acceptable method of positioning. 7. Presaturation is not considered nécessaryforthese soil conditions; however, the moisture content of the subgrade soils should be equal to or greater than optimum moisture to a depth of 12 inches below the adjacent ground grade in the slab areas, and verified by this office within 72 hours of the vapor barrier placement. Soils generated from footing excavations to be used onsite should be compacted ' to a minimum relative compaction 90 percent of the laboratory standard, whether• it is to be placed inside the foundation perimeter or in the yard/right-of-way areas. This material must not alter positive drainage patterns that direct drainage away from the structural areas and toward the street. Proposed pools and other appurtenant structures should consider that excavation difficulties will likely be encountered in some pads at depths greater than approximately 3 feet below existing building pad grades due to the presence of dense granitic rock. Pjease refer to Table 2 for a listing of pads with relatively shallow (i.e., <10 feet) fills. 10. As an alternative, an engineered PT foundation system may be used. Recommendations for PT slab design are presented in the -following Section. PT Slab Foundation Systems ' • • '• 1; PT slabs may be utilized for construction of typical one- and two -story residential structures onsite. The information and recommendations presented in this section • are not meant to supercede design by a registered structural engineer or civil engineer familiar with PT slab design or corrosion engineering consultant. Càlavera Hills II, LLC W.O. 3495-5 SC Calavera Hills, Village E-1 • • • Revised December 2, 2003 • FiIe:e:\wp93400\3459b.rror • • • • • • Page 8 GeoSoils, Inc. 2. From a soil expansion/shrinkage standpoint, a fairly common contributing factor to distress of structures using PT slabs is a significant fluctuation in the moisture content of soils underlying the perimeter of the slab, compared to the center, causing a "dishing" or "arching" of the slabs To mitigate this possible phenomenon, a combination of soil presaturation (if necessary, or after the project has been dormant for a period of time) and construction of a perimeter "cut off" wall grade beam may be employed 3 For very low to low (E I 0 through 50) expansive soils, perimeter and mid span beams should be a minimum 12 inches deep below lowest adjacent pad grade. The perimeter foundations may be integrated into the slab design or independent of the slab The perimeter beams should be a minimum of 12 inches in width A vapor barrier should be utilized and be of sufficient thickness to provide an adequate separation of foundation from soils (10 mil thick). The vapor barrier should be lapped and adequately sealed to provide a continuous water-resistant barrier under the entire slab The vapor barrier should be sandwiched between two 2-inch thick layers of sand (SE > 30) for a total of 4 inches of sand 4 Isolated piers should be incorporated into the PT slab system 5 Specific soil presaturation for slabs is not required for very low expansive soils, however, the moisture content of the subgrade soils should be at or above the soils' optimum moisture content to a minimum depth. of 18 inches below grade, depending on the footing embedment 6 PT slabs should be designed using sound engineering practice and be in accordance with the Post-Tension Institute (P11), local and/or national code criteria and the recommendations of a structural or civil engineer qualified in PT slab design. Alternatives to P11 methodology may be used if equivalent systems can be . proposed which accommodate the angular distortions, expansion parameters, and settlements noted for this project If alternatives to P11 are suggested by the structural consultant, consideration should be given for additional review by a qualified structural PT designer. Soil related parameters for PT slab design, are presented on the following Caiavera Hills ii, LLC. . . . . . .. W.O. 3495-B-SC Calavera Hills, Village E-1 . .. . . . Revised December 2, 2003 File e \wp9\3400\3459b rror Page 9 GeoSoils, Inc. . . . -. '. -... . ._-• ..- . Perimeter -Footing Embedment* 12" Allowable bearing value 1 000psf** Modules of subgrade reaction 125 psi/inch Coefficient of friction 0.35 Passive pressure. . . . 275 pcf. . Soil Suction (Pf)' ' . . . 3.6 .• Depth.to Constant Soil Suction 5 feet Thornthwaite moisture . . S . . -20.0 . . em edge . . . . .. s : 2.5 . . . em center . . . 5.0 . my ed . . . .0.25 . my center . .. . . . . 1.00 Minimum Slab Thickness 5 inches * Lab data indicates E.I. 0-50 for this site. '• . .. . . : **B.I g for slab on grade only, bearing value for interior or perimeter beams should be in accordance with parameters provided-for conventional continuous . and isolated spread footings. .. . . . . Provided that the recommendations contained in this report are incorporated into final design and construction phase of development, a majority (>50 percent) of the. anticipated foundation settlement is expected to occur during construction. Maximum settlement is not expected to exceed approximately ½ inch, and should occur below the heaviest loaded columns. Differential settlement is not anticipated .to -exceed 1%-inch between similar elements, in a 20-foot span. .. Designers of PT slabs should reviewthe parameters provided for PT slabs, and compare using a span distance of 5 feet, using a module of subgrade reaction of 125 psi in their evaluation. . . . . .. 