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2004-9183 G City of'ENGINEERING SERVICES DEPARTMENT Eminitas Capital Improvement Projects District Support Services Field Operations Sand Replenishment/Stormwater Compliance Subdivision Engineering Traffic Engineering March 23, 2006 Attn: Insurance Company of the West 11455 El Camino Real San Diego, California 92130 RE: Grace Partners, LLC 700-720 Garden View APN 257-470-04,05 Grading Permit 9183-G Final release of security Permit 9183-G authorized earthwork, storm drainage, single driveway, and erosion control, all needed to build the described project. The Field Operations Division has approved the grading and finaled the project. Therefore, a release in the remaining security deposit is merited. Performance Bond 213 67 77, in the original amount of$242,700.00, (reduced by 75% to $60,675.00 on May 26, 2005), may be released in entirety. 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. Sincerel , Debra Geisha JJay Lembach Engineering Technician Finance Manager Subdivision Engineering Financial Services CC Jay Lembach,Finance Manager Grace Partners,LLC Debra Geishart File Enc. TEL 760-633-2600 / FAX 760-633-2627 505 S. Vulcan Avenue, Encinitas, California 92024-3633 TDD 760-633-2700 q0 recycled paper K&S ENGINEERING s Planning Engineering Surveying N1 51113 /r Z NVP HYDROLOGICAL ANALYSIS FOR GARDEN VIEW OFFICE LOTS 4 & 5 OF ENCINITAS TRACT NO. 4255 IN CITY OF ENCINITAS OQROFESS/�N S. c No.48592 m - JN 04-118 November 24, 2004. ! Z o �l L AL S. S IS .C.E. 48591 DATt 7801 Mission Center Court, Suite 100 • San Diego, California 92108 • (619) 296-5565 • Fax (619) 296 5564 TABLE OF CONTENTS 1. INTRODUCTION 2. HYDROLOGY DESIGN MODELS 3. HYDROLOGIC CALCULATIONS .......................... APPENDIX A 4. TABLES AND CHARTS ....................................... APPENDIX B 5. HYDROLOGY MAPS ............................................ APPENDIX C 6. BIO-SWALE NUMERIC SIZING.......................... APPENDIX D 1. INTRODUCTION A. THE EXISTING CONDITION THE EXISTING SITE CONSISTS OF TWO VACANT LOTS PREVIUSLY GRADED (LOTS 4 & 5 OF ENCINITAS TRACT 4255.) THE TOTAL EXISTING DRAINAGE AREA IS 2.32 ACRES. _ CURRENTLY 2.01 ACRES SHEET-FLOW TOWARDS AN EXISTING DESILTING BASIN LOCATED ON THE SOUTHEAST CORNER OF LOT 4, GENERATING 3.47 C.F.S. THE REST OF THE SITE DRAINS TOWARDS TWO POINTS. A TRIBUTARY AREA OF 0.24 ACRES DRAINS TOWARDS THE WEST GENERATING 0.60 C.F.S.. THE SECOND POINT DRAINS TOWARDS GARDEN VIEW ROAD WITH A Q100= 0.17 C.F.S. B. PROPOSED CONDITION THE PROPOSED DEVELOPMENT CONSISTS OF THE CONSTRUCTION OF ONE OFFICE BUILDING WITH ASSOCIATED PARKING LOT. STORM RUNOFF WILL BE COLLECTED _ USING PRIVATE INLETS AND CONVEYED USING PRIVATE STORM DRAIN PIPES. 1.96 ACRES OF TRIBUTARY AREA WILL DRAIN TOWARDS A PROPOSED BIO-SWALE ON THE SOUTHEAST SIDE OF THE SITE FOR WATER QUALITY PURPOSES, THEN THE RUN-OFF WILL BE CONVEYED TO THE EXISTING STORM DRAIN MANHOLE ON GARDEN VIEW ROAD. THE RUNOFF FROM THE PROPOSED CONDITION AT THIS POINT IS 8.9 C.F.S. THE EXISTING 24" R.C.P. HAS THE CAPACITY TO HANDLE THE PROPOSED RUNOFF AS SHOWN ON CALCULATION. THE 0.32 ACRE EAST SIDE OF THE SITE KEPT THE UNDEVELOPED DRAINAGE PATTERN GENERATING 1.86 C.F.S. 0.4 ACRES OF THE WESTERLY SIDE OF THE SITE WILL DRAIN TOWARDS GARDEN VIEW COURT GENERATING 0.24 C.F.S. ALL THE RUNOFF FROM THE PAVED AREA WILL BE TREATED. - C. SUMMARY THE INCREASED RUNOFF FROM THE EXISTING CONDITION TO THE PROPOSED _ CONDITION IS DUE SOLELY TO INCREASING THE "C" VALUE FROM MULTI-UNIT DEVELOPMENT (C=0.35) TO COMMERCIAL DEVELOPMENT (C=0.85). THE EXISTING IMPROVEMENTS WERE DESIGN TO HANDLE THE ULTIMATE FLOW USING THE "C" VALUE FOR THE PROPOSED ZONING. THEREFORE THE STRUCTURES DOWNSTREAM WILL NOT HAVE ANY NEGATIVE IMPACTS. THE PROPOSED BIO-SWALE WILL HAVE THE CAPACITY TO TREAT THE RUN-OFF FROM _.. THE PAVED AREA. s _.e e a� .J 2. HYDROLOGY DESIGN MODELS A. DESIGN METHODS THE RATIONAL METHOD IS USED IN THIS HYDROLOGY STUDY; THE RATIONAL FORMULA IS AS FOLLOWS: Q=CIA,WHERE : Q=PEAK DISCHARGE IN CUBIC FEET/SECOND C=RUNOFF COEFFICIENT(DIMENSIONLESS) I=RAINFALL'INTENSITY IN INCHESMOUR A=TRIBUTARY DRAINAGE AREA IN ACRES *I ACRE INCHES/HOUR= 1.008 CUBIC FEET/SEC THE OVERLAND FLOW FORMULA IS AS FOLLOWS: Tc=I.8(1.1-C)*(L)5/(S*100)"" L=OVERLAND TRAVEL DISTANCE IN FEET S=SLOPE IN FT/FT Tc=TIME OF CONCENTRATION IN MINUTES B. DESIGN CRITERIA -FREQUENCY, 100 YEAR STORM. -LAND USE PER SPECIFIC PLAN AND TENTATIVE MAP. - RAIN FALL INTENSITY PER COUNTY OF SAN DIEGO 1993 HYDROLOGY DESIGN MANUAL. C. REFERENCES -COUNTY OF SAN DIEGO 2003,HYDROLOGY MANUAL. -COUNTY OF SAN DIEGO 1992 REGIONAL STANDARD DRAWING. -HAND BOOK OF HYDRAULICS BY BRATER&KING, SIXTH EDITION. 3. HYDROLOGIC CALCULATIONS EXISTING CONDITION HYDROLOGY J.N.04-118UND San Diego County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software,(c)1991-2003 Version 6.3 Rational method hydrology program based on San Diego County Flood Control Division 1985 hydrology manual Rational Hydrology Study Date: 10/04/04 ------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** ------------------------------------------------------------------------ K&S Engineering,San Diego,California-S/N 868 ------------------------------------------------------------------------ Rational hydrology study storm event year is 100.0 English(in-lb)input data Units used English(in)rainfall data used Map data precipitation entered: 6 hour, precipitation(inches)= 2.700 24 hour precipitation(inches)= 4.300 Adjusted 6 hour precipitation(inches)= 2.700 P61P24= 62.8% San Diego hydrology manual'C'values used Runoff coefficients by rational method ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++.. Process from Point/Station 1.000 to Point/Station 2.000 ****INITIAL AREA EVALUATION**** User specified'C'value of 0.350 given for subarea Initial subarea flow distance = 60.000(Ft.) Highest elevation= 185.000(Ft.) Lowest elevation= 182.750(Ft.) Elevation difference= 2.250(Ft.) Time of concentration calculated by the urban areas overland flow method(App X-C)= 6.73 min. TC=[1.8*(1.1-C)*distance(Ft.)1.5)/(%slope^(]/3)] TC=[1.8*(1.1-0.3500)*( 60.000^.5)/(3.750^(]/3)]= 6.73 Rainfall intensity(1)= 5.873(ln/Hr)fora 100.0 year storm Effective runoff coefficient used for area(Q=KCIA)is C=0.350 ° Subarea runoff= 0.185(CFS) Total initial stream area= 0.090(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 2.000 to Point/Station 3.000 ****IMPROVED CHANNEL TRAVEL TIME **** Upstream point elevation= 182.750(Ft.) Downstream point elevation= 162.000(Ft.) Channel length thru subarea = 322.000(Ft.) Channel base width= 0.000(Ft.) Slope or'Z'of left channel bank= 100.000 Slope or'Z'of right channel bank= 100.000 Estimated mean flow rate at midpoint of channel= 2.158(CFS) Manning's'N' =0.020 Maximum depth of channel = 0.500(Ft.) Flow(q)thru subarea= 2.158(CFS) m Depth of flow= 0.094(Ft.),Average velocity= 2.453(Ft/s) _.. Channel flow top width= 18.760(Ft.) Flow Velocity= 2.45(Ft/s) ,.d Travel time = 2.19 min. Time of concentration= 8.92 min. Critical depth= 0.124(Ft.) Adding area flow to channel User specified'C'value of 0.350 given for subarea Rainfall intensity= 4.898(In/Hr)fora 100.0 year storm Runoff coefficient used for sub-area,Rational method,Q=KCIA,C=0.350 Subarea runoff= 3.291(CFS)for 1.920(Ac.) Total runoff= 3.476(CFS)Total area= 2.01(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.000 to Point/Station 4.000 ****INITIAL AREA EVALUATION **** User specified'C'value of 0.350 given for subarea Initial subarea flow distance = I00.000(Ft.) Highest elevation= 185.000(Ft.) Lowest elevation= 160.000(Ft.) Elevation difference= 25.000(Ft.) Time of concentration calculated by the urban areas overland flow method(App X-C)= 4.62 min. TC=[1.8*(1.1-C)*distance(Ft.)^.5)/(%slope^(1/3)] TC=[1.8*(1.1-0.3500)*( 100.000^.5)1( 25.000^(1/3)]= 4.62 Setting time of concentration to 5 minutes Rainfall intensity(I)= 7.114(In/Hr)fora 100.0 year storm Effective runoff coefficient used for area(Q=KCIA)is C=0.350 Subarea runoff= 0.598(CFS) Total initial stream area= 0.240(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 5.000 to Point/Station 6.000 ****INITIAL AREA EVALUATION **** User specified'C'value of 0.350 given for subarea Initial subarea flow distance = 34.000(Ft.) Highest elevation= 165.000(Ft.) Lowest elevation= 153.000(Ft.) Elevation difference= 12.000(Ft.) Time of concentration calculated by the urban areas overland flow method(App X-C)= 2.40 min. TC=[1.8*(1.1-C)*distance(Ft.)^.5)/(%slope^(1/3)] TC=[1.8*(1.1-0.3500)*( 34.000^.5)/( 35.294^(1/3)]= 2.40 Setting time of concentration to 5 minutes Rainfall intensity(1)= 7.114(In/Hr)fora 100.0 year storm Effective runoff coefficient used for area(Q=KCIA)is C=0.350 Subarea runoff= 0.174(CFS) Total initial stream area= 0.070(Ac.) End of computations,total study area= 2.320(Ac.) s r� PROPOSED CONDITION HYDROLOGY J.N.04-118DEV San Diego County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software,(c)1991-2003 Version 6.3 Rational method hydrology program based on San Diego County Flood Control Division 1985 hydrology manual - Rational Hydrology Study Date: 10/08/04 ------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** ------------------------------------------------------------------------ K&S Engineering,San Diego,California-S/N 868 ------------------------------------------------------------------------ Rational hydrology study storm event year is 100.0 English(in-lb)input data Units used English(in)rainfall data used Map data precipitation entered: 6 hour, precipitation(inches)= 2.700 24 hour precipitation(inches)= 4.300 Adjusted 6 hour precipitation(inches)= 2.700 P6/P24= 62.8% San Diego hydrology manual'C'values used Runoff coefficients by rational method ++++++++++++++++++... H++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.000 to Point/Station 2.000 ****INITIAL AREA EVALUATION **** User specified'C'value of 0.850 given for subarea Initial subarea flow distance = 60.000(Ft.) Highest elevation= 185.500(Ft.) Lowest elevation= 184.900(Ft.) Elevation difference= 0.600(Ft.) Time of concentration calculated by the urban areas overland flow method(App X-C)= 3.49 min. -- TC=[1.8*(1.1-C)*distance(Ft.)^.5)/(°/a slope^(1/3)] TC=[1.8*(I.1-0.8500)*( 60.000^.5)/( 1.000^(1/3)]= 3.49 Setting time of concentration to 5 minutes Rainfall intensity(1)= 7.114(In/Hr)fora 100.0 year storm Effective runoff coefficient used for area(Q=KCIA)is C=0.850 Subarea runoff= 0.079(CFS) Total initial stream area= 0.013(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 2.000 to Point/Station 3.000 ****IMPROVED CHANNEL TRAVEL TIME**** Upstream point elevation= 184.900(Ft.) Downstream point elevation= 184.150(Ft.) Channel length thru subarea = 77.300(Ft.) � Channel base width= 0.000(Ft.) Slope or'Z'of left channel bank= 66.670 Slope or'Z'of right channel bank= 66.670 Estimated mean flow rate at midpoint of channel= 0.175(CFS) Manning's'N' =0.020 Maximum depth of channel = 0.500(Ft.) Flow(q)thru subarea= 0.175(CFS) Depth of flow= 0.061(Ft.),Average velocity= 0.712(Ft/s) Channel flow top width= 8.102(Ft.) Flow Velocity= 0.71(Ft/s) Travel time = 1.81 min. Time of concentration= 6.81 min. Critical depth= 0.053(Ft.) Adding area flow to channel User specified'C'value of 0.850 given for subarea Rainfall intensity= 5.829(In/Hr)fora 100.0 year storm Runoff coefficient used for sub-area,Rational method,Q=KCIA,C=0.850 Subarea runoff''= 0.159(CFS)for 0.032(Ac.) Total runoff= 0.237(CFS)Total area= 0.04(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/station 3.000 to Point/station 4.000 ****PIPEFLOW TRAVEL TIME(User specified size) **** Upstream point/station elevation= 173.380(Ft.) Downstream point/station elevation= 172.830(Ft.) Pipe length = 55.19(Ft.) Manning's N=0.013 No.of pipes= 1 Required pipe flow = 0.237(CFS) Given pipe size= 6.00(In.) Calculated individual pipe flow = 0.237(CFS) Normal flow depth in pipe= 2.72(ln.) Flow top width inside pipe= 5.97(ln.) Critical Depth= 2.94(ln.) Pipe flow velocity= 2.73(Ft/s) Travel time through pipe= 0.34 min. Time of concentration(TC)= 7.14 min. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/station 3.000 to Point/station 4.000 ****SUBAREA FLOW ADDITION **** User specified'C'value of 0.850 given for subarea Time of concentration= 7.14 min. Rainfall intensity= 5.651(ln/Hr)fora 100.0 year storm Runoff coefficient used for sub-area,Rational method,Q=KCIA,C=0.850 Subarea runoff= 1.009(CFS)for 0.210(Ac.) Total runoff= 1.246(CFS)Total area= 0.26(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/station 3.000 to Point/station 4.000 ****CONFLUENCE OF MINOR STREAMS **** Along Main Stream number: 1 in normal stream number I Stream flow area= 0.255(Ac.) Runoff from this stream= 1.246(CFS) Time of concentration= 7.14 min. Rainfall intensity= 5.651(1n/Hr) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 5.000 to Point/Station 6.000 ****INITIAL AREA EVALUATION **** User specified'C'value of 0.850 given for subarea Initial subarea flow distance = 89.000(Ft.) Highest elevation= 175.500(Ft.) Lowest elevation= 174.770(Ft.) Elevation difference= 0.730(Ft.) Time of concentration calculated by the urban areas overland flow method(App X-C)= 4.54 min. -- TC=[1.8-(1.1-Q-distance(Ft.)'.5)/(`/`slope^(1/3)] TC=[1.8*(1.I-0.8500)*( 89.000^.5)/( 0.820^(1/3)]= 4.54 Setting time of concentration to 5 minutes Rainfall intensity(1)= 7.114(ln/Hr)fora 100.0 year storm — Effective runoff coefficient used for area(Q=KCIA)is C=0.850 Subarea runoff= 0.847(CFS) Total initial stream area= 0.140(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 6.000 to Point/Station 4.000 ****PIPEFLOW TRAVEL TIME(User specified size)**** Upstream point/station elevation= 173.230(Ft.) Downstream point/station elevation= 172.830(Ft.) Pipe length = 17.17(Ft.) Manning's N=0.013 No.of pipes= 1 Required pipe flow = 0.847(CFS) Given pipe size= 6.00(ln.) Calculated individual pipe flow = 0.847(CFS) Normal flow depth in pipe= 4.85(In.) Flow top width inside pipe= 4.72(ln.) Critical Depth= 5.43(In.) Pipe flow velocity= 4.97(Ft/s) Travel time through pipe= 0.06 min. Time of concentration(TC)= 5.06 min. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/station 6.000 to Point/Station 4.000 ****CONFLUENCE OF MINOR STREAMS **** Along Main Stream number: 1 in normal stream number 2 Stream flow area= 0.140(Ac.) Runoff from this stream= 0.847(CFS) Time of concentration= 5.06 min. Rainfall intensity= 7.061(In/Hr) Summary of stream data: Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr) 1 1.246 7.14 5.651 - 2 0.847 5.06 7.061 Qmax(I)_ 1.000* 1.000* 1.246)+ 0.800* 1.000* 0.847)+= 1.923 Qmax(2)_ 1.000* 0.708 * 1.246)+ 1.000* 1.000* 0.847)+= 1.728 Total of 2 streams to confluence: Flow rates before confluence point: 1.246 0.847 Maximum flow rates at confluence using above data: 1.923 1.728 Area of streams before confluence: 0.255 0.140 Results of confluence: Total flow rate= 1.923(CFS) Time of concentration= 7.145 min. Effective stream area after confluence= 0.395(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 4.000 to Point/Station 7.000 ****PIPEFLOW TRAVEL TIME(User specified size) **** Upstream point/station elevation= 172.830(Ft.) Downstream point/station elevation= 169.330(Ft.) Pipe length = 86.15(Ft.) Manning's N=0.013 No.of pipes= I Required pipe flow = 1.923(CFS) Given pipe size= 8.00(In.) Calculated individual pipe flow = 1.923(CFS) Normal flow depth in pipe= 5.36(In.) Flow top width inside pipe= 7.52(In.) Critical Depth= 7.44(In.) Pipe flow velocity= 7.73(Ft/s) Travel time through pipe= 0.19 min. Time of concentration(TC)= 7.33 min. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 4.000 to Point/Station 7.000 ****SUBAREA FLOW ADDITION **** User specified'C'value of 0.850 given for subarea Time of concentration= 7.33 min. Rainfall intensity= 5.558(In/Hr)fora 100.0 year storm Runoff coefficient used for sub-area,Rational method,Q=KCIA,C=0.850 Subarea runoff= 0.850(CFS)for 0.180(Ac.) Total runoff= 2.774(CFS)Total area 0.57(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 7.000 to Point/Station 8.000 ****PIPEFLOW TRAVEL TIME(User specified size) **** Upstream point/station elevation= 169.330(Ft.) Downstream point/station elevation= 164.490(Ft.) Pipe length = 207.00(Ft.) Manning's N=0.013 No.of pipes= 1 Required pipe flow = 2.774(CFS) Given pipe size= 10.00(ln.) Calculated individual pipe flow = 2.774(CFS) Normal flow depth in pipe= 6.94(In.) - Flow top width inside pipe= 9.22(ln.) Critical Depth= 8.77(In.) Pipe flow velocity= 6.86(Ft/s) Travel time through pipe= 0.50 min. Time of concentration(TC)= 7.83 min. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ` Process from Point/Station 7.000 to Point/Station 8.000 ****SUBAREA FLOW ADDITION **** User specified'C'value of 0.850 given for subarea Time of concentration= 7.83 min. Rainfall intensity= 5.325(In/Hr)fora 100.0 year storm Runoff coefficient used for sub-area,Rational method,Q=KCIA,C=0.850 Subarea runoff= 1.765(CFS)for 0.390(Ac.) Total runoff= 4.539(CFS)Total area= 0.96(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 8.000 to Point/Station 9.000 ****PIPEFLOW TRAVEL TIME(User specified size)**** Upstream point/station elevation= 164.490(Ft.) Downstream point/station elevation= 162.610(Ft.) Pipe length = 187.92(Ft.) Manning s N=0.013 No.of pipes= 1 Required pipe flow = 4.539(CFS) Given pipe size= 15.00(ln.) Calculated individual pipe flow = 4.539(CFS) Normal flow depth in pipe= 9.27(ln.) Flow top width inside pipe= 14.58(ln.) Critical Depth= 10.36(ln.) Pipe flow velocity= 5.70(Ft/s) Travel time through pipe= 0.55 min. Time of concentration(TC)= 8.38 min. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 8.000 to Point/Station 9.000 ****SUBAREA FLOW ADDITION **** User specified'C'value of 0.850 given for subarea Time of concentration= 8.38 min. Rainfall intensity= 5.098(In/Hr)fora 100.0 year storm Runoff coefficient used for sub-area,Rational method,Q=KCIA,C=0.850 Subarea runoff= 2.773(CFS)for 0.640(Ac.) Total runoff= 7.312(CFS)Total area= 1.61(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 9.000 to Point/Station 10.000 ****PIPEFLOW TRAVEL TIME(User specified size)**** Upstream point/station elevation= 162.610(Ft.) Downstream point/station elevation= 162.000(Ft.) Pipe length = 22.06(Ft.) Manning's N=0.013 No.of pipes= I Required pipe flow = 7.312(CFS) Given pipe size= 15.00(In.) Calculated individual pipe flow = 7.312(CFS) Normal flow depth in pipe= 9.08(In.) Flow top width inside pipe= 14.66(ln.) Critical Depth= 12.95(In.) — Pipe flow velocity= 9.42(Ft/s) Travel time through pipe= 0.04 min. Time of concentration(TC)= 8.42 min. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 9.000 to Point/Station 10.000 ****CONFLUENCE OF MINOR STREAMS **** Along Main Stream number: I in normal stream number 1 Stream flow area= 1.605(Ac.) Runoff from this stream= 7.312(CFS) Time of concentration= 8.42 min. Rainfall intensity= 5.082(ln/Hr) Process from Point/Station 11.000 to Point/Station 12.000 ****INITIAL AREA EVALUATION **** User specified'C'value of 0.850 given for subarea Initial subarea flow distance = 50.000(Ft.) Highest elevation= 174.840(Ft.) Lowest elevation= 174.340(Ft.) Elevation difference= 0.500(Ft.) Time of concentration calculated by the urban areas overland flow method(App X-C)= 3.18 min. TC=[1.8*(l.]-C)*distance(Ft.)^.5)/(%slope^(1/3)] TC=[1.8*(1.1-0.8500)*( 50.000^.5)/( 1.000^(1/3)]= 3.18 Setting time of concentration to 5 minutes Rainfall intensity(I)= 7.1 14(ln/Hr)fora 100.0 year storm Effective runoff coefficient used for area(Q=KCIA)is C=0.850 Subarea runoff= 0.605(CFS) Total initial stream area= 0.100(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 12.000 to Point/Station 13.000 **** IMPROVED CHANNEL TRAVEL TIME**** Upstream point elevation= 174.340(Ft.) Downstream point elevation= 173.430(Ft.) Channel length thru subarea = 93.000(Ft.) Channel base width= 0.000(Ft.) Slope or'Z'of left channel bank= 10.000 Slope or'Z'of right channel bank= 10.000 Estimated mean flow rate at midpoint of channel= 0.937(CFS) Manning s'N' =0.020 Maximum depth of channel = 0.500(Ft.) Flow(q)thru subarea= 0.937(CFS) _. Depth of flow= 0.232(Ft.),Average velocity= 1.742(Ft/s) Channel flow top width= 4.639(Ft.) Flow Velocity= 1.74(Ft/s) Travel time = 0.89 min. Time of concentration= 5.89 min. Critical depth= 0.223(Ft.) Adding area flow to channel User specified'C'value of 0.850 given for subarea — Rainfall intensity= 6.401(In/Hr)fora 100.0 year storm Runoff coefficient used for sub-area,Rational method,Q=KCIA,C=0.850 Subarea runoff= 0.598(CFS)for 0.110(Ac.) Total runoff= 1.203(CFS)Total area= 0.21(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 13.000 to Point/Station 10.000 ****PIPEFLOW TRAVEL TIME(User specified size)**** Upstream point/station elevation= 171.430(Ft.) Downstream point/station elevation= 164.310(Ft.) Pipe length = 87.84(Ft.) Manning's N=0.013 No.of pipes= 1 Required pipe flow = 1.203(CFS) Given pipe size= 8.00(ln.) Calculated individual pipe flow = 1.203(CFS) _ Normal flow depth in pipe= 3.27(In.) Flow top width inside pipe= 7.86(ln.) Critical Depth= 6.23(In.) Pipe flow velocity= 8.98(Ft/s) Travel time through pipe= 0.16 min. Time of concentration(TC)= 6.05 min. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 13.000 to Point/Station 10.000 ****CONFLUENCE OF MINOR STREAMS**** Along Main Stream number: 1 in normal stream number 2 Stream flow area= 0.210(Ac.) Runoff from this stream= 1.203(CFS) Time of concentration= 6.05 min. Rainfall intensity= 6.289(ln/Hr) Summary of stream data: Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr) 1 7.312 8.42 5.082 2 1.203 6.05 6.289 Qmax(1)_ 1.000* 1.000* 7.312)+ 0.808 * 1.000* 1.203)+= 8.284 Qmax(2)_ 1.000* 0.719* 7.312)+ 1.000* 1.000* 1.203)+= 6.459 Total of 2 streams to confluence: Flow rates before confluence point: 7.312 1.203 Maximum flow rates at confluence using above data: 8.284 6.459 Area of streams before confluence: 1.605 0.210 Results of confluence: Total flow rate= 8.284(CFS) Time of concentration= 8.421 min. Effective stream area after confluence= 1.815(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 10.000 to Point/Station 14.000 ****IMPROVED CHANNEL TRAVEL TIME**** Upstream point elevation= 162.000(Ft.) Downstream point elevation= 153.000(Ft.) Channel length thru subarea = 220.680(Ft.) Channel base width= 0.000(Ft.) Slope or'Z'of left channel bank= 7.000 Slope or'Z'of right channel bank= 7.000 Estimated mean flow rate at midpoint of channel= 8.627(CFS) Manning's'N' =0.020 Maximum depth of channel = 0.500(Ft.) Flow(q)thru subarea= 8.627(CFS) Depth of flow= 0.467(Ft.),Average velocity= 5.651(Ft/s) Channel flow top width= 6.538(Ft.) Flow Velocity= 5.65(Ft/s) Travel time = 0.65 min. Time of concentration= 9.07 min. Critical depth= 0.609(Ft.) Adding area flow to channel User specified'C'value of 0.850 given for subarea e:_ Rainfall intensity= 4.844(ln/Hr)fora 100.0 year storm Runoff coefficient used for sub-area,Rational method,Q=KCIA,C=0.850 Subarea runoff= 0.618(CFS)for 0.150(Ac.) Total runoff= 8.902(CFS)Total area= 1.96(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 14.000 to Point/Station 15.000 ****PIPEFLOW TRAVEL TIME(User specified size)**** Upstream point/station elevation= 148.000(Ft.) Downstream point/station elevation= 139.430(Ft.) Pipe length = 29.34(Ft.) Manning's N=0.013 No.of pipes= 1 Required pipe flow = 8.902(CFS) Given pipe size= I8.00(ln.) Calculated individual pipe flow = 8.902(CFS) Normal flow depth in pipe= 4.82(ln.) Flow top width inside pipe= 15.94(In.) Critical Depth= 13.85(In.) Pipe flow velocity= 23.40(Ft/s) Travel time through pipe= 0.02 min. Time of concentration(TC)= 9.09 min. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 16.000 to Point/Station 17.000 ****INITIAL AREA EVALUATION**** User specified'C'value of 0.850 given for subarea Initial subarea flow distance = 90.000(Ft.) Highest elevation= 177.500(Ft.) Lowest elevation= 173.500(Ft.) Elevation difference= 4.000(Ft.) Time of concentration calculated by the urban areas overland flow method(App X-C)= 2.60 min. TC=[1.8*(1.I-C)*distance(Ft.)^.5)/(%slope^(1/3)] TC=[1.8*(l.l-0.8500)*( 90.000^.5)/( 4.444^(1/3)]= 2.60 - Setting time of concentration to 5 minutes Rainfall intensity(1)= 7.114(In/Hr)fora 100.0 year storm Effective runoff coefficient used for area(Q=KCIA)is C=0.850 Subarea runoff= 0.847(CFS) - Total initial stream area= 0.140(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 17.000 to Point/Station 18.000 ****IMPROVED CHANNEL TRAVEL TIME**** Upstream point elevation= 173.500(Ft.) Downstream point elevation= 161.000(Ft.) Channel length thru subarea = 111.000(Ft.) Channel base width= 0.000(Ft.) Slope or'Z'of left channel bank= 100.000 Slope or'Z'of right channel bank= 100.000 Estimated mean flow rate at midpoint of channel= 1.270(CFS) Manning's'N' =0.020 Maximum depth of channel = 0.500(Ft.) Flow(q)thru subarea= 1 270(CFS) Depth of flow= 0.069(Ft.),Average velocity= 2.648(Ft/s) Channel flow top width= 13.848(Ft.) Flow Velocity= 2.65(Ft/s) � Travel time = 0.70 min. Time of concentration= 5.70 min. Critical depth= 0.100(Ft.) w Adding area flow to channel User specified'C'value of 0.850 given for subarea Rainfall intensity= 6.538(ln/Hr)fora 100.0 year storm Runoff coefficient used for sub-area,Rational method,Q=KCIA,C=0.850 Subarea runoff= 0.778(CFS)for 0.140(Ac.) Total runoff= 1.625(CFS)Total area= 0.28(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 19.000 to Point/Station 20.000 **** INITIAL AREA EVALUATION **** User specified'C'value of 0.850 given for subarea Initial subarea flow distance = 120.000(Ft.) Highest elevation= '170.000(Ft.) Lowest elevation= 153.000(Ft.) Elevation difference= 17.000(Ft.) Time of concentration calculated by the urban areas overland flow method(App X-C)= 2.04 min. TC=[1.8*(].1-C)*distance(Ft.)'.5)/(`/`slope^(1/3)] TC=[1.8*(1.1-0.8500)*( 120.000^.5)/( 14.167^(1/3)]= 2.04 Setting time of concentration to 5 minutes Rainfall intensity(I)= 7.114(In/Hr)fora 100.0 year storm Effective runoff coefficient used for area(Q=KCIA)is C=0.850 Subarea runoff= 0.242(CFS) Total initial stream area= 0.040(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 21.000 to Point/Station 22.000 ****INITIAL AREA EVALUATION **** User specified'C'value of 0.850 given for subarea Initial subarea flow distance = 39.000(Ft.) Highest elevation= 170.940(Ft.) Lowest elevation= 169.030(Ft.) Elevation difference= 1.910(Ft.) Time of concentration calculated by the urban areas overland flow method(App X-C)= 1.65 min. - TC=[1.8*(1.1-C)*di stance(Ft.)^.5)/(%slope^(]/3)] TC=[1.8*(1.1-0.8500)*( 39.000^.5)/( 4.897^(1/3)]= 1.65 Setting time of concentration to 5 minutes Rainfall intensity(1)= 7.1 14(In/Hr)fora 100.0 year storm Effective runoff coefficient used for area(Q=KCIA)is C=0.850 Subarea runoff= 0.181(CFS) Total initial stream area= 0.030(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.000 to Point/Station 23.000 **** INITIAL AREA EVALUATION **** User specified'C'value of 0.850 given for subarea Initial subarea flow distance = 28.000(Ft.) Highest elevation= 185.000(Ft.) Lowest elevation= 183 210(Ft.) Elevation difference= 1.790(Ft.) Time of concentration calculated by the urban areas overland flow method(App X-C)= 1.28 min. TC=[1.8*(l.1-C)*distance(Ft.)^.5)/(%slope^(1/3)] TC=[1.8*(1.1-0.8500)*( 28.000^.5)/( 6.393^(1/3)]= 1.28 Setting time of concentration to 5 minutes Rainfall intensity(I)= 7.114(In/Hr)fora 100.0 year storm Effective runoff coefficient used for area(Q=KCIA)is C=0.850 Subarea runoff= 0.060(CFS) Total initial stream area= 0.010(Ac.) End of computations,total study area= 2.325(Ac.) 4. TABLES AND CHARTS h �D O� N 1� O M •-+ O� O� N V'1 V1 t� O O C C O O G O O O C O O O O O 00 0. ,0,.o .. O %0 N h 00 t� O O� 00 OO --+ "T '[f t- C U M M V 't 114: h n Cf• 00 00 00 ' O O C O C O O O O O O G O C O 0. C co c 00 %n v 00 [- c- r- o v v r M 3 (� N M M -*: h V1 h 'O [-� [- 00 00 00 00 C p O O O O O O O O O O O O O O O u U o - C/� .uo d _ ° O �[� � 00 DO N v'f �D �O �O O M M [� H .0 Q N N Ci M V: N V1 "C [� r": 00 00 DO 00 V > C C C C O O O C O C O O C O C "p u 7 93 .o a . o o n o o to o o o " o o kn ar O N N M v v �n �O o0 00 00 °. °. U% w- •-+w } rA ix a F O Ov v O O O O O O O O ° F V y � aaaaaaQaa U 0 e A A A A A A o o V ' o m m 42 cc VO O O� M M O 4 � M 0 Js WWO c 3 a. x x x pG aG x x x x z 0 O t4o, O � C O w C be � . elm Average Values of Rouflaiias Coifficient s RoU4hness 7�i%of waterway z• Coiiiicient (n) I. ' Closed Conduits (1) Steel (not lined) O.OIS Cast Iron MIS Aluminum .021 _. Corrugated Metal (not lined) 0.024 Corrugated Metal (2) (smooth asphalt quarterlining) 0.021 Corrugated Metal (2) (smooth asphalt half lining) 0.018 Corrugated Metal (smooth asphalt full lining) 0.012 • Concrete RCP 0.012 Clay (sewer) 0.013 Asbestos Cement-4 PVe 0.011 - Drain Tile (terra.cotta) 0.015 Cast-in-place Pipe 0.013 Reinforced Concrete Box 0.014 2. Open Channels (1) a. Unlined _ Clay Loam 0.023 0.020 - ..... b.--- Rer•etted Gravel 0.030 Rock 0.040 ' Pipe and Wire - 0.02S Sacked Concrete 0.02S c. Lined , Codcrete (poured) 0.014 Air,Blown mortar (3) 0.016 Asphaltic Concrete or Bituminous Plant Mix 0.018 d. Vegetated (S) Grass lined, maintained .03S ' Grass and Weeds .04S Grass lined.with concrete low flow channel .032 3. Pavement and Gutters (1) Concrete 0.015 Bituminous (plant-mixed) 0.016 _., . ;•'Y....i'! ; .'... ',,;,:� . ;!✓i ,t ,}` .•; ... L = . (:'._ • _ _11pP�10IX XYt; A. l,,.. log - San Diego County Hydrology Manual Section: 3 { Date: June 2003 Page: 12 of 26 _ Note that the Initial Time of Concentration should be reflective of the general land-use at the upstream end of a drainage basin. A single lot with an area of two or less acres does not have a significant effect where the drainage basin area is 20 to 600 acres. Table 3-2 provides limits of the length (Maximum Length (LM)) of sheet flow to be used in hydrology studies. Initial T; values based on average C values for the Land Use Element are also included. These values can be used in planning and design applications as described below. Exceptions may be approved by the "Regulating Agency" when submitted with a detailed study. Table 3-2 MAXIMUM OVERLAND FLOW LENGTH (LM) & INITIAL TIME OF CONCENTRATION (Ti) Element* DU/ .5% 1% 2% 3% 5% 10% Acre LM T; LM T; LM T; LM T; LM Ti LM Ti Natural 50 13.2 70 12.5 85 10.9 100 10.3 100 8.7 100 6.9 LDR 1 50 12.2 70 11.5 85 10.0 100 9.5 100 8.0 100 6.4 LDR 2 50 11.3 70 10.5 85 9.2 100 8.8 100 7.4 100 5.8 LDR 2.9 50 10.7 70 10.0 85 8.8 95 8.1 100 7.0 100 5.6 MDR 4.3 50 10.2 70 9.6 80 8.1 95 7.8 1 100 6.7 1 100 5.3 MDR 7.3 50 9.2 65 8.4 80 7.4 95 7.0 100 6.0 100 4.8 MDR 10.9 50 8.7 65 7.9 80 6.9 90 6.4 100 5.7 100 4.5 MDR 14.5 50 8.2 1 65 7.4 80 6.5 90 6.0 100 5.4 100 4.3 HDR 24 50 6.7 65 6.1 75 5.1 90 4.9 95 , 4.3 100 3.5 HDR 43 50 5.3 65 4.7 75 4.0 85 3.8 95 3.4 100 2.7 N. Com 50 5.3 60 4.5 75 4.0 85 3.8 95 3.4 100 2.7 G. Com 50 1 4.7 1 60 4.1 1 75 3.6 1 85 3.41 90 2.9 1 100 2.4 O.P./Corn 50 4.2 60 3.7 70 3.1 1 80 2.91 90 2.6 100 2.2 Limited I. 50 4.2 60 3.7 70 3.1 80 2.9 90 2.6 100 2.2 General I.' 50 3.7 60 3.2 70 2.7 80 2.6 90 2.3 100 1.9 *See Table 3-1 for more detailed description 3-12 .r • --_� —�—��_� - � —•—rte I!_.I—.�....•.•-rl--------_- .--... .-tt.� �tt.-�t�at��tttl��t►/tt..tt��..t.►.............-�� tt.�.t• .t.tt.�=. AF�t�/t-.=///- r Amp"w�illillip,AS WW An MMM ��////�I�aar�/�aaf, /alas...■\�� SI►S/s.�r/SI�r�S/�I/Illlllll��es�1�� • ��W—MWMN aa!�af1�.��af,/1lalalall\aNSWE■/W� �� ///Y/�///��WA�rJ•�/111 11111 ■■■�>1��0; %%% • MME///////IIMIMM�"WA111I111111■■■■NUMEN mom MMIWAWt///t WAMA IMMt WM1111111111■■■■NMEMM W AM ----- ---- - -- -- --- -- ------ - Y Y tt. .tt-".M OMM 1l,.t/s ��t-Y as.�.l.f•.t�.It..tt.a........-�� cYV/I/t/t►—,... /ga.@W �aaaa.��.Ya�a.a alarmaa a flaaaaa�■11....■■........�a.aal �Y�.W��-r/./.r�r�t•�t��Mg=Y.s Y MU 7. ��.�.��.�as.��as a�.aaaa�.l laa la■■........�� asa./ajF////—aaarMWAW�aal�a�a�a�aaaaiaaa� �allaaaaaalalal\Na1a1l�a■ /IT/////AW/W.N// �W�� mm�� ■It■UNO� �L//V�//S��v�'�%%��f��1111111111■■■■ls��/\■ IIr!'IIW/!!OF"!= AM ��'d MM ��1111111111■■■■U�U/�■ /.I/II'/AW.4 IA=" MBA MM%��1111111111■■■■��//■ - ►/'/%%///W/WAS//fM WAN lIII IN�f�l�f♦f�111f111111��t��fa��>• . /.�I I�//f�I.�f��/��f•�fa•f�fa•f�1111111111�/��fi/fib■ . '/�%�'��%f�`��%%f��f��lilillllll��fifi��■ �i/il/flif/ift/l�il�l�ifa•�%%f•fa•f�f�f♦1111111111��/�fifl�■ iii//�fi/fl�fi�f�f//�_�_f•�1��_�_IIIIIIIIIII��li�fififi■ . NA•W W,��III�f111�111i1111111�linoleum . W S3inNIIN NI 3VRI MOIJ ONtlla3AO V, c°r) N ° o O 0 , to ' d O V Of n O J 0 Z 3 0 °o`` c OR v � 0 V. � C LL t• p� v ea m J I Q� o 000 'r'• E o C l. p^ n L CD "t O cc U Q C j c O CD N 1 a3 �n �C � ID CD 133A NI 30NVISIG 3sunOOH31VM WW F. katbr and Noracs WHIMS Kb g Ale OK W OF 7 t i Table 7-1.1. Values. of h' for Circular Channels in the Formula d«,st.. D - depth of water d a diameter of cbanncl _ L ( 02 .03 .04 .05 .OG .07 I .08 ' 9.0 d .00 .O 1 I _ . .0 .00007•.00031 .00074•.00138•.00222 .00328 .00455 .00604•.0077- .1 .00967 .0118 .0142 .01 G7 .0195 .0225 .0257 .0291 .0327 .0366 ..2 .04%) .0448 .044*2 .0537 .058: .0634 ' .0686 .0738 .0793 .0849 .3 .0907 .0966 .1027 .108(1 .1153 .1218 .128.1 .1352 .1420 .1490 • .4 .1561 .1633 1.1705 .1779 .1854 .1929 .2005 .2082 .2160 .2238 .5 .232 .239 .247 .255 .2G3 .271 .279 .287 .295 .303 .6 .311 .319 .327 .335 .343 .350 .358 AN .373 .380 •7 .865 :395 .402 .4041 .•116 .422 .429 .435 .441 .447 •9 .414 .458 ' .463 .468 .473 .477 .461 .485 .488 .491 .9 •494 .496 .497 .498 .498 .498 .496-•%P. .49'4 .489 .483 1.0 .463 . 5. HYDROLOGY MAP I I � I N N on I y I x � — m I ca I I I I H I x 0 I�I I p - - - - - -coNC - - I F I Ll I H S � e F � I _ o I tiI I N N O IJ/f N � P m 1 JSTING CONDITION _ Q(% ni C • 1 do _ Ap . f �! ur k k S. J� J'V4 w kc.0.93• \ gFAR oescu REp 4 EA;8LOc �r 1 IaZ.ce, g k ti srAlRs x l EX pA O`NC nor o R R£INNIN6 w A4 A 2 k N4S�R u N(,�y�PER O CAtOA./7lgys ri wAQ �09 aEAR m N ARK,Y� ti m WAY O (AryE. C, k�P � � y 07), pia EX ` sr'uby,0 �rAs �� V'wt SIN 1 W ,84. 90. /y_ 20 1 INV �, 1FR*A R W '0 SF D eotD 776 114,1 p APPENDIX D 6, BIO-SWALE NUMERIC SIZING .B R1C,O_S,WALE NUMF SIZING Given: C=0.85 ercentile) 1--0.2 11/hr (85th p area) A-- 1.96 Acres (swale',tributary Q= C N I x A Flow) Q 0.85 x 0.2 % 1.96= 0.33 C.F.S. (,Water Quality == 4,-4" 16" 16" Manning's Channel Calculator Given Input Data, Trapezoidal Shape ........................... Solving for ••••••••••••••••""' ...*................ Depth of Flow 0.3300 cfs Flowrate ........................ 0.0400 ft/ft Slope .............. 0.2500 C C &EAMU"Je) Manning's n ..•••••••••••• 8*.0000 in Height.......................... ..... 52-0000 in Bottom width ..............* Left slope ...................... 0.5000 ft/ft((VV[H)[H) Right slope ..................... 0.5000 ft/ft Computed Results: Depth ........................... 2.2789 in Velocity ........................ 0.3687 fps Full Flowrate ................... 2.8909 cfs Flow area .......... 0.8951 ft2 Flow perimeter .................. 62.1917 in Hydraulic radius ................ 2.0725 in Top width ...............--.. 61.1158 in 7778 ft2 3 Area ...................... 87.7771 in **-- . Perimeter ..............•••'•"" ... Percent full .................... 28.4868 % L ot'>-1 FPS YV-\ > -T C 0 &5 v-A 1 e ' vw :n p .gip► �I� � 11, ► a 1�I .. P-Ira• .III► � �., I 1 O sir w��!�w �w��---�._ _., yQ.r■■�■! .��.�� _-- w all ago- ONA MTV Oil ,� 11►,` �� - ��► ILL._ _;I ._. - . ML aw i, � �....,• _ � � rid �..� y � � sr• .�I�� "ate.,.' -� �� :3 � , I R�;`��.- �►ice • �-- .