Loading...
2002-7533 G Conway & Associates, Inc. Civil Engineers/Surveyors/General-Engineering Contractors AB412412 2525 Pio Pico Drive•Suite 102•Carlsbad,CA 92008•Telephone(760)753-1453•Fax(760)635-0839 November 9, 2003 City of Encinitas Engineering Services 505 South Vulcan Avenue Encinitas, CA 92024 Project: Grading Permit Number 7533-G 1114 Double LL Ranch Road, Encinitas Lot 2, Map 13791, Encinitas — APN 264-241-15 Subject: Engineer's Pad Certification for Release of Building Permit Pursuant to section 23.24.3 10 of the Encinitas Municipal Code,this letter is hereby submitted as a Pad Certification Letter for 1114 Double LL Ranch Road, Encinitas. As the Engineer of Record for the subject project, I hereby state the rough grading for the new building pad was completed in conformance with the approved plans and requirements of the City of Encinitas' codes and standards. VII. The following provides the pad elevations as field verified and shown on the approved grading plan: Pad Elevation Pad Elevation Per Location Per Plan Field Verification Pad 229.5 229.5 VIII. Construction of line and grade for all engineered drainage devices and retaining walls have been field verified and are in substantial conformance with the subject grading plan. IX. The location and inclination of all manufactured slopes and walls have been field verified and are in substantial conformance with the subject grading plan. X. The construction of earthen berms and positive building pad drainage have been field verified and are in substantial conformance with the subject grading plan. The field verification of the pad elevations noted herein was provided by Steven Woods, L.S. 6427 of Woods Land Surveying,per his letter dated October 28, 2003, attached for reference. This pad certification letter is resubmitted for your records as a replacement to our certification letter dated October 30, 2003. That letter version noted an incorrect site address for the project site. Submitted by, Conway& Associates, Inc. QW0 f E S S 1 o* �p aE L X. p ! CIO ... Ha.41022 M Michael K. Pasko, P.E. EXPIRES 3-31-2007 a Engineer of Record lF �p CAt1E�� cc: Scott Nelson- owner \\fileserver\projects\02-001 nelson\wordproc\02-001_padcert.doc Conway & Associates, Inc. Civil Engineers/Surveyors/General-Ending Contractors AB412412 2525 Pio Pico Drive•Carlsbad,.CA 92008•Telephone(760)753-1453•Fax(760)635-0839 JUN HYDROLOGY CALCULATION - -� and HYDRAULIC ANALYSIS for NELSON RESIDENCE LOT 2 - MAP 13791 ENCINITAS, CA APN 264-241-15 GRADING PLAN nnnn-G F � D fvA ��pfESS/�♦ �V �E t K. p '�! m N�.41022 d EUMES 3-31-2003 � top lE 9p C Alt% Prepared: June 21, 2002 Conway & Associates, Inc. Civil Enginms/Surveyors/General-Engkwerbtg-HAZ Coutradom AB412412 2525 Pio Pico Drive•Carlsbad,CA 92008•Telephone(760)753-1453•Fax(760)635-0839 INDEX INDEX Page 2 INTRODUCTION AND REPORT METHODOLOGY Page 3 TIME OF CONCENTRATION CALCAUAATIONS & TRIBUTARY BASIN HYDROLOGY COMPUTATIONS Page 5 STORM DRAIN SYSTEM DESIGN CALCULATIONS Page 14 ONSITE HYDROLOGY MAP(1"=50', 11"x17") Page 21 Page 2 Conway & Associates, Inc. Civil Engnreers/Surveyors/General-Engineering-HAZ Contractors AB412412 2525 Pio Pico Drive•Carlsbad,CA 92008•Telephone(760)753-1453•Fax(760)635-0839 INTRODUCTION AND REPORT METHODOLOGY Introduction The purpose of this report is to present the results of the hydrology study and hydraulic design analysis prepared by Conway and Associates, Inc. for the proposed Nelson Residence project site. This report serves as the basis of design for the various on-site storm drain facilities shown on the project grading plans. The storm drain facilities analyzed in this report are based on a 100-year return rainfall event. Site Description The subject site is Lot 2 of Map 13791 (TM 97-219, Phase 1) in Encinitas, CA(APN 264-241-15). The subject site fronts on Double LL Ranch Road to the south. The subject site is an irregular quadrangle, encompassing 2.02 acres with large portions of the site consisting of relatively steep slopes. The proposed site development consists of a single family residence with slope grading and paved driveway. Reference the I"=50' scale hydrology map (11"x 17") located in this report for the site location and the relative limits of the offsite tributary basin. General Basin Descriptions and Flow Characteristics The topography in and around the project site slopes easterly and runs generally parallel with Double LL Ranch Road. An existing D-75 concrete-lined drainage ditch runs along the south toe of slope of the road embankment. This ditch was installed as part of the initial improvements for the Double LL Ranch subdivision and was designed to convey runoff from Lots 1, 2 and 3 of Map 13791 and Parcel 4 of Parcel Map 17446. Reference the hydrology report prepared by Conway& Associates, Inc. dated February 9, 1999 for TM 97-219, Phase 1 and Phase 2 on file with the City. The proposed house pad grading shown on the project grading plans will intercept the natural eastward runoff. This intercepted flow and the runoff from the graded pad and artificial slope areas of the site will be directed to the existing D-75 ditch by a series of ditches and culverts to be constructed as part of the proposed site grading work. The offsite tributary basins(Basin A and Basin B)lay westerly of the subject site and consists mainly of steep- sloped, naturally vegetated land fringed with rural-density development. The storm flow runoff from Basin A and Basin B is intercepted by a new top of slope drain swale that runs along the westerly and northerly pad limits. The outflow of the new top of slope drainage ditches discharge at the existing D-75 concrete ditch. Runoff from the southerly half of the west cut slope and pad area(Basin E) is collected by private storm drains that discharge into the existing D-75 ditch located along Double LL Ranch Road. Runoff from the driveway parking and roof areas of Basin E are directed to a catch basin insert-type storm water filter as part of the project's SUSMP water quality control elements. Runoff from the northerly half of the west cut slope and pad area(Basin C) is collected by private storm drains that discharge into the existing D-75 concrete ditch. Runoff from the cut slope, roof and lawn areas of Basin C are directed to long reaches (over 4001f) of grass-lined drain swales as part of the project's SUSMP water quality control elements. Page 3 Conway & Associates, Inc. Civil Engineets/Surveyors/Geneml-Engineering-HAZ Contractors AB412412 2525 Pio Pico Drive•Carlsbad,CA 92008•Telephone(760)753-1453•Fax(760)635-0839 Hydrology Study Methodology A rational-method format was used to evaluate runoff quantities for the tributary basins presented herein in accordance with the County of San Diego hydrology manual. This hydrology study uses runoff coefficients appropriate to soil type 'D': 0.45 for the rural-residential zoned areas with weighted averages used when the basin consisted of mixed surface types. Offsite Basin A Summary- (1.27 acres) Tributary to a Rock-Lined or Concrete-Lined Channel: A 100-year return rainfall event yields a time of concentration of 13 minutes for offsite Basin A, a 6-hour, 100-year frequency rainfall event of 2.7 inches, with a peak rainfall intensity of 3.8 inches/hour. A 100-year return design flow of 2.2 cfs was computed for the ditch design flow. The reserve capacity of the 1'-deep channel is approximately 2000/o of the design flow. Offsite Basin B and Onsite Basins C&D Summary- (0.85 acres) Tributary to a Rock-Lined or Concrete- Lined Channels and Grass-Lined Swales: A 100-year return rainfall event yields a