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2002-7744 G ,,ENGINEERING SER VICES DE F CityO � Y initas Capital Improvement Projects `. District Support Services Field Operations Sand Replenishment/Stormwater Compliance Subdivision Engineering Traffic Engineering May 18, 2005 Attn: INSCO Insurance Services, Inc 17780 Fitch Suite 200 Irvine, California 92614 RE: Gunness, Robert and Carol 3839 Megan Lane APN 264-222-04 Grading Permit 7744-G Final release of security Pen-nit 7744-G authorized earthwork, stone drainage, single driveway, and erosion control, all needed to build the described project. The Field Operations Division has approved the project. Therefore, a full release of the security deposit is merited. Performance Bond 8287985, in the remaining amount of$7,032.00 will be released in entirety. The original bond amount was $28,128.00. The document original is enclosed. Should you have any questions or concerns, please contact Debra Geishart at (760) 633- 2779 or in writing, attention this Department. Sincerely, L/ Masih Maher y Lembach Senior Civil Engineer Finance Manager Field Operations Financial Services CC Jay Lembach,Finance Manager Gunness,Robert and Carol Debra Geishart File TF.I. 760-633-2600) / FAX 760-633-2627 505 S. Vulcan Avenue. I ncinitas. California 9202a-36.; I IM -(,!)-6,53-1700 � recycled paper CZtyOf'ENGINEERING SERVICES DEPARTMENT Encinitas Capital Improvement Projects District Support Services Field Operations Sand Replenishment/Stormwater Compliance Subdivision Engineering Traffic Engineering May 3, 2004 Attn: INSCO Insurance Services, Inc 17780 Fitch Suite 200 Irvine, California 92614 RE: Gunness, Robert and Carol 3839 Megan Lane APN 264-222-04 Grading Permit 7744-G Partial release of security Permit 7744-G authorized earthwork, storm drainage, single driveway, and erosion control, all needed to build the described project. The Field Operations Division has approved the rough grading. Therefore, a reduction in the security deposit is merited. Performance Bond 8287985, in the amount of$28,128.00, may be reduced by 75% to $7,032.00. The document original will be kept until such time it is fully exonerated. The retention and a separate assignment guarantee completion of finish grading. Should you have any questions or concerns, please contact Debra Geishart at(760) 633- 2779 or in writing, attention this Department. Sincerely, • Masih Maher ',JLL y Lembach Senior Civil Engineer L finance Manager Field Operations Financial Services CC Jay Lembach,Finance Manager Gunness,Robert and Carol Debra Geishart File TEL 760-633-2600 l FAX 760-633-2627 505 S. Vulcan Avenue, Encinitas, California 92024-3633 TDD 760-633-2700 � recycled paper • Civil Engineering • Land Planning • Structural • Surveying November 27, 2002 .` �%'`� 1 � City of Encinitas ,: Engineering Department `, �✓ �' ^f RE: HYDROLOGY EVALUATION—THE MOEBIU RE NCE PARCEL 1 OF P.M. 14459 —DUSTY TRAIL AND EGAN LANE A.P.N. 264-222-04 This lot is an existing lot from Parcel Map 14459 and received prior approval for a clearing/grubbing permit under Drawing No. 7134-G. The new owners of this property are proposing a single-family residence in substantial conformance to the area delineated on the aforementioned plan. Based on many site visits and review of the actual drainage in this area, it is our opinion that the majority of drainage entering this lot is directed towards the large drainage channel in the Open Space and does not affect the main pad and residence area of the proposed grading plan. Therefore, the only drainage affecting this residence is the pad itself, which is approximately 0.5 acres. Based on the County of San Diego Design and Procedure Manual and assuming rural single family residential conditions, we would conservatively predict no more than 2.0 cfs in a 100-year storm. It is our professional opinion that typical drainage devises utilized for single family residential construction, i.e., brow ditches, sheet flow, swales, berms and area drains will be adequate to handle the anticipated drainage for the actual pad for this site. Ultimately, the overall drainage for this lot will be routed to a drainage ditch to be in conformance to "SUSMP" requirements. As Engineer of Work for this residential grading plan, we respectively request your acceptance of this hydrology evaluation. Should you have any questions or comments, please feel ee to contact this office or respond, as such, with plan check comments. Since, ly, �QPOFESS�p�� LO AN ENGINE NG ��Q Jca�AS E• p ��y o X92 / w C 39726 R, m /j * Exp. 12-31-05 ouglas E. Logan, R.C.E. 39726 `r�q� CIVIL P��P Principal FOF CAL\F� Office: 1635 S. Rancho Santa Fe Road, #209 • San Marcos Mailing: 132 N. El Camino Real, PMB-N • Encinitas, CA 92024 Phone 760-510-3152 • Fax 760-510-3153 Email: dlogan @connect net,com C E J `", E EAST COUNTY SOIL CONSULTATI 3 AND ENGINEERING, INC. 10925 HARTLEY ROAD, SUITE 441! k!AR LJJ4 �---1 SANTEE, CALIFORNIA 92071 619 258-7901 E�NC ^EEiiiG n cS FAX 619 258-7902 Ci?Y OF ENCi%,7AS Mr. Robert C. Gunness 17, 200-2o3 5740 Fleet Street, Suite 100 Project No. 02-1148133(A) Carlsbad, California 92008 Subject: Limited Site Investigation Update Proposed Single Family Residence 3839 Megan Lane, APN 264-220-82 City of Encinitas, California Reference: "Limited Site Investigation, Proposed Single Family Residence, 3839 Megan Lane, APN 264-220-82, City of Encinitas, California", Project No. 02-1148133, Prepared by East County Soil Consultation and Engineering, Inc., Dated 040cer October 17, 2002. Dear Mr. Gunness: In accordance with your request, we have reviewed the referenced soil report and visited the subject site on November 13, 200'). Site conditions were found as described in the referenced limited site investigation report. Therefore, the recommendations provided for the proposed single family residence are still valid. If we can be of further assistance, please do not hesitate to contact our office. Respectfully submitted, QPOFESS11 0 ou s. o lF c� No.0054071 rn Exp- �k Mamadou Saliou Diallo, P.E. RCE 54071 MSD/md EAST COUNTY SOIL CONSULTATION AND ENGINEERING, INC. 10925 Hartley Road, Suite I Santee, California 92071 (619) 258-7901 Fax 258-7902 Mr . Robert C . Gunness October 17, 2002 5740 Fleet Street, Suite 100 Project No . 