�,,�>�� I�1 ' II/1�� ►- - �i r _... . ;.. �,..........-. .. '.� ,", � dal,: �'I �-- --�=__--- ;• I}.�► 1 INSIk �■'�� :ice- owning p! SITE ` era �� 041 slim; � �• � �i I; ;N\ i �\ ��•�� ;� C��i i� Fig Al .W1t X11..111,; t� � Ifr` •�` C' I 1�.IIrt1 i' 1 \.�qm1 < ( 1 ` I I i 777, �� ,�aa.-a.ra..:.-.w.'•"v.,�� ISM+ dAt _ •1� A �► ,% • i;il 1 1 •'-•fie°J � � '��--_. ,milli I i � Leighton Consulting, Inc. A LEIGHTON GROUP COMPANY -- January 7, 2005 Project No. 600344-001 To: Grace Partners, LLC 617 Saxony Place, Suite 104 Encinitas, California 92024 Attention: Mr. Allen Jaffe Subject: Geotechnical Response to the City of Encinitas Review of the Project Geotechnical Report, Garden View Office Building, Lots 4 and 5 of Garden View Plaza, Encinitas Tract No. 4255, Encinitas, California Introduction This letter presents our response to the City of Encinitas review comments concerning project geotechnical report for the Garden View Court Office Building (Lots 4 and 5 of Garden View Plaza, Encinitas Tract No. 4255) located in Encinitas, California. As part of our response, we have performed a review of the referenced the project grading plans (K & S Engineering, 2004) and the project geotechnical report (Leighton, 2004) and have performed additional analysis relative to the geotechnical aspects of the project. Based on our review and analysis, our response to the review comments (Geopacifica, 2004) dated December 14, 2004 are provided below: Review Comments ♦ Item No. 1: The project report utilized a tentative map prepared by Burkett and Wong. A review of the proposed grading plan needs to be performed to determine if all of the recommendations oj'the geotechnical report have been addressed. We have performed a geotechnical review of the current grading plans (K& S Engineering, 2004) for the Garden View Court Office Building. Our review was performed to identify potential conflicts with the intent of the referenced project geotechnical report (Leighton, 2004). Based on our review, we are of the opinion that the plans were prepared in general conformance with the geotechnical report. 3934 Murphy Canyon Road,Suite 8205■San Diego, CA 92123-4425 858.292.8030■Fax 858.292.0771 ■www.leightonconsulting.com 600344-001 ♦ Item No. 2: The geotechnical consultant needs to provide a statement that the previously placed fills are acceptable and they accept the previous geotechnical reports and that they are now the geotechnical consultants of record for the site. Based on our review of the as-graded and other geotechnical documents concerning the grading of the site that was performed between 1987 and 1990 and our analysis during our geotechnical investigation, the existing fill soils were compacted to a minimum 90 percent relative compaction and appear to be suitable. However, the upper 1 to 2 feet of the fill appears to be loose and/or disturbed, and potentially compressible and should be removed. We recommend that if the fill soils are not removed by the planned grading, the left-in-place fill soils within the limits of the proposed development be evaluated to determine their suitability. If the fill soils are found not to be suitable for the support of additional fill or improvements, the soil should be removed and replaced with properly placed and compacted fill. Based on results of our letter dated January 6, 2005 (Leighton, 2005c) concerning the findings and conclusions of the previous geotechnical documents prepared by Geotechnical Exploration, Inc. relative to the project, we accept the findings and conclusions of the Geotechnical Exploration, Inc. reports. Our letter dated January 6, 2005 (Leighton, 2005c) also indicates we are now the geotechnical consultant for the project. -- ♦ Item No. 3: Slope stability analysis of both cut and fills slopes on the property need to be performed. - Utilizing the current grading plan prepared by (K & S Engineering, 2004), we prepared three cross-sections through the cut and fill slopes on the south and west sides of the property. The approximate locations of the cross-sections are shown on the attached -- Geotechnical Map (Plate 1) which uses the current grading plan prepared by K & S Engineering. Also shown on Plate 1, are the existing geotechnical conditions and proposed remedial overexcavation limits for the building. Based on the existing as-graded conditions of the slopes around the perimeter of the project and the proposed grading, we performed a slope stability analysis of the slopes. The results of our slope stability analysis is presented as Appendix B. The results of our slope stability analysis indicates that the slopes around the perimeter of the property possess a factor-of- safety of 1.5 or greater. -2- Leighton 600344-001 ♦ Item No. 4: Minimum pavement sections required by the City of Oceanside (sic) is 4 inches AC —• over 6 inches of Class II base. All curb and gutter requires a minimum of 6 inches of Class H base under it. The City of Encinitas minimum thicknesses of asphalt concrete (AC) and Class 2 aggregate base material (AB) mentioned above are noted and will be utilized in the future pavement section recommendation letter for the project. For planning purposes, the pavement section for the project assuming an R-Value of 30 and a Traffic Index of 5 should be 4 inches of AC over 6 inches of AB. The pavement section for the project assuming an R-Value of 30 and a Traffic Index of 6 should be 4 inches of AC over 7 inches of AB. If you have any questions regarding this letter, please contact this office. We appreciate this opportunity to be of service. Respectfully submitted, Q�pT-ESS1pN LEIGHTON CONSULTING, INC. IL p,N1 Q• p < 3 No. 45283 » h a--Z'Je__ E P. j r i�+� William D. Olson, RCE 45283 Senior Project Engineer - £O CALIF ss, L D K. -I L. � Q``o\oP�� ly'9COv,f' Randall K. Wagner,CEG 161 a No. 1612 m Senior Associate * GINEEAIN � ENGINEEpiNG s GEOLOGIST rgr�OF CAI�FOQ, Attachments: Plate 1 -Geotechnical Map -- Appendix A - References �• x•06 Appendix B - Slope Stability Calculations $ Distribution: (4) Addressee (3) K&S Engineering, Attention Mr. Gustavo Miranda (1) Lusardi Construction Company, Attention: Mr. Tim O'Brist -3- Leighton 600344-001 APPENDIX A References Geopacifica, 2004, Review of Geotechnical Reports and Grading Plan, Foundation Plan Review, Lots 4 and 5 of Garden View Plaza, Encinitas Tract 4255, Encinitas, CA, 1 Page, dated December 14, 2004. K & S Engineering, 2004, Grading and Erosion Control Plan For Garden View Office Building, Lots 4 and 5 of Encinitas Tract No. 4255, Drawing No. 9183-GR, 5 Sheets, dated November 10, 2004. Leighton and Consulting, Inc., 2004, Preliminary Geotechnical Investigation, Lots 4 and 5 of Garden View Court, Encinitas Tract No. 4255, Encinitas, California, Project No. 600344- 001, dated April 2, 2004. , 2005a, Geotechnical Response to the City of Encinitas Plan Check Comments Concerning the Garden View Office Building, Lots 4 and 5 of Garden View Plaza, Encinitas Tract No. 4255, Encinitas, California, Project No. 600344-001, dated January 4, 2005. , 2005b, Addendum Geotechnical Recommendations Relative to the Overexcavation of the Proposed Building, Garden View Court Office Building, Lots 4 and 5 of Garden View Plaza, Encinitas Tract No. 4255, Encinitas, California, Project No. 600344-001, dated January 4, 2005. , 2005c,Change of Geotechnical Consultant, Garden View Court Office Building, Lots 4 and 5 of Garden View Plaza, Encinitas Tract No. 4255, Encinitas, California, Project No. 600344-001, dated January 6, 2005. 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A LEIGHTON GROUP COMPANY April 2, 2004 Project No. 600344-001 To: Grace Partners, LLC 617 Saxony Place, Suite 104 Encinitas,California 92024 Attention: Mr. Allen Jaffe Subject: Preliminary Geotechnical Investigation, Lots 4 and 5 of Garden View Plaza, Encinitas Tract No. 4255, Encinitas, California In accordance with your request and authorization, we have performed a preliminary geotechnical investigation for the proposed commercial development of Lots 4 and 5 of Garden View Plaza (Encinitas Tract No. 4255) located in Encinitas, California. Based on the results of our study, it is our professional opinion that the site is suitable for a proposed commercial development and improvements as indicated on the tentative map/grading plan of the project prepared by Burkett& Wong, dated December 12, 2003. _. The accompanying report presents a summary of our investigation and provides preliminary geotechnical conclusions and recommendations relative to the proposed site development. If you have any questions regarding our report, please do not hesitate to contact this office. We appreciate this opportunity to be of service. ,��AEO flE� Respectfully submitted, K. LEIGHTON CONSULTING °"" '° � �No. 16 CERTIFIED ENGINEERING D. ®!<<r� GEOLOGIST 4::1 �rFoF e If & No. 4521 s gyp. 3,z .06 � William D. Olson, RCE, all K. Wagner, G 1612 Senior Project Engineer l C1 for Associate v' Distribution: (4) Addressee (1) KMA Architecture& Engineering Attention Mr. Don Blair (1) Burkett & Wong Attention Mr. Tony Ambrose (1) Lusardi Construction Company Attention: Mr. Tim O'Brist 3934 Murphy Canyon Road,Suite 8205■San Diego,CA 92123-4425 858.292.8030■Fax 858.292.0771 ■www.leightonconsulting.com 600344-001 TABLE OF CONTENTS Section Page 1.0 INTRODUCTION ...........................................................................................................1 1.1 PURPOSE AND SCOPE................................................................................................... 1 1.2 SITE LOCATION AND DESCRIPTION..................................................................................1 1.3 PREVIOUS SITE DEVELOPMENT.......................................................................................3 1.4 PROPOSED DEVELOPMENT.............................................................................................3 2.0 SUMMARY OF GEOTECHNICAL CONDITIONS..................................................................4 �. 2.1 GEOLOGIC SETTING.....................................................................................................4 2.2 SITE-SPECIFIC GEOLOGY ..............................................................................................4 2.2.1 Artificial Fill, Documented (Map Symbol - Afo).....................................................4 2.2.2 Tertiary Torrey Sandstone (Map Symbol —Tt).....................................................5 2.3 GEOLOGIC STRUCTURE.................................................................................................5 2.4 SURFACE AND GROUND WATER ......................................................................................5 2.5 SLOPE STABILITY ........................................................................................................6 3.0 FAULTING AND SEISMICITY..........................................................................................7 3.1 FAULTING .................................................................................................................7 3.2 SEISMICITY...............................................................................................................7 3.2.1 Shallow Ground Rupture ...................................................................................8 -- 3.2.2 Liquefaction .....................................................................................................9 3.2.3 Earthquake-Induced Settlement.........................................................................9 3.2.4 Lateral Spread..................................................................................................9 — 3.2.5 Tsunamis and Seiches..................................................................................... 10 3.2.6 Building Code Seismic Parameters..................................................................... 10 4.0 CONCLUSIONS ........................................................................................................... 11 5.0 RECOMMENDATIONS.................................................................................................. 13 5.1 EARTHWORK............................................................................................................ 13 5.1.1 Site Preparation.............................................................................................. 13 5.1.2 Excavations and Oversize Material ................................................................... 13 5.1.3 Overexcavation of Cut/Fill Transition Condition ................................................. 14 5.1.4 Fill Slope Keys................................................................................................ 14 5.1.5 Remedial Grading and Fill Placement................................................................. 14 5.1.6 Expansive Soils and Selective Grading .............................................................. 15 5.2 TEMPORARY EXCAVATIONS.......................................................................................... 15 5.3 SURFACE DRAINAGE AND EROSION................................................................................ 16 5.4 FOUNDATION AND SLAB CONSIDERATIONS ...................................................................... 16 5.4.1 Preliminary Foundation and Slab Design........................................................... 16 5.4.2 Settlement..................................................................................................... 18 5.4.3 Earth and Hydrostatic Wall Pressures............................................................... 18 -i- Leighton 600344-001 TABLE OF CONTENTS (Continued) Section Paqe 5.5 GEOCHEMICAL CONSIDERATIONS................................................................................. 20 5.6 PRELIMINARY PAVEMENT DESIGN ................................................................................. 20 5.7 SLOPE MAINTENANCE GUIDELINES................................................................................ 21 5.8 CONTROL OF SURFACE WATER AND DRAINAGE................................................................. 22 5.9 LANDSCAPING AND POST-CONSTRUCTION PRACTICES......................................................... 22 5.10 CONSTRUCTION OBSERVATION AND TESTING AND PLAN REVIEW........................................... 23 6.0 LIMITATIONS............................................................................................................. 24 TABLES TABLE 1 - DETERMINISTIC SEISMIC HAZARD ANALYSIS- PAGE 7 TABLE 2 - TEMPORARY EXCAVATION RECOMMENDATIONS- PAGE 14 TABLE 3 - PRESOAKING RECOMMENDATIONS BASED ON FINISH GRADE SOIL EXPANSION POTENTIAL- PAGE 16 TABLE 4 - STATIC EQUIVALENT FLUID WEIGHT(PCF) - PAGE 17 TABLE 5 - MSW WALL SOIL PARAMETERS- PAGE 19 TABLE 6 - PRELIMINARY PAVEMENT SECTION DESIGNS- PAGE- 20 FIGURE FIGURE 1 - SITE LOCATION MAP- PAGE 2 PLATE PLATE 1 - GEOTECHNICAL MAP- IN POCKET APPENDICES APPENDIX A - REFERENCES APPENDIX B - SEISMIC ANALYSIS APPENDIX C - GENERAL EARTHWORK AND GRADING SPECIFICATIONS FOR ROUGH GRADING -ii- Leighton 600344-001 1.0 INTRODUCTION 1.1 Purpose and Scope _ This report presents the results of our preliminary geotechnical investigation for the proposed commercial development of Lots 4 and 5 of Garden View Plaza (Encinitas Tract No. 4255) located in Encinitas, California. Our investigation included a _. geotechnical review of the existing geotechnical reports of the site including the as- graded report (Appendix A) and a site reconnaissance. The purpose of the preliminary geotechnical investigation was to evaluate existing geotechnical conditions present at the site and provide preliminary conclusions and geotechnical recommendations relative to the proposed commercial development of the site. 1.2 Site Location and Description The proposed project is located at the northwest corner of Garden View Road and Garden View Court (and east of El Camino-Real) in the City of Encinitas, California (Figure 1). Lots 4 and 5 of Garden View Plaza (Encinitas Tract No. 4255), which were graded in —' 1989, consist of two relatively level building pads with a slope separating the two buildings pads and perimeter slopes. The building pad of Lot 4 ranges from an approximate elevation of 167 feet mean sea level (msl) at the northwest corner to an approximate elevation of 161 feet msl at the southeast corner. The building pad of Lot 5 ranges from an approximate elevation of 184 feet mean sea level (msl) at the northwest corner to an approximate elevation of 180 feet msl at the southeast corner. The south-facing slope between the building pads ranges _ from 13 to 15 feet in height. The slope on the north side of Lot 5, which is on the order of 7 to 8 feet in height, ascends to the adjacent Lot 6 building pad. The slope on the south side of Lot 4, which is on the order of 2 to 12 feet in height, descends to Garden View Road. Currently, vegetation on the site consists of sparse weeds and small shrubs on the T building pads, groundcover on the slopes on the north and south sides of Lot 5 and landscaping groundcover and small trees on the perimeter slopes on the south and west sides of the site. -1 Leighton L UC � LA AREN4 AV CO q D't B ARBO�FS <� D JACARANDA L VD a 0 2 C t Sn, FpTF� 3 "`'wILLOWHPA '• DR ORCHARD PD Dec m � m c �Y f a •.ME�� _ - CO,?. SCO'\ �ti BFP� • wy qcF PL WANDERING �, RD ��Rl q �1P ro ORANGE FIELDS T � J A10y —I m r R� 1LL0 ��~ m 3 aQ 4 GAR 9`r 4 r-- s z 'FICA AD VAN col G Q PROJECT ✓' NG WY SITE CIR J J LAG A ENI A N TE r— r VALLEDA z � n ro ° m c°* ° ° o GRAN° �- 2 �� z ELOIV m PLO ° °AVENIDA r^ es RD ZENq /Y NORTH BASE MAP: 2003 Digital Edition Thomas Guide, San Diego County NOT TO SCALE Project No. � Lots 4 and 5 of SITE 600344-001 4W Garden View Plaza LOCATION Encinitas, California Date MAP April 2004 Figure No. 1 600344-001 1.3 Previous Site Development The site was graded between June and December 1989 (GEI, 1990a). Prior to the grading activities, Lots 4 and 5 generally consisted of a gentle west to southwest-facing hillside. Pregraded elevations across the two lots ranges from an approximate elevation of 195 feet msl in the northeast corner of Lot 5 to an approximate elevation of 152 feet msl in the southwest corner of Lot 4. -- Grading of the two lots consisted of the excavation of formational material and the placement of minor fills at the southwest corners of both Lots 4 and 5 (as indicated on Plate 1) creating the relatively level building pads and associated slopes. According to the as-graded report (GEI, 1990a), the maximum fill thickness on Lots 4 and 5 are the order of 10 and 12 feet, respectively. In addition, the as-graded report indicated that complete removals of the colluvium and topsoil were performed and that the fill soils were moisture conditioned to a near optimum moisture content and compacted to at least 90 percent relative compaction (based on American Standard of Testing and Materials [ASTM] Test Method D1557). 