time of concentration of 28 minutes for Offsite Basin B and Onsite Basins C & D, a 6-hour, 100-year frequency rainfall event of 2.8 inches, and a peak rainfall intensity of 2.3 inches/hour. A 100-year return design flow of 0.3 cfs was computed for the top of slope ditch design flow, 0.3 cfs for the pad-area grass-lined swale design flow, and 1.0 cfs for the rock and grass-lined swale design flow(along the easterly toe of the new fill slope). A storm water filter system manufactured by.Kristar Enterprises (`Flo-Gard' catch basin insert, Model FF- 24D)was specified for the mast-downstream catch basin of Basin C in compliance with SUSMP requirements. All storm water runoff from the paved areas of Basin C is directed through this proposed filter system. The proposed storm water filter has a net flow capacity of 133 GPM, in excess of the computed design peak outflow rate of 32 CFM. The runoff from the unpaved areas of Basin C not directed to the catch basin with the storm water filter will flow through the grass-lined swale located at the top of the fill slope on the East edge of the pad before it enters the storm drain system. New 12"oHDPE SD @ Driveway Entrance: The proposed driveway entrance culvert that will replace a portion of the existing D-75 ditch was sized based on deign flow computations contained in the February 1999 hydrology study for TM 97-219. A design flow of 9.0 cfs was used in the culvert analysis, the combined flows from sub-basins F.1 and G.1 as contained in that report. Conclusion It is the professional opinion of Conway and Associates, Inc. that the proposed storm drain systems shown on the project's grading plans will convey the Q100 design flows anticipated by the calculations contained in this report. Page 4 Conway & Associates, Inc. Civil Engineers/Serveyors/General-Engineering Contractors AB412412 2525 Pio Pico Drive•Carlsbad,CA 92008•Telephone(760)753-1453 a Fax(760)635-0839 TIME OF CONCENTRATION AND TRIBUTARY BASIN HYDROLOGY COMPUTATIONS Y2 x __...._,_T.__.._._.._.______._.__ l °'o��_x..____-�aTp__�.�o._�,�i�'^'_✓ �i'�e1(rv....._�,.__.�.___.G�...-._!.�_,_...�'._�.le _ G-%:_,fir / �__._.__....�_,..___ 1'7e) _�_ l Conway & Associates, Inc. Civil Engineaas/Surveyors/General-Engineering Contractors AB412412 i +v w Warr ww�.—.ss mss.. "— ea.r �sml6'rsr'mocrg sxm�.�rr®.se.r®twe�an.eeer �..eer.r rrer � Ie ae.ie!R ar rmeelr IE 8srie IIMS era w i Mao�ems® 2eeesR�eo rr+crr srsatR ades.�eec II� iRn P��'rta.e.araeus erl:ra s r ide s•r a®r s orr s rRIS'�.e pR.ir LrIRORi rriio�a� � �r/��l�Y�R l�lW€Yf 4 5!r�Y8-el rri r r r EeYii i� - r m�AeR Pil[iF4�fYa a�r�r �Y Yraer utr saw errors 6iilr 9e'!!�®Afs f•ra 1re�17f�iDQ� anwrrrrr s asa,r tawaw.reresa rwrwr�srarMIKK Eaeis.a® r�rr�aa�®a�v �i�ra�r r��r iraq, �araw®a:s�rrsraw®a�®rE y l IPA rPAMAllill'L jtrA-f "Ifft toEweti! M;Kjmn fin LI"!'' ���r�1tB1fD A C'fn WrUl/LHY11 i9tl rf iM It IN E M i M tilEUISSNIVA AME �� �lMil',S iEL8rShclM11111111111 01•i ffl61iEA43lll(C�ifti#E�ftf!!f!fE#fFI�I / �i�.lff�tie�Ll�ffl�Elfi4fflN/llilfsiw■■ wl yea..earwA..r...+.®.M....®..e za5.r.ca..s.oaFeMM..>mer_rw�®. ar ear ,elrsso.••rr�r�.ISm..v�tw..s....R.R.rzse=.ww eta s.acs.w.®..ease rise !-srW WMW W parr' dW �elMMVAloe ew rws®1'.rKE[Gfrtf eeR r-5cBs.ra:gerrwuRR1• reR7Y/dII rOF.�P Ja rag rs!'�f MI�Aeas9l.e®re11111iP � _ asa�eer»cau�xirlcis:ialrrsuR w/a� �r.rr41sM�le.�eW psi la �'9lrlrpf 6' aR�e a�miaar��ao U#q.°A 1®�i®ee MiW°Jia cease � rer a.lvc��a,e.ee�euc�rr1eR:a IsR MlRaa renrraas YI _ Rte'�W eS" .MMW B»a+'rt�R�l' i a�t�la®�Alai R1siK C.@'a 6A1�GJp i-1@idiR RIBM a!G®®r.q ' AgowIa'kY Anww i4s.l�� �Naa�llf Raelvda LSM&Mk iRF IRer f3M8Mmm lYQ� IafR ea/AJ MIK�l(�LN'�LCSZ'Ilii�°raffia ��OS®l�ii�®[ai16A f64'YK1N Ri R i i ERR R10mMM IV=w �',� rYl�r'l®7i mmr 2w7 =nm fm _ �77 RJR 1,fs�Cll� ��'e�ISie�91=I, iil�4 ilr����BTBgi!E�s�e WTX=Sx V1Me VLM: aisssr Jair L; rAQ iF! 1R8tTlrl/II ==MKWW�if�AliiiM i^��BiiHgAiRR1■r=�lslali ]t6" I d �{l�ly 7s>!6 lI NINA 7OOi 1ll�tRR[�f�lf�iii3M[tRt�iA[ l�iAT.'i!'"/I AWAKYAKW*WWA. ►.�Or/ i� �ll Elii�L3' l[�!1[>��1.� FAF 1#�JC*'AIWWAIF AiWfi MAW A fffff� iii uuimumlInglist,S isli;iiii" rAi � � A IKA g F[ III lil 1� I tn...t ca L r Go CD CC N ca LAW O vM �►L3 =. i MY- C2 }, t Va vat: � � .; ;�• rr: �f ,�: . it •` C z e o �i X t — U t ul � W 1 �O ^- G � a �y s ti s � 0 UA vi OW Ic OW � uj z ° 0 M .1 < u w L h Conway & Associates, Inc. Civil Engineers/Surveyors/General-Engineering Contractors AB412412 _� .� • i I F ni Zj LL Lr Cb Oi .... O ft M N1 +a a tr ✓ •el'` i _ i LAJ �`..� � - Uj Uj A Cn EXI C* mtpw 1 ! ~ Up ce w F M C r` x Q 1 CS 14 CD COD 1 U.A u rr tr... Lf O a r1 r! r `Z CV21 w x it- 02 0 '�T Ys) t- ih Z L) fQ1 k. ~1 cc _ a W �c NaC M Q =a < OwJ� �w g.2 1d6 < p M M F, u re a Y Conway & Associates, Inc. Civil Engineers/Surveyors/General-Engineering Contractors AB412412 rn EFFECTIVE SLOPE COMPUTATION FOR NATURAL WATERSHED PER CoSD APPENDIX X—B co FX4 325 kn co HI PT Oq- TRIG LITARY '' 325 --- -BASINIEL 327_.Uf 300 00 w Z) �j ----- s4iept T rv.A3 = 966 SF cn w t 275 00 wwN C14 ADE_.J IL.OWNG TRIG L I TARY 'BASIN 250 Al = 350 23 225 Al +A2 868 5F Q) 200 1 Z 0 c� Cl cn C) + + + Lu Z cd STATIONING ALONG WATERSHED 0 0 PREPARED 6/12/02 2 x � \ m 2 7 0 2 .\ S \ ƒ d m \ / + , § 0) E E_ E - � \ CIO. / / O q } � 06 co\ a co ca UJ LU k k « $ C4 Y 2 Ix 2 E � S � � W & Q 0 O LU cn r- 00 co r-- $ @c C � & & � o / ¥ C « U 2 } ® z z CL § CO � � ) � Z o CO LLj / / D m 2 R e § w 2 z 0w _ rA W � 2 � c 2 � 3 00 \ q0 0 � � o � � � 3zE z >- z W - _ « gym - w � � � � � � � TZ Q2Ow3 # k 2 o f 7 E f O � o w n B / q ° � = S 0 aac0 ¥ / zm k 2 � // N X 00 O M 0 k' L M � M L h () O C.7 O p C c- o p a d H Cc CS Cc Cc cc U '[f cl Q a CL Q V U U co U U co Z C c C C C U > 0 Q C a cc OL cc cc cc F— cc is C W CC Lac W P. W cc n, n CL m ID cc cc cc 2 2 Ll Y (n cc cc � N cc � cc cc 3 w cc v -c c c � c c O V m m 0 m ccc cc m cccc c cc cu OJ J J J J J J O J J W LL w O LO C9 CO CD z v � a ? W `_` � � U 0 m W m O O ° ° O cn LO ° Ln o LO ° LC) LO F- Co M Co Co Lo T v co ° sfi 1- M LC) o (n a M LO N O N N LS') Ln .- * 'W LD N CC) T T Cn C> M V t0 N T M LQ LC) CO CC) N r LO Co O M T co Lc U Cl) N M cr N r N 1-: r r N � T LO LO LA LO LO IX) LO Ln W) LO Ul) O tri M CA LO LC) M LO M O M M w - O O O O O O O O O O O U UU oLL Y+1 O CD M CO �D O M � O r d' LO M M r �- Ln O LC) M T CO O M 0 M LO 1� r r" 1l 1- O N r Ic CO CD 1- M O N O W C < Q Q, O ►n O M T U') CO) co T I� M 00 •,i N W � a � T W 0 „fit (n Z f V vii W Cry :D r' N M T N r N M ql� Ln Z0 U) < U U U U D W W W W W C C', 00 0 u Z 2 m d % CINI \ / $ 3 \ m k k CO \ S � k \ 7V- 0) $ 0 § § co � 3 \ BOO / . / 2 m m m / b b h . LO q 0 $ u , a & & o 6 0 - 0 0 \ AC) m u } 2 0 LL / / W \ m w / k U) 0 ( / > O S 3: � y n n � Cl) CYd R _ &' & & &0 Z 2 § : ui o / R z I 0 k k E k q \ 0 0 6 0 0 U) � . 6 \ w ) ± CV q k q \ . 2 § > w - 0 0 0 0 & t $ h ) � < / Z \ & k k < � � k � � � ca ice . k ƒ \ 2 q a_ < \ k / � E2 q E § n y z � § w0 ■ k 2 - m m $ f R � \ _ � ac � � j k ¢ 7 �� /� Conway & Associates, Inc. Civil Engineers/Surveyors/General-Engineering Contractors AB412412 2525 Pio Pico Drive•Carlsbad,CA 92008•Telephone(760)753-1453•Fax(760)635-0839 STORM DRAIN SYSTEM DESIGN CALCULATIONS i D-75 INTERCEPTING DITCH @ TOP OF SLOPE ii ROCK-LINED INTERCEPTING DITCH * TOP OF SLOPE iii ON-SITE STORM DRAIN- 12" SD (a� DRIVEWAY ENTRANCE iv ON-SITE STORM DRAIN - ONSITE 6" SD V GRASS-LINED CHANNEL vi ROCK-LINED BERM �a, EASTERLY PROPERTY LINE / 4- 02-001 Nelson: Basin A D-75 Worksheet for Circular Channel Project Description Project File p:102-001 nelsonihydro101002-a.fm2 Worksheet Basin A D-75 Flow Element Circular Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.016 Channel Slope 0.010000 fvft Diameter 24.00 in Discharge 2.20 cfs Results Depth 0.47 ft Flow Area 0.56 ft2 Wetted Perimeter 2.02 ft Top Width 1.69 ft Critical Depth 0.52 ft Percent Full 23.36 Critical Slope 0.006776 fVft Velocity 3.94 ft/s Velocity Head 0.24 ft Specific Energy 0.71 ft Froude Number 1.21 Maximum Discharge 19.77 cfs Full Flow Capacity 18.38 cfs Full Flow Slope 0.000143 fUft Flow is supercritical. 