8. In accordance with guidelines presented in the UBC improvements and/or footings should maintain a horizontal distance, X, between any. adjacent descending slope • face and the bottom outer, edge of the improvement and/or footing. The horizontal b. distance, X, may be calculated by using X = h/3, wher h is the height of the slope.. : X should not be less than 7 feet, nor need not be greater than 40 feet. X may be maintained by deepening the footings. Improvements constructed within a distance . of h/3 from the top of slope may be subject to lateral distortion. Foundations for any adjacent structures, including retaining walls, sho.uld be d.eepened (as necessary) to below: a 1:1 projection, upward and away from any. . proposed lower foundation system. .,This recommendation may not be considered .. valid, if the additional surcharge imparted by the upper foundation on the lower foundation has been incorporated into the design of the lower foundation: . .. Calavera Hills II, LLC . . . W.O. 3495-B-SC . Calavera Hills, Village E-1 . ' . . • . Revised December 2, 2003 File:e:\wp9\3400\3459b.rror Page 10 GeoSoils, Inc. .' .. .• .. S.. • •. .. ,. S I L . :, • , . S ........ .• ... ''.r . _'.•.'f'"' .. . - - Additional setbacks, not discussed or superceded herein,- and presented in the 1997 .UBC are considered valid. : EXTERIOR FLATWORK Exterior driveways, walkways, sidewalks, or . patios, using concrete slab on grade. construction should be designed and constructed in accordance with the following criteria: Driveway slabs should be a minimum 4 inches in thickness; all other exterior slabs may be a nominal 4 inches in thickness. A thickened edge 'Shouldbe considered for all flatwork adjacent to landscape areas.- Slab subgrade should be compacted to a minimum 90 percent relative compaction. and moisture conditioned to at or above the soils optimum moisture content. •, The use of transverse and longitudinal control joints should be considered to help control slab cracking due to concrete shrinkage or, expansion. Two of the best ways to control this movement are: 1) add a sufficient amount of reinforcing steel, increasing tensile strength .of the slab; and/or 2) provide an adequate amount of. control and/or expansion joints,to accommodate anticipated concrete shrinkage and expansion. We would suggest that the maximum control joint spacing be N. placed on 5 to 8 foot centers or the smallest dimension of the' slab, whichever is least. :' No traffic should be allowed upon' the newly poured concrete slabs until they have been properly cured to within 75 percent of design strength... 5 Positive site drainage should be maintained at all times Adjacent landscaping should be graded to drain into the street, parking area, or other approved area. All surface water should be appropriately directed to areas designed for site drainage.' 6.. . . Concrete compression strength should be a minimum of 2,500 psi. CONVENTIONAL RETAINING WALLS/WALLS General Foundations may be designed using parameters provided in the Design Section of the Foundation Recommendations presented herein. Wall sections should adhere to the County of. San Diego and/or City of Carlsbad: guidelines. All wall 'designs should be-- reviewed byaqualified structural engineer for structural capacity, overturning, and seismic resistance stability per the 1997 UBC Caiavera Hills II, LLC - . ' ' . ' . ' ' - W.O. 3495-B-SC - Calavera Hills Village E-i '. . . . Revised December 2, 2003 File:e:\wp9\3400\3459b.rror. . .. , ' ' , Page 11 . GeoSoils, Inc.' ' • • ' ' ' - assume that select onsite or equivalent very low expansive soils are used to backfill retaining walls, from a 1:1 (horizontal to vertical) projection upward and away from the heel fo the footing. If expansive soils are used to backfill the proposed walls within this wedge, increased active and at-rest earth pressures will need to be utilized for retaining wall design. Heavy compaction equipment should not be used above a 1:1 projection up and away from the bottom of any wall. The following recommendations are not meant to apply to specialty walls (cribwalls, loffel, earthstone, etc.). Recommendations for specialty walls will be greater than those provided herein, and can be provided Upon request. Some movement of the walls constructed should be anticipated as soil strength parameters are mobilized. This movement could cause some cracking dependent upon the materials used to construct the wall. To reduce wall cracking due to settlement, walls should be internally grouted and/or reinforced with steel. Restrained Walls Any retaining walls that will be restrained priorto placing and compacting backfill material or that have re-entrant or male corners, should be designed for an at-rest equivalent fluid pressures of 60 pcf, plus any applicable surcharge loading. For areas of male or re-entrant corners, the restrained wall design should extend a minimum distance of twice the height of the wall (2H) laterally from the corner. Building walls below grade, should be water-proofed or damp-proofed, depending on the degree of moisture protection desired. Refer to the following section for preliminary recommendations from surcharge loads. Cantilevered Walls These recommendations are for cantilevered retaining walls up to 15 feet high. Active earth pressure may be used for retaining wall design, provided the top of the wall is not restrained from minor deflections. An empirical equivalent fluid pressure (EFP) approach may be used to compute the horizontal pressure against the wall. Appropriate fluid unit weights are provided for specific slope gradients of the retained material. These do not include other superimposed loading conditions such as traffic, structures, seismic events or adverse geologic conditions. SURFACE SLOPE EQUIVALENT. OF RETAINED.MATERIAL FLUID WEIGHT PCF (HORIZONTAL:VERTICAL) LOWEXPANSIVE SOIL) (VERY Level 35 2tol 45 Calavera Hills II, LLC W.O. 3495-B-SC Calavera Hills, Village E-1 S Revised December 2, 2003 File:e:\wp9\3400\3459b.rror Page 12 GeoSoils, Inc. -'','.,'-'F'_.