02-114883 Carlsbad, California 92008 Subject : Limited Site Investigation Proposed Single Family Residence 3839 Megan Lane, APN 264-220-82 City of Encinitas, California Dear Mr . Gunness : In accordance with your request, we have performed a limited investigation of the soil conditions at the subject site. The investigation was undertaken to provide the soil engineering criteria and recommend an appropriate foundation system for the proposed residential development . Our investigation found that the site is underlain by topsoil and colluvium to a depth of approximately 2 . 0 feet within the limits of the proposed construction. Dense rocks of the Santiago Peak Volcanics were underlying the colluvial soils . It is our opinion that the construction of the proposed residence is feasible provided the recommendations herein are implemented during construction. Respectfully submitted, Q�C ESS �Oou S. CD No.CO54071 r^ M d Exp.iz-j�-�� r c1W. Mamadou Saliou Diallo, P . E. �4FCA��� RCE 54071 MSD/jm GUNNESS PROJECT NO. 02-1148B3 INTRODUCTION This is to present the findings and conclusions of a soil investigation for the proposed single family residence to be located on the west side of Megan Lane, in the City of Encinitas, California . The objectives of the investigation were to evaluate the existing soils conditions and provide recommendations for the proposed construction. In order to accomplish these objectives, four exploratory trenches were excavated to a maximum depth of 4 . 5 feet; undisturbed and loose bag samples were obtained, and laboratory tests were performed. SITE DESCRIPTION AND PROPOSED CONSTRUCTION The subject site is located on the west side of Megan Lane, in the City of Encinitas, California . The property slopes gradually to the southwest . A residential development was observed to the east and south, and a vacant land to the west . The proposed construction consists of a single-family residence . It is our understanding that the house will be one-story and founded on continuous footings with a slab-on-grade floor. FIELD INVESTIGATION On May 30, 2002 , four exploratory trenches were excavated to a depth of approximately 4 . 5 feet with a John Deere backhoe. The approximate locations of the trenches are shown on the attached Plate No . 1, entitled "Location of Exploratory Trenches" . A continuous log of the soils encountered was recorded at the time of excavation and is shown on the attached Plates No . 2 and 3 entitled "Summary Sheet" . The soils were visually and texturally classified according to the filed identification procedures set forth on the attached Plate No. 4 entitled "Uniform Soil Classification Chart" . SUBGRADE CONDITIONS Topsoil and colluvium were encountered to a depth of approximately 2 . 0 feet . The topsoil extending to a maximum depth of one foot consisted of loose silty sand with rootlets . The colluvium was made of sandy clay/clayey sand with a soft/loose consistency. 2 i GUNNESS PROJECT NO. 02-I148B3 Dense rocks of the Santiago Peak Volcanics were underlying the colluvium. EXPANSIVE SOILS Expansion index tests were performed on select samples of the colluvium to determine volumetric change characteristics with change in moisture content . Expansion indexes of 2 and 50 were obtained indicating a very low to low potential for expansion. GROUNDWATER No groundwater was encountered during the course of our investigation. The site is approximately 400 feet above mean sea level . We do not expect groundwater to affect the proposed development . However, oversaturated ground conditions at shallow depths may develop due to heavy precipitations, landscape watering, leaking water lines or unforeseen causes . Mitigative measures are discussed in the drainage section of this report . GEOLOGIC HAZARDS A review of the available geological literature pertaining to the site indicates the existence of the Rose Canyon Fault Zone approximately 12 Km to the west . Ground shaking from this fault or one of the major active faults in the region is the most likely happening to affect the site . With respect to this hazard, the site is comparable to others in the general area . The proposed residence should be designed in accordance with seismic design requirements of the 1997 Uniform Building Code or the Structural Engineers Association of California using the following seismic design parameters : PARAMETER VALUE UBC REFERENCE Seismic Zone Factor, Z 0.40 Table 16-I Soil Profile Type Sp Table 16-J Seismic Coefficient, Ca 0.44 Table 16-Q Seismic Coefficient, Cv 0.64 Table 16-R Near-Source Factor, Na 1.0 Table 16-S Near-Source Factor, Nv 1.0 Table 16-T Seismic Source B Table 16-U Based on the absence of shallow groundwater, type and consistency of the bedrock materials (Santiago Peak Volcanics) , it is our opinion that the potential for liquefaction is very low. 3 GUNNESS PROJECT NO. 02-1148B3 CONCLUSION AND RECOMMENDATIONS The following conclusions and recommendations are based upon the analysis of the data and information obtained from our soil investigation . This includes visual inspection; field investigation; laboratory testing and our general knowledge of the soils native to the site . The site is suitable for the proposed development provided the recommendations set forth are implemented during construction. GRADING AND EARTHWORK Site grading should begin with clearing and grubbing, e . g . the removal of brush, vegetation and topsoil . All colluvium under the house pad should be removed and recompacted to a minimum of 90 percent relative compaction while maintaining a moisture content 2 to 3 percent over optimum. The grading plan prepared by Logan Engineering indicates a transition between cut and fill on the house pad. Therefore, to minimize differential settlement, we recommend a minimum of 3 feet of a fill