06/20/02 Conway&Assoc.Inc FlowMaster v5.07 02:17:08 AM Haestad Methods,Inc. 37 Brookside Road Waterbury,CT 06708 (203)756-1666 Page 1 of 1 A5 02-001 Nelson: Basin A Trap Ditch Worksheet for Trapezoidal Channel Project Description Project File p:\02-001 nelson\hydro\01002-a.fm2 Worksheet Basin A Trap Ditch Flow Element Trapezoidal Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.045 Channel Slope 0.010000 ft/ft Left Side Slope 2.000000 H :V Right Side Slope 2.000000 H :V Bottom Width 1.00 ft Discharge 2.20 cfs Results Depth 0.60 ft Flow Area 1.32 ft2 Wetted Perimeter 3.68 ft Top Width 3.40 ft Critical Depth 0.41 ft Critical Slope 0.049559 fttft Velocity 1.67 ftts Velocity Head 0.04 ft Specific Energy 0.64 ft Froude Number 0.47 Flow is subcritical. 06/20/02 Conway&Assoc.Inc FlowMaster v5.07 02:17:16 AM Haestad Methods,Inc. 37 Brookside Road Waterbury,CT 06708 (203)755-1666 Page 1 of 1 02-001 Nelson: Driveway Culvert Worksheet for Circular Channel Project Description Project File pA02-001 nelson\hydro\01002-a.fm2 Worksheet Driveway Culvert Flow Element Circular Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.009 Channel Slope 0.100000 ft/ft Diameter 12.00 in Discharge 9.00 cfs Results Depth 0.53 ft Flow Area 0.42 ft2 Wetted Perimeter 1.63 ft Top Width 1.00 ft Critical Depth 0.99 ft Percent Full 53.10 Critical Slope 0.028254 ft/ft Velocity 21.24 ft/s Velocity Head 7.01 ft Specific Energy 7.54 ft Froude Number 5.75 Maximum Discharge 17.51 cfs Full Flow Capacity 16.27 cfs Full Flow Slope 0.030588 ft/ft Flow is supercritical. 06/20102 Conway&Assoc.Inc FlowMaster v5.07 02:14:09 AM Haestad Methods,Inc. 37 Brookside Road Waterbury,CT 06708 (203)756-1666 Page 1 of 1 / 7 02-001 Nelson: Basin E Site SD Worksheet for Circular Channel Project Description Project File pA02-001 nelsonftdro101002-a.fm2 Worksheet Basin E: Site SD Lines Flow Element Circular Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.009 Channel Slope 0.010000 fyft Diameter 6.00 in Discharge 0.70 cfs Results Depth 0.36 ft Flow Area 0.15 ft2 Wetted Perimeter 1.01 ft Top Width 0.45 ft Critical Depth 0.42 ft Percent Full 71.72 Critical Slope 0.007102 ft/ft Velocity 4.64 ft/s Velocity Head 0.34 ft Specific Energy 0.69 ft Froude Number 1.42 Maximum Discharge 0.87 cfs Full Flow Capacity 0.81 cfs Full Flow Slope 0.007460 ft/ft Flow is supercritical. 06/20102 Conway&Assoc.Inc FlowMaster v5.07 02:16:55 AM Haestad Methods,Inc. 37 Brookside Road Waterbury,CT 06708 (203)755-1666 Page 1 of 1 02-001 Nelson: Basin C Lawn Swale Worksheet for Triangular Channel Project Description Project File pA02-001 nelsonlhydro101002-a.fm2 Worksheet Basin C Lawn Swale Flow Element Triangular Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.035 Channel Slope 0.020000 ft/ft Left Side Slope 5.000000 H :V Right Side Slope 5.000000 H :V Discharge 0.20 cfs Results Depth 0.18 ft Flow Area 0.17 fly Wetted Perimeter 1.86 ft Top Width 1.82 ft Critical Depth 0.16 ft Critical Slope 0.042668 ft/ft Velocity 1.20 ft/s Velocity Head 0.02 ft Specific Energy 0.20 ft Froude Number 0.70 Flow is subcritical. 06/20102 Conway&Assoc.Inc FlowMaster v5.07 02:17:23 AM Haestad Methods,Inc. 37 Brookside Road Waterbury,CT 06706 (203)755-1666 Page 1 of 1 !9 02-001 Nelson: Basin D PL Ditch Worksheet for Triangular Channel Project Description Project File pA02-001 nelson\hydro\01002-a.fm2 Worksheet Basin D PL Ditch Flow Element Triangular Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.045 Channel Slope 0.010000 ft/ft Left Side Slope 2.000000 H :V Right Side Slope 10.000000 H :V Discharge 2.70 cfs Results Depth 0.57 ft Flow Area 1.93 ftz Wetted Perimeter 6.96 ft Top Width 6.80 ft Critical Depth 0.42 ft Critical Slope 0.051359 fUft Velocity 1.40 fus Velocity Head 0.03 ft Specific Energy 0.60 ft Froude Number 0.46 Flow is subcritical. 06/20/02 Conway&Assoc.Inc FlowMaster v5.07 02:17:30 AM Haestad Methods,Inc. 37 Brookside Road Waterbury,CT 06708 (203)755-1666 Page 1 of 1 ZIP Conway & Associates, Inc. Civil Engineers/5urveyors/General-Engineering Contractors AB412412 2525 Pio Pico Drive•Carlsbad,CA 92008•Telephone(760)753-1453•Fax(760)635-0839 HYDROLOGY MAP (1"=50', 119'x17") zi N • !5 otl v k� t A VVk , OfSIGNATOR SCALE. 10 ,� V4 77 N4SQk flksfO CEi OGY /6 7E IJ 41b umit'. rL % P1 A ok V 'IN a Ir I Af jr I A Ali N 1A dip 41 _lj oil I N, tj EA, E.3 LZ an ------- --------- so —4 nn �s 4AT I It -- ---- nn. n-7. An Nlnlcr%rl\ rofc\nqQC)j vAQ Amn - ----- COAST GEOTECHNICAL CONSUIXING ENGINEERS AND GEOLOGIST'S - December 2, 2003 K. Scott Nelson 5902 E. Miramar Drive Tucson, AZ 85715 Subject: ROUGH GRADING REPORT Grading Permit 7533-G Proposed Single Family Residence Lot 2, 1114 Double LL Ranch Road Map No. 13791 APN 264-241-15 Encinitas, California Reference: PRELIMINARY GEOTECHNICAL INVESTIGATION Proposed Single Family Residence Lot 2, Double LL Ranch Encinitas, California Prepared by Coast Geotechnical Dated March 8, 2002 Dear Mr. Nelson: ® In response to your request, we have performed field observations and testing during the rough grading phase on the above referenced property. The results of our density tests and laboratory testing are presented in this report. Based on the results of our testing, it is our opinion that the fill was placed in an adequate manner and compacted to a minimum of 90 percent of the laboratory maximum dry density. However, the fill deposits are expansive. _ If you have any questions, please do not hesitate to contact us at (858) 755-8622. This opportunity to be of service is greatly appreciated. Respectfully submitted, COAST GEOTECHNICAL Mark Burwell, C.E.G. Vithaya Smghanet, P.E. Engineering Geologist Geotechnical Engineer 779 ACADEMY DRIVE SOI ANA BEACH, CALIFORNIA 92075 (858) 755-8622 • FAX (858) 755-9126 i ROUGH GRADING REPORT Proposed Single Family Residence Lot 2, Double LL Ranch Encinitas, California Prepared for: K. Scott Nelson 5902 E. Miramar Drive Tucson, AZ 85715 December 2, 2003 W.O. G-347012 -- Prepared by: COAST GEOTECHNICAL 779 Academy Drive Solana Beach, California 92075 Coast Geotechnical December 2, 2003 W.O. G-347012 Page 3 INTRODUCTION This report presents the results of our observations and field density testing on the subject property. u The project included the cutting and filling of an easterly sloping lot, in order to develop a level building pad. The results of our density tests are presented on Table I. The approximate locations of these tests are shown on the enclosed Grading Plan, prepared by Conway and Associates. LABORATORY TEST DATA The laboratory standard for determining the maximum dry density was performed in accordance with ASTM D 1557-91. Field density tests were performed in accordance with ASTM D 1556. The ._ results of the laboratory maximum dry density, for the soil types used as compacted fill on the site, is summarized below: Maximum Dry Density Optimum Soil Type Description .c.f. Moisture %) A Mixture of on-site 116.7 soils, tan to brown 15.2 silty, slightly sandy clay GEOTECHNICAL CONDITIONS The subject property is underlain by greenish, tan to brown sandy claystone and clayey sandstone which appears lithologically equivalent to rock units of the Del Mar Formation. The clayey sedimentary rock units are subject to downslope creep along highly fractured and weathered zones. The sedimentary rock units are overlain by clayey soil deposits. Coast Geotechnical December 2, 2003 W.O. G-347012 Page 4 EXPANSIVE SOILS - Testing suggests that the upper pad soils have a potential expansion in the upper extent of the medium range. DISCUSSION The grading contractor on this project was Pacific Coast Grading. The following is a discussion of the general grading operations, as they were performed on the site. _ 1) All surface deleterious material was removed from the area of proposed grading. 