• '''"' - The equivalent fluid density should be increased to 60 pcf for level backfill at the angle point of the wall (corner or male re-entrant) and extended a minimum lateral distance of 2H on either side of the corner. Traffic loads within a 1:1 projection up from the wall heel, due to light trucks and cars should be considered as a load of 100 psf per foot in the upper 5 feet of wa!l in uniform pressure. For preliminary design purposes, footing loads within a 1:1 backfill zone behind the wall will be added to the walls as one-third of the bearing pressure for one footing width, along the wall alignment. Sound Walls- Foundations for top of slope sound walls, using concrete block construction, maybe constructed in accordance with conventional foundation recommendations presented in this report. Foundations should maintain a minimum lateral distance of 7 feet from the outside bottom edge of the wall' footing to the face of any adjacent slope.' Wall Backfill and Drainage '• ....' ' ' ' ' " All retaining walls should be provided with an adequate gravel and pipe back drain and "'• ' outlet system to prevent buildup of hydrostatic,pressures, and be designed in accordance with minimum standards presented herein. Retaining wall drainage and outlet.systems should be reviewed by the project design civil engineer and incorporated into project plans. Pipe should consist of schedule 40 perforated PVC pipe'. Gravel used in the back drain systems should be a minimum of 3 cubic feet per lineal foot of %- to 11/2-inch clean' crushed rock encapsulated in filter fabric (Mirafi 140 or equivalent). Perforations ,in pipe. ,should facedown. The surface of the backfill should be sealed, by, pavement or the top 18 inches compacted to 90 percent relative compaction with native, soil. Proper surface ,drainage should also be provided. ' ' As an alternative to gravel back drains, panel drains' (Mirädrain 6000, Tensar, etc) may be ' used. Panel drains should be installed per manufacturers guidelines., Regardless of the ,back drain used, walls should be water proofed where they would impact living areas or, where staining would be objectionable Wall Footing Transitions ", '•". ' •' , ' ",.' ' ' ' . . ' Site walls are anticipated to be supported on footings designed in accordance with the recommendations in this report. Wall footings may transition from bedrock to fill. If this ' condition' is present the civil designer may specify either: a) 'A minimum of a 2-foot, overexcavation and 'recompaction of bedrock. materials, as; measured for .a distance. of 2H 'from the transition in the. •' " direction of the wall. Overéxcavations should, be completed for a minimum lateral. distance of ,2 feet beyond the footing, measured perpendicular to the wall. Caiavera Hills Ii, LLC - ' ' - ' ' ' ' ' W.O. 3495-B-SC' Calavera Hills, Village E-1 ' ' , ' ' Revised December 2, 2003 -- File:e:\wp9\3400\3459b.rror ' ' ' , - - , . •' ' ' ' Page 13 - ' • -' ' '' -' . •; GeoSoils, Inc. ' •• - •'• Increase the amount of reinforcing steel and wall detailing (i.e., expansion joints or crack control joints) such that a angular distortion of 1/360 for a distance of 2H on either side of the transition may be accommodated. Expansion joints should be sealed with a flexible grout. Embed the footings entirely into native formational material. If transitions. from but to fill transect the, wall footing alignment at an angle of less than. 45 degrees (plan view), then the designer should follow recommendation "a" Ii '(above) and until such transition is between 45 and 90 degrees to the wall alignment PAVEMENTS Pavement design' for streets has not been performed to date. Concrete driveway pavements outside the public right of way may be constructed per the exterior concrete ' slab recommendations presented in this report. Based on, the type of earth materials• encountered, minimum pavement sections (per City standards) may be anticipated. Final pavement design .will be provided upon completion of underground improvements and .A-value testing. ,: .. '. .• ' bEVELOPMENTCRITERIA Graded Slope Maintenance and Planting Water has been shown to weaken'. the inherent strength of all earth materials. Slope' stability is significantly reduced by overly wet conditions. Positive surface drainage away from graded slopes should be maintained and only the amount of irrigation necessary to sustain plant life should be provided for planted -slopes.: Over-watering should be avoided' as it can adversely affect site improvements. Graded slopes constructed within 'and utilizing onsite materials would be erosive. Eroded.debris may be minimized and surficial slope stability enhanced by establishing and maintaining a suitable vegetation cover soon after construction. Compaction to the face of fill slopes would tend to minimize short-term, erosion until vegetation is established. Plants selected for landscaping should be light weight,' deep rooted types that require little ,water, and are capable of surviving the prevailing climate. If plants are selected other than those recommended above', the potential for perched water conditions to develop will increase.. Recommended plant selection and.irrigation practices should,be provided to each individual homeowner, as " described above and below. ' '. : '.' • '. . . • ' . S ' •, Landscape Maintenance. . ' •,• , : , , . . . . . . .. ' :. Only the amount of irrigation necessary to* sustain plant life should be provided. Over watering the landscape