blanket on the house pad. The overexcavation should extend at least 5 feet beyond perimeter footings . Heavy ripping and/or blasting may be required. The fill soils should be moisture conditioned 2 to 3 percent over optimum, placed in thin lifts and compacted to a minimum of 90 percent relative compaction. The actual depth and extent of removal should be evaluated in the field at the time of excavation by a representative of this firm. Grading should be done in accordance with the attached Appendix A. An alternative to the overexcavation and recompaction process is to extend the footings to the Santiago Peak Volcanics . FOUNDATION AND SLAB a . Conventional continuous and spread footings are suitable for the proposed house. Continuous footings should extend a minimum of 12 inches for the one-story structure into the compacted fill soil or the Santiago Peak Volcanics . The footings should be at least 12 inches in width and reinforced with two #5 steel bars; one bar placed near the top of the footings and the other bar placed near the bottom of the footings . b. Concrete floor slabs should be a minimum 4 inches thick. Reinforcement should consist of #3 bars placed at 18 inches on center each way. Slab reinforcement should be placed within the middle third of the slab by supporting the steel on chairs or concrete blocks "dobies" . The slab should be underlain by 2 inches of clean sand over a 10-mil visqueen moisture barrier . The effect 4 i GUNNESS PROJECT NO. 02-1148B3 of concrete shrinkage will result in cracks in virtually all concrete slabs . To reduce the extent of shrinkage, the concrete should be placed at a maximum of 4-inch slump . The minimum steel recommended is not intended to prevent shrinkage cracks . C . Where moisture sensitive floor coverings are anticipated over the slab, the 10-mil plastic moisture barrier should be underlain by a capillary break at least 4 inches thick, consisting of sand, gravel or 3/4 inch crushed rock with no more than 5 percent passing the No . 200 sieve . d. An allowable soil bearing value of 1500 pounds per square foot may be used for the design of continuous and spread footings founded a minimum of 12 inches into the compacted fill soils . This value may be increased by 20 percent for each additional foot of depth to a maximum value of 4500 lb/ft2 as set forth in the 1997 edition of the Uniform Building Code, Table No. 18-1-A. If footings are founded in competent bedrock (Santiago Peak Volcanics) an allowable soil bearing value of 2500 psf may be used. SETTLEMENT Settlement of compacted fill soils is normal and should be anticipated. Because of the minor thickness of the fill soils under the proposed footings, and the light building loads, settlement should be within acceptable limits . DRAINAGE Adequate measures shall be undertaken to properly drain the site after the structure and other improvements are in place, such that the drainage water within the site and adjacent properties is directed away from the foundations via surface swales and subsurface drains towards the natural drainage for this area. Proper surface and subsurface drainage will be required to minimize the potential of water seeking the level of the bearing soils under the foundations, which may otherwise result in undermining and differential settlement of the structure and other improvements . 5 i GUNNESS PROJECT NO. 02-I148B3 LIMITATIONS OF INVESTIGATION The recommendations in this report pertain only to the site investigated and based upon the assumption that the soil conditions do not deviate from those disclosed in the trenches . If any variations or undesirable conditions are encountered during construction, or if the proposed construction will significantly differ from that planned at the present time, East County Soil Consultation and Engineering, Inc. should be notified so that supplemental recommendations can be made. Plates No . 1 through 4 , Pages L-1 through L-3, References and Appendix A are parts of this report . Respectfully submitted, PpFESSIp, Q�QQP'0OU S. Z3 No-0054071 M d EXP. 1Z 3-01 1k aQ. ,9 CI14 1�1�Q, \ Mamadou Saliou Diallo, P . E . RCE 54071 MSD/jm 6 Tv EAST COUNTY SOIL CONSULTATION & ENGINEERING, INC. _ 10925 HARTLEY RD.,SUITE 1,SANTEE.CA 92071 (619)258-7901 Fax(619)258-7902 GUNNESS PROJECT NO. 02-11.18B3 PLATE NO. 2 SUMMARY SHEET NO. 1 TRENCH NO. 1 DEPTH SOIL DESCRIPTION Y M Surface TOPSOIL medium brown, dry, loose, silty sand, rootlets 0 . 6' COLLUVIUM (Qal) red brown, dry, loose 118 . 0 3 . 8 clayey sand 2 . 0 SANTIAGO PEAK VOLCANICS (Jsp) gray brown, dense rocks 3 . 0' bottom of trench, refusal, trench backfilled 05-30-02 -------------------------------------------------------------- TRENCH NO. 2 DEPTH SOIL DESCRIPTION Y M Surface TOPSOIL medium brown, dry, loose silty sand, rootlets 1 . 0' COLLUVIUM (Qal) red brown, moist, soft, sandy clay (CL) 9 . 1 1 . 5' SANTIAGO PEAK VOLCANICS (Jsp) gray brown, dense rocks 2 . 5' bottom of trench, refusal, trench backfilled 05-30-02 -------------------------------------------------------------- 7 GUNNESS PROJECT NO. 02-1148B3 PLATE NO. 3 SUMMARY SHEET NO. 1 TRENCH NO. 3 DEPTH SOIL DESCRIPTION Y M Surface TOPSOIL medium brown, dry, loose, silty sand, rootlets 1 . 0' COLLUVIUM (Qal) medium brown, moist, medium dense clayey sand 2 . 0' gray brown, moist, stiff, 113 . 8 13 . 6 sandy clay 3 . 0' gray brown, moist, stiff, 114 . 0 11 . 7 sandy clay 3 . 5' SANTIAGO PEAK VOLCANICS (Jsp) gray brown, dense rocks 4 . 5' bottom of trench, trench backfilled on 05-30-02 TRENCH NO. 4 DEPTH SOIL DESCRIPTION Y M Surface TOPSOIL medium brown, dry, loose, silty sand, rootlets 0 . 5' COLLUVIUM (Qal) tan brown, dry, loose, clayey sand 1 . 5' SANTIAGO PEAK VOLCANICS (Jsp) gray brown, dense rocks 3 . 