1.4 Proposed Development Based on a review of the project tentative map/grading plan (Burkett & Wong, 2003), we understand that the two lots will be regraded creating one large pad (i.e. the slope between the lots will be eliminated). That will result in the excavation of material on Lot 5 and the placement of fill on Lot 4. Excavations on the order of 1 to 6 feet and fills on the order of up to 10 feet are proposed. The proposed commercial development of the site will consist of the construction of one building in the middle of the large pad and paved driveways and parking areas ° surrounding the north, west, and south sides of the building. Retaining walls are also proposed along the north, south, and southwest sides of the lot. Associated improvements are also anticipated to include underground utilities, concrete flatwork, landscaping, and bio-swale along the southern perimeter. We also understand that the proposed commercial building will be a one to two-story structure on a concrete slab-on-grade foundation and concrete tilted-up construction. -- -3 Leighton 600344-001 2.0 SUMMARY OF GEOTECHNICAL CONDITIONS 2.1 Geologic Setting The subject site is located in the coastal section of the Peninsular Range Province, a geomorphic province with a long and active geologic history throughout Southern California. Throughout the last 54 million years, the area known as the "San Diego Embayment" has undergone several episodes of marine inundation and subsequent marine regression, resulting in the deposition of a thick sequence of marine and nonmarine sedimentary rocks on the basement rock of the Southern California batholith. Gradual emergence of the region from the sea occurred in Pleistocene time, and numerous wave-cut platforms, most of which were covered by relatively thin marine and nonmarine terrace deposits, formed as the sea receded from the land. Accelerated fluvial erosion during periods of heavy rainfall, coupled with the lowering of the base sea level during Quaternary time, resulted in the rolling hills, mesas, and deeply incised canyons which characterize the landforms we see in the general site area today. —" 2.2 Site-Specific Geology Based on our review of the as-graded geotechnical report and other geotechnical documents relative to the Garden View Plaza project (Appendix A), the site consists of minor fills and the Tertiary-aged Torrey Sandstone. A brief description of the geologic units present on the site is presented below. 2.2.1 Artificial Fill Documented Lap Symbol - Afo) Artificial fill soils placed during the site's rough grading operations are present in the southwestern portions of the building pads of both Lots 4 and 5. Engineering observations and testing of the fill was provided at the time of grading as documented in the as-graded report (GEI, 1990a). As indicated in the as-graded report and observed during our site reconnaissance, the fill soils consist of light brown to brown, slightly moist to moist, medium dense silty fine to medium grained sands. However, the upper I to 2 feet of fill appears to be loose and/or disturbed, and potentially compressible. Laboratory tests performed during the grading operations indicate the soils have a low to very low expansion potential. The approximate limits of the fill soils are presented on the Geotechnical Map (Plate 1). 4C -4- Leighton 600344-001 2.2.2 Tertiary Torrey Sandstone (Map Symbol —Tt) The Tertiary-aged Torrey Sandstone, which is present below the fill soils and at grade on remainder of the site, consists primarily of massively bedded silty sandstones. Based on the as-graded report (GEI, 1990a) and observed during our site reconnaissance, the sandstone generally consists of light brown, damp to moist, dense to very dense, silty fine to medium grained sandstone. The expansion potential of the sandstones is anticipated to be very low to low; however, expansion potential testing of the finish grade soils should be performed to determine the actual expansion potential of the onsite soils. 2.3 Geologic Structure Based on our literature review and professional experience on sites with similar soils, the onsite Torrey Sandstone is generally massive with randomly oriented cross-bedding. Landslides, clay seams and/or clay beds were not encountered during the grading of Lots 4 and 5 (GEI, 1990a). Folding or faulting of the onsite sedimentary units is not known or expected. The significance of regional faults is discussed in the following section on Faulting and Seismicity. Jointing on-site is anticipated to be very variable, but predominantly trends subparallel to the pre-existing hillside. Jointing dips are typically moderately to steeply dipping. Jointing is anticipated to be mainly encountered in the upper portion of the bedrock becoming less pronounced with depth. 2.4 Surface and Ground Water No indicate of surface water or evidence of surface ponding was encountered during our investigation. However, surface water may drain as sheet flow across the site during rainy periods and accumulate in the lower elevations of the building pads. Review of the as- graded geotechnical report indicates that groundwater was not encountered during the grading operations (GEI, 1990a). -5- 4C Leighton 600344-001 2.5 Slope Stability Based on the results of our study and our professional experience with similar soils on nearby sites, it is our opinion that the existing and proposed slopes will be stable from a geotechnical standpoint provided adverse geologic conditions are not present. We recommend that the slopes be geologically mapped during the planned grading operations to verify our assumptions. -6- Leighton 600344-001 3.0 FAULTING AND SEISMICITY 3.1 Faulting Our discussion of faults on the site is prefaced with a discussion of California legislation and state policies concerning the classification and land-use criteria associated with faults. By definition of the California Mining and Geology Board, an active fault is a fault, which has had surface displacement within Holocene time (about the last 11,000 years). The state geologist has defined a potentially active fault as any fault considered to have been active during Quaternary time (last 1,600,000 years). This definition is used in delineating -- Earthquake Fault Zones as mandated by the Alquist-Priolo Earthquake Faulting Zones Act of 1972 and as most recently revised in 1997 (Hart, 1997). The intent of this act is to assure that unwise urban development and certain habitable structures do not occur across the -- traces of active faults. Based on our review, the site is not located within any Earthquake Fault Zone as created by the Alquist-Priolo Act. A review of available geologic literature pertaining to the subject site indicates that there are no known active regional faults that transect the subject site (Appendix A). The nearest known active regional fault is the Rose Canyon Fault Zone located approximately 4.7 miles west of the site (Blake,2000). 3.2 Seismicity The principal seismic considerations for most structures in southern California are surface rupturing of fault traces and damage caused by ground shaking or seismically induced ground settlement. The effects of seismic shaking can be reduced by adhering to the most recent edition of the California Building Code and design parameters of the Structural Engineers Association of California. From a deterministic perspective, Table 1 indicates potential seismic events that could be produced by a maximum moment magnitude earthquake one of the on nearby active regional faults. A maximum moment magnitude earthquake is the maximum expectable earthquake given the known tectonic framework. Site-specific seismic parameters for the site included in Table 1 are the distances to the causative faults, earthquake magnitudes, and expected ground accelerations as generated by the deterministic fault modeling software EQFAULT (Blake, 2000). The ground acceleration was modeled using the attenuation equation of Abrahamson and Silva(1997). -- The distances and maximum magnitude events in Table 1 were determined using the digitized fault coordinates and summarized magnitudes used by State of California (CDMG, 1996). -7- Leighton 600344-001 Table 1 Deterministic Seismic Hazard Analysis Potential Distance Maximum Horizontal Ground Causative from Fault Slip Rate(2) Moment Acceleration at Fault/Fault to Site(l) (mm/yr) Magnitude<<� Mean Confidence(2) Zone (miles/km) (MW) (g) Rose Canyon 4.7/7.6 1.5 7.2 0.37 -- Newport- 11.9/19.1 1.5 7.1 0.20 Inglewood Coronado Bank 19.6/31.5 3.0 7.6 0.16 (')CDMG, 1996 (2)Blake, 2000 As indicated in Table 1, the Rose Canyon Fault Zone is considered to have the most significant affect at the site from a design standpoint. The maximum moment magnitude earthquake event could produce a peak horizontal ground surface acceleration at the site of 0.36g with a standard deviation of approximately 0.20g. The Rose Canyon Fault Zone is considered a Type B seismic source according to Table 16A-U of the 2001 California Building Code (CBCS, 2001). Summary printouts of the deterministic analyses are provided in Appendix B of this report. Secondary effects associated with severe ground shaking following a relatively large earthquake can include shallow ground rupture, soil liquefaction, lateral spreading, earthquake-induced settlement, and tsunamis/seiches. These secondary effects of seismic shaking are discussed in the following sections. 3.2.1 Shallow Ground Rupture No active or potentially faults are mapped crossing the site and the site is not located within a mapped Alquist-Priolo Earthquake Fault Zone (Hart, 1997). The nearest mapped segment of the Rose Canyon Fault Zone extends to within approximately 4.7 miles west of the site. Cracking due to shaking from distant seismic events is not considered a significant hazard, although it is possible at any site. -8- Leighton 600344-001 3.2.2 Liquefaction Liquefaction of soils can be caused by strong vibratory motion due to earthquakes. Both research and historical data indicate that loose, saturated, granular soils are susceptible to liquefaction and dynamic settlement. Liquefaction is typified by a - reduction in of shear strength in the affected soil layer. Liquefaction may be manifested by excessive settlement, sand boils, and bearing failure. The dense sandy fill and bedrock materials at the site are not considered liquefiable due to their high density, fine-grained nature, and generally unsaturated conditions. 3.2.3 Earthquake-Induced Settlement Granular soils tend to densify when subjected to shear strains induced by ground shaking during earthquakes. Simplified methods were proposed by Tokimatsu and Seed (1987) and Ishihara and Yoshimine (1992) involving SPT N-values used to estimate earthquake-induced soil settlement. Due to low susceptibility of the site to liquefaction, the potential for earthquake- induced settlements is considered to be low during strong ground shaking. Earthquake-induced settlements tend to be most damaging when differential N settlements result. Earthquake-induced total and differential settlement are expected to be negligible. 3.2.4 Lateral Spread Empirical relationships have been derived by Youd and others (Youd, 1993; Bartlett and Youd, 1995; and Youd et al., 1999) to estimate the magnitude of _ lateral spread due to liquefaction. These relationships include parameters such as earthquake magnitude, distance of the earthquake from the site, slope height and angle, the thickness of liquefiable soil, and gradation characteristics of the soil. The susceptibility to earthquake-induced lateral spread is considered to be low for the site because of the low susceptibility to liquefaction and general absence of ground water in the site vicinity. -9- -- Leighton 600344-001 3.2.5 Tsunamis and Seiches Based on the distance between the site and large, open bodies of water, and the elevation of the site with respect to sea level, the possibility of seiches and/or tsunamis is considered to be very low. 3.2.6 Building Code Seismic Parameters The effect of seismic shaking may be mitigated by adhering to the California Building Code (CBC) or state-of-the-art seismic design parameters of the Structural Engineers Association of California. The seismic parameter settings for the site, per the 2001 CBC, are as follows: Soil Profile Type (Table 16A-J) = SD Seismic Zone 4 (Figure 16A-2)Z = 0.4 Slip Rate, SR, (Table 16A-U) = 1.5mm per year (CDMG, 1996), based on the Rose Canyon Fault Zone Seismic Source Type (Table 16A-U) = B Na= 1.0 (Table 16A-S) N,= 1.0 (Table 16A-T) -10- 4C Leighton 600344-001 4.0 CONCLUSIONS Based on the results of our preliminary geotechnical investigation of the site, it is our opinion that the proposed development is feasible from a geotechnical standpoint, provided the following -- conclusions and recommendations are incorporated into the project plans and specifications. The following is a summary of the geotechnical factors that may affect development of the site. • The site is underlain by older documented fill soils and the Torrey Sandstone. Due to the length of time since the completion of the grading operations, the near-surface soils (i.e., the upper 1 to 2 feet) are locally disturbed and potentially compressible. As a result, these soils - are not considered suitable for support of additional fill soils, structural loads or surface improvements in their present condition. Remedial grading measures such as scarification and/or removal and recompaction will be necessary to mitigate this condition if the disturbed soils are not removed by the proposed grading. Deeper removals may be required if geotechnical observation during the proposed grading operations indicate the deeper fills are not suitable. • Although building plans have not been finalized nor building loads developed, we anticipate _ that a conventional foundation system, consisting of continuous and spread footings with a slab-on-grade foundation and concrete tilt-up walls will be used. • The proposed regrading of the site (creating one large relatively level building pad) will result in a cut/fill transition condition beneath the proposed building. This cut/fill transition condition will need to be mitigated in order to minimize potential differential settlement across the building. • Artificial fill soils placed during the site's rough grading operations are present in the °- southwestern portions of the building pads of both Lots 4 and 5. Engineering observations and testing of the fill was provided at the time of grading as documented in the as-graded report (GEI, 1990a). • Based on our review of the as-graded report and professional experience, the onsite soils generally possess a very low to low expansion potential. Expansive soils, if encountered, should not be placed within the limits of the proposed building location. (unless additional foundation design considerations are taken into account). • We anticipate that the onsite soils have a negligible potential for sulfate attack on normal concrete and are moderately corrosive on buried metal pipes and conduits. This should be confirmed by laboratory testing after the completion of the additional grading operations. -11- -- Leighton 600344-001 • The existing onsite soils appear to be suitable material for fill construction provided they are relatively free of organic material, debris, and rock fragments larger than 8 inches in maximum dimension. • Surface water or groundwater seepage was not noted nor anticipated during our study; however, perched ground water and seepage may develop during periods of precipitation. • Based on the results of our study and our professional experience with similar soils on nearby ® sites, it is our opinion that the existing and proposed slopes will be stable from a geotechnical standpoint provided adverse geologic conditions are not present. We recommend that the slopes be geologically mapped during the planned grading operations to verify our assumptions. • No active or potentially active faults are mapped crossing the site and the site is not located within a mapped Alquist-Priolo Earthquake Fault Zone. _ • The nearest known active regional fault is the Rose Canyon Fault Zone located approximately 4.7 miles west of the site and is considered to have the most significant affect at the site from a design standpoint. The maximum moment magnitude earthquake event could produce a peak horizontal ground surface acceleration at the site of 0.36g with a standard deviation of approximately 0.20g. -- • The dense sandy fill and bedrock materials at the site are not considered liquefiable due to their high density, fine-grained nature, and generally unsaturated conditions. -' • Due to low susceptibility of the site to liquefaction, the potential for earthquake-induced settlements and earthquake-induced lateral spread are considered to be low during strong ground shaking. • The proposed bio-swale along the southern perimeter should be underlined with a subsurface geomembrane and designed to minimize infiltration of water into the wall backfill zone. -12- 4C Leighton W 600344-001 5.0 RECOMMENDATIONS 5.1 Earthwork We anticipate that earthwork at the site will consist of site preparation, excavation, remedial grading and trench backfill. We recommend that earthwork on the site be performed in accordance with the following recommendations and the General Earthwork and Grading Specifications for Rough Grading included in Appendix C. In case of conflict, the following recommendations shall supersede those in Appendix C. 5.1.1 Site Preparation Prior to remedial grading, the site should be cleared of surface and subsurface obstructions, including any existing debris and undocumented or loose fill soils, and stripped of vegetation. Removed vegetation and debris should be properly disposed off-site. Our study indicates that the near-surface soils (i.e., the upper 1 to 2 feet) are - locally disturbed and potentially compressible. We recommend that the upper 12 to 24 inches of the existing ground surface be scarified and/or removed and recompacted. In addition, we recommend that pot-holing of the fill soils that are not removed by the planned grading should be performed during the grading operations to determine the actual removal depths. All areas to receive fill and/or other surface improvements should be scarified to a minimum depth of 12 inches, brought to above-optimum moisture conditions, and recompacted to at least 90 percent relative compaction (based on American Standard of Testing and Materials [ASTM] Test Method D1557). 