areas could adversely affect proposed site improvements, and will , • Caiavera Hills ii, LLC • • : . . . • W.O. 3495-B-SC • Calavera Hills, Village E-1 ' '. • • ' • . • Revised December 2, 2003. Fi1e:e:\wp9\3400\3459b.rror '' . ' S ' • . . Page 14 , I GeàSoIls, Inc. •, • .' . • . . ' increase the potential for perched water to develop The slope areas should be planted with drought resistant vegetation. Consideration should be given to the type of vegetation chosen and their potential effect upon surface improvements (i.e., some trees will have an effect on concrete flatwork with their extensive root systems). . From a géotechnical standpoint, leaching is. not recommended for establishing : landscaping. If the surface soils are processed for the purpose of adding amendments, they should be recompacted t090 percent minimum relative compaction., Drainage Positive site drainage should be maintained at all times, and should be incorporated into . . homeowner improvements. Drainage should not flowuncontrolled down any descending slope.. Water should be directed away from foundations and not allowed to pond and/or seep into the ground.. Pad drainage should be directed toward the street or other approved area. Roof gutters and down spouts should be considered to control roof drainage. Downspouts should outlet a minimum of3 feet from proposed structures and/or in accordance with the recommendations of the design civil engineer. We would recommend that any proposed open bottom planters adjacent to proposed structures be eliminated for a minimum distance of 10 feet As an alternative, closed bottom type planters could be utilized An outlet placed in the bottom of the planter could be installed to direct drainage away from structures or any exterior concrete flatwork. Owing to the nature of site materials, the potential for perched groundwateri as a result of contrasting permeabilitiesof fill and/orbedrock, may not be precluded. Accordingly, perched water conditions should be anticipated subsequent to grading. Should such conditions develop, this office should be contacted to provide mitigative recommendations Footing Trench Excavation All footing excavations should be observed by a representative of this firm subsequent to trenching and Driorto concrete. form and reinforcement plaóement. The purpose of the observations is to verify that the excavations are made into the recommended bearing material and to the minimum widths and depths recommended for construction If loose or compressible materials are exposed within the footing excavation, a deeper footing or . 2 removal and recompaction of the subgrade materials would be recommended at that time. All excavations should minimally conform to CAL-OSHA and local safety codes Footing trench spoil and any excess soils generated from utility trenchexcavations shOuld be compacted to a minimum relative compaction of 90 percent if not removed from the site Caiavera Hills ii, LLC . . . W.O. 3495-B-Sc Calavera Hills Village E-1 Revised December 2 2003 Fi1e:e:\wp9\3400\3459b.rror . . . . . . . . . Page 15 GeoSoits, Inc. 1... . 2.•• ... - ... . . .. Additional Site Improvements If, in.the future, any additional improvements are planhed for the site, recommendations concerning the geological or geotechnical aspects of design and construction of said improvements could be provided upon request. Proposed pools or other appurtenant structures should consider that excavation difficulties will likely be encountered in some .'. pads (see-Table 2) at depths greater than '3 feet below existing building pad grade. Subdrainage should be provided for spa and pool homeowner improvements. Additional Grading ' ' . . . '• . : This office should be notified in advance of any additional fill plaäement, regrading of the site, or trench backfilling after rough grading has been completed. This includes any 'grading, utility trench, and retaining wall backfills. All excavations should be. observed by one of our representatives and conform to CAL-OSHA and local safety codes. Utility Trench Backfill '• ' ' . 1. All interior utility trench backfill should be brought to at least 2 percent above'. .. optimum moisture content and then compacted to obtain a minimum relative ' .. compaction of 90 percent of the laboratory standard. As an alternative for shallow (12 inch to 18 inch) under-slab trenches, sand having a sand equivalent value of 30. . , . or greater may be utilized and jetted or flooded into place. Observation, probing ' and testing should be provided to verify the desired results.' 2." Exterior trenches adjacent to, and within areas extending' below a 1:1 plane projected from the outside bottom edge of the footing, and all trenches beneath hardscape features and in slopes, should be compacted to at least 90 percent of thelaboratory standard. Sand backfill, unless excavated from the trench, should . not be used in these backfill areas. Compaction testing and observations, along.. with probing, should. be accomplished to verify the' desired results: 3 All trench excavations should conform to CAL-OSHA and local safety codes PLAN REVIEW Final foundation and improvement plans, including homeowner improvement plans (as .\ described, below), should be submitted to this office for review and, comment, as they' \become available, to minimize any misunderstandings between the plans and ecommeidations presented herein In addition,' foundation excavations and earthwork' construction performed on the site should be observed and tested by this office If. L conditions 'are,' found to differ, substantially from those . stated, appropriate. ' 'rè'c'dih'méndations would be. offered at that time. • • • . : . ' ' • ..' '• CalaveraHills II, LLC . • • . ' . • W.O. 34957E SC ' çalave,'ra'HilIs, Village E-i ' • ' . . , Revised December 2, 2003 Fie: e:\wp9\34OO\3459b.rror . ' ' , , Page 16 GeoSoils, Inc. :, . ... . : :. . •.