5' bottom of trench, trench backfilled on 05-30-02 8 MAJOR DIVISIONS SYMBOL DESCRIPTION Gw WELL GRADED GRAVELS OR GRAVEL-SAND MIXTURES,LITTLE OR NO FINES GRAVELS GP (MORE THAN 'A POORLY GRADED GRAVELS OR GRAVEL-SAND OF COARSE MIXTURES,LITTLE OR NO FINES FRACTION GNI >NO.4 SIEVE SILTY GRAVELS,GRAVEL-SAND-SILT MIXTURES COARSE SIZE) GC GRAINED SOILS CLAYEY GRAVELS,GRAVEL-SAND-CLAY MIXTURES (MORE THAN %OF SOIL> Sw NO.200 SIEVE SIZE) WELL GRADED SANDS OR GRAVELLY SANDS, LITTLE OR NO FINES SANDS SP (MORE THAN '/: POORLY GRADED SANDS OR GRAVELLY SANDS, OF COARSE LITTLE OR NO FINES FRACTION S1I <NO.4 SIEVE SILTY SANDS,SILT-SAND MIXTURES SIZE) SC CLAYEY SANDS,SAND-CLAY MIXTURES NIL INORGANIC SILTS AND VERY FINE SANDS,ROCK FLOUR,SILTY OR CLAYEY FINE SANDS OR CLAYEY SILTS & SILTS WITH SLIGHT PLASTICITY CLAYS CL INORGANIC CLAYS OF LOW TO MEDIUM LIQUID LIMIT PLASTICITY,GRAVELLY CLAYS,SANDY CLAYS, <50 SILTY CLAYS,LEAN CLAYS FINE GRAINED OL ORGANIC SILTS AND ORGANIC SILTY CLAYS OF SOILS LOW PLASTICITY (MORE THAN ''A OF SOIL< NO.200 SIEVE SIZE) MH INORGANIC SILTS,MICACEOUS OR DIATOMACEOUS SILTS & FINE SANDY OR SILTY SOILS,ELASTIC SILTS CLAYS CH LIQUID LIMIT INORGANIC CLAYS OF HIGH PLASTICITY,FAT 50 CLAYS OH ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY, ORGANIC SILTY CLAYS,ORGANIC SILTS HIGHLY ORGANIC SOILS Pt PEAT AND OTHER HIGHLY ORGANIC SOILS CLASSIFICATION CHART (UNIFIED SOIL CLASSIFICATION SYSTEM) CLASSIFICATION RANGE OF GRAIN SIZES U.S.STANDARD I GRAIN SIZE IN K SIEVE SIZE MILLINIETERS ac BOULDERS Above 12 Inches I Above 305 COBBLES 1 12 Inches To 3 Inches 1 305 To 76.2 GRAVEL 3 Inches to No.4 76.2 to 4.76 = s° Coarse 3 Inches to'/.Inch I 76.2 to 19 1 = I I c l Fine '/.Inch to No.4 19.1 to 4.76 SAND No.4 to No.200 4.76 to 0.074 Coarse No.4 to No. 10 4.76 to 2.00 ,o Medium No. 10 to No.40 2.00 to 0.420 uicL=T'inw 1 �uc� Fine No.40 to No.200 0.420 to 0.074 ° a ila zo io .a w a° �o a° s° �°o SILT AND CLAY I Below No.200 I Below 0.074 uouto uwr (ti). GRAIN SIZE CHART PLASTICITY CHART EAST COUNTY SOIL CONSULTATION AND ENGINEERING, INC. 10925 HARTLEY ROAD, SUITE "I" BROWN PROJECT SANTEE, CALIFORNIA 92071 PROJECT NO. 02-1148B3 PLATE NO. 4 U.S.C.S. SOIL CLASSIFICATION GUNNESS PROJECT NO. 02-1148B3 PAGE L-1 LABORATORY TEST RESULTS RESULTS OF MAXIMUM DRY DENSITY AND OPTIMUM MOISTURE (ASTM D1557) The maximum dry densities and optimum moisture contents of the fill materials as determined by ASTM D1557-91, Procedure A and B which uses 25 blows of a 10 pound slide hammer falling from a height of 18 inches on each of 5 equal layers in a 4 inch diameter 1/30 cubic foot compaction cylinder and Procedure C which uses 56 blows of a 10 pound slide hammer falling from a height of 18 inches on each of 5 equal layers in a 6 inch diameter 1/13.3 cubic foot compaction cylinder are presented as follows: OPTIMUM MAXIMUM MOISTURE DRY DENSITY CONTENT SOIL TYPE/PROCEDURE LB/CU. FT. % DRY WT. TRENCH NO. 1 @ 1.0' 1/A GRAY BROWN, CLAYEY SAND 125.9 11.0 RESULTS OF EXPANSION INDEX TEST (UBC 18-2) An expansion test in conformance with UBC 18-2 was performed on a representative sample of on- site soils to determine volumetric change characteristics with change in moisture content. The recorded expansion of the sample is presented as follows: INITIAL SATURATED INITIAL DRY MOISTURE MOISTURE DENSITY EXPANSION CONTENT% CONTENT% LB./CU. FT. INDEX LOCATION 9.0 23.0 114.2 02 TRENCH 1 @ 1.0' 13.6 26.3 99.1 50 TRENCH 3 @ 2.0' 9 GUNNESS PROJECT NO. 02-1148B3 PAGE L-2 RESULTS OF PARTICLE SIZE ANALYSIS (ASTM D-422) U.S. Standard Percent Passing Percent Passing Percent Passing Sieve Size Trench No. 1 Trench No.3 Trench No. 3 (ASTM D-422) @ 1.0' @ 2.0' @ 3.0' 1" 100 100 100 '/" 100 100 100 3/8" 100 100 100 #4 97 100 96 #8 92 99 90 #16 85 97 84 #30 78 94 78 460 64 81 67 4100 56 71 61 4200 48 62 56 USCS Sc CL CL 10 SYMBOL LOCATION DEPTH LL W PL (°6) PI W U.S.C.S. (ft) (Entire Sample) 70 I it I i 60 I I I I I e. o I 30 CL ! N 1 Q � J ZD MH&OH I I 10 � I ,iIIIC�-ti1C..iillllt' MLs�'_ I � 0 � 0 '0 2C 3C 40 50 5C 70 80 90 100 PERFORMED IN GENERAL ACCORDANCE WITH, ASTM D4313-93 EAST COUNTY SOIL CONSULTATION AND ATTERBERG LIMITS TEST RESULTS ENGINEERING INC. L BROWN PROJECT 10925 Hartley Road, Suite I PROJECT NO. 02-1148B3 Santee, California 92071 PAGE L-3 PROJECT NO. DATE FIGURE 02-1148B3 11-03-02 GUNNESS PROJECT NO. 02-1148B3 REFERENCES 1. "1997 Edition of the Uniform Building Code, Volume 2, Chapter 16, Division IV", Published by International Conference of Building Officials. 2. "Maps of Known Active Fault Near-Source Zones in California and Adjacent Portions of Nevada", Page 0-36, used with the 1997 Edition of the Uniform Building Code, Published by International Conference of Building Officials. 3. "Landslide Hazards in the Rancho Sante Fe Quadrangle, San Diego County, California", Landslide Hazard Identification Map No. 6, by Siang S. Tan, Geologist, 1986. 11 EAST COUNTY SOIL CONSULTATION AND ENGINEERING, INC. 10925 HARTLEY ROAD, SUITE I SANTEE, CALIFOIUNIA 92071 (619) 258-7901 APPENDIX A RECOMMENDED EARTHWORK SPECIFICATIONS 1. General Description The intent of these specifications is to obtain uniformity and adequate strength in filled ground so that the proposed structures may be safely supported. The procedures include the clearing and preparation of the land to be filled, processing the fill soils, the spreading, and compaction of the filled areas to conform with the lines and grades as shown on the approved plans. The owner shall retain a Civil Engineer qualified in soil mechanics (herein referred to as engineer) to inspect and test earthwork in accordance with these specifications. The engineer shall advise the owvner and grading contractor immediately if any unsatisfactory conditions are observed to exist and shall have the authority to reject the compacted filled ground until such time that corrective measures are taken, necessary to comply with the specifications. It shall be the sole responsibility of the grading contractor to achieve the specified degree of compaction: 2. Preparing Areas to be Filled (a) All brush, vegetation and any biodegradable refuse shall be removed or otherwise disposed of so as to leave the areas to be filled free of vegetation and debris. Any uncompacted filled ground or loose compressible natural ground shall be removed unless the report recommends otherwise. Any buried