2) A minimum 15 foot wide key was excavated along the base of the proposed fill slope. The ._ key extended through weathered claystone of the Del Mar Formation. A subdrain consisting of a 4.0 inch diameter pipe, embedded in gravel and wrapped in filter fabric was installed along the back of the key. 3) Prior to placement of fill, the base of the key excavation was scarified, moistened and compacted. 4) Fill consisting of a mixture of on-site excavated materials was placed in loose lifts of about 8.0 inches thick. The fill was moistened as required to optimum moisture content or above Coast Geotechnical December 2, 2003 W.O. G-347012 Page 5 and compacted. Compaction was accomplished by track rolling with heavy earth moving - equipment and by a motorized vibratory sheepsfoot. Fill was benched into the underlying clayey rock units. 5) As recommended in the referenced Preliminary Geotechnical Report, the rear cut slope was constructed as a stabilization fill. A minimum 20 foot wide key was excavated along the base of the slope extending a minimum of 2.0 feet into sedimentary rock. A 4.0 inch diameter subdrain was constructed along the back of the key. Fill was placed as previously indicated and benched into the sedimentary rock units. The stabilization fill is composed of on-site materials, mixed and placed as compacted fill. 6) Fill slopes were overbuilt and trimmed back to a maximum gradient of 2:1 (horizontal to vertical). 7) The cut/fill transition along the building pad was undercut approximately 3.0 feet and replaced with compacted fill as recommended in the referenced report. The undercut, in general, extends a minimum of 5.0 feet beyond the building footprint. 8) The depth of fill ranges from 3.0 feet in the rear of the building pad to approximately 8.0 feet in the lower keyway. Coast Geotechnical December 2, 2003 W.O. G-347012 Page 6 9) A trash fill was encountered in the proposed driveway area along the southern portion of the pad. The 40 foot by 30 foot area contained tires, steel, plastic and wood. No apparent hazardous materials were observed. The debris was removed from the site and the excavation was backfilled with on-site materials. 10) Based on selective testing, the fill was placed to a minimum of 90 percent of the laboratory maximum dry density, as suggested by our test results. CONCLUSIONS AND RECOMMENDATIONS General Highly expansive clays were generally used in the lower portion of the key area for the fill slope. Slightly sandier deposits were used in the building pad. This approach reduced the expansion potential of the upper pad soils, to some degree. Testing suggests that the expansion potential of the pad soils is in the upper extent of the medium range. Although the pad soils are slightly less -- expansive, a post-tensioned slab is still recommended and should be considered for the project. However, conventional foundation design parameters are presented below. These recommendations have been revised from our Preliminary Geotechnical report. All footing and slab areas should be pre- "- moistened three to five days, prior to pouring concrete. Additional recommendations for pre- _ saturation will be provided at the time of foundation excavation. Coast Geotechnical December 2, 2003 W.O. G-347012 Page 7 Foundations Conventional (Revised) Although some degree of variation occurs, testing suggests that the fill deposits in the building pad _- exhibit a potential expansion in the medium-range. Therefore, footings may be redesigned based on the following soil parameters. Footings should be founded a minimum of 24 inches below the lower most adjacent grade at the time of foundation excavation, for single and two story structures. A 12 inch by 12 inch grade beam should be placed across the garage opening. Footings should be reinforced with a minimum of four No. 5 bars, two along the top of the footing and two along the base. The base of footings should be maintained a minimum of 10 lateral feet from the face of the nearest slope. Footing recommendations provided herein are based upon underlying soil conditions and are not intended to be in lieu of the project structural engineer's design. -- Slabs on Grade (Interior and Exterior) Previous slab on grade recommendations remain applicable. However,recommended non-expansive compacted fill underlying proposed interior slabs may be reduced to a thickness of 8.0 inches. Fill Slopes Locally derived clayey soils used as compacted fill are expansive. Our experience suggests that compacted fill slopes may experience varying degrees of slope yielding due to moisture fluctuations and related expansion/contraction of the clayey deposits. The slow lateral downslope movement can adversely affect footings, concrete flatwork and pavement sections adjacent to the fill slopes. Additional recommendations may be necessary, in this regard, depending upon final design plans. Coast Geotechnical December 2, 2003 W.O. G-347012 Page 8 Proposed Driveway - The recommended driveway section in the Preliminary Geotechnical study remains applicable. Drainage Specific drainage patterns have been designed by the project civil engineer. However, in general,pad water should be directed away from foundations. Roof water should be collected and conducted to area drains, via non-erodible devices. Pad water should not be allowed to pond or flow onto slopes in an uncontrolled manner. Vegetation adjacent to foundations should be avoided. If vegetation in these areas is desired, sealed planter boxes should be considered. Other alternatives may be available, however,the intent is to reduce moisture from migrating into foundation subsoils and under concrete flatwork. Slopes should be planted with drought resistant vegetation. Irrigation should be limited to that amount necessary to sustain plant life. The interceptor drain along the top of the stabilization fill should be maintained and cleaned on a periodic basis. All drainage facilities should be inspected and cleaned on an annual basis, prior to winter rains. Observations and Density Testing Structural footing excavations should be observed by a representative of this firm, prior to the placement of steel. Additional fill should be placed while a representative of this firm is present to observe and test. Coast Geotechnical December 2, 2003 W.O. G-347012 Page 9 Plan -- A copy of the final plans should be submitted to this office for review, prior to the initiation of construction. Recommendations provided in the referenced report which are not superseded by this report remain applicable and should be implemented in the design and construction phases. LIMITATIONS This office assumes no responsibility for any alterations made without our knowledge and written approval to the slope or pad grade on the subject lot, subsequent to the issuance of this report. All ramps made though slopes and pads, and other areas of disturbance which require the placement of compacted fill to restore them to the original condition, will not be reviewed unless such backfilling operations are performed under our observation and tested for required compaction. Observations and density testing were performed on a minimal periodic basis only. Complete observation and testing during the grading phase was not desired by the owner. Further, the site is underlain by expansive soils. Some degree of cracking and movement of structures constructed on these soils '— should be anticipated. This study has been provided solely for the benefit of the client and is in no way intended to benefit or extend any right or interest to any third party. This study is not to be used on other projects or extensions to this project except by agreement in writing with Coast Geotechnical. Enclosures: Field and Laboratory Test Results Grading Plan FIELD AND LABORATORY TEST RESULTS TABLE I Field Dry Density and Moisture Content (Swimming Pool Backfill) Moisture Dry Relative Test Test Approx. Content Density % Soil Date No. Location Elev. ° cf Compaction Type _ 5/01/03 1 See Map 214 ' 18 . 