• SUMMARY OF RECOMMENDATIONS REGARDING. GEOTECHNICAL OBSERVATION AND TESTING ,. We recommend that observation and/or testing be performed by the geotechnical' consultant at each of the following construction stages During grading/recertification After excavation of building footings,retaining wall footings, and free standing walls •' ' footings, prior to the placement of reinforcing steel or concrete . . During retaining wall subdrain installation, prior to backfill placement.: .' During placement of backfill for area drain, interior plumbing, utility, line trenches, and retaining wall backfill . Afterpresoaking/presaturation of building 'pads and other flatwork subgrade, prior to the placement of reinforcing steel or concrete During slope construction/repair. When any unusual soil or groundwater conditions are encountered during any construction operations, subsequent to the issuance of this report When homeowner improvements, including flatwork, spas, pools, walls, etc, are constructed REGULATORY COMPLIANCE Removals, processing of original ground cuts, and fills have been observed and compaction testing performed under the purview of this report have been completed using the selective testing and observations services of GSI. Earthwork was found to be in •': compliance with the Grading Code of the City of.Cárlsbad, California. Our findings were • • made and recommendations prepared in conformance.'.with generally accepted professional, engineering practices and no further warranty is implied nor made. This • report is subject. to review by the controlling authorities for this project. .GeoSoils, Inc. • ..' should not be held responsible nor liable for work, testing, or recommendations performed or provided by others Calavera Hills II, LLC ' • • ,. ' • • • W.O. 3495-B-SC Calavera Hills, Village E-1 • ' • ' • - • . • Revised December 2, 2003 ' • ' File:e:\wp9\3400\3459b.rror ' ..• • • • • : • • ' .. , - • • • • Page 171. GeoSoils, Inc. .. . . .... The opportunity to be of service is sincerely appreciated. If you should have any questions, please do not hesitate to call our office. . . ,Respectfully submitted4' GeoSoils, Inc 'I \ Reviewed by , - t 34 1 Robert G. Cri man Skelly Project Geologist, CEG f 934: ---" Civil Engineer, ACE 47857 AGC/DWS/J PF/j k/Jh Attachments: Table 1 -Field Density Test Results' . . . . Table 2 Pad Characteristics .. . . ... . Table 3 - Foundation Construction Recommendations . . .: Appendix A - References Appendix B. - Laboratory Test Results . . . . .. . . . Plates 1 through 4 - Field Density Test Location Maps ... . ... . . .. Distribution: (4) Addressee . . . .. . . .. . . .. . '1 Caiavera Hills Ii, LLC . . . . . . ,. WO. 3495-B-SC Calavera Hills, Village E-1 . . . . . Revised December 2, 2003 FiIe:e:\wp9\3400\3459b.rror : . . . . - Page 18 GeOSoils, Inc.,. . . . . . . F'.i,' ,' '.P" , NO NO OR DEPTH (ft) :llIOIsrJ.JRE CONTENT (%) DRY' DENSITY COMP (%) METHOD S.OIl. TYPE 514 2/19/03 Pad 23 : Village E-1 367.0 10.4 120.0 91.6 NO . 515 2/19/03 Pad 23 Village E-1 365.0 10.9 1212 92:5 . ND G 516 2/19/03 ' Pad 23 Village E-1 368.0 10.2 119.3 91.1 NO G 517 2/19/03 ' Pad-28 Village E-1 362.0 9.9 120.3 91.8 NO G 518 .. 2/19/03 Pad 16 Village E-1 362.0 10,2 .' 118.4 90,4 NO G 668 3/10/03 Bldg 21 Village E-1 374.0 10.3 .126.8 91.2 NO LI 670 3/10/03 . . Bldg 21 . Village E-1 376.0 9.9 126.5 91.0. NO H 672 3/10/03 Bldg 11 Village E-1 373.0 10.1 126.4 90.9 NO ' H - 674 3/10/03 .Bldg 12. Village E-1 372.0 , 10.5 126.9 91.2 NO. H .,676 3/11/03 Bldg 10 : ' Village E-1 374.0 10.2 126.4 90.9' NO H 677 3/11/03 Bldg 11 Village E-1 374:0 10.3 126.1 90.7 NO H :678 3/11/03 . Bldg 11 , Village E-1 375.0 10.5 . 126.9 91.2 NO H 695 3/17/03 Pad 10 ' Village E- •. 375.0 10.6 120.1 91.7 NO. H 696 3/17/03 . Pad 10. Village E-1 374.0 11.2 .120.9 92.3 NO H .697 3/17/03 ' Pad 10 , Village E-1 376.0 - 9.9 121.6 92.8 NO . .698 3/17/03 . Pad 10 . Village E-1 376.0 10.5' 119.5 91.2 NO H '699 ' 3/17/03 Pad 24 . Village.E-1 367.0 , 10.1 118.9 . 90.8 NO 706 3/18/03 . . ' ' Rec Pad . Village E-1 368.5 9,4 . '.120.3 91.8 NO H.' 707 3/18/03 ' Rec Pad Village E-1 370,5 9.1 120.8 '92.2 NO . 750 '3/18/03 .Pad 22 ' Village E-1 .369.0 9.5 ' 118.2 90.2 ND Li 1751 3/18/03. . Pad 24 Villaqe:E-1 371.0 10.1 ' 120.9 92:3 NO _H_ 752 3/18/03 Pad 22 'Village E-1 370.0 . 9.6 ' 122.5 93.5 NO H 767. 3/24/03 Pad 8 Village E-1 375.0 10.2 119.6 . 91.3 NO ' _H_. 768 3/24/03 . Pad 9 . Village E-1 376.0 .11,1 118.8. 90.7 . NO _H' 1769 3/24/03. Pad24 Village__ E- 371.0 .. '9.2 121.2 92.5 NO. _H_ 770 3/24/03 Pad 22 Village E-1 373.0 9.9 _. .119.3 91.1 ND, H. '.771 3/24/03 Pad26 __... Village E-1 .370:0 10:4 .- .119.7 91.4 NO H• 772 3/24/03 Pad27 Village E-1 367.0 . .9,6 121.7 - 92.9 SC _. H 773 3/25/03 Pad 93- _. Village E- . 364:0 ' ' 1.0.2'. 118.9 90.8 NO , H 774 3/25/03. ' Pad 24 Village E-1: 369.0 11.8 .119.5 91.2 ' NO H• .775 3/25/03 Pad 27 '' VillageE-1 366.0.. 11.1 _' 119.2. 91.0 NO 'i-I .776' . 3/25/03' . Pad 27 VillageE-1 .368.0 .11.4 , 122.4 93.4 NO L J77 3/26/03' Pad28 Village E-1 '360.0' . 12.2 121.6 92.8 NO _. ' H.. 778 . 3/26/03 'Pad 28 Village E-1 :355:0 11.9 120:0 .91.6 . NO H. 779 3/26/03 Pad 28 _. Village E-1 ' 361.0 ..11.2 _. 119.3 91.1 . NO H 1780 3/26/03. ' Pad27 _. Village E-1 368.0 10,4 ' 121.2 92,5 . NO . H' 781' 3/26/03 Pad 25-26 Village E-I . 372.0 11.1. 119.6.. 9.1.3 NO H 782 .3/26/03 .Pad 15 _' Village E-1 359.0 , 12.0 1187 90.6 - ND ' : H 789 4/1/03 PrivateDrivePadA Village E-1 . 