tanks or other structures shall be removed and the depression backfilled to the satisfaction of the engineer. (b) The natural ground which is determined to be satisfactory for the support of the filled ground shall then be plowed or scarified to a depth of at least 12 inches (12"). (c) After the natural ground has been prepared. it shall then be brought to the proper moisture content and compacted to not less than 90 percent of maximum dry density in accordance with ASTM D 15 5 7-91. (d) Where fills are made on slopes greater than 20 percent, horizontal benches shall be cut into the firm natural ground. The initial bench at the toe of the fill shall be at least 15 feet in width on firm undisturbed natural ground. The width of all succeeding benches shall be at least 6 feet. APPENDIX A 2 J. Fill Materials All material shall be approved by the engineer and shall consist of materials free from vegetable matter, and other lumps greater than 6 inches in diameter. If, during grading operations, soils are found which were not encountered and tested in the preliminary investigation, tests on these soils shall be performed to determine their physical characteristics. Any special treatment recommended in the preliminary or subsequent soils reports not covered herein shall become an addendum to these specifications. 4. Placing and Compacting Fill Materials (a) When the moisture content of the fill material is below that specified, water shall be added until the moisture content is near optimum to assure uniform mixing and effective compaction. (b) When the moisture content of the fill materials is above that specified, the fill material shall be aerated by blading and scarifying or other satisfactory methods until the moisture content is near optimum as specified. (c) After processing, the suitable fill materials shall be placed in layers which, when compacted, shall not exceed six inches (6"). Each laver shall be spread evenly and shall be thoroughly mixed during the spreading insure uniformity of materials and moisture in each layer. (d) After each laver has been placed, mixed and spread evenly, it shall be thoroughly compacted to not less than the density set forth in paragraph 2 (c) above. Compaction shall be accomplished with approval types of compaction equipment. Rolling shall be accomplished while the fill material is at the specified moisture content. In place density tests shall be performed in accordance with ASTM D 1556-90. (e) The surfaces of the fill slopes shall be compacted by means of sheepsfoot rollers or other suitable equipment. Compacting operations shall be continued until the slopes are stable and until there is no appreciable amount of loose soil on the slopes. 5. Inspection Sufficient inspection by our firm or the Soil's Engineer of record and/or his/her representative shall be maintained during the filling and compacting operations so that he/she can verify that the fill was constructed in accordance with the accepted specifications. 6. Seasonal Limits No fill material shall be placed, spread, or rolled if weather conditions increase the moisture content above permissible limits. When the work is interrupted by rain, fill operations shall not be resumed until the moisture content and density of fill are as previously specified. All recommendations presented in the attached report are a part of these specifications. EAST COUNTY SOIL CONSULTATION AND ENGINEERING, INC. 10925 Hartley Road,Suite I _ Santee, California 92071 J31" (619)258-7901 Fax 258-7902 October 17, 2002 �J !1 SAN 2 'Paul & Kathy Mo eb i u s ENG EIkING 3911 Corte Mar De Brisa r pr ENCiNiT San Diego, California 92130 Subject : Project No. 02-1148B3 Limited Site Investigation Proposed Single Family Residence Megan Lane APN 164 "^ City of Encinitas, California Dear Mr. Brown: In accordance with your request, we have performed a limited investigation of the soil conditions at the subject site. The investigation was undertaken to provide the soil engineering criteria and recommend an appropriate foundation system for the proposed residential development. Our investigation found that the site is underlain by topsoil and colluvium to a depth of approximately 2 . 0 feet within the limits of the proposed construction. Dense rocks of the Santiago Peak Volcanics were underlying the colluvial soils . It is our opinion that the construction of the proposed residence is feasible provided the recommendations herein are implemented during construction. Respectfully submitted, Mamadou Saliou Diallo, P. E. RCE 54071 MSD/jm MOEBIUS PROJECT NO. 02-1148B3 INTRODUCTION This is to present the findings and conclusions of a soil investigation for the proposed single family residence to be located on the west side of Megan Lane, in the City of Encinitas, California . The objectives of the investigation were to evaluate the existing soils conditions and provide recommendations for the proposed construction. In order to accomplish these objectives, four exploratory trenches were excavated to a maximum depth of 4 . 5 feet; undisturbed and loose bag samples were obtained, and laboratory tests were performed. SITE DESCRIPTION AND PROPOSED CONSTRUCTION The subject site is located on the west side of Megan Lane, in the City of Encinitas, California. The property slopes gradually to the southwest . A residential development was observed to the east and south, and a vacant land to the west . The proposed construction consists of a single-family residence. It is our understanding that the house will be one-story and founded on continuous footings with a slab-on-grade floor. FIELD INVESTIGATION On May 30, 2002, four exploratory trenches were excavated to a depth of approximately 4 . 5 feet with a John Deere backhoe. The approximate locations of the trenches are shown on the attached Plate No. 1, entitled "Location of Exploratory Trenches" . A continuous log of the soils encountered was recorded at the time of excavation and is shown on the attached Plates No. 2 and 3 entitled "Summary Sheet" . The soils were visually and texturally classified according to the filed identification procedures set forth on the attached Plate No. 4 entitled "Uniform Soil Classification Chart" . SUBGRADE CONDITIONS Topsoil and colluvium were encountered to a depth of approximately 2 . 0 feet . The topsoil extending to a maximum depth of one foot consisted of loose silty sand with rootlets. The colluvium was 2 MOEBIUS PROJECT NO. 02-1148B3 made of sandy clay/clayey sand with a soft/loose consistency. Dense rocks of the Santiago Peak Volcanics were underlying the colluvium. EXPANSIVE SOILS Expansion index tests were performed on select samples of the colluvium to determine volumetric change characteristics with change in moisture content. Expansion indexes of 2 and 50 were obtained indicating a very low to low potential for expansion. GROUNDWATER No groundwater was encountered during the course of our investigation. The site is approximately 400 feet above mean sea level . We do not expect groundwater to affect the proposed development . However, oversaturated ground conditions at shallow depths may develop due to heavy precipitations, landscape watering, leaking water lines or unforeseen causes. Mitigative measures are discussed in the drainage section of this report . GEOLOGIC HAZARDS A review of the available geological literature pertaining to the site indicates the existence of the Rose Canyon Fault Zone approximately 12 Km to the west . Ground shaking from this fault or one of the major active faults in the region is the most likely happening to affect the site. With respect to this hazard, the site is comparable to others in the general area. The proposed residence should be designed in accordance with seismic design requirements of the 1997 Uniform Building Code or the Structural Engineers Association of California using the following seismic design parameters : PARAMETER VALUE UBC REFERENCE Seismic Zone Factor, Z 0.40 Table 16-I Soil Profile Type Sp Table 16-J Seismic Coefficient, Ca 0.44 Table 16-Q Seismic Coefficient, Cv 0.64 Table 16-R Near-Source Factor, Na 1.0 Table 16-S Near-Source Factor,Nv 1.0 Table 16-T Seismic Source B Table 16-U Based on the absence of shallow groundwater, type and consistency of the bedrock materials (Santiago Peak Volcanics) , it is our opinion that the potential for liquefaction is very low. 3 MOEBIUS PROJECT NO. 02-1148B3 CONCLUSION AND RECOMMEENDATIONS The following conclusions and recommendations are based upon the analysis of the data and information obtained from our soil investigation. This includes visual inspection; field investigation; laboratory testing and our general knowledge of the soils native to the site. The site is suitable for the proposed development provided the recommendations set forth are implemented during construction. GRADING AND EARTHWORK Site grading should begin with clearing and grubbing, e.g. the removal of brush, vegetation and topsoil. All colluvium under the house pad should be removed and recompacted to a minimum of 90 percent relative compaction while maintaining a moisture content 2 to 3 percent over optimum. The grading plan prepared by Logan Engineering indicates a transition between cut and fill on the house pad. Therefore, to minimize differential settlement, we recommend a minimum of 3 feet of a fill blanket on the house pad. The overexcavation should extend at least 5 feet beyond perimeter footings . Heavy ripping and/or blasting may be required. The fill soils should be moisture conditioned 2 to 3 percent over optimum, placed in thin lifts and compacted to a minimum of 90 percent relative compaction. The actual depth and extent of removal should be evaluated in the field at the time of excavation by a representative of this firm. Grading should be done in accordance with the attached Appendix A. An alternative to the overexcavation and recompaction process is to extend the footings to the Santiago Peak Volcanics . FOUNDATION AND SLAB a. Conventional continuous and spread footings are suitable for the proposed house. Continuous footings should extend a minimum of 12 inches for the one-story structure into the compacted fill soil or the Santiago Peak Volcanics . The footings should be at least 12 inches in width and reinforced with two #5 steel bars; one bar placed near the top of the footings and the other bar placed near the bottom of the footings . b. Concrete floor slabs should be a minimum 4 inches thick. Reinforcement should consist of #3 bars placed at 18 inches on center each way. Slab reinforcement should be placed within the middle third of the slab by supporting the steel on chairs or concrete blocks "dobies" . The slab should be underlain by 2 inches 4 MOEBIUS PROJECT NO. 02-1148B3 of clean sand over a 10-mil visqueen moisture barrier. The effect of concrete shrinkage will result in cracks in virtually all concrete slabs. To reduce the extent of shrinkage, the concrete should be placed at a maximum of 4-inch slump. The minimum steel recommended is not intended to prevent shrinkage cracks. C. Where moisture sensitive floor coverings are anticipated over the slab, the 10-mil plastic moisture barrier should be underlain by a capillary break at least 4 inches thick, consisting of sand, gravel or 3/4 inch crushed rock with no more than 5 percent passing the No. 200 sieve. d. An allowable soil bearing value of 1500 pounds per square foot may be used for the design of continuous and spread footings founded a minimum of 12 inches into the compacted fill soils. This value may be increased by 20 percent for each additional foot of depth to a maximum value of 4500 lb/ft2 as set forth in the 1997 edition of the Uniform Building Code, Table No. 18-1-A. If footings are founded in competent bedrock (Santiago Peak Volcanics) an allowable soil bearing value of 2500 psf may be used. SETTLEMENT Settlement of compacted fill soils is normal and should be anticipated. Because of the minor thickness of the fill soils under the proposed footings, and the light building loads, settlement should be within acceptable limits . DRAINAGE Adequate measures shall be undertaken to properly drain the site after the structure and other improvements are in place, such that the drainage water within the site and adjacent properties is directed away from the foundations via surface swales and subsurface drains towards the natural drainage for this area . Proper surface and subsurface drainage will be required to minimize the potential of water seeking the level of the bearing soils under the foundations, which may otherwise result in undermining and differential settlement of the structure and other improvements . 5 MOEBIUS PROJECT NO. 02-1148B3 LIMITATIONS OF INVESTIGATION The recommendations in this report pertain only to the site investigated and based upon the assumption that the soil conditions do not deviate from those disclosed in the trenches. If any variations or undesirable conditions are encountered during construction, or if the proposed construction will significantly differ from that planned at the present time, East County Soil Consultation and Engineering, Inc. should be notified so that supplemental recommendations can be made. Plates No. 1 through 4, Pages L-1 through L-3, References and Appendix A are parts of this report . Respectfull ubmitted, rn y O t 1 sq CMv e,t_ r Mamadou Saliou Diallo, P.E. RCE 54071 MSD/jm 6 Q .rte Q EAST COUNTY SOIL CONSULTATION & ENGINEERING, INC. _ &! Q 10925 HARTLEY RD.,SUITE I,SANTEE.CA 92071 �(/� (619)258-7901 Fax(619)258-7902 MOEBIUS PROJECT NO. 02-1148B3 PLATE NO. 2 SUMMARY SHEET NO. 1 TRENCH NO. 1 DEPTH SOIL DESCRIPTION Y M Surface TOPSOIL medium brown, dry, loose, silty sand, rootlets 0. 6' COLLUVIUM (Qal) red brown, dry, loose 118 . 0 3. 8 clayey sand 2 . 0 SANTIAGO PEAK VOLCANICS (Jsp) gray brown, dense rocks 3 . 0' bottom of trench, refusal, trench backfilled 05-30-02 ---------------------------------------- TRENCH NO. 2 DEPTH SOIL DESCRIPTION Y M Surface TOPSOIL medium brown, dry, loose silty sand, rootlets 1 . 0' COLLUVIUM (Qal) red brown, moist, soft, sandy clay (CL) 9. 1 1 . 5' SANTIAGO PEAK VOLCANICS (Jsp) gray brown, dense rocks 2 . 5' bottom of trench, refusal, trench backfilled 05-30-02 ------------------------------------ 7 MOEBIUS PROJECT NO. 02-1148B3 PLATE NO. 3 SUMMARY SHEET NO. 1 TRENCH NO. 3 DEPTH SOIL DESCRIPTION y M Surface TOPSOIL medium brown, dry, loose, silty sand, rootlets 1 . 0' COLLUVIUM (Qal) medium brown, moist, medium dense clayey sand 2 . 0' gray brown, moist, stiff, 113 . 8 13. 6 sandy clay 3 . 0' gray brown, moist, stiff, 114 . 0 11 . 7 sandy clay 3. 5' SANTIAGO PEAK VOLCANICS (Jsp) gray brown, dense rocks 4 . 5' bottom of trench, trench backfilled on 05-30-02 TRENCH NO. 4 DEPTH SOIL DESCRIPTION y M Surface TOPSOIL medium brown, dry, loose, silty sand, rootlets 0. 5' COLLUVIUM (Qal) tan brown, dry, loose, clayey sand 1 . 5' SANTIAGO PEAK VOLCANICS (Jsp) gray brown, dense rocks 3 . 5' bottom of trench, trench backfilled on 05-30-02 8 MAJOR DIVISIONS SYMBOL DESCRIPTION GW WELL GRADED GRAVELS OR GRAVEL-SAND MIXTURES,LITTLE OR NO FINES GRAVELS GP (MORE THAN A� POORLY GRADED GRAVELS OR GRAVEL-SAND OF COARSE MIXTURES,LITTLE OR NO FINES FRACTION GM >NO.4 SIEVE SILTY GRAVELS,GRAVEL-SAND-SILT MIXTURES COARSE SIZE) GC GRAINED SOILS CLAYEY GRAVELS,GRAVEL-SAND-CLAY MIXTURES (MORE THAN%OF SOIL> Sw NO.200 SIEVE SIZE) WELL GRADED SANDS OR GRAVELLY SANDS, LITTLE OR NO FINES SANDS SP (MORE THAN`/a POORLY GRADED SANDS OR GRAVELLY SANDS, OF COARSE LITTLE OR NO FINES FRACTION SyI <NO.4 SIEVE SILTY SANDS,SILT-SAND MIXTURES SIZE) Sc CLAYEY SANDS,SAND-CLAY MIXTURES NIL INORGANIC SILTS AND VERY FINE SANDS,ROCK FLOUR,SILTY OR CLAYEY FINE SANDS OR CLAYEY SILTS & SILTS WITH SLIGHT PLASTICITY CLAYS CL INORGANIC CLAYS OF LOW TO MEDIUM LIQUID LIMIT PLASTICITY,GRAVELLY CLAYS,SANDY CLAYS, <50 SILTY CLAYS,LEAN CLAYS FINE GRAINED OL - SOILS ORGANIC SILTS ANDO RGCAMC SILTY CLAYS OF (MORE THAN%a OF SOIL< TIVIII NO.200 SIEVE SIZE) INORGANIC SILTS,MICACEOUS OR DIATOMACEOUS SILTS & FINE SANDY OR SILTY SOILS,ELASTIC SILTS CLAYS CH INORGANIC CLAYS OF HIGH PLASTICITY,FAT LIQUID LIMIT 50 CLAYS OH CLAYS CLAYS OF MEDIUM TO HIGH PLASTICITY, ORGANIC SILTY CLAYS,ORGANIC SILTS HIGHLY ORGANIC SOILS Pt PEAT AND OTHER HIGHLY ORGANIC SOILS CLASSIFICATION CHART(UNIFIED SOIL CLASSIFICATION SYSTEM) CLASSIFICATION RANGE OF GRAIN SIZES I I I U.S.STANDARD GRAIN SIZE IN x SIEVE SIZE MILLIMETERS BOULDERS Above 12 Inches Above 305 COBBLES I2 Inches To 3 Inches I 305 To 76.2 'O I I 1 GRAVEL I 3 Inches to No.4 76.2 to 4.16 ` Coarse 3 Inches to%Inch 763 to 19.1 Fine a/.Inch to No.4 19.1 to 4.76 ro I SAND No.4 to No.200 4.76 to 0.074 ' , ( t I 4Nat°YI Coarse No.4 to No. IO 4.76 to 2.00 i° 1 Medium No. 10 to No.40 2.00 to 0.420 _ I wsot Fine No.40 to No.200 0.420 to 0.074 ° o to m w .o so ao 70 ao so Ioo SILT AND CLAY I Below No.200 1 Below 0.074 uauIo uWC(ti). = GRAIN SIZE CHART PLASTICITY CHART EAST COUNTY SOIL CONSULTATION AND ENGINEERING, INC. 10925 HARTLEY ROAD,SUITE "I" BROWN PROJECT S�.NTEE, CALIFORNIA 93071 PROJECT N0. 02-1148B3 PLATE N0. 4 U.S.C.S. SOIL CLASSIFICATIO MOEBIUS PROJECT NO. 02-1148B3 PAGE L-1 LABORATORY TEST RESULTS RESULTS OF MAXIMUM DRY DENSITY AND OPTIMUM MOISTURE (ASTM D1557) The maximum dry densities and optimum moisture contents of the fill materials as determined by ASTM D1557-91, Procedure A and B which uses 25 blows of a 10 pound slide hammer falling from a height of 18 inches on each of 5 equal layers in a 4 inch diameter 1/30 cubic foot compaction cylinder and Procedure C which uses 56 blows of a 10 pound slide hammer falling from a height of 18 inches on each of 5 equal layers in a 6 inch diameter 1/13.3 cubic foot compaction cylinder are presented as follows: OPTIMUM MAXIMUM MOISTURE DRY DENSITY CONTENT SOIL TYPE/PROCEDURE LB/CU. FT. %DRY WT. TRENCH NO. 1 @ 1.0' 1/A GRAY BROWN, CLAYEY SAND 125.9 11.0 RESULTS OF EXPANSION INDEX TEST (UBC 18-2) An expansion test in conformance with UBC 18-2 was performed on a representative sample of on- site soils to determine volumetric change characteristics with change in moisture content. The recorded expansion of the sample is presented as follows: INITIAL SATURATED INITIAL DRY MOISTURE MOISTURE DENSITY EXPANSION CONTENT% CONTENT% LB./CU. FT. INDEX LOCATION 9.0 23.0 114.2 02 TRENCH 1 @ 1.0' 13.6 26.3 99.1 50 TRENCH 3 @ 2.0' 9 MOEBIUS PROJECT NO. 02-1148B3 PAGE L-2 RESULTS OF PARTICLE SIZE ANALYSIS (AST M D-422 U S Standard Percent Passing Percedfpassmg ::Percent Passing Sieve Size' 'Trench'No 1 Trench No ';L TrenchNa.3 (ASTM D-422) 1 . 