6 108 . 8 92 A 5/01/03 2 See Map 214 ' 20 . 1 110 . 9 95 A 5/02/03 3 See Map 218 ' 17 . 6 112 . 8 97 A 5/05/03 4 See Map 217 ' 19 . 8 _ 107 . 1 92 A 5/06/03 5 See Map 216 ' 18 . 7 109 . 2 94 A _ 5/07/03 6 See Map 217 ' 20 . 1 107 . 4 92 A 5/28/03 7 See Map 219 ' 16 . 7 108 . 5 93 A 5/28/03 8 See Map 219 ' 17 . 5 105 . 7 91 A 5/28/03 9 See Map 222 ' 16 . 3 - 107 . 2 92 A 5/29/03 10 See Map 225 ' 16 . 9 108 . 6 93 A 5/29/03 11 See Map 225 ' 17 . 6 107 . 1 92 A 5/29/03 12 See Map 227 ' 18 . 2 108 . 7 93 A 6/06/03 13 See Map 222 ' 18 . 8 106 . 9 92 A 6/06/03 14 See Map 223 ' 17 . 3 - 109 . 1 94 A 6/06/03 15 See Map 227 ' 19 . 6 104 . 9 90 A 7/07/03 16 See Map 230 ' 20 . 1 110 . 1 94 A 7/09/03 17 See Map 232 ' 18 . 6 107 . 9 92 A 7/14/03 18 See Map 234 ' 18 . 2 108 . 7 93 A 7/14/03 19 See Map 233 ' 15 . 6 - 112 .4 96 A (Page 1 of 2) TABLE I (Continued) Field Dry Density and Moisture Content (Swimming Pool Backfill) Moisture Dry Relative Test Test Approx. Content Density Soil Date No. Location Elev. ° cf _Compaction Type 9/08/03 20 See Map 220 ' 17 . 0 110 . 6 95 A 9/09/03 21 See Map 222 ' 18 . 4 110 . 5 95 A 9/09/03 22 See Map 229 ' 16 . 1 108 . 0 93 A 9/09/03 23 See Map 229 ' 15 . 2 107 . 2 91 A 9/09/03 24 See Map 226 ' 16 . 9 108 . 1 93 A TABLE II Expansion Index Test Results (U.B . C. Standard 18 . 2) Sample Location _Expansion Index Pad 83 (Medium) G-347012 (Page 2 of 2) h0 C WZ h N �O� m I S US 6�g H P Oi t7l < �e J a� W a VF j boj C7 C7 < N m ;T 2N ga as mad `" 1S+ ay� nU W ��� < \ v 122 Na �� Wp�� bi W< 8 m z- ff y < h �Ng Am C6 pp W� pyF yZ,...'� N ° J U -,.V(~j> IC� .,,W �l l� JI•.. �/Im=O `, d 9z OO N� 6� Z S iH Z 5,._ ► a U W S 1ly F r, �I a ►�/ WW "� .. U ;.,cm .p;FW\ N.S �N�' 2S F'< F MCI 'K� VFW ; pa a8'Z6 a law ;o OZ o. ` O •` 1.}y�Y h�j Z�, �.., O Z ~ Nlg�. \ 2 rye +. W�� 2 $ 8.- - Z-.., 2 a 2�, / ) O rA X �yS2. O;y0 �,' 2W ° X So qc ',,`O AIL a F W `//1/ go `G�< ���� ��ct' giin6 ya �. �� � :°<x ��O25 �D(�\':.:�� •.ai���� n w `O a � r�� �. �/ 0�...^ (V y ♦ h m\ n O. w p \ \ h ^ h '�. r '� h '.h h • � \.lid"\I � 1 / y r f0-7 'I \ I cN cc o o a yq� Qy t� cc O e c; 04, 7WFy _ O N !L /(-�� ggqoo'boa�o GbOOKpOOggqq � �\� j2 < W W<pWWb3h `r$ z Q / / r ❑ rj Q p vy~� �n \ b LS wg� �y fan � C 2 Q vGia u NI.i]+ ZS d1, W W9 � Slook-,, 0 p d /.r / 4 14 M 14 < %� )4: N ar O A10 W / t 4 00 W 4 Q 8 0 W OZC b ®---� / J � ; ai 6 4 Q lair 0i N id cc y�a��2. .� 4• ,/ Sgt i ,•d�, -,�. / � � ! ca5. 4 Z ^i 45 �FN2 S� � 8 b� p 3 • _]bp p.0® 4© x o i 4U� D �KW COQ Kid I N�cco n 4 . f. °j.'U 4 1 VCR iyYa h8 I / "' SrY �' O 4 b � ^ 4 - –— ^ \ I , - r= > P.. ---- -- i/1 \ l 9 COAST GEOTECHNICAL CONSULTING ENGINEERS AND GEOLOGISTS March 8, 2002 ® 15 K. Scott Nelson L!' h'}AR 1 3 L:G013 5902 E. Miramar Drive Tucson, AZ 85715 ENGINEERING SERVICES CITY Of ENCINITAS Subject: PRELIMINARY GEOTECHNICAL INVESTIGATION Proposed Single Family Residence Lot 2, Double LL Ranch Encinitas, California Dear Mr. Nelson: In response to your request and in accordance with our Proposal/Agreement dated May 30, 2001, we have performed a preliminary soils engineering investigation on the subject site for the proposed single-family residence. The findings of the investigation, laboratory test results and recommendations for foundation design are presented in this report. From a geotechnical point of view, it is our opinion that the site is suitable for the proposed development, provided the recommendations in this report are implemented during the design and construction phases. However, expansive soils, highly weathered formational rock and potential creep zones are present on the site and will require i special consideration during the design and construction phases. If you have any questions, please do not hesitate to contact us at (858) 755-8622. This opportunity to be of ee..is appreciated. Respectfully submit COAST GEOTECH 2109 �. 782 �xP. - 1 tam Exp.12-31-05 ENGINEE:RI17,4C Mark Burwell, C.E.G. Vitha a Sin hanet P.E. '9�' ECN�Xq Engineering GeologistV Geotechnical Engineer OF CPA, 779 ACADEMY DRIVE • SOLANA BEACH, CALIFORNIA 92075 (858) 755-8622 • FAX (858) 755-9126 PRELIMINARY GEOTECHNICAL INVESTIGATION Proposed Single-Family Residence Lot 2, Double LL Ranch Olivenhain, California Prepared For: K. Scott Nelson 5902 E. Miramar Drive Tucson, AZ 85715 March 8, 2002 W.O. P-347012 Prepared By: COAST GEOTECHNICAL 779 Academy Drive Solana Beach, California 92075 DUSTYL TR Y-L ----------- —�T N33-07083" ............. COPP ST HOLLOW RD 3:06667° 1 ----------- SUBJECT PROPERTY NI, yy --------- - ------'-----------200..._...... to­. 0 Foliw Naas r i 7`J -am ..................... N% rn .................... _5DEL RANCHO Copyright M 2000 n-L­­TopoToole Advanced Print ICIt rE. 8-1—1 9,600 Zoom L-1:I., V.t-_WC;S" 800 ft Coast Geotechnical March 8, 2002 W.O. P-347012 Page 5 INTRODUCTION This report presents the results of our geotechnical investigation on the subject property. The purpose of this study is to evaluate the nature and characteristics of the formational rock units underlying the property, the engineering properties of the surficial deposits and their influence on the construction of a single-family residence. SITE CONDITIONS The overall Double LL Ranch Estates includes 120+ acres of terrain located along the west side of Lone Jack Road, in the city of Encinitas. The eastern portion of the property is composed of gently sloping terrain and is incised by a south-trending stream. The western portion of the property is characterized by gentle to moderately steep slopes, ranging in gradients from 5:1 to 3:1 (horizontal to vertical) which ascend to a terrace plateau. The subject property (Lot 3) is part of a previous project dividing approximately 41.29 acres into twelve (12) separate lots. Lot 3 is bounded along the south by Double LL Ranch Road and to the west by an undeveloped lot. A recently constructed residence is present on the adjacent lot to the east. Relief on the site is approximately 45 vertical feet. Vegetation along the slopes includes a moderate growth of brush and shrubs. Drainage is generally by sheet flow to the east. A gunite drainage ditch is located parallel to Double LL Ranch Road. Coast Geotechnical March 8, 2002 W.O. P-347012 Page 6 PROPOSED DEVELOPMENT Preliminary grading plans were prepared by Conway and Associates. The project includes a cut/fill transitional building pad in the central portion of the lot. A 2:1 (horizontal to vertical) cut slope, up to 25.5 feet high, is planned along the western portion of the lot. A 2:1 (horizontal to vertical) fill slope, up to 8.5 feet, is planned along the