355.0 10.2 121.7 92.5 NO . 790 4/1/03 - _..Pad 14.' Village E-1 356.0. 11.9 124.8 95.3 NO H 791*._' 4/1/03 Pad14 Village E-1 360.0 4.8 112.1 85.6 ' NO. H 791A 4/1/03 Pad 14 Village E-1 .360.0 9.2 _112.7 90.6 ND H "792 4/1/03 . -Pad 14 __. Village E- 363:0 11.0 1189 90.8 NO H. 793 4/1/03 - _Pad 14_' Village E-1 361.0 ' 10.9 ' 123.3 94.1 1 NO 794 4/1/03 ..Pad 1 Village E-1 362.0 .11.6 120.1 91.7 .ND ' H. 795 4/1/03 . _Pad 2____. .Village-E-1 362.0 10.3 1203 92.2- . NO. . H 796 4/1/03 Pad Village '363.0 . . .9.1 118:9 90.8 . NO H, 797 4/1/03 . -Pad 2 . Village E- .364.0 9.4. 1 ,120.0_. 91.6 ND H. TEST NO. DATE TEST LOCATIOX.N TRACT NO. _____ ELEV OR DEPTH (ft) MOISTURE CONTFNT - - DRY DENSITY !L REL COMP (%) TEST METHOD SOIL TYPE - 798 4/1/03 Front Pad 15 Village E- 363.0 10.1 - 18.3 - 90.3 ND H 824 3/31/03 Pad 18 Village E-1 369.0 102 119.8 91.5 ND H - 825 3/31/03 Pad 19 Village E-1 371.0 9.8 121.3 92.6 ND H -. 826 3/31/03 Private Drive Pad A Village E-1 350.0 9.3 122.3 93.4 ND H 827 4/4/03 Pad 14 Village E-1 355.0 9.9 120.3 91.8 ND H 828 4/4/03 Pad 20' Village E-1 375.0 10.3 121.3 92.6 ND H 829 4/4/03 Pad 7 Village E- 372.0 10.4 123.7 94.4 ND H 830 4/4/03 Pad 19 Village E-1 373.0 _9L_ 121.7 92.9 ND H 838 4/8/03 Pad 17 Village E-1 368.0 108 121.4 92.7 ND H 839 4/8/03 Pad 17 Village E-1 370.0 _112 123.4 94.2 ND H 840 4/8/03 Pad 25 Village E-1 370.0 11.1 123.8 94.5 ND H 841 4/8/03 Pad 25 Village E-1 372.0 _105 123.1 94.0 ND H 867 4/1/03 Private Drive B Village E- 363.0 9.1 122.1 91.1 ND 868 4/11/03 Private Drive B Village E-1 367.0 8.9 122.6 91.5 ND I - - 869 4/11/03 Pad Village E- 351.0 9.6 123.4 92.1 ND - - 870 4/11/03 Pad 3 Village E-1.356.0 9.3 123.9 92.5 ND - - 884 4/16/03 Pad 3 Slope Face Village E-1 362.0 14.2 109.6 90.9 ND _A_ 885 4/16/03 Pad 3 Slope Face Village E-1 360.0 14.5 109.2 90.6 ND _A 886 4/16/03 Pad 3 Slope Face Village E-1 363.0 14.4. 109.4 90.7 ND A 895 4/17/03 Pads 3-4 (Sewer Easement) Village E- 362.0 9.6 _124.5 92.9 ND - - 896 4/17/03 Drive B 27+50 . Village E-1 354.0 9.1 25.7 - 93.8 ND - - 897 4/18/03 12+50 Private Drive Village E-1 354.0 9.8 _121.9_9_ 90.9 ND - - 898 4/18/03 11+40 Village E-1 356.0 9.5 122.2 91.1 ND - - 899 4/18/03 10+20 Village E-1 356.0 9.3 121.7 90.8 ND - - 900 4/18/03 Pad 3 Village &1 366.0 9.1 121.8 90.8 ND - - 922 4/23/03 Pad 5 Village E- 369.0 9.3 126.9 94.7 SC - - 923 4/23/03 Pad 4 Village E-1 368.0 8.6 127.6 95.2 ND - - 924 4/23/03 Pad 3 Village E-1 366.0 8.2 124.9 93.2 ND - - 933 4/24/03 Private Dr B 14+00 Village E-1 370.0 9.3 127.2 94.9 SC - - 934 4/24/03 Private Dr B 12+50 Village E-1 363.0 10.1 125.4 93.6 ND - - 935 4/24/03 Private Dr B 11 +30 Village E-1 360.0 9.6 127.8 95.4 ND - - 936 4/24/03 Private Dr B 13+50 Village E-I 369.0 8.4 124.4 92.8 ND - - 937 4/24/03 Private DrBll+90 Village E-1 364.0 9.8 123.0 91.8 ND - - 943 4/25/03 Private Dr B 14+90 Village E-1 370.0 _97 127.0 94.8 ND - - 944 4/25/03 Private Dr B 19+50 Village E-1 360.0 _10 12-2.9'.91.7 ND - - 945* 4/25/03 Private Dr B 21+00 Village E-1 359.0 129 116.4 86.9 ND - - 945A 4/25/03 Private Dr B 21+00 Village E-1 359.0 _10 125.6 93.7 ND - - 946 4/25/03 Private Dr B 22+50 Village E-1 358.0 9.9 123.5 92.2 Sc - - 947 4/25/03 Private Dr B 20+00 Village E-1 364.0 11.5 128.4 95.8 ND - - 948 4/25/03 Private Dr B 21 +00 Village E71 361.0 10.9 124.9 93.2 ND - - 955 4/29/03 Private Dr B 17+30 Village E-1 365.0 9.3 122.3 91.3 ND - - 956* 4/29/03 Front Pad 23 Village E- i 366.0 10.2 119.5 88.4 ND - -• 956A 4/29/03 Front Pad 22 Village E-1 366.0 9.7 125.4 93.6 ND - - _957 4/29/03 Front Pad 23 Village E-1 367.0 10.0 121.8 90.9 ND 958 4/29/03 Front Pad 23 Village E-1 369.0 9.1 126.1 94.1 ND - - 959 4/29/03 End Pad 14 Village E-1 360.0 8.6.*126.1 94.1 ND - 960 4/29/03 End Pad 14 Village E-1 363.0 8.8 127.3 95.0 ND - 961 4/29/03 Private Dr B 23+50 Village E-1 357.0 9.1 124.2 92.7 ND - - ...- .• TEST NO. ......DE TEST LOCATION TRACT NO. ELEV OR MOISTURE CONTENT DRY DENSITY REL COMP TEST METHOD SOIL TYPE: 1962 4/29/03 Private Dr B 25+50 Village E-1 355.0 9.0 123.1 91.9 ND - - FG-965 5/1/03 Bldg 27 Village E-1 FG 9.6 129.2 96.4 ND - - FG-966 5/1/03 Bldg 26 Village E-1 FG 8.7 127.7 95.3 ND I- FG-967 5/1/03 Bldg 24 Village E-1 FG 8.6 127.6 95.2 ND - - FG-968 5/1/03 Bldg 8 Village E-1 FG . 9.0 126,8 94.6 ND - FG-970 5/1/03 Bldg 7 Village E-1 FG 8.2 125.8 93.9 ND - FG-971 5/1/03 . Bldg 6 Village E-1 FG 8.9 126.9 94.7 ND - FG-1007 5/9/03 Pad 3 Village E-1 FG 103 128.4 r 95.8 ND - - FG-1008 5/9/03 Pad 4 Village E-1 FG . 10.1 128.9 96.2 ND - FG-1009 .5/9/03 Pad 5 Village El FG 9.6 126.1 94.1 ND - - FG-1010 5/9/03 Pad 18 Village E-1 FG 9.9 125.3 93.5 ND - - FG.1011 5/9/03 Pad 19 Village E-1 . FG 10.5 121.7 90.81 ND - - FG-1012 5/9/03 Pad 20 . Village E-1 FG. . 11.0 126.0 94.0 ND I- FG-1013 5/9/03 Pad 9 Village E-1 FG 10.1 129.3 96.5 ND - FG-1014 .5/9/03 .Pad 10 . Village E-1 FG 9.0 124.8 . 93.1 ND - FG-1015 5/12/03 Pad 28 . Village E-1 FG 9.1 126.4 94.3 ND _l FG-1016 5/12/03 Pad 15 • Village E-1_ FG 8.6 122.7 .91.6 ND I FG-1017 5/12/03 Pad 16 . Village E-i .FG .8.5 . .124.9 93.2 ND - - FG-1018 5/12/03 .Pad 17 . Village, E-1 FG .8.9 124.6 93.0 ND - - FG-1019 5/12/03 Pad 25 Village E-1 FG. . 9:6 124.2 92.7 ND - - 1027 5/13/03 Private Dr C 10+80 . Village E-1 362:0 . 10.0 121,9 91.0 ND - - 1028 5/13/03 Private Dr 11+80 Village E-1 364,0 10.2 121.8 90.9 ND - - FG-1033 5/14/03 Bldg 11 • Village El FG 8.6 124.4 92.8 ND - - FG-1034 .5/14/03 .Bldg 12 VillageE-1 FG. 9.2 125.8 93.9 ND 1 FG-1035 5/14/03 Bldg 21 Village E-1 FG 8.5 128.1 95.6 ND - - FG-1036 5/14/03 Bldg 23 Village E-1 .