2 0' , @ @, @ 3.0. 0' 1" 100 100 100 ''/z" 100 100 100 3/8" 100 100 100 #4 97 100 96 #8 92 99 90 #16 85 97 84 #30 78 94 78 #60 64 81 67 #100 56 71 61 #200 48 62 56 USCS SC CL CL 10 MOEBIUS PROJECT NO. 02-1148B3 REFERENCES 1. "1997 Edition of the Uniform Building Code, Volume 2, Chapter 16, Division IV", Published by International Conference of Building Officials. 2. "Maps of Known Active Fault Near-Source Zones in California and Adjacent Portions of Nevada", Page 0-36, used with the 1997 Edition of the Uniform Building Code, Published by International Conference of Building Officials. 3. "Landslide Hazards in the Rancho Sante Fe Quadrangle, San Diego County, California", Landslide Hazard Identification Map No. 6, by Siang S. Tan, Geologist, 1986. 11 EAST COUNTY SOIL CONSULTATION AND ENGINEERING,INC. 10925 HARTLEY ROAD,SUITE I SANTEE, CALIFORNIA 92071 (619)258-7901 APPENDIX A RECOMMENDED EARTHWORK SPECIFICATIONS 1. General Description The intent of these specifications is to obtain uniformity and adequate strength in filled ground so that the proposed structures may be safely supported. The procedures include the clearing and preparation of the land to be filled, processing the fill soils, the spreading, and compaction of the filled areas to conform with the lines and grades as shown on the approved plans. The owner shall retain a Civil Engineer qualified in soil mechanics (herein referred to as engineer) to inspect and test earthwork in accordance with these specifications. The engineer shall advise the owner and grading contractor immediately if any unsatisfactory conditions are observed to exist and shall have the authority to reject the compacted filled ground until such time that corrective measures are taken, necessary to comply with the specifications. It shall be the sole responsibility of the grading contractor to achieve the specified degree of compaction. 2. Preparing Areas to be Filled (a) All brush, vegetation and any biodegradable refuse shall be removed or otherwise disposed of so as to leave the areas to be filled free of vegetation and debris. Any uncompacted filled ground or loose compressible natural ground shall be removed unless the report recommends otherwise. Any buried tanks or other structures shall be removed and the depression backfilled to the satisfaction of the engineer. (b) The natural ground which is determined to be satisfactory for the support of the filled ground shall then be plowed or scarified to a depth of at least 12 inches (12"). (c) After the natural ground has been prepared, it shall then be brought to the proper moisture content and compacted to not less than 90 percent of maximum dry density in accordance with ASTM D 1557-91. (d) Where fills are made on slopes greater than 20 percent, horizontal benches shall be cut into the firm natural ground. The initial bench at the toe of the fill shall be at least 15 feet in width on firm undisturbed natural ground. The width of all succeeding benches shall be at least 6 feet. APPENDIX A 2 3. Fill Materials All material shall be approved by the engineer and shall consist of materials free from vegetable matter, and other lumps greater than 6 inches in diameter. If, during grading operations, soils are found which were not encountered and tested in the preliminary investigation, tests on these soils shall be performed to determine their physical characteristics. Any special treatment recommended in the preliminary or subsequent soils reports not covered herein shall become an addendum to these specifications. 4. Placing and Compacting Fill Materials (a) When the moisture content of the fill material is below that specified, water shall be added until the moisture content is near optimum to assure uniform mixing and effective compaction. (b) When the moisture content of the fill materials is above that specified, the fill material shall be aerated by blading and scarifying or other satisfactory methods until the moisture content is near optimum as specified. (c) After processing, the suitable fill materials shall be placed in layers which, when compacted, shall not exceed six inches (6"). Each layer shall be spread evenly and shall be thoroughly mixed during the spreading insure uniformity of materials and moisture in each layer. (d) After each layer has been placed, mixed and spread evenly, it shall be thoroughly compacted to not less than the density set forth in paragraph 2 (c) above. Compaction shall be accomplished with approval types of compaction equipment. Rolling shall be accomplished while the fill material is at the specified moisture content. In place density tests shall be performed in accordance with ASTM D1556-90. (e) The surfaces of the fill slopes shall be compacted by means of sheepsfoot rollers or other suitable equipment. Compacting operations shall be continued until the slopes are stable and until there is no appreciable amount of loose soil on the slopes. 5. Inspection Sufficient inspection by our firm or the Soil's Engineer of record and/or his/her representative shall be maintained during the filling and compacting operations so that he/she can verify that the fill was constructed in accordance with the accepted specifications. 6. Seasonal Limits No fill material shall be placed, spread, or rolled if weather conditions increase the moisture content above permissible limits. When the work is interrupted by rain, fill operations shall not be resumed until the moisture content and density of fill are as previously specified. All recommendations presented in the attached report are a part of these specifications.