eastern portion of the pad. Drainage will be directed to the driveway and a proposed grass lined swale along the eastern property line. The swale will connect to the existing gunite drainage ditch along Double LL Ranch Road. SITE INVESTIGATION Three exploratory trenches were excavated on the site with a tractor-mounted backhoe to a maximum depth of 15.5 feet. Earth materials encountered were visually classified and logged by our engineering geologist. Undisturbed, representative samples of earth materials were obtained at selected intervals. Samples were obtained by driving a thin walled steel sampler into the desired strata. The samples are retained in brass rings of 2.5 inches outside diameter and 1.0 inches in height. The central portion of the sample is retained in close fitting, waterproof containers and transported to our laboratory for testing and analysis. LABORATORY TESTING Classification The field classification was verified through laboratory examination, in accordance with Coast Geotechnical March 8, 2002 W-O. P-347012 Page 7 the Unified Soil Classification System. The final classification is shown on the enclosed Exploratory Logs. Moisture/Density The field moisture content and dry unit weight were determined for each of the undisturbed soil samples. This information is useful in providing a gross picture of the soil consistency or variation among exploratory excavations. The dry unit weight was determined in pounds per cubic foot. The field moisture content was determined as a percentage of the dry unit weight. Both are shown on the enclosed Laboratory Tests Results and Exploratory Logs. Maximum Dry Density/Optimum Moisture Content The maximum dry density and optimum moisture content were determined for selected samples of earth materials taken from the site. The laboratory standard tests were in accordance with ASTM D-1557-91. The results of the tests are presented in the enclosed -- Laboratory Test Results. Expansion Index Tests Expansion Tests were performed on selected samples. Test procedures were conducted in accordance with the Uniform Building Code, Standard No. 29-2. The classification of expansive soil, based on the expansion index, are as indicated in Table 29-C of the Coast Geotechnical March 8, 2002 W.O. P-347012 Page 8 Uniform Building Code. The test results are shown on the enclosed Laboratory Test Results. Shear Tests Shear tests were performed in a strain-control type direct shear machine. The rate of deformation was approximately 0.025 inches per minute. Each sample was sheared under varying confining loads in order to determine the Coulomb shear strength parameters, cohesion and angle of internal friction. Samples were tested in a saturated condition. The results of the tests are presented in the enclosed Laboratory Test Results. GEOTECHNICAL CONDITIONS Regional Conditions Hillside areas on the subject tract are underlain by two major sedimentary formational rock units. Most of the site above an elevation of 297 feet is underlain by tan to brown sandstone with interbeds or lenses of siltstone. These sedimentary units appear to correlate with Eocene age Torrey Sandstone. The sandstone is underlain by pale green siltstone/claystone units which appear to be lithologically equivalent to the Eocene age Del Mar formation. The clayey rock units are highly fractured, expansive and frequently associated with slope instability. These sedimentary units form thick clayey soil deposits which blanket the slopes. Coast Geotechnical March 8, 2002 W.O. P-347012 Page 9 The lower elevations of the tract are underlain by alluvial/colluvial deposits (undifferentiated). These deposits are typically composed of dark brown sandy clay and more recent sand, silt and clay with rock fragments within the present and former stream courses. Metavolcanic rock is present beneath the alluvial deposits along the stream course and most eastern margin of the property. These massive, well-indurated bedrock units have commonly been designated as the Santiago Peak Volcanics on published geologic maps. Site Specific Conditions A brief description of the earth materials encountered during site specific exploration is discussed below. Soil s Approximately 3.0 feet of soil was encountered in the exploratory trenches. The soil is composed of brown sandy clay. The soil is blocky in the upper 1.0 foot and generally soft and damp below. The contact with the underlying Del Mar formation is gradational. Del Mar Formation (Td) Underlying the soil, whitish tan to pale green sandy claystone was encountered. The exploratory trenches suggest the upper 3.0 feet of the clayey rock unit is highly weathered n Coast Geotechnical March 8, 2002 W.O. P-347012 Page 10 and soft. Below the weathered zone, the claystone is highly fractured. With depth, the claystone generally becomes less fractured and more competent. Bedding is poorly developed in the clayey rock units, however, previous studies suggest the sedimentary unit is relatively flat-lying with perhaps an out of slope dip of 1.0 degree. Expansive Soil Based on our experience in the area and laboratory testing of selected samples, the siltstone/claystone rock and clayey soil deposits have a potential expansion in the high range. Ground Water No ground water was observed in the exploratory trenches to the depth explored. However, previous studies suggest that seepage along fractures within the claystone is common after periods of rainfall. It should also be noted that seepage problems can develop after completion of construction. These seepage problems most often result from drainage alterations, landscaping and over-irrigation. In the event that seepage or saturated ground does occur, it has been our experience that they are most effectively i handled on an individual basis. Tectonic Setting The site is located within the seismically active southern California region which is Coast Geotechniical March 8, 2002 W.O. P-347012 1 Page 11 generally characterized by northwest trending Quaternary-age fault zones. Several of these fault zones and fault segments are classified as active by the California Division of Mines and Geology (Alquist-Priolo Earthquake Fault Zoning Act). ni Based on a review of published geologic maps, no known faults transverse the site. The nearest active fault is the offshore Rose Canyon Fault Zone located approximately 6.9 11 miles west of the site. It should be noted that the Rose Canyon Fault is not a continuous, well-defined feature but rather a zone of right stepping en echelon faults. The complex series of faults has been referred to as the Offshore Zone of Deformation (Woodward- Clyde, 1979) and is not fully understood. Several studies suggest that the Newport- Inglewood and the Rose Canyon faults are a continuous zone of en echelon faults 110 (Treiman, 1984). Further studies along the complex offshore zone of faulting may it indicate a potentially greater seismic risk than current data suggests. Other faults which could affect the site include the Coronado Bank, Elsinore, San Jacinto and San Andreas Faults. The proximity of major faults to the site and site parameters are shown on the e, enclosed Earthquake Fault Analysis. 