• FG 8.4 123.8 .92.4 ND. I FG-1037 5/14/03 Bldg 14 . Village E-1 FG 9.2 127.0 94.8 ND = FG-1038 5/14/03 .Bldg 1 Village E-1 .FG 91.1 126.1 94,1 ND - FG-1039 5114/03. . Bldg 2 . . . Village E-1 FG 9,3•• 124.9 93.2 ND I 1063 5/20/03 . Pad 13 . Village E-1 370.0 9:8 124.9 93,2 ND I 1064 5/20/03 Pad 13 Village El 371.0 . 8.8 .126.1: 94.1 ND = 1065 5/20/03 :Private Dr B 23+00 Village E-1 361.0 . 9.1 121.4 90,6 ND I - - 1066 5/20/03 7 Private Dr B 21+20. Village E-1 364.0 10.3 123.3 92.0 ND - 1067 5/20/03 Private Dr B 19+80 Village E-1 366.0.. .10,1 122.1 .91.1 ND I 1097 5/27/03 .Pvt Dr B 16+50 rVillage E-1. 367,0 .. 9.8 • 121.9 91.0 ND - 1098. 5/27/03 Pvt Dr B 16+75 Village E-1 370.0 . 8.7 1. 93.6 .ND - 1099 .5/27/03 Pvt Dr B 16+25 . Village E-1 370.0 9.3 . 123.4 92.1 ND 1100 5/27/03 Bldg 21 Village E-1 374.0, 9.9 1225 91.4 ND - FG-1101 5/27/03 Bldg 22 • Village E-1 .FG 8.6 . 127.2 94.9 ND - - FG-1102 5/27/03 ... Bldg 13 ... Village E-1' FG 8.5 . 127.6 95.2 ND I- - TABLE 2. PAD CHARACTERISTICS PAD E.I. . (per UBC.. Standard 18-2) : EXPANSION. POTENTIAL' SOLUBLE. SULFATE: (weight percent)• , SULFATE . EXPOSURE 2 . . DEPTH . . OF FILL (Range in Ft.) FOUNDATION CATEGORY (3) 1 0 Very Low 0.0064 Negligible 2-4 I 2 0 Very Low 0.0064 Negligible 3-4 . . 3 0 Very Low 0.0064 Negligible 3 : 4 0 Very Low 0.0064 Negligible 3-10 5 0 Very Low . 0.0064 Negligible 3-5 I 6 0 . Very Low 0.0064 Negligible 3-5 7 . 0 . Very Low 0.0064 Negligible . 3-4 8 0 Very Low 0,0064 Negligible 3 . . 9 0 Very Low . 0.0064 Negligible 3-4 10 0 Very Low 0.0064 Negligible 3-6 11 0 Very Low 0.0088 Negligible . 3-5 I 12 0 . Very Low . 0.0088 Negligible . . 3-6 I 13 0 Very Low .0.0088 Negligible 3-4 I 14 0 Very Low 0.0088 Negligible 3-6 . I 15 1 Very Low 0.0088 Negligible 3-4 I 16 1 Very Low 0.0088 Negligible 3-4 I 17 1 Very Low 0.0088 Negligible 3-4 18 1 Very Low 0.0088 Negligible 5 . I 19 1 Very Low 0.0088. Negligible 3-5 I 20 1 . Very Low 0.0088 Negligible . 4-5 I 21 1 Very Low 0.0088 . Negligible 4-5 I 22 2 Very Low 0.0055 Negligible 3-8 23 2 Very Low 0.0055 Negligible. 4-6 . I 24 2 Very Low . .0.0055 . Negligible 4-7 I. 25 2 Very Low 0.0055 Negligible . . 5 . I 26 2 Very Low 0.0055 Negligible 5-6 I Calavera Hills II, LLC Table 2 File:e:\wp9\3400\3459b.rrg Page 1 GeoSoils, Inc. SOLUBLE El SULFATE DEPTH (per UBC EXPANSION (weight SULFATE OF FILL FOUNDATION PAD .Ständard18-2) POTENTIAL' percent) .'EXPOSURE 2> (Range in Ft.) CATEGORY (3) 27 2 Very Low 0.0055J Negligible 57 I 28 2 Very Low 0.0055 Negligible 3 (1) Per Table 18-I-B of the 1997 UBG. (2)*Per Table 19-A-4 of the 1997 UBC. Foundations should be constructed in accordance with recommendations for the specific categories noted above and presented in Table 3. MINIMUM INTERIOR EXTERIOR FOUNDATION FOOTING SLAB REINFORCING INTERIOR! LAB UNDER-SLAB GARAGESLAB. FLATWORK CATEGORY SIZE THICKNESS STEEL REINFORCEMENT TREATMENT REINFORCEMENT REINFORCING I 12 Wide 4 Thick 1- #4 Bar Top #3 Bars @ 2 Sand Over 6 x 6 None x and Bottom 24" o.c. .10-Mil Polyvinyl (10/10) 12 Deep Both Directions Membrane Over WWF 2 Sand Base II 12 Wide 4 Thick 2-,#4 Bars Top #3 Bars @ 2 Sand Over 6 x 6 6 X.61" x and Bottom 18 o.c. 10-Mil Polyvinyl (6/6) (10/10) 18 Deep Both Directions Membrane Over WWF WWF 2 Sand Base III 12" Wide. 4" Thick 2-#5 Bars Top #3Bars@ 2SandOver Same as 6x6 x and Bottom 18 o.c. 10-Mil Polyvinyl Interior Slab (6/6) 24 Deep Both Directions Membrane Over WWF 2 Sand Base p Category Criteria Category I Max Fill Thickness is less than 20 and E I is less than or equal to 50 and Differential Fill Thickness is less than 10 (see Note 1) Category II Max Fill Thickness is less than 50 and E I is less than or equal to 90 or Differential Fill Thickness is between 10 and 20 (see Note 1) Category Ill Max Fill Thickness exceeds 50 E.I.exceeds 90 but is less than 130 Differential Fill Thickness exceeds 20 (see Note 1) 1 PT foundations are required where maximum fill exceeds 50',or the ratio of the maximum fill thickness to the minimum fill thickness exceeds 3 1 Consideration should be given to using PT foundations where the E I exceeds 90 2 Footing depth measured from lowest adjacent subgrade 3 Allowable soil bearing pressure is 2,000 psf 4 Concrete for slabs and footings shall have a minimum compressive strength of 2,000 psi (2,500 psi for exterior flatwork) or adopted UBC minimum at 28 days using 5 sacks of cement Maximum Slump shall be 5 5 Visqueen vapor barrier not required under garage slab However, consideration should be given to future uses of the slab area such as room conversion and/or storage of moisture sensitive materials 6 Isolated footings shall be connected to foundations per soils engineer's recommendations (see report) 7 Sand used for base under slabs shall be very low expansive and have SE > 30 8 Additional exterior flatwork recommendations are presented in the text of this report 9 All slabs should be provided with weakened plane joints to control cracking Joint spacing should be in accordance with correct industry standards and reviewed by the project structural engineer. ) I - APPENDIX A REFERENCES S - S r / I p -I / I I r I / I - 1 S S 4 S I S REFERENCES GeoSoils, Inc., 2003a, Memorandum "review, of grading and' trench backfill recommendations, Calavera Hills II, Carlsbad Tract 00-02, Drawing 390-90, city of Carlsbad, San Diego County, California," W.O. 2863-A-SC, dated August 16, 2002, W.0. 3459-132-SC, May 20 2003b, Memorandum: general discussion of fill quality, Calavera Hills II, Carlsbad, San Diego County, California, W.O. 3459-132-SC, dated May 20. 2003c, Revised geotechnical update, Village E-1 of Calavera Hills II, Carlsbad, San Diego County, California, W.0. 