5.1.2 Excavations and Oversize Material Excavations of the on-site fill and sedimentary materials may generally be accomplished with conventional heavy-duty earthwork equipment. Localized cemented zones in the formational unit may be encountered that may require heavy ripping. All oversized rock that is encountered should be placed as fill in accordance with the recommendations presented Appendix C. -13- -� Leighton 600344-001 5.1.3 Overexcavation of Cut/Fill Transition Condition For building and settlement sensitive structures or improvements having a cut/fill transition condition, remedial grading is recommended to reduce the potential for differential settlement due to differential fill thicknesses. Since the additional grading will result in a cut/fill transition condition across the planned building, we recommend that the cut portion of the building pad be overexcavated to a depth of at least 3 feet below the lowest proposed footing. The lateral extent of the overexcavation should be a minimum of 10 feet beyond the building perimeter. As an alternative, the use of a deepened footing to formational material may be considered. 5.1.4 Fill Slope Keys We recommend that any new fill slope be constructed with a fill slope key placed into competent material. The fill slope key should have a minimum width of 15 feet with the key bottom angled a minimum of 2-percent into the slope. — 5.1.5 Fill Placement The onsite soils are generally suitable for reuse as compacted fill, provided they are free of organic materials and debris. Areas to receive structural fill and/or other surface improvements should be scarified to a minimum depth of 12 inches; brought to an above optimum moisture content; and recompacted to at least 90 percent relative compaction (based on ASTM Test Method D1557). The optimum lift thickness to produce a uniformly compacted fill will depend on the type and size of compaction equipment used. In general, fill should be placed in uniform lifts not exceeding 8 inches in thickness. Placement and compaction of fill should be performed in general accordance with the current City of Encinitas grading ordinances under the observation and testing of the geotechnical consultant, sound construction practices, and the General Earthwork and Grading Specifications for Rough Grading presented in Appendix C. Fills placed on slopes steeper than 5 to 1 (horizontal to vertical) should be keyed and benched into dense formational soils (see Appendix C for benching details). Fills placed within 5 feet of finish pad grades should consist of granular soils of very low to low expansion potential and contain no materials over 8 inches in maximum dimension. Oversize material may be incorporated into structural fills if placed in -- accordance with the recommendations of Appendix C. -14- Leighton 600344-001 Import soils, if necessary, should consist of granular soils of very low to low expansion potential (expansion index 50 or less based on UBC 18-2) and contain no - materials over 8 inches in maximum dimension. 5.1.6 Expansive Soils and Selective Grading It is not anticipated that medium or highly expansive soils will be encountered -- during site grading; however, these soils may be present as thin beds within the formational sandstone. Expansion potential testing should be performed on the finish grade soils to verify the actual expansion potential. If medium or highly expansive soils are present within 5 feet of finish grade, special foundation and slab considerations will be required. 5.2 Temporary Excavations Sloped excavations may be utilized when adequate space allows. Based on our findings, we provide the following recommendations for sloped excavations in fill soils or competent formational materials without seepage conditions. Table 2 Temporary Excavation Recommendations Excavation Depth Maximum Slope Ratio in Fill Maximum Slope Ratio in Below Adjacent Soils Competent Formation Surface (in feet) 0 - 5 '/4:1 (H : V) Vertical 5 - 20 1:1 1:1 -- Excavations greater than 20 feet in height will require an alternative sloping plan or shoring plan prepared by a California registered civil engineer. The above values are based on the assumption that no surcharge loading or equipment will be placed within 10 feet of the top of slope. All excavations should comply with OSHA requirements. Care should be taken during excavation adjacent to the existing structures so that undermining does not occur. The contractor's "competent person" should review all excavations on a daily basis for signs of instability. -15- -� Leighton 600344-001 5.3 Surface Drainage and Erosion Surface drainage should be controlled at all times. The proposed structure should have appropriate drainage systems to collect roof runoff. Positive surface drainage should be provided to direct surface water away from any structure toward the street or suitable -- drainage facilities. Planters should be designed with provisions for drainage to the area drains/storm drain. Ponding of water should be avoided adjacent to the structure. 5.4 Foundation and Slab Considerations Foundations and slabs should be designed in accordance with structural considerations and the following recommendations. These recommendations assume that the soils encountered within 5 feet of pad grade have a very low to low potential for expansion. Additional expansion testing should be performed as part of the fine grading operations. If medium or highly expansive soils are encountered and selective grading cannot be accomplished, additional foundation design will be necessary. 5.4.1 Preliminary Foundation and Slab Design The proposed building may be supported by conventional, continuous or isolated spread footings. Footings should extend a minimum of 24 inches beneath the lowest adjacent soil grade. At these depths, footings may be designed for a maximum allowable bearing pressure of 2,500 pounds per square foot (psf) if founded in properly compacted fill soils. For footings founded in competent formational soils, an allowable bearing pressure of 3,500 psf may be used. The bearing pressure for miscellaneous site retaining walls and other at-grade improvements should be limited to 2,000 psf. The allowable pressures may be increased by one-third when considering loads of short duration such as wind or seismic forces. The minimum recommended width of footings is 18 inches for continuous footings and 24 inches for square or round footings. Footings should be designed in accordance with the structural engineer's requirements and have a minimum reinforcement of four No. 5 reinforcing bars (two top and two bottom). We also recommend a minimum horizontal setback distance from the face of slopes for all structural footings and settlement-sensitive structures. This distance -- is measured from the outside edge of the footing, horizontally to the slope face (or to the face of a retaining wall) and should be a minimum of H/2, where H is the slope height (in feet). The setback should not be less than 10 feet and need not be greater than 20 feet. Please note that the soils within the structural setback area, other than those addressed within this report, possess poor lateral stability, and improvements (such as retaining walls, sidewalks, fences, pavements, etc.) -16- -' Leighton 600344-001 constructed within this setback area may be subject to lateral movement and/or differential settlement. Slabs on grade should be reinforced with reinforcing bars placed at slab mid- height. Slabs should have crack joints at spacings designed by the structural engineer. Columns should be structurally isolated from slabs. Slabs should be a minimum of 5 inches thick and reinforced with No. 4 rebars at 18 inches on center (each way). The slab should be underlain by a 2-inch layer of clean sand (Sand Equivalent [SE] greater than 30). A moisture barrier (10 mil) should be placed below the sand layer if reduction of moisture vapor up through the concrete slab is desired, which is in turn underlain by an additional 2-inches of clean sand. If applicable, slabs should also be designed for the anticipated traffic loading using a modulus of subgrade reaction of 100 pounds per cubic inch. All waterproofing measures should be designed by the project architect. The slab subgrade soils underlying the foundation systems should be presoaked in accordance with the recommendations presented in Table 3 prior to placement of the moisture barrier and slab concrete. The subgrade soil moisture content should be checked by a representative of Leighton Consulting prior to slab construction. Table 3 Presoaking Recommendations Based on Finish Grade Soil Expansion Potential Expansion Potential Presoaking Recommendations (UBC 18-I-B) Very Low Near-optimum moisture content to a minimum depth of 6 inches Low 120 percent of the optimum moisture content to a minimum depth of 12 inches below slab subgrade Medium 130 percent of the optimum moisture content to a minimum depth of 18 inches below slab subgrade Presoaking or moisture conditioning may be achieved in a number of ways. But based on our professional experience, we have found that minimizing the moisture loss on pads that has been completed (by periodic wetting to keep the upper portion of the pad from drying out) and/or berming the lot and flooding for a short period of time (days to a few weeks) are some of the more efficient ways to meet the presoaking recommendations. If flooding is performed, a couple of days to let the -17- 44 Leighton 600344-001 upper portion of the pad dry out and form a crust so equipment can be utilized should be anticipated. 5.4.2 Settlement Differential fill depths of less than 6 to 7 feet are anticipated within the footprint of the proposed building following remedial grading. Based on this configuration, the maximum total and differential settlement is estimated to be 3/4 inch and 1/2 inch or less, respectively. 5.4.3 Lateral Earth and Hydrostatic Wall Pressures For design purposes, the following lateral earth pressure values on Table 4 for level or sloping backfill are recommended for walls backfilled with onsite soils of very low to low expansion potential (expansion potential less than 50 per ASTM Test Method D4829). Table 4 Static Equivalent Fluid Weight (pcf) Conditions Level 2:1 Slope Active 55 75 At-Rest 70 85 150 Passive (Maximum of 3 ksf) (Sloping Down) Unrestrained (yielding) cantilever walls up to 15 feet in height should be designed for an active equivalent pressure value provided in Table 4 above. For the design of walls restrained from movement at the top (nonyielding) such as basement walls, the at-rest pressures should be used. If conditions other than those covered herein are anticipated, the equivalent fluid pressure values should be provided on an individual case basis by the geotechnical engineer. A surcharge load for a _ restrained or unrestrained wall resulting from automobile traffic may be assumed to be equivalent to a uniform horizontal pressure of 75 psf, which is in addition to the equivalent fluid pressure given above. For other uniform surcharge loads, a uniform horizontal pressure equal to 0.35q should be applied to the wall (where q is the surcharge pressure in psf). The wall pressures assume walls are backfilled with free draining materials and water is not allowed to accumulate behind walls. -- A typical wall drainage design is provided in Appendix C. Wall backfill should be -18- Leighton 600344-001 brought to at least 2 percent above the optimum moisture content and compacted by mechanical methods to at least 90 percent relative compaction (based on ASTM Test Method D1557). Wall footings should be embedded at least 18 inches below lowest adjacent grade or deeper, as needed, to attain the recommended slope setback of a minimum horizontal distance from the outside base of the footing to daylight of 10 feet. The wall footings should also be designed in accordance with the foundation design recommendations and reinforced in accordance with structural considerations. Lateral soil resistance developed against lateral structural movement can be obtained from the passive pressure value provided above. Further, for sliding resistance, the friction coefficient of 0.33 may be used at the concrete and soil interface. These values may be increased by one-third when considering loads of short duration including wind or seismic loads. The total resistance may be taken as the sum of the frictional and passive resistance provided that the passive portion does not exceed two-thirds of the total resistance. Design of a proposed Mechanically Stabilized Wall (MSW)retaining wall at the site should be utilized recommended soil parameters presented in Table 5. Temporary sloping should be performed in accordance with current OSHA requirements. Table 5 MSW Wall Soil Parameters Soil Property Reinforced Zone Retained Zone Foundation Zone Internal Friction 30 30 30 Angle, F (degrees) Cohesion, c (psf) 0 0 100 Total Unit Weight 125 125 125 (pcf) Noted that in general, surface water should be prevented from infiltrating into the reinforced soil zone. Specifically, the surface water from the "Bio-swale" located above the MSE wall needs to be designed with a subsurface geomembrane control and prevent water infiltration. The MSW retaining wall should also be designed with a 4-inch diameter, SDR 35 perforated drainage pipe surrounded by 1.5 cubic foot (per lineal foot) of 3/4-inch crushed rock wrapped in filter fabric (Mirafi 140N or equivalent). Additional backdrains may be necessary as determined by field -19- -- Leighton 600344-001 observations at the time of construction. All drains and swales should outlet to suitable locations as determined by the project civil engineer. In addition, the project civil engineer should verify that the subdrain is connected to the proper drainage facility. 5.5 Geochemical Considerations Geochemical screening of the onsite soils was not performed as part of our study. However our review of the as-graded report and other geotechnical documents related to the Garden View Plaza project (Appendix A) indicates that the concrete should be minimally designed in accordance with "negligible" category of Table 19A-A-4 of the 2001 CBC. In addition, the onsite soils are anticipated to have a corrosive environment for buried metal pipes or uncoated metal conduits. Laboratory testing should be performed on the soils placed at or near finish grade after completion of site grading to ascertain the actual corrosivity characteristics. 5.6 Preliminaryy Pavement Design The appropriate pavement section will depend on the type of subgrade soil, shear strength, traffic load, and planned pavement life. Since an evaluation of the actual subgrade soils cannot be made at this time,we have assumed an R-value of 30 and Traffic Indices (TI)of 5 and 6. The range of pavement sections presented on Table 6 is to be used for preliminary planning purposes only. Final pavement designs should be completed in accordance with the City of Encinitas design criteria after R-value tests have been performed on actual subgrade materials. Table 6 Preliminary Pavement Section Designs Traffic Index Preliminary Pavement Section 5 3 inches AC over 8 inches Class 2 Aggregate Base 6 4 inches AC over 10 inches Class 2 Aggregate Base Asphalt Concrete (AC) and Class 2 aggregate base should conform to and be placed in accordance with the latest revision of California Department of Transportation Standard Specifications. Prior to placing the pavement section, the subgrade soils should have a relative compaction of at least 95 percent to a minimum depth of 12 inches (based on -20- -� Leighton 600344-001 ASTM Test Method D1557). Aggregate Base should be compacted to a minimum of 95 percent relative compaction (based on ASTM Test Method D1557) prior to placement of the AC. If pavement areas are adjacent to heavily watered landscaping areas, we recommend some measures of moisture control be taken to prevent the subgrade soils from becoming saturated. It is recommended that the concrete curbing, separating the landscaping area from the pavement, extend below the aggregate base to help seal the ends of the sections where heavy landscape watering may have access to the aggregate base. Concrete swales should be designed if asphalt pavement is used for drainage of surface waters. 5.7 Slope Maintenance Guidelines It is the responsibility of the owner to maintain the slopes, including adequate planting, proper irrigation and maintenance, and repair of faulty irrigation systems. To reduce the potential for erosion and slumping of graded slopes, all slopes should be planted with ground cover, shrubs, and plants that develop dense, deep root structures and require minimal irrigation. Slope planting should be carried out as soon as practical upon completion of grading. Surface-water runoff and standing water at the top-of-slopes should be avoided. Oversteepening of slopes should also be avoided during construction activities and landscaping. Maintenance of proper drainage, undertaking of improvements in accordance with sound engineering practices, and proper maintenance of vegetation, including regular slope irrigation, should be performed. Slope irrigation sprinklers should be adjusted to provide maximum uniform coverage with minimal of water usage and _ overlap. Overwatering and consequent runoff and ground saturation should be avoided. If automatic sprinklers systems are installed, their use must be adjusted to account for rainfall conditions. Trenches excavated on a slope face for any purpose should be properly backfilled and compacted in order to obtain a minimum of 90 percent relative compaction, in accordance with ASTM Test Method D1557. Observation/testing by the geotechnical consultant during trench backfill is recommended. A rodent-control program should be established and maintained. Prior to planting, recently graded slopes should be temporarily protected against erosion resulting from rainfall, by the implementing slope protection measures such as polymer covering,jute mesh, etc. -21- -- Leighton 600344-001 5.8 Control of Surface Water and Drainage _ Surface drainage should be carefully taken into consideration during precise grading, landscaping, and construction of site improvements. Positive drainage (e.g., roof gutters, downspouts, area drains, etc.) should be provided to direct surface water away from the structure and improvements and towards the street or suitable drainage devices. Ponding of water adjacent to the structure should be avoided. Roof gutters, downspouts, and area drains should be aligned so as to transport surface water to a minimum distance of 5 feet away °- from any structure. The performance of structural foundations is dependent upon maintaining adequate surface drainage away from structures. Water should be transported off the site in approved drainage devices or unobstructed swales. We recommend that the minimum flow gradient for the drainage be 2 percent for area drains and paved drainage swales. We recommend that the minimum flow gradient for unpaved drainage swales and paved drainage swales within 5 feet of structures (sloping away) also be 2 percent. In places where the prospect of maintaining the minimum recommended gradient for the drainage swales and the construction of additional area drains is not feasible, provisions for specific recommendations to the owners may be necessary, outlining the importance of maintaining positive drainage. The impact of heavy irrigation or inadequate runoff gradient can create perched water conditions, resulting in seepage or shallow groundwater conditions where previously none _ existed. Maintaining adequate surface drainage and controlled irrigation will significantly reduce the potential for nuisance-type moisture problems. To reduce differential earth movements such as heaving and shrinkage due to the change in moisture content of _ foundation soils, which may cause distress to a structure and improvements, the moisture content of the soils surrounding the structure should be kept as relatively constant as possible. All area drain inlets should be maintained and kept clear of debris in order to function properly. In addition, landscaping should not cause any obstruction to site drainage. Rerouting of drainage patterns and/or installation of area drains should be performed, if necessary,by a qualified civil engineer or a landscape architect. 5.9 Landscal2ing and Post-Construction Practices Landscaping and post-construction practices carried out by the owner and their representatives exert significant influences on the integrity of structures founded on expansive soils. Improper landscaping and post-construction practices, which are beyond _ the control of the geotechnical engineer, are frequently the primary cause of distress to these structures. Recommendations for proper landscaping and post-construction practices are provided in the following paragraphs within this section. Adhering to these -22- Leighton 600344-001 recommendations will help in minimizing distress due to expansive soils, and in ensuring that such effects are limited to cosmetic damages, without compromising the overall integrity of structures. Initial landscaping should be done on all sides adjacent to the foundation of a structure or associated improvements, and adequate measures should be taken to ensure drainage of water away from the foundation or improvement. If larger, shade providing trees are desired, such trees should be planted away from structures or improvements (at a minimum distance equal to half the mature height of the tree) in order to prevent penetration of the tree roots beneath the foundation of the structure or improvement. Locating planters adjacent to buildings or structures should be avoided as much as possible. If planters are utilized in these locations, they should be properly designed so as to prevent fluctuations in the moisture content of the subgrade soils. Planting areas at grade should be provided with appropriate positive drainage. Wherever possible, exposed soil areas should be above paved grades. Planters should not be depressed below adjacent paved grades unless provisions for drainage, such as catch basins and drains, are made. Adequate drainage gradients, devices, and curbing should be provided to prevent runoff from adjacent pavement or walks into planting areas. Watering should be done in a uniform, systematic manner as equally as possible on all sides of the foundation, to keep the soil moist. Irrigation methods should promote uniformity of moisture in planters and beneath adjacent concrete flatwork. Overwatering and underwatering of landscape areas must be avoided. Areas of soil that do no have ground cover may require more moisture, as they are more susceptible to evaporation. Ponding or trapping of water in localized areas adjacent to the foundations can cause differential moisture levels in subsurface soils and, therefore, should not be allowed. Trees located within a distance of 20 feet of foundations would require more water in periods of extreme drought, and in some cases, a root injection system may be required to maintain moisture equilibrium. During extreme hot and dry periods, close observations should be carried out around foundations to ensure that adequate watering is being undertaken to prevent soil from separating or pulling back from the foundation. 5.10 Construction Observation and Testing and Plan Review The geotechnical consultant should perform construction observation and testing during the rough, fine, and post grading operations, future excavations and foundation or retaining wall construction at the site. Additionally, footing excavations should be observed and moisture determination tests of the slab subgrade soils should be performed by the geotechnical consultant prior to the pouring of concrete. Foundation design plans should also be reviewed by the geotechnical consultant prior to excavations. -23- -- Leighton 600344-001 6.0 LIMITATIONS The conclusions and recommendations presented in this report are based in part upon data that were obtained from a limited number of observations, site visits, excavations, samples, and tests. — Such information is by necessity incomplete. The nature of many sites is such that differing geotechnical or geological conditions can occur within small distances and under varying climatic conditions. Changes in subsurface conditions can and do occur over time. Therefore, the findings, conclusions, and recommendations presented in this report can be relied upon only if Leighton has the opportunity to observe the subsurface conditions during grading and construction of the project, in order to confirm that our preliminary findings are representative for the site. f -24- Leighton 600344-001 APPENDIX A References Abrahamson, N.A., and Silva, W.J., 1997, Empirical Response Spectral Attenuation Relationships for Shallow Crustal Earthquakes, Seismological Research Letters, 1997, Volume 68,Number 1, Seismological Society of America, Pub, pp. 94-127. Bartlett, S.F. and Youd, T.L., 1995, Empirical Prediction of Liquefaction-Induced Lateral Spread, Journal of Geotechnical Engineering, Vol. 121,No.4, April 1995. Blake,2000, EQFAULT,Version 3.0. Burkett & Wong, 2003, Tentative Map/Grading plan, Lots 4 and 5 of Encinitas No. 4255, Encinitas, California, 2 Sheets, dated December 22, 2003 CDMG, 1996, Probabilistic Seismic Hazard Assessment for the State of California, Open-File Report, 96-08. California Building Standards Commission (CBSC), 2001, California Building Code, Volume I — Administrative, Fire- and Life-Safety, and Field Inspection Provision, Volume 1I — Structural Engineering Design Provision, and Volume III — Material, Testing and Installation Provision,ICBO. California Division of Mines and Geology, 1983, Guidelines for Evaluating the Hazard of Surface Faulting Rupture: California Division of Mines and Geology,Note 49, 2p. 1996, Probabilistic Seismic Hazard Assessment for the State of California, Open File Report 96-706. Geotechnical Exploration, Inc. (GEI), 1987, Report of Geotechnical Investigation, Garden View Plaza-Unit No. 1 and No. 2, County of San Diego (Tentative Map) Tract 4255, Lot 1-7, El Camino Real and Garden View Road, Encinitas, California, Job No. 86-4824, dated February 13, 1987. , 1989a, R-value Test Results and Preliminary Pavement Cross Section Recommendations, El Camino Real and Garden View Court, Garden View Plaza, County of San Diego Tract No. 4255, El Camino Real and Garden View Road, Encinitas, California, Job No. 86-4824, dated September 19, 1989. 1989b, Soil Corrosivity Test Results, Proposed Corrugated Metal Pipe, Garden View Plaza, Garden View Drive and El Camino Real, Encinitas, California, Job No. 87-4824, dated October 19, 1989. A-1 600344-001 APPENDIX A (Continued) 1990a, Final Report of Rough Grading Observation and Field Density Testing, Utility Trench Testing, and Street Improvement Testing, Garden View Plaza, County Tract No. 4255, Northeast and Southeast of the Intersection between El Camino Real and Garden View Court, Encinitas, California, Project No. 86-4824, dated January 18, 1990. -- , 1990b, Report of Limited Geotechnical Investigation for Proposed Cribwalls, Lots 1, 2, 3, Proposed Garden View Plaza, Northeast Quadrant of El Camino Real and Garden View Road, Encinitas, California, Job No. 90-5828, dated August 21, 1990. Hart, 1997, Fault Rupture Hazard Zones in California, Alquist-Priolo Special Studies Zones Act of 1972 with Index to Special Study Zone Maps, Department of Conservation, Division of Mines and Geology, Special Publication 42, revised 1997. International Conference of Building Officials, 1997, Uniform Building Code. Ishihara, K., and Yoshimine, M., 1992, Evaluation of Settlements in Sand Deposits Following Liquefaction during Earthquakes, Soils and Foundations, Vol. 32,No. 1, pp: 173-188. Jennings, C.W., 1994, Fault Activity Map of California and Adjacent Areas; California Division of Mines and Geology, Geologic Data Map 6, Scale 1:750,000. Kennedy, M.P. and Welday, E.E., 1980, Character and Recency of Faulting Offshore Metropolitan San Diego, California: California Division of Mines and Geology Map Sheet 40. Rick Engineering, 1990, As-Built Grading Plans for Garden View Plaza, Encinitas, California, Grading Permit No. L-1174, Sheet 3 of 12, dated June 20, 1990. Tokimatsu, K. and Seed, H.B., 1987, Evaluation of Settlements in Sands Due to Earthquake Shaking,Journal of Geotechnical Engineering,ASCE,Vol. 113,No. 8,pgs. 861-878. Treiman, J.A., 1993, The Rose Canyon Fault Zone, Southern California: California Division of Mines and Geology, Open-File Report 93-02,45 p. Youd, T.L., 1993, Liquefaction-Induced Lateral Spread Displacement, NCEL Tech. Note 1862, Naval Civil Engineering Laboratory, Port Hueneme, California. Youd, T.L., Hanson C.M., and Bartlett, S.F., 1999, Revised MLR Equations for Predicting Lateral Spread Displacement, Proceedings of the 7 1 U.S.-Japan Workshop on Earthquake Resistant Design of Lifeline Facilities and Countermeasures Against Soil Liquefaction, November 19, 1999, pp. 99-114. A-2 600344-001 APPENDIX A (Continued) Ziony, J.I., and Yerkes, R.F., 1985, Evaluating Earthquake and Surface-Faulting Potential in Ziony, ed., 1985, Evaluating Earthquake Hazards in the Los Angeles Region-An Earth- Science Perspective: U.S. Geological Survey, Professional Paper 1360,pp. 43-91. A-3 *********************** * * * E Q F A U L T * * * Version 3 .00 * * *********************** DETERMINISTIC ESTIMATION OF PEAK ACCELERATION FROM DIGITIZED FAULTS JOB NUMBER: 600344-001 DATE: 03-29-2004 JOB NAME: Grace/Encinitas CALCULATION NAME: Gracesoilmedian FAULT-DATA-FILE NAME: C:\Program Files\EQFAULTI\cdmgenew(HMR) .dat SITE COORDINATES: SITE LATITUDE: 33 .0592 SITE LONGITUDE: 117.2596 SEARCH RADIUS: 100 mi ATTENUATION RELATION: 23) Abrahamson & Silva (1995b/1997) Horiz. - Soil UNCERTAINTY (M=Median, S=Sigma) : M Number of Sigmas: 0.0 DISTANCE MEASURE: clodis SCOND: 0 Basement Depth: 5.00 km Campbell SSR: Campbell SHR: COMPUTE PEAK HORIZONTAL ACCELERATION FAULT-DATA FILE USED: C:\Program Files\EQFAULTI\cdmgenew(HMR) .dat MINIMUM DEPTH VALUE (km) : 0 .0 --------------- EQFAULT SUMMARY --------------- ----------------------------- DETERMINISTIC SITE PARAMETERS ----------------------------- ------------------------------------------------------------------------------- 1 (ESTIMATED MAX. EARTHQUAKE EVENT APPROXIMATE ------------------------------- ABBREVIATED DISTANCE MAXIMUM I PEAK JEST. SITE FAULT NAME I mi (km) IEARTHQUAKEI SITE ( INTENSITY MAG. (Mw) I ACCEL. g 1MOD.MERC. ROSE CANYON AB Modified trace 6- 1 4 .7 ( 7.6) 1 7.2 1 0.367 1 IX NEWPORT-INGLEWOOD (Offshore) AB 1 11.9 ( 19.1) ) 7.1 1 0.197 1 VIII CORONADO BANK (Mmx Mod. 8-15-03) 1 19.6 ( 31.5) 1 7.6 1 0.159 J VIII ELSINORE-JULIAN 1 26 .1( 42 .0) 1 7.1 1 0.105 1 VII ELSINORE-TEMECULA 1 26 .2 ( 42 .2) 1 6 .8 1 0.093 1 VII SAN JOAQUIN HILLS AB Added 2-9- 1 37 .7 ( 60.6) 1 6 .8 1 0 .084 1 VII EARTHQUAKE VALLEY 1 40 .1 ( 64 .6) 1 6 .5 1 0 .055 1 VI ELSINORE-GLEN IVY 1 40.6 ( 65 .4) 1 6 .8 1 0 .063 1 VI PALOS VERDES 1 42 .3 ( 68 .0) 1 7 .1 0 .070 1 VI SAN JACINTO-ANZA 1 48 .9 ( 78 .7) 1 7 .2 0 .065 1 VI SAN JACINTO-SAN JACINTO VALLEY 1 51.1 ( 82 .2) 1 6 .9 0 .053 1 VI SAN JACINTO-COYOTE CREEK 1 51.4 ( 82 .8) 1 6.8 0 .050 I VI ELSINORE-COYOTE MOUNTAIN 1 52 .4 ( 84 .3) 1 6.8 0 .050 1 VI NEWPORT-INGLEWOOD (L.A.Basin) 1 53 .9 ( 86.8) 1 6.9 0 .051 1 VI CHINO-CENTRAL AVE. (Elsinore) 1 55.6 ( 89.4) 1 6.7 0 .056 1 VI WHITTIER 1 59.1( 95.1) 1 6.8 0 .044 1 VI SAN JACINTO - BORREGO 1 62.4 ( 100.5) 1 6.6 1 0 .038 1 V COMPTON THRUST 1 63 .7 ( 102 .5) 1 6.8 1 0 .052 1 VI SAN JACINTO-SAN BERNARDINO 1 66 .2 ( 106.5) 1 6.7 1 0 .038 1 V ELYSIAN PARK THRUST 1 66 .7 ( 107 .4) 1 6.7 1 0 .047 1 VI SAN ANDREAS - San Bernardino 1 69.1 ( 111.2) 1 7 .3 1 0 .051 1 VI SAN ANDREAS - Southern 1 69.1 ( 111.2) 1 7.4 1 0 .054 1 VI SAN ANDREAS - Coachella 1 75.2 ( 121.0) 1 7.1 1 0 .042 1 VI PINTO MOUNTAIN 1 75.7 ( 121.8) 1 7.0 1 0 .039 1 V SAN JOSE 1 75.9 ( 122 .2) 1 6.5 1 0 .037 1 V SUPERSTITION MTN. (San Jacinto) 1 77.6 ( 124 .9) 1 6.6 1 0.030 1 V CUCAMONGA 1 78.4 ( 126.1) 1 7.0 1 0.048 1 VI SIERRA MADRE 1 78.6 ( 126.5) 1 7.0 1 0.048 1 VI BURNT MTN. 1 79.8 ( 128.4) ) 6.4 1 0 .026 1 V ELMORE RANCH 1 81.4 ( 131.0) 1 6.6 1 0.029 1 V NORTH FRONTAL FAULT ZONE (West) 1 81.9 ( 131.8) 1 7.0 1 0 .046 1 VI SUPERSTITION HILLS (San Jacinto) 1 82.4 ( 132 .6) 1 6.6 1 0.029 1 V EUREKA PEAK 1 82.5 ( 132 .7) 1 6.4 1 0 .025 1 V LAGUNA SALADA 1 83 .1( 133 .7) 1 7.0 1 0 .036 1 V CLEGHORN 1 83 .9( 135.1) 1 6.5 1 0 .026 1 V NORTH FRONTAL FAULT ZONE (East) 1 84 .9( 136.6) 1 6.7 1 0 .037 1 V RAYMOND 1 87.9 ( 141.4) 1 6.5 1 0 .032 1 V SAN ANDREAS - Mojave 1 87.9( 141.4) 1 7.1 1 0.037 1 V SAN ANDREAS - 1857 Rupture 1 87.9( 141.4) 1 7.8 1 0.056 1 VI CLAMSHELL-SAWPIT 1 88.1( 141.8) 1 6.5 1 0.032 1 V VERDUGO 1 90.3 ( 145.4) 1 6.7 1 0.035 1 V LANDERS 1 90.5 ( 145.7) 1 7.3 1 0 .040 1 V BRAWLEY SEISMIC ZONE 1 92 .1( 148.2) 1 6.4 1 0.022 1 IV HOLLYWOOD 1 92.3 ( 148.6) 1 6.4 1 0 .028 1 V HELENDALE - S. LOCKHARDT 1 93 .4 ( 150.3) 1 7.1 1 0 .035 1 V LENWOOD-LOCKHART-OLD WOMAN SPRGSI 96.5 ( 155.3) 1 7.3 1 0.038 1 V SANTA MONICA 1 97.1( 156.2) 1 6.6 1 0 .031 1 V EMERSON So. - COPPER MTN. 1 98.1( 157.9) 1 6.9 1 0 .029 1 V IMPERIAL 1 98.5 ( 158.6) 1 7.0 1 0 .031 1 V JOHNSON VALLEY (Northern) 1 98.9( 159.1) 1 6.7 1 0 .025 1 V MALIBU COAST 1 99.7 ( 160.4) 1 6.7 1 0 .032 1 V -END OF SEARCH- 51 FAULTS FOUND WITHIN THE SPECIFIED SEARCH RADIUS. THE ROSE CANYON AB Modified trace 6- FAULT IS CLOSEST TO THE SITE. IT IS ABOUT 4 .7 MILES (7.6 km) AWAY. LARGEST MAXIMUM-EARTHQUAKE SITE ACCELERATION: 0.3675 g I *********************** * * * E Q F A U L T * * * Version 3 .00 * * *********************** DETERMINISTIC ESTIMATION OF PEAK ACCELERATION FROM DIGITIZED FAULTS JOB NUMBER: 600344-001 DATE: 03-29-2004 JOB NAME: Grace/Encinitas CALCULATION NAME: Gracesoilsigma FAULT-DATA-FILE NAME: C:\Program Files\EQFAULTI\cdmgenew(HMR) .dat SITE COORDINATES: SITE LATITUDE: 33 .0592 SITE LONGITUDE: 117.2596 SEARCH RADIUS: 100 mi ATTENUATION RELATION: 23) Abrahamson & Silva (1995b/1997) Horiz. - Soil UNCERTAINTY (M=Median, S=Sigma) : S Number of Sigmas: 1.0 DISTANCE MEASURE: clodis SCOND: 0 Basement Depth: 5.00 km Campbell SSR: Campbell SHR: COMPUTE PEAK HORIZONTAL ACCELERATION FAULT-DATA FILE USED: C:\Program Files\EQFAULTI\cdmgenew(HMR) .dat MINIMUM DEPTH VALUE (km) : 0.0 --------------- EQFAULT SUMMARY --------------- ----------------------------- DETERMINISTIC SITE PARAMETERS ----------------------------- ------------------------------------------------------------------------------- (ESTIMATED MAX. EARTHQUAKE EVENT I APPROXIMATE 1 ------------------------------- ABBREVIATED I DISTANCE MAXIMUM I PEAK JEST. SITE FAULT NAME I mi (km) (EARTHQUAKE( SITE ( INTENSITY 1 I MAG. (Mw) I ACCEL. g IMOD.MERC. ROSE CANYON AB Modified trace 6- 1 4.7 ( 7.6) 1 7.2 1 0.565 I X NEWPORT-INGLEWOOD (Offshore) AB 1 11.9( 19.1) 1 7.1 1 0.303 1 IX CORONADO BANK (Mmx Mod. 8-15-03) 1 19.6 ( 31.5) 1 7.6 1 0 .245 1 IX ELSINORE-JULIAN 1 26.1( 42 .0) 1 7.1 1 0 .162 1 VIII ELSINORE-TEMECULA 1 26.2 ( 42 .2) 1 6.8 1 0 .146 1 VIII SAN JOAQUIN HILLS AB Added 2-9- 1 37.7 ( 60.6) 1 6.8 1 0 .132 1 VIII EARTHQUAKE VALLEY 1 40.1 ( 64 .6) 1 6.5 1 0.090 1 VII ELSINORE-GLEN IVY 1 40 .6 ( 65.4) 1 6 .8 1 0.099 1 VII PALOS VERDES 1 42 .3 ( 68 .0) 1 7 .1 0 .108 VII SAN JACINTO-ANZA 1 48 .9 ( 78 .7) 1 7 .2 1 0 .100 VII SAN JACINTO-SAN JACINTO VALLEY 1 51.1( 82 .2) 1 6 .9 0 .083 1 VII SAN JACINTO-COYOTE CREEK 1 51.4 ( 82 .8) 1 6.8 0 .080 1 VII ELSINORE-COYOTE MOUNTAIN 1 52 .4 ( 84 .3) 1 6.8 0 .078 1 VII NEWPORT-INGLEWOOD (L.A.Basin) 1 53 .9 ( 86.8) 1 6.9 0.079 1 VII CHINO-CENTRAL AVE. (Elsinore) 1 55 .6 ( 89.4) 1 6.7 0.089 1 VII WHITTIER 1 59.1( 95.1) 1 6 .8 0 .070 VI SAN JACINTO - BORREGO 1 62 .4 ( 100 .5) 1 6.6 1 0 .061 1 VI COMPTON THRUST 1 63 .7 ( 102 .5) 1 6 .8 1 0 .082 1 VII SAN JACINTO-SAN 13ERNARDINO 1 66.2 ( 106.5) 1 6 .7 1 0 .060 1 VI ELYSIAN PARK THRUST 1 66.7 ( 107.4) 1 6.7 1 0 .075 1 VII SAN ANDREAS - San Bernardino 1 69.1 ( 111.2) 1 7.3 0 .078 1 VII SAN ANDREAS - Southern 1 69.1( 111.2) 1 7.4 1 0.083 1 VII SAN ANDREAS - Coachella 1 75.2 ( 121.0) 1 7.1 0.065 1 VI PINTO MOUNTAIN 1 75.7 ( 121.8) 1 7.0 0.061 VI SAN JOSE 1 75.9( 122 .2) 1 6.5 1 0.060 1 VI SUPERSTITION MTN. (San Jacinto) 1 77.6 ( 124 .9) 1 6.6 1 0.049 1 VI CUCAMONGA 1 78 .4 ( 126 .1) 1 7.0 1 0 .074 1 VII SIERRA MADRE 1 78 .6 ( 126.5) 1 7.0 1 0.074 1 VII BURNT MTN. 1 79.8 ( 128 .4) 1 6.4 1 0.043 1 VI ELMORE RANCH 1 81.4 ( 131.0) 1 6.6 1 0.047 1 VI NORTH FRONTAL FAULT ZONE (West) 1 81.9 ( 131.8) 1 7.0 1 0.071 1 VI SUPERSTITION HILLS (San Jacinto) 1 82 .4 ( 132 .6) 1 6.6 1 0.046 1 VI EUREKA PEAK 1 82 .5 ( 132 .7) 1 6.4 1 0.042 1 VI LAGUNA SALADA 1 83 .1 ( 133 .7) 1 7.0 1 0.056 1 VI CLEGHORN 1 83 .9 ( 135.1) 1 6 .5 1 0.043 1 VI NORTH FRONTAL FAULT ZONE (East) 1 84 .9( 136.6) 1 6.7 1 0.060 1 VI RAYMOND 1 87.9 ( 141.4) 1 6.5 1 0.052 1 VI SAN ANDREAS - Mojave 1 87.9 ( 141.4) 1 7 .1 1 0.056 1 VI SAN ANDREAS - 1857 Rupture 1 87.9( 141.4) 1 7 .8 1 0.086 1 VII CLAMSHELL-SAWPIT 1 88.1( 141.8) 1 6 .5 1 0.052 1 VI VERDUGO 1 90.3 ( 145 .4) 1 6 .7 1 0.056 1 VI LANDERS 1 90.5 ( 145.7) 1 7 .3 1 0 .062 1 VI BRAWLEY SEISMIC ZONE 1 92 .1 ( 148 .2) 1 6 .4 1 0.037 1 V HOLLYWOOD 1 92 .3 ( 148 .6) 1 6.4 1 0.047 1 VI HELENDALE - S. LOCKHARDT 1 93 .4 ( 150 .3) 1 7.1 1 0.053 1 VI LENWOOD-LOCKHART-OLD WOMAN SPRGSI 96.5 ( 155.3) 1 7.3 1 0 .059 1 VI SANTA MONICA 1 97.1 ( 156 .2) 1 6 .6 1 0.050 1 VI EMERSON So. - COPPER MTN. 1 98.1 ( 157.9) 1 6.9 1 0 .045 1 VI IMPERIAL 1 98.5 ( 158 .6) 1 7.0 1 0 .048 1 VI JOHNSON VALLEY (Northern) 1 98.9 ( 159.1) 1 6 .7 1 0.041 1 V MALIBU COAST 1 99.7 ( 160.4) 1 6.7 1 0.051 1 VI -END OF SEARCH- 51 FAULTS FOUND WITHIN THE SPECIFIED SEARCH RADIUS. THE ROSE CANYON AB Modified trace 6- FAULT IS CLOSEST TO THE SITE. IT IS ABOUT 4 .7 MILES (7 .6 km) AWAY. LARGEST MAXIMUM-EARTHQUAKE SITE ACCELERATION: 0.5649 g Leighton and Associates,Inc. GENERAL EARTHWORK AND GRADING SPECIFICATIONS Page 1 of 6 LEIGHTON AND ASSOCIATES,INC. GENERAL EARTHWORK AND GRADING SPECIFICATIONS FOR ROUGH GRADING 1.0 General 1.1 Intent: These General Earthwork and Grading Specifications are for the grading and earthwork shown on the approved grading plan(s) and/or indicated in the geotechnical report(s). These Specifications are a part of the recommendations contained in the geotechnical report(s). In case of conflict, the specific recommendations in the geotechnical report shall supersede these more general Specifications. Observations of the earthwork by the project Geotechnical Consultant during the course of grading may result in new or revised recommendations that could supersede these specifications or the recommendations in the geotechnical report(s). 1.2 The Geotechnical Consultant of Record: Prior to commencement of work,the owner shall employ the Geotechnical Consultant of Record (Geotechnical Consultant). The Geotechnical Consultants shall be responsible for reviewing the approved geotechnical report(s)and accepting the adequacy of the preliminary geotechnical findings,conclusions, and recommendations prior to the commencement of the grading. Prior to commencement of grading, the Geotechnical Consultant shall review the "work plan"prepared by the Earthwork Contractor(Contractor)and schedule sufficient personnel to perform the appropriate level of observation,mapping,and compaction testing. During the grading and earthwork operations,the Geotechnical Consultant shall observe, map, and document the subsurface exposures to verify the geotechnical design assumptions. If the observed conditions are found to be significantly different than the interpreted assumptions during the design phase,the Geotechnical Consultant shall inform the owner, recommend appropriate changes in design to accommodate the observed conditions, and notify the review agency where required. Subsurface areas to be geotechnically observed,mapped,elevations recorded,and/or tested include natural ground after it has been cleared for receiving fill but before fill is placed,bottoms of all "remedial removal"areas,all key bottoms,and benches made on sloping ground to receive fill. The Geotechnical Consultant shall observe the moisture-conditioningand processing of the subgrade and fill materials and perform relative compaction testing of fill to determine the attained level of compaction. The Geotechnical Consultant shall provide the test results to the owner and the Contractor on a routine and frequent basis. 3030.1094 Leighton and Associates,Itic. GENERAL EARTHWORK AND GRADING SPECIFICATIONS Page 2 of 6 1.3 The Earthwork Contractor: The Earthwork Contractor (Contractor) shall be qualified, experienced, and knowledgeable in earthwork logistics, preparation and processing of ground to receive fill, moisture-conditioningand processing of fill, and compacting fill. The Contractor shall review and accept the plans, geotechnical report(s), and these Specifications prior to commencement of grading. The Contractor shall be solely responsible for performing the grading in accordance with the plans and specifications. The Contractor shall prepare and submit to the owner and the Geotechnical Consultant a work plan that indicates the sequence of earthwork grading, the number of "spreads" of work and the estimated quantities of daily earthwork contemplated for the site prior to commencement of grading. The Contractor shall inform the owner and the Geotechnical Consultant of changes in work schedules and updates to the work plan at least 24 hours in advance of such changes so that appropriate observations and tests can be planned and accomplished. The Contractor shall not assume that the Geotechnical Consultant is aware of all grading operations. The Contractor shall have the sole responsibility to provide adequate equipment and methods to accomplish the earthwork in accordance with the applicable grading codes and agency ordinances, these Specifications, and the recommendations in the approved geotechnical report(s) and grading plan(s). If, in the opinion of the Geotechnical Consultant,unsatisfactory conditions,such as unsuitable soil, improper moisture condition, inadequate compaction,insufficient buttress key size,adverse weather,etc.,are resulting in a quality of work less than required in these specifications,the Geotechnical Consultant shall reject the work and may recommend to the owner that construction be stopped until the conditions are rectified. 2.0 Preparation of Areas to be Filled 2.1 Clearing and Grubbing: Vegetation, such as brush, grass, roots, and other deleterious material shall be sufficiently removed and properly disposed of in a method acceptable to the owner,governing agencies,and the Geotechnical Consultant. The Geotechnical Consultant shall evaluate the extent of these removals depending on specific site conditions. Earth fill material shall not contain more than I percent of organic materials (by volume). No fill lift shall contain more than 5 percent of organic matter. Nesting of the organic materials shall not be allowed. If potentially hazardous materials are encountered,the Contractor shall stop work in the affected area,and a hazardous material specialist shall be informed immediately for proper evaluation and handling of these materials prior to continuingto work in that area. As presently defined by the State of California,most refined petroleum products(gasoline, diesel fuel, motor oil, grease,coolant,etc.)have chemical constituents that are considered to be hazardous waste. As such, the indiscriminate dumping or spillage of these fluids onto the ground may constitute a misdemeanor,punishable by fines and/or imprisonment, and shall not be allowed. 3030.1094 Leighton and Associates,Inc. GENERAL EARTf RVORK AND GRADING SPECIFICATIONS Page 3 of 6 2.2 Processing: Existing ground that has been declared satisfactory for support of fill by the Geotechnical Consultant shall be scarified to a minimum depth of 6 inches. Existing ground that is not satisfactory shall be overexcavated as specified in the following section. Scarification shall continue until soils are broken down and free of large clay lumps or clods and the working surface is reasonably uniform,flat, and free of uneven features that would inhibit uniform compaction. 2.3 Overexcavation: In addition to removals and overexcavations recommended in the approved geotechnical report(s) and the grading plan, soft, loose, dry, saturated, spongy, organic-rich, highly fractured or otherwise unsuitable ground shall be overexcavated to competent ground as evaluated by the Geotechnical Consultant during grading. 2.4 Benching: Where fills are to be placed on ground with slopes steeper than 5:1 (horizontal to vertical units),the ground shall be stepped or benched. Please see the Standard Details for a graphic illustration. The lowest bench or key shall be a minimum of 15 feet wide and at least 2 feet deep, into competent material as evaluated by the Geotechnical Consultant. Other benches shall be excavated a minimum height of 4 feet into competent material or as otherwise recommended by the Geotechnical Consultant. Fill placed on ground sloping flatter than 5:1 shall also be benched or otherwise overexcavated to provide a flat subgrade for the fill. 2.5 Evaluation/Acceptance of Fill Areas: All areas to receive fill, including removal and processed areas, key bottoms, and benches, shall be observed, mapped, elevations recorded,and/or tested prior to being accepted by the Geotechnical Consultant as suitable to receive fill. The Contractor shall obtain a written acceptance from the Geotechnical Consultant prior to fill placement. A licensed surveyor shall provide the survey control for determining elevations of processed areas,keys,and benches. 3.0 Fill Material 3.1 General: Material to be used as fill shall be essentially free of organic matter and other deleterious substances evaluated and accepted by the Geotechnical Consultant prior to placement. Soils of poor quality, such as those with unacceptable gradation, high expansion potential,or low strength shall be placed in areas acceptable to the Geotechnical Consultantor mixed with other soils to achieve satisfactory fill material. 3.2 Oversize: Oversize material defined as rock,or other irreducible material with a maximum dimension greater than 8 inches, shall not be buried or placed in fill unless location, materials, and placement methods are specifically accepted by the Geotechnical Consultant. Placement operations shall be such that nesting of oversized material does not occur and such that oversize material is completely surrounded by compacted or densified fill. Oversize material shall not be placed within 10 vertical feet of finish grade or within 2 feet of future utilities or underground construction. 3030.1094 i Leighton and Associates,Inc. GENERAL EARTHWORKAND GRADING SPECIFICATIONS Page 4 of 6 3.3 Import: If importing of fill material is required for grading,proposed import material shall meet the requirements of Section 3.1. The potential import source shall be given to the Geotechnical Consultant at least 48 hours(2 working days)before importing begins so that its suitability can be determined and appropriate tests performed. 4.0 Fill Placement and Compaction 4.1 Fill Lam: Approved fill material shall be placed in areas prepared to receive fill (per Section 3.0) in near-horizontal layers not exceeding 8 inches in loose thickness. The Geotechnical Consultant may accept thicker layers if testing indicates the grading procedures can adequately compact the thicker layers. Each layer shall be spread evenly and mixed thoroughly to attain relative uniformity of material and moisture throughout. 4.2 Fill Moisture Conditioning: Fill soils shall be watered,dried back, blended,and/or mixed, as necessary to attain a relatively uniform moisture content at or slightly over optimum. Maximum density and optimum soil moisture content tests shall be performed in accordance with the American Society of Testing and Materials (ASTM Test Method D1557-91). 4.3 Compaction of Fill: After each layer has been moisture-conditioned, mixed, and evenly spread,it shall be uniformly compacted to not less than 90 percent of maximum dry density (ASTM Test Method D1557-91). Compaction equipment shall be adequately sized and be either specifically designed for soil compaction or of proven reliability to efficiently achieve the specified level of compaction with uniformity. 4.4 Compaction of Fill Slopes: In addition to normal compaction procedures specified above, compaction of slopes shall be accomplished by backrolling of slopes with sheepsfoot rollers at increments of 3 to 4 feet in fill elevation, or by other methods producing satisfactory results acceptable to the Geotechnical Consultant. Upon completion of grading,relative compaction of the fill,out to the slope face, shall be at least 90 percent of maximum density per ASTM Test Method D 1557-91. 4.5 Compaction Testing: Field tests for moisture content and relative compaction of the fill soils shall be performed by the Geotechnical Consultant. Location and frequency of tests shall be at the Consultant's discretion based on field conditions encountered. Compaction test locations will not necessarily be selected on a random basis. Test locations shall be selected to verify adequacy of compaction levels in areas that are judged to be prone to inadequate compaction(such as close to slope faces and at the fill/bedrock benches). 3030.1094 Leighton and Associates,Inc. GENERAL EARTHWORK AND GRADING SPECIFICATIONS Page 5 of 6 4.6 Frequency of Compaction Testing: Tests shall be taken at intervals not exceeding 2 feet in vertical rise and/or 1,000 cubic yards of compacted till soils embankment. In addition,as a guideline,at least one test shall be taken on slope faces for each 5,000 square feet of slope face and/or each 10 feet of vertical height of slope. The Contractor shall assure that fill construction is such that the testing schedule can be accomplished by the Geotechnical Consultant. The Contractor shall stop or slow down the earthwork construction if these minimum standards are not met. 4.7 Compaction Test Locations: The Geotechnical Consultant shall document the approximate elevation and horizontal coordinates of each test location. The Contractor shall coordinate with the project surveyor to assure that sufficient grade stakes are established so that the Geotechnical Consultant can determine the test locations with sufficient accuracy. At a minimum,two grade stakes within a horizontal distance of 100 feet and vertically less than 5 feet apart from potential test locations shal I be provided. 5.0 Subdrain Installation Subdrain systems shall be installed in accordance with the approved geotechnical report(s), the grading plan, and the Standard Details. The Geotechnical Consultant may recommend additional subdrains and/or changes in subdrain extent, location, grade, or material depending on conditions encountered during grading. All subdrains shall be surveyed by a land surveyor/civil engineer for line and grade after installation and prior to burial. Sufficient time should be allowed by the Contractor for these surveys. 6.0 Excavation Excavations, as well as over-excavation for remedial purposes, shall be evaluated by the Geotechnical Consultant during grading. Remedial removal depths shown on geotechnical plans are estimates only. The actual extent of removal shall be determined by the Geotechnical Consultant based on the field evaluation of exposed conditions during grading. Where fill-over-cut slopes are to be graded,the cut portion of the slope shall be made, evaluated,and accepted by the Geotechnical Consultant prior to placement of materials for construction of the fill portion of the slope,unless otherwise recommended by the Geotechnical Consultant. 3030.1094 Leighton and Associates,Inc. GENERAL EARTHWORK AND GRADING SPECIFICATIONS Page 6 of 6 7.0 Trench Backfills 7.1 The Contractor shall follow all OHSA and Cal/OSHA requirements for safety of trench _ excavations. 7.2 All bedding and backfill of utility trenches shall be done in accordance with the applicable provisions of Standard Specifications of Public Works Construction. Bedding material shall have a Sand Equivalent greater than 30 (SE>30). The bedding shall be placed to 1 foot over the top of the conduit and densified by jetting. Backfill shall be placed and densified to a minimum of 90 percent of maximum from 1 foot above the top of the conduit to the surface. 7.3 The jetting of the bedding around the conduits shall be observed by the Geotechnical Consultant. 7.4 The Geotechnical Consultant shall test the trench backfill for relative compaction. At least one test should be made for every 300 feet of trench and 2 feet of fill. 7.5 Lift thickness of trench backfill shall not exceed those allowed in the Standard Specifications of Public Works Construction unless the Contractor can demonstrate to the Geotechnical Consultant that the fill lift can be compacted to the minimum relative compaction by his alternative equipment and method. 3030.1094 I FILL SLOPE -------------------- -_------------------------ -=COM- ACTEa-- _=-FILL=__�_' _ PROJECTED PLANE _______________ _ --_---- -- 1 TO 1 MAXIMUM FROM - TOE OF SLOPE TO - APPROVED GROUND REMOVE EXISTING UNSUITABLE GROUND SURFACE _ ________________ BENCH BENCH HEIGHT MATERIAL - --- - --- - 4' TYPICAL 15' MIN. 2' MIN. LOWEST KEY BENCH DEPTH (KEY) FILL-OVER-CUT SLOPE _ "-7-7 EXISTING GROUND SURFACE _- � _ _ _ _ _ � - � - , ' � ^ - ' FINISH GRADE • OVERSIZE ROCK IS LARGER THAN - - 8 INCHES IN LARGEST DIMENSION. • EXCAVATE A TRENCH IN THE COMPACTED FILL DEEP ENOUGH TO BURY ALL THE GRANULAR MATERIAL TO BE ROCK. DENSIFIED IN PLACE BY DETAIL • BACKFILL WITH GRANULAR SOIL JETTED FLOODING OR JETTING. OR FLOODED IN PLACE TO FILL ALL THE * DO NOT BURY ROCK WITHIN 10 FEET OF FINISH GRADE. • WINDROW OF BURIED ROCK SHALL BE PARALLEL TO THE FINISHED SLOPE. GRANULAR MATERIAL TYPICAL PROFILE ALONG WINDROW GENERAL EARTHWORK AND OVERSIZE GRADING SPECIFICATIONS ROCK DISPOSAL STANDARD DETAILS B LEIGHTON AND ASSOCIATES `EXISTING \ GROUND SURFACE -- ===- =--==----===--=---="=--=- -_-_-=- _ -7 - - - - --- -- - -_ - -_ _ - - ---_- -_ - - - _ _ ____________ _ _--___ _-__ __ _--_- -_=-- --=-_-_-' --------- -:=----=-COMPACTED FILL=-`_-__ -----------7------="=------ --=--=----=-=--=--_-__ _ --7--- ---------- -------------------------- - ----- --- - ________ _______ _________________= r==- - - -_- -_ - --______________________________ -----=- - --=--=---- -- -=------ � ' _ � — _ � _ _ ' , _ OUTLET PIPES - 100' MAX. O.C. HORIZONTALLY, = BENCH -7 SEE SUBDRAIN TRENCH KEY WIDTH AS NOTED ON GRADING PLANS 12" MIN. OVERLAP— KEY DEPTH (15' MIN.) FROM THE TOP HOG (2- MIN ) RING TIED EVERY FOR COLLECTOR PIPE TO OUTLET PIPE CALTRANS CLASS 11 PERMEABLE OR #2 WRAPPED IN FILTER 6" MIN. FABRIC COVER N–PERFORAT PERFORATED 0 PIPE BEDDING PROVIDE POSITIVE FILTER FABRIC SEAL AT THE ENVELOPE (MIRAFI JOINT 140 OR APPROVED SUBDRAIN TRENCH DETAIL SUBDRAIN INSTALLATION subdrain collector pipe shall be installed with perforotion down or, unless otherwise designated by the geotechnicol consultant. Outlet pipes shall be non–perforoted pipe. The subdroin pipe shall hove at least 8 perforations uniformly spaced per foot. Perforation shall be 1/4" to 1/2" if drill holes are used. All subdroin pipes shall have a gradient of at least 2% towards the outlet. SUBDRAIN PIPE – Subdroin pipe shall be ASTM D2751, SDR 23.5 or ASTM D1527, Schedule 40, or ASTM D3034, SDR 23.5, Schedule 40 Polyvinyl Chloride Plastic (PVC) pipe. All outlet pipe shall be placed in a trench no wide than twice the subdroin pipe. Pipe shall be in soil of SE >/=30 jetted or flooded in place except for the outside 5 feet which shall be native soil backfill. BUTTRESS OR GENERAL EARTHWORK AND REPLACEMENT FILL GRADING SPECIFICATIONS STANDARD DETAILS D SUBDRAINS � _ _ _ -- _ _ _ ., - - � _ - _ -~ SOIL BACKFILL, COMPACTED TO 90 PERCENT RELATIVE COMPACTION BASED ON ASTM D1557 MrNb WALL WATERPROOFING OVERLAP FILTER FABRIC ENVELOPE 0 0. (MIRAFI 140N OR APPROVED PER ARCHITECT'S 0 EQUIVALENT).* SPECIFICATIONS 0 FINISH GRADE (MIN.) DIAMETER PERFORATED 0 PVC PIPE (SCHEDULE 40 OR EQUIVALENT) WITH PERFORATIONS -------------- ORIENTED DOWN AS DEPICTED MINIMUM 1 PERCENT GRADIENT z4o .0 0 WALL FOOTING COMPETENT BEDROCK OR MATERIAL JATED BY THE GEOTECHNICAL CONSULTANT NOTE: UPON REVIEW BY THE GEOTECHNICAL CONSULTANT, COMPOSITE DRAINAGE PRODUCTS SUCH AS MIRADRAIN OR J-DRAIN MAY BE USED AS AN ALTERNATIVE TO GRAVEL OR CLASS 2 PERMEABLE MATERIAL. INSTALLATION SHOULD BE PERFORMED IN ACCORDANCE WITH MANUFACTURER'S RETAINING WALL GENERAL EARTHWORK AND GRADING SPECIFICATIONS DRAINAGE DETAIL STANDARD DETAILS E LEIGHTON AND ASSOCIATES - __ _= GEOTECHNICAL MAP TENTATIVE A NO . � =-_ -- - � -__ �� - �—� LOTS 4 AND 5 OF GARDEN VIEW PLAZA ENCINITAS, CALIFORNIA GARDEN VIEW OFFICE BUILDING �,g�_ --- o „_ , _ Proj: 600344-00 1 Scale. 1 -20 Date: 4/2/04 C lS� U NE —� _ — —— n —59 — � = Eng/Geol: WDO/RKW I Drafted By: BQT CP By: BQT — _� CON E E W _E. � o - - JOIN �("}, _ - - — Leighton Consulting, Inc. Path: P:/Drafting/600344/011/OF_4-2-04/PLATEI EXIST. VNC TE W V T \� O ATCH QL-YS� 1 --0 L � R_MGX NGRWP tOM y -� ( OOTG °7" _ _ PLATE 1 - SI — ` LEGEND W 0 5 WAL . ' c � I � _ - _ , � � II � I I � � Af0 ARTIFICIAL OLDER FILL 06 Tt TORREY SANDSTONE c� Z x f O 6' & CUT E �TYP. / � '� �o� oBS_[�9REDL tJ - o _UL,1 , APPROXIMATE LIMITS OF FILL 67.5= - Tt / E II n /�° I 7.fK1 W 79. 167.5 , Co T T _ 1 Ii Tt� i °� o - o Z. O L ��.� IE E ER I TOR — ' ._ ' i � n A H�NaA WALL p�E _`T D j � I 7 � �� K Y ON WALL- R ;1=LENT — — -- - '" - -� _ - - - �� 0 = �� 9 � X�o A � w L� PEDESTRIAN x Co �� l 24 D SUB RAMP -� O � 74:401 G HIN i7� li.��- , �li 1 (� T L., Q v. CT Y U - � :; i , i ..--.�xi- . -. . -... �a-- .,. ��, --, _.� -._. _�_,._ _.__ ''� 1.•..v �.vry�..._ . _ - ---___—__- _ _--- ---__ - �� ,�1. TAININ WALL OFFIC_ 3U1 !- � :! I 20 10 0 20 40 60\Tff 0" CURB � � � � L - EE I] � �; EE1 5. 9 ExIATIN R AININ v Q O 6 �e c TER C D= 7, F I V A __0 SCALE IN FEET 1 inch = 20 ft. C\ I n ! I P 78.0"1 N L F- x�` P DESTRI 77. W � w i RA P C .5'-WALL II L ND PE DR -1 �. W I �I CO SCALE C, 0 � . � � t;!_ �� -s ue sU IVISION� 160' BI S=LE� I ©0.5' Tt iirnr l.� O �� BOU DAR T R L EVE) �TI I HI HI i IiLUi l 0 ��, 7 I RECOMMENDED �i' � � A � � �� [6' " cue STS , i�� \ � � � I LIMITS OFI CURB MAXL ITT. o / W TR TR a Gl1�S _ ` a . o OVEREXCAVAT�ON �: x LEGEND T 1 INT - - - x Q0 X - I. PROPOSED EXISTING Cni ll� 4� - i I I -1 I; 00 o > > 1 I O WATER SERVICE . z 0 o ! I I I I I r x C -{w GUY POLE ANCHOR —GA 0 00 14� FIRE SERVICE �Q POWER POLE . . . {®} PP > C �° 24" GATOLI .T I O Tt SEWER LATERAL . r 6 C —� ELECTRIC LINE . E o \\ \ r17,T50TC ,_ CE3 T_ ASPHALT PAVEMENT 1 — G t � � 1171 001E CJ1- � S � � 18 .5 W _ � � I� � � ® GAS LINE _ . Q NEW SS g.qB I CONCRETE PAVEMENT _ 0 STORM DRAIN LINE . . . . . . . . . . —SD ALL ( _OTW DDCVA . . . . . . . . . . . . . . . . . @�® SEWER MANHOLE . . . . . . . . . . . � SMH X66 OTW f �° E v T 18 ..oFS STORM DRAIN . �� . SEWER LINE . . . . . . . . . . . . . .— S - o 0 WATER SERVICE LINE. . . . . . . . . . . . — — -- I _W_ WATER LINE . — W— �I� LINE. .. .. —S WATER VALVE _ _ O WV . 0-) 6 �, e o - - - ® WATER METER . . . . . . . . . . . . �W SEWER �- � RETAINING WALL SPOT ELEVATION . . . �9 6" CURB & GUTTER. . . . . . . . . . . . X 167.6 SPOT ELEVATION . . . . . . . . . . . . 16" SLOTTED CURB & GUTTER . . . . . . _ — — CIVIL ENGINEER N9� �J� 3G I �L -- - -� '_ � 24" CONIC. CATCH BASIN. . . . . . . . . . . III _ - - - -- —I — — -- -- — FLOW LINE . . . . _ . . . . . . . . . . . . bUf kett � 178.9TC Z �- SUB VISION E T �p� ' TC 65 Tv � EXI WATER BOU DARY GAS LINE SPOT ELEVATION �— & Yd ® n g a n0 4' JIDE RIP R P M=ER TO RE AIN N J' ^RE CONTOUR LINE 178 40 S 52 OIE V� EN RGY DI SI ATOR S ,i�CE _ �// \ _ engineers & surveyors ORMDRA I� _ ` ` ` " I E 0 3434 fourth ave. San diego ca. / zl- I T L ! / / I J S PAC 921 03-4911 * 619 299-5550 FcT o E TI � Z H - `O _ _ Prepared By. _ f - - ` ax (619)_ 299-9934' ol- p =S \ O� I Name: BURKETT & WONG Revision 14: Structural & Civil Engineers and Surveyors �I 10"PVC W - W N W 3434' Fourth Ave. Revision 13: o 0 n t a! z o _ d W W Address: Revision 12: O _ _ _-_ -W W a � Q0 San Qiego, CA. 92103-4941 W Phone #: (619) 299-5550 Fax (619) 299-9934 Revision 11: 0 FT Revision 10: _ Project Address; ° _ -- - -- - -- _ - - - - Revision 9: O Q - ® - - - Revision 8: _ I � _ _ I 700-720 GARDEN VIEW COURT Revision 7: VICINITY MAP EASEMENTS ENCINITAS, ca Revision Revision 5: : NO SCALE OWNER/SUBDIVIDER: ABUTTER'S RIGHTS OF INGRESS AND EGRESS TO OR FROM GARDEN VIEW ROAD Revision 4: LEUCaDIA BLVD ADJACENT THERETO HAVE BEEN DEDICATED OR RELINQUISHED ON THE FILED MAP. Project Name: OLIVENHAIN RD ReVISIOn 3: GRACE PARTNERS, LLC 7O A STRIP OF LAN 8.00 FEET WIDE LYING WITHIN SAID LOT 5, LYING ADJACENT TO AND GARDEN VIEW OFFICE BUILDING 9 Revision 2: S11 W COINCIDENT WITH THE EXTERIOR BOUNDARY OF THAT CERTAIN ROADWAY SHOWN AS "GARDEN 0 617 SAXONY PLACE, SUITE 104 Revision 1: a"3' ENCINITAS CA 92024 VIEW COURT" ON MAP NO. 11909. PER EASEMENT GRANTED TO SAN DIEGO GAS & ELECTRIC, - - Q(tOFESS1 GARDEN VIEW RD. RECORDED SEPT. 22, 1989 AS DOCUMENT NO. 89-512677 O.R. IN THE OFFICE OF THE COUNTY �� 6 A. A�F a TE. (760}436-3297 `F t R 12/22/03 T T RECORDER OF SAN DIEGO h �� 90 y Original Date: ENCINITAS _°z SITE LEGAL DESCRIPTION ® 3.0 FOOT WIDE BROW DITCH BEGINNING AT THE SOUTHWEST CORNER OF LOT 5 AND ENDING � i � � Sheet Title AT THE NORTHEAST CORNER OF LOT 10. AS DOCUMENT NO. 1993-0239404 O.R. No. 64472 TENTATIVE MAP/GRADING PLAN Sheet 1 of 2 C.) MOUNTAIN VISTA DR. LOTS= 4 AND 5 OF CITY OF ENCINITAS NO. 4255, IN THE CITY OF ENCINITAS, RECORDED APRIL 19, 1993 IN THE OFFICE OF THE COUNTY RECORDER * Ex 06-30-07 vt BY: w COUNTY OF SAN DIEGO, STATE OF CALIFORNIA, ACCORDING TO MAP O THE PRIVILEGE AND RIGHT TO EXTEND DRAINAGE STRUCTURES AND EXCAVATION AND s P CHRISTIE A. RADDER R.C.E. 64472 DEP ENCINITAS BLVD ENCINITAS BLVD THEREOF' NO. 11909, FILED IN THE OFFICE OF THE COUNTY RECORDER OF EMBANKMENT SLOPES BEYOND THE LIMITS OF GARDEN VIEW RD. WHERE REQUIRED FOR THE Tq�. CIVIL. �O�P EXP. 06/30/07 # SAN DIEGO COUNTY, OCTOBER 1, 1987. CONSTRUCTION AND MAINTENANCE OF SAID ROAD AS CONTAINED IN THE DEED RECORDED NOV. FOF C B&W JOB NO. 8404U 24, 1982 AS FILE NO. 82-363385 OFFICIAL RECORDS (NOT PLOTABLE). 6" 4'-4" Lo - 9 �[ / GEOMEMBRANF PER SOIL ENGINEER - JOIN EXIST_ _ _ _ RECOMMENDATIONS. MEMBRANE SHOULD � � 1 � I _��- �� - "� o� _ _ �_-� ____ � � ca _ �_ --�� BROW DITCH ��p -- 8" BELOW GROUND ELEVATION -��_ �_ FL 162.48 _��- 645 _ 9� ro RE "B" BROW (INSTALL PER MANUFACTURER'S GUIDELINE - n �o 0849"W X1.0 _ - - - o D H PER D-75 � Lq PRIVATE VEGETATED SWALE SECTION NOT TO SCALE FOR BMP: 7S TO BE PRIVATELY MAINTAINED AND NOT TO BE MODIFIED WITHOUT A PERMIT FROM THE CITY OF ENCINITAS. T �- �� 67 0 -- V - CTION m 9 z C 178.67TW a 176.007E - x co N01. - _ _ ! 29.34'-18" F - - �� > - OEl o J wl �@' 29.2% - AN m 1 431E 4.001E GRAPHIC SCALE � � :� � - sCM I 20 o ao .33 RIM I I - I - - _ _ n ---- _ �' � ! .: I 136.93 INV i � I � _•- e „� _ 'v 1 .86FI ::i 1!i ' In I ,B.'% �1I 'I � I --- 6i ---- If i --- - i 1 75.0 F 0 c ',., I 3OOTG 0 0 � I 331E �. _� L o - i 1 inch = 20 ft : . . _e i '-6..;;r- , I E .. ,.; �. _ _� � I ,: � t _ ,.-� --- - �, ��I FESS P: OWED TRtN 'H o ° i K&S ENGINEERING QRa �N r I I I. , ,I� o 8.0331 VV �� S 9l �SURFACINO PE 1 r. NO 55 T --- g Z I 155 ,g8.67T RED�STRIPINC SIRE LANE" �o N n PARKING FIRE LANE° 7 130 I i ,8.00:F 3 PaG01,G Engineering SUrVR �".0 P� Sy CITY OF ENCINIT I F NO PAR STANDARD 68.04: L ' 6 -"NO PARKING FIRE LANE RED STRIPING No_ 48592 n RED STRIPING 8 748 75.85 s CONST EX. BLDG. exP s/3oLoe I �I - i 469.40 I < 225 i 3 nT96-0565 7801 Mission Center Court; Suite 7G s, wI �e I I = Q 18 ° 72.28 �� I I�w �I 9 v6. ' _ SOIL Diego Co. 92108 VTFOFCALAFUG + � .4 �� ' '� � � i I �� I o{� i °' i I I: - g _ m 78.00/178.68TF 186.67 TJJ �` 55.77 6�" C - 75. 17 . 2 SDR-35 (c .7% � ° I 16� ` � 172 39 I 17 . 9 � Y r 1 ss 971- 0 172.56 I WALLED TRASH STORAGE ? �_ � 1729 � � 172.061E � � � 176.94 � I � I � � it CONTAINS WITH LIDS 3 - n A 5' C' AR� � 17273 a>x � � -_- I '_. � - _ ��`' I � - • � � _ Q) III it BFI II gym„ j =1 II 176oa 1. z i so% �j I� MINIM IX � z I _�- 29 w- 2° C.B. �< �r 173.0 � �' oc 5t J' 174.87TG � 173.25 X 173.371E m 18 76 50:G 76.001E 78.6 1178.677E 3.93'6°PVC 5 72.73 0 X172.831 - - � I SDR-35 @ 9.5% _ 2" STAIRS -- - - - : c 173.09` _ >o _ TONE �.. r .J RE�rAINING WALL I C . � � I� 73.231E 1 0" CU I L I FACE 8 7 �� < �' EX. PARKING 68.67 168 001W I P A� 3 I 175 00 < _ CARS �n 57.33TF r I 77.30FL BIN-� 8 5 L I I I I NO PARKING FIRE LAiNE" 175.4271 12: C.B S m OT RED STRIPING 71.75 �� 74.92TG `D 81 72.85 _ 8 1 i I - a MASO R E�AINI G 73.531E 186.88' 15"PVC Off° { WALL R SD 5.0 SDR-35 @ 1.0% I � - 175.4 T I 1 _ � �, f 178 66 W � Id ° i � -MODIFIED B' ( � 71.75 74 JG'F s BROW CH I � I F� 177.94TC 18 .19 ( ' 2", D=6" j� 172.64 I _ 75 00 ; cg 5- _ _ - 18' _ .�. �. �- X RETAINING WALL - o 2.28 2% I I 5.14 I 11973, 6„py . 104 2,ry6,•p 1. % i2" C r3 1 RED STRIPING SD 5 ® 1. I ' R!' I "NO PARKING NE LANE" .06F 2.15, - V J �7 66 1793 TW I A 174 00 F �� < 186.00 /185.33TW 1 + r; 1L` �% 5� - - _ °� 179.34TF ! fn �LIPI A . PR XIMATE 7 00 EDP XCAVATION C B �� ..�I li MASONRY RETAINING ('' WALL PEP, S Rt3l.TGRAL t ' . i � � . IRE RIS R I I� I � 17 2TC ` '1' 'I I I� r� n rr ENGINE=R CAL„JL„TIONS ° 7 E �� - ASONRY RETAINING 175 1 I I x OOTW / -�- I � -- WALL PER STRUCTURAL �� h 1 7/1620 F - �� ENGINEER CALCULATIONS I 1 _ I X "NO PARKING FIRE LANE' , _ 179.33180.00T I�,�4 .I o, i O _ } x 174 OoT -I I 6 RED STRIPING W [S6 N� 70 4 1 60.02 RIM I 36' C. / - _ I.� 1 � o TEN!PORARY 1747/TG n 1 .9"G _ C l O'dERREAD cF'r I I �X 2 RCP II JI -A 2. 11E "NO PARKi dE" I ; - < �J< J lJ ELEC. 1 T - I^ �s 67. 7 F V R Too I ° U { - 0 180.67 W r _ - 5% ED NG - yL - - _ v1s`8 -GB 1 � s Jl , I �. / ° - r � i 181 21 G 79.9_6_ 5.0% RO.00T yIi � i _ �L2Z4^-15'P�I .. ,,.-, 'i iG- II•; "I .;i ZI�I'I YII ' � "` � -, .✓/� - Y ~_ \� �?.G011r - SDfv1 SDR-35 @ 2kI v0.94 17 .24FS y 66.55 / 175.001 .. 161.29 1 x _ b-4x6 I 67 h 7 e 175.00 - V = L. ( 69.96 3%� 75 001 �i irl 7) 0 °� s G� �IJ - -- -x 14, �- � �l - '� ° _164311E AONUMENT SIGN PER /�� 1 � I .� : iI tj 620CIt �a -� � � �-_ 87.84 °P'J MRG6TEC�lRAL PLANS LEGEND I � � � : �v / \ �7 - _ _ �� _ RED STRIPING n SMH �� F -� _ - "NO PARKING F 'E" 162.35 RI 70 4 /�f0 ARTIFICIAL OLDER FILL \ _ -° 45, - - _ o N 1°�s'z3°U 170.00' . 52.73 v sTRaICH N� owAL L 0 I ' TYPE "B'; PER d �� ! N 1°15'23"W -SCROD 1-32 4 LE_ 16E.1 Tt TORREY SANDSTONE I I � I � � _��_ I _ON � � °° - J G a � �� 25 RIVEWAY o ST F, EX 4" PVC EX WATER E . UNDER METER EX. SDI � o STRAIG HEA WALL P�RrSCRSD G-14A VAULTS _ rn N T 30' DRIVEWAY RISERS TO BE M TER RAIN EX. SDG E EX. SDG&E PROPOSED T NCH ° s APPROXIMATE LIMITS OF FILL S YPE 'e" PER o RELOCATED �, f / RISERS VAULTS o D B 1 LET I SDR- D-32 ER SDRSD G-14A N s RESU �FACIN PER a ROPOSED TRENCH- + ^ s CITY OF EN INITAS o v 16 RIM /// EX. 4' SEWER / o _ SINKH _E TO BE RE PAIRED / RESURFACING PE STANDARD C �■m m m m■jCs APPROXIMATE LOCATION OF CROSS SECTION I 1 INV I v AND EPAVED T T E SATIS ACTIO CITY OF ENCINITA LA ERAL 4+00 I 5 oo = STANDARD 3+F0 EXISTIN�8"PVC SEW R _ S. EXISTING SMN o I OF CITY'S INSPECTO _ S LINE Na 09-1 20 o - - -S S 1 I �.,� SMH 184.27 RIM _ 2°' B DATA D RD ' Vim fv D U , T �_ 00 D No. 09-1615 2+00 PROPOSED T ENCH NEW 6' EWER U) EX. 4° SE ER RESURFACING ER ATERAL EE DA W W - _w - - w CD 4 06 RIM RE SERVICE _ LATERAL TY OF ENCiNI AS TABLE ON SHEET 2 _W p 156.19 INV �� a W W � o PLATE 1 s S NDARDw Uv w V EX. WATER w a" FI E SERVICE z �'� - , Ex. wA7 � LATERAL L A GEOTECHNICAL MAP z w 1 NLET - - - LATERAL o LOTS 4 AND 5 OF GARDEN VIEW PLAZA � ENCINITAS, CALIFORNIA lj C) Proj: 600344-001 Scale: 1 "=20' Date: 1/7/057 `� Eng/Geol: WDO/RKW Drafted By: BQT CP By: BQT ___- ` w I � _ I / , O�v I �/ � � �� z Leighton Consulting, Inc. PADRAFTING\600344\001\OF 1-6-05\PLATEI.DWG(01-07-05 10:56:04AM) Plotted,by:jstrege OUP COW. Y in REVISION APPROVED DATE REFERENCES DATE BENCHMARK SCALE COMMUNITY DEVELOPMENT DESIGNED BY: DRAWN BY: CHECKED BY: o C.M.D. G.M.D. K.ss. APPROVALS CITY OF ENCINITAS ENGINEERING DEPARTMENT DRAWING NO. DESCRIPTION: WELL MONUMENT REVIEWED BY: PLANS PREPARED UNDER SUPERVISION OF: RECOMMENED APPROVED GRADING AND IMPROVEMENT PLAN FOR: ELEVATION ON BRASS DISK HORIZONTAL: -20' DATE CENTERLINE OF EL CAMINO REAL & BY: BY: GARDEN V I E W OFFICE Z BUILDING 91 8 3- G w ENCINITAS BLVD, RECORDS OF 48592 z THE COUNTY OF SAN DIEGO VERTICAL N/A KAMAL S. SWEIS R.C.E- NO. 06-30-2006 DATE: DATE: LOTS 4 SG 5 OF ENCINITAS TRACT 4255 ELEV. 220.79 M.S.L. DATE EXP. CASE NO. 03-253 SHEET 3 OF 5 Y tn