11 Slope Stability No evidence of deep-seated instability was observed on the subject lot. However, the presence of fractured and weathered claystone as encountered in the exploratory trenches significantly reduces the inherent strength of the sedimentary rock. These clayey sedimentary units near the surface are subject to downslope creep. Coast Geotechnical March 8, 2002 W.O. P-347012 Page 13 3) In order to provide a more uniform soils condition for the support of residential foundations and slabs, the cut portion of the building pad area should be undercut and replaced as compacted fill. 4) It is anticipated that utilizing on-site materials for compacted fill will result in an expansion potential in the high range. Therefore, proposed footings and slabs should be designed for an expansive soils condition. A post-tensioned slab is recommended and should be considered for this project. Preliminary design parameters are provided in the foundation section of this report. We have also provided more conventional foundation and slab parameters although such an approach is considered less desirable than a post-tensioned slab. Final foundation parameters should be based on expansion tests performed on actual fill deposits placed during the grading phase. 5) Our experience with this type of lot development and geotechnical conditions suggest that varying degrees of seepage can develop after construction. Post construction seepage and/or saturated ground conditions can adversely affect foundations and concrete flatwork. Therefore, special consideration should be provided for surface and subsurface drainage during the design and construction phases. Additional recommendations during the grading phase may be necessary in this regard. Coast Geotechnical March 8, 2002 W-O. P-347012 Page 14 RECOMMENDATIONS Grading? The proposed cut slope should be constructed as a stabilization fill with a 20 foot wide key excavated a minimum of 2.0 feet (along the outside edge) into competent formational rock. A 15 foot wide key excavated a minimum of 2.0 feet (along the outside edge) into competent formational rock should be constructed along the base of the proposed fill slope. A subdrain should be constructed along the back of the key or bench for the fill slope and stabilization fill (See attached Key, Benching and Subdrain Detail, Plate A). All fill should be benched into the underlying competent formational rock units. The existing earth deposits are generally suitable for reuse, provided they are cleaned of all roots, vegetation, debris and rocks larger than 6.0 inches, and thoroughly mixed. Fill should be placed in 6.0 to 8.0 inch loose lifts, moistened or aerated as required to 2.0-3.0 percent above optimum moisture, and compacted to a minimum of 90 percent of the laboratory maximum dry density. Cut and fill slopes should be constructed at a maximum gradient of 2:1 (horizontal to vertical). A concrete or gunite V-type interceptor drain is recommended along the top of cut slopes in order to intercept sheet flow drainage. Additional recommendations will be presented should any unforeseen conditions be encountered during grading. Imported fill, if necessary, should be approved by this firm. Building Pad - Removals/Recompaction The cut/fill transitional building pad should be undercut and replaced as properly Coast Geotechnical March 8, 2002 W.O. P-347012 Page 15 compacted fill (See Plate B). Removal depths may be estimated on Cross Section A-A. However, deeper removals may be necessary based on actual conditions encountered during grading. Removals should include the entire building pad extending a minimum of 10.0 feet beyond the building footprint. Most of the existing earth deposits are generally suitable for reuse, provided they are cleared of all vegetation, debris and thoroughly mixed. Prior to placement of fill, the base of the removal should be observed by a representative of this firm. Additional overexcavation and recommendations may be necessary at that time. The exposed bottom should be scarified to a minimum depth of 6.0 inches, moistened as required and compacted to a minimum of 90 percent of the laboratory maximum dry density. Fill should be placed in 6.0 to 8.0 inch lifts, moistened or aerated to approximately 2.0 - 3.0 percent above optimum moisture content and compacted to a minimum of 90 percent of the laboratory maximum dry density. Temporary Slopes and Excavation Characteristics Temporary excavations which exceed a vertical height of 3.5 feet should be trimmed to a gradient of 1:1 or less. The Eocene age sedimentary rock units are rippable with conventional heavy earth moving equipment in good working order. Foundations (Conventional) The following design parameters are based on an anticipated expansion potential in the high range and should be incorporated into a post-tensioned slab, where applicable, or a conventional slab design. Conventional footings for the proposed residence should be Coast Geotechnical March 8, 2002 W.O. P-347012 Page 16 a minimum of 15 inches wide and founded a minimum of 30 inches below the lower most adjacent subgrade for one and two story structures. A 12 inch by 12 inch grade beam should be placed across the garage opening. Footings should be reinforced with a minimum of four No. 5 bars, two along the top of the footing and two along the base. Isolated column pads should not be utilized in the foundation design. Footing recommendations provided herein are based upon underlying soil conditions and are not intended to be in lieu of the project structural engineer's design. For design purposes, an allowable bearing value of 2000 pounds per square foot may be used for foundations at the recommended footing depths. The bearing value indicated above is for the total dead and frequently applied live loads. This value may be increased by 33 percent for short durations of loading, including the effects of wind and seismic forces. Resistance to lateral load may be provided by friction acting at the base of foundations and by passive earth pressure. A coefficient of friction of 0.35 may be used with dead- load forces. A passive earth pressure of 250 pounds per square foot, per foot of depth of fill penetrated to a maximum of 2000 pounds per square foot may be used. Slabs on Grade (Conventional Interior and Exterior) Due to the highly expansive nature of the on-site earth materials, varying degrees of Coast Geotechnical March 8, 2002 W.O. P-347012 Page 17 movement can occur within subgrade soils due to moisture fluctuations. Volume changes within soils can result in significant differential pressure exerted against footings and stabs. The following recommendations are presented to reduce potential distress along concrete flatwork. As previously indicated, a post-tensioned slab should be considered. Although less desirable, conventional slab design may be used. However, a minimum of 18 inches of non-expansive compacted fill is recommended under interior slabs. Slabs on grade should be a minimum of 5.0 inches thick and reinforced in both directions with No. 4 bars placed 16 inches on center. The slab should be underlain by a minimum 4.0- inch coarse sand blanket, gravel or crushed rock (3/4 inch maximum). Where moisture sensitive floors are used, a minimum 6.0-mil Visqueen or equivalent moisture barrier should be placed over the sand or rock blanket and covered by an additional two inches of sand. Utility trenches underlying the slab may be backfilled with on-site materials, compacted to a minimum of 90 percent of the laboratory maximum dry density. Slabs including exterior concrete flatwork should be reinforced as indicated above and provided with saw cuts/expansion joints, as recommended by the project structural engineer. All slabs should be cast over dense compacted subgrades which are moistened 3.0 to 5.0 percent above optimum moisture content to a minimum depth of 24 inches. Exterior slabs should be protected from moisture migrating into subsoils by a 2.0 foot deep footing/cutoff wall