3459-B-SC, May 12 2003d,Geotechnical. update, Village E-1 of Calavera Hills II, Carlsbad, San Diego. County, California, W.O. 34597B-SC,' February 17. S 2002, Review of grading and trench backfill recommendations, Calavera Hills II, Carlsbad Tract 00-02, Drawing 390-90, City of Carlsbad, San Diego County, California, W.O. 2863-A-SC, August 16. ' '• 2000, Update of geotechnical report, Calavera Hills, Village E-i, City of Carlsbad, California, W.0. 2789-A-SC, August 28 1998a, Lack of Paleontological Resources, Carlsbad Tract Nos 83-19, PUD 56, and 83-321 PUD 62, Carlsbad, San Diego County, California, W.0. 2393-B-SC, dated January 21. , / '• '• 1998b, Preliminary review of slope stability, Calavera Hills, Villages ."Q" and "T", City of Carlsbad, California, W..0. 2393-B-SC, dated February 16 1998c, Review of slope stability, Calavera Hills, Villages "Q" and "1," City of Carlsbad, California, W.O 2393-B-SC, dated June 24. 1998d, Toe Drain Recommendations, Calavera Hills, Village 1, City of Carlsbad, California, W.0. 2393-B-SC, dated September 30 Hunsaker & Associates-San Diego, Inc., 1997b, Plans .for the grading of Calavera Hills Village "Q", Carlsbad Tract 83-32, Sheets 1-8, Drawing No. 303-2A, Project No 28933, dated November 17 Southern California.Soil and Testing, Inc.. 1992,.lnterim 'report of as built geology.field S ' observations and relative compaction tests, proposed College Boulevard Improvements and Village El, Carlsbad, California, SCS&T 9121081 , S 1988, Supplemental soil investigation, Calavera Hills Village 0 and T, College Boulevard, Carlsbad, California, job no. 8821142, report no.1,' dated October 6. GeoSoils, Inc. GeoSoils, Inc. ,'44•• . ,. .. .. 4. APPENDIX B LABORATORYTEST RESULTS 1 -. 4 .4 4 '4 '.4 I 4. -.4 4.4 1 -1 .4 -4 -.4 .4 .4 .4. M J. Schiff & Associates, Inc. Consulting Corrosion Engineers - Since 1959 Phone: (909) 626-0967 Fax: (909) 626-3316 431 W. Baseline Road . E-mail laI4mjschzff con: Claremont, CA 91711 . website: rnjsch:ff corn Table 1 - Laboratory Tests on Soil Samples Calavera Hills Your #3459-B-SC, MJS&A #03-0625LAB 30-May-03 . . . . . . . . . Village E-1 Sample ID Village E-1 Village E-1 Lots 2228, Lots 1-6, 14 Lots 15-21 Rec. FG FG FG' Resistivity ' ,Units as-received ' ohm-cm 170,000 ' 48,000 35,000 saturated ohm-cm 2,200 . 1,600 3,300' p} . ' . 6.5 7.3 . 6.7 Electrical Conductivity MS/cm 0.18 ' 0.20 0.13 Chemical 'Analyses Cations ' calcium Ca2+ mg/kg ' 40 , 12 16 magnesium" Mg2" ' mg/kg, ND 10 , ND ,sodium Na mg/kg 75' . 126 77 Anions ' . carbonate CO3 2-mg/kg ' ND ' ND ' - ND bicarbonate HCO3 'mg/kg 67 ' 76 ' 37 . chloride , Cl mg/kg , 100 . 135 85 sulfate •SO4 mg/kg . 64 , 88 55 Other Tests ammonium N}14 mg/kg na na , ' na nitrate NO3 mg/kg na . na na sulfide S2 qual ' na ' na ,na Redox mv na na . na ;'1 1, 11. 44 , '' ' " ' •.'.',.41f Electrical conductivity in millisiemens/cm and chemical analysis were made on a 1:5 soil-to-water extract. mg/kg = milligrams per kilogram (parts per million) of dry soil. . 'Redox = oxidation-reduction potential in' millivolts • ' ' ' I • ' • ND = not detected • • ' na = not analyzed : • ' ' Page lofl • • ' . ' • , , . Figure B-i 100 95 90 85 80 75 70 65 0 iii 60 5 rIf 50 LL 45 z Di 040 cx: Lii o35 30 25 6. U.S. SIEVE OPENING IN INCHES I U.S. SIEVE NUMBERS I HYDROMETER 4 11 2 ic 1 3 6 10 1A16 30 A, 50 1001A(200 u11111111JI III I1!IIUIRIIIIIIII_11111111 III IOUlII'lIIlHII 11111111 11111111 1111111 ___ Ill_llIIlUIIIHIHhI_llllllll_111111111_11111111 Ill UOIhilI•llllllll 11111111 11011111 11111111 iii ioiiuui•iiiinii_11111111_IIIIIII_11111111 III ll0IIIlhi'llllHll 11111111 11011111 11111111 III_IIlIil1iIIiiIll_11111111_IAIIiII_11111111 III ll0IlIlliNIHIl 11111111 11011111 11111111 III_lllhIlIlIlliiHlI_11111111_11111111_11111111 iii uoiiuuiiuuii lull. 11011111 1111111 III_IllhlUlIUl0IflhIlUIlIII_111111111_11111111 ii uoiiiuu-iiuuiunuuiu 11011111 0111111 UI_IlHIIIIII•IOIHII_Hi!iIIl_1011111_11111111 Ill IlllhIIIIIIIIIII IIIIi!U 11011111 11111111 III_IIHIIUIIRIIIIHII_IIIIIIIIROOIIUI_11111111 Ill lillllllilllilli 11111111 IblillI 11111111 Ill IlHIIUuIUIIIIHIU 11111111 IIHIIIIIROIIIUI 100 10 1 0.1 - 0.01 0.001 GRAIN SIZE IN MILLIMETERS COBBLES F GRAVEL SAND SILT OR CLAY . coarse Ifine Icoarse.1 medium fine Sample Depth Classification LL PL P1 Cc Cu .1 El Lot 0.0 1.34 359.62 Sample Depth DIOO D60 D30 DID %Gravel %Sand %Silt I %Clay E-1 Lot 0.0 305 26.735 1.63 39.9 31.2 10.0 GeoSolls, Inc. 5741 Palmer Way Carlsbad, CA 92008 -i' Telephone: (760)438-3155 Fax: (760)931-0915 GRAIN SIZE DISTRIBUTION Project: MCMILLIN Number: 3459-B1-SC Date: May 2003 Figure B-I S • • S IS SI uuiuiiuiaoioiiu__IHIlIlIRIlIlUIl 111IIUI • IIIl1llIIIII.—HIIIIIIiiiiiuimiiiiiuiaiiiiiuia M1111:=IIIIHhI__ :1111 iiiiiiimmiilillom111111 • iii oiuiaoiuuiu H111111 iiiiui iuiuuu III IUIIUIUHIIIIII liiiinmiiiiiimmii I III III liiiinmiiiii lm iuuiuiiuuaiiiiniu :. 1111111 11111111 11111111 III liismiiiiiilmmiiiiiilmmiiiiii 11 11111111 UI iiiiiiiuiiiiiiuiui 1111111 11111111 ill IIIlIIIiIIIIUuI 11111111_11011111 11111111 III Ills 0111111IlII 11111111 IiHiIIiI_11111111 NNE IIIlIIllmmiiiiiiimmiiiiiiimMillillismillillin_ liiiiinmiiiiii 1HHIIIII11111111 III iiiiUui•oiuuu'iiuuiiu 11011111 11111111 UI I mmiiiiiiimmiiiiiilm III II0IlIlIHhIUiI10ilIIU 11011111_11111111 I IIHIIIIIUHIIHII_IHIiii 11111111 11111111 Ill_lI0IIIII'HIIIIII_IHIlIIIiiC1IlII_11111111 III IIIIIlIIIIIlIIHII 11111111 IiHiIIiI 11111111 II I I II III I - I :1 S S . GRAIN SIZE DISTRIBUTION Project: MCMILLIN _I • 5741 y Carlsbad, CA 92008 Telephone: (760) 438-3155 Number: 3459-Bl-SC -- .1 •Figure B-4 L COBBLES GRAVEL I SAND I SILT OR CLAY coarse fine coarse medium - fine I I&A 2/13/03 -. . . WO-. NO 553- 163 . -: WONO553.-163 BIN - -; Tr.-,- - -. --Th- ----- ------ - -T -r--r-- - -V-? - •*çy- T--½. - - 60 C 1liA21'13/0$ - --- :-: - WONO-55J163 - ---- - - --- --- --- - -I-__-__ - - - -