along the outside of the slab. Additional recommendations for pre-saturation will be provided during the construction phase. Coast Geotechnical March 8, 2002 W.O. P-347012 Page 18 Post-Tensioned Slab The information and recommendations presented herein are not meant to supersede design by a registered structural engineer or civil engineer familiar with post-tensioned slab design. This system should be designed in accordance with the PTI method presented in the applicable Building Code Standards, the following soil related parameters and sound engineering practice. Expansion Index & Potential 93 (High) % Clay 70 Plasticity Index & Plastic Limit 16 and 25 Clay Type Montmorillonite Constant Suction 3.6 Depth to Constant Suction (feet) 7 Thornthwaite Moisture Index (Per Code) - 20 Moisture Velocity 0.7 inches/month eR, (Center Lift) ft. (Per Code) - 5.5 em (Edge Lift) ft. (Per Code) - 2.5 Y,,, (Center Lift) inches 5.31 Ym (Edge Lift) inches 1.1 Slab Perimeter Embedment (inches) 18 (minimum) Modulus of Subgrade Reaction (for slabs) 75 psi per inch Bearing Values (for Footings) 2000 psf The post-tensioned foundation design should consider all imposed loads, including continuous and isolated. Interior isolated loads do not require a specific footing or grade beam, from a geotechnical standpoint. Isolated exterior footings need not be tied to the main foundation system, but should be embedded at least 24 inches below finished grade. Coast Geotechnical March 8, 2002 W.O. P-347012 Page 19 Retaining Walls Cantilever walls (yielding) retaining nonexpansive granular soils may be designed for an active-equivalent fluid pressure of 55 pounds per cubic foot. Restrained walls (nonyielding) should be designed for an "at-rest" equivalent fluid pressure of 60 pounds per cubic foot. Wall footings should be designed in accordance with the foundation design recommendations. All retaining walls should be provided with an adequate backdrainage system. The soil parameters assume a level granular backfill compacted to a minimum of 90 percent of the laboratory maximum dry density. Seismic Considerations Although the likelihood of ground rupture on the site is remote, the property will be exposed to moderate to high levels of ground motion resulting from the release of energy should an earthquake occur along the numerous known and unknown faults in the region. The Rose Canyon/Newport-Inglewood Fault Zone is the nearest known active fault and is considered the design earthquake for the site. A maximum probable event along the offshore segment of the Rose Canyon Fault is expected to produce a peak bedrock horizontal acceleration of 0.25g and a repeatable ground acceleration of 0.168. Coast Geotechnical March 8, 2002 W.O. P-347012 Page 20 Seismic Design Parameters (1997 Uniform Building Code) Soil Profile Type - Sd Seismic Zone - 4 Seismic Source - Type B Near Source Factor (Nj - 1.0 Near source Acceleration Factor (Nj - 1.0 Seismic Coefficients Ca = 0.44 C, = 0.64 Design Response Spectrum TS = 0.582 To = 0.116 Proposed Driveway Previous testing suggests that on-site clayey deposits have an approximate R-value of 5. These materials generally perform poorly as subgrade deposits even with lime treatment or thickened base sections. Satisfactory results have been achieved along Double L Ranch Road and Calle Margarita by the placement of a 2.0 foot section of predominantly granular materials as subgrade deposits. Such an approach reduces the expansion/contraction characteristics due to moisture fluctuation of the clayey soils. However, if importing granular deposits is not an option, then the following alternative is presented. In order to reduce potential distress of the pavement section, a layer of woven geotextile (Mirafi HP 370 or equivalent) should be placed on the prepared subgrade deposits prior to placement of the base materials. The intent is to maintain the structural integrity of the pavement section by reducing the loss of base materials into clayey subgrade soils. Coast Geotechnical March 8, 2002 W.O. P-347012 Page 21 Driveway Section 4 inches of asphaltic paving on 6 inches of select base (Class 2) on 1 layer woven geotextile (Mirafi HP 370 or equivalent) on 12 inches minimum of recompacted clayey soils Subgrade soils should be compacted to the thickness indicated in the structural section and left in a condition to receive base materials. Class 2 base material should have a minimum R-value of 78 and a minimum sand equivalent of 30. Woven geotextile should be placed in accordance with the manufacturers recommendations. Subgrade soils and base materials should be compacted to a minimum of 95 percent, or as near to 95 percent for clayey soils as feasible, of their laboratory maximum dry density. Drainage Specific drainage patterns should be designed by the project civil engineer. However, in general, pad water should be directed away from foundations and around the structure to a suitable discharge location selected by the engineer or architect. Roof water should be collected and conducted to area drains, via non-erodible devices. Pad water should not be allowed to pond or flow onto slopes in an uncontrolled manner. Vegetation adjacent to foundations should be avoided. If vegetation in these areas is desired, seated planter boxes should be considered. Other alternatives may be available, however, the Coast Geotechnical March 8, 2002 W.O. P-347012 Page 22 intent is to reduce moisture from migrating into foundation subsoils and under concrete flatwork. Cut and fill slopes should be planted with drought resistant and erosion controlling vegetation. Irrigation should be limited to that amount necessary to sustain plant life. All drainage devices should be inspected and cleaned on a periodic basis. Observations and Density Testing Structural footing excavations should be observed by a representative of this firm, prior to the placement of steel. Fill should be placed while a representative of this firm is present to observe and test. Plan Review A copy of the grading and building plans should be submitted to this office for review, prior to the initiation of construction. Additional recommendations may be necessary at that time. LIMITATIONS This report is presented with the provision that it is the responsibility of the owner or the owner's representative to bring the information and recommendations given herein to the attention of the project's architects and/or engineers so that they may be incorporated into plans. Coast Geotechnical March 8, 2002 W.O. P-347012 Page 23 If conditions encountered during construction appear to differ from those described in this report, our office should be notified so that we may consider whether modifications are needed. No responsibility for construction compliance with design concepts, specifications or recommendations given in this report is assumed unless on-site review is performed during the course of construction. The subsurface conditions, excavation characteristics and geologic structure described herein are based on individual exploratory excavations made on the subject property. The subsurface conditions, excavation characteristics and geologic structure discussed should in no way be construed to reflect any variations which may occur among the exploratory excavations. Please note that fluctuations in the level of groundwater may occur due to variations in rainfall, temperature and other factors not evident at the time measurements were made and reported herein. Coast Geotechnical assumes no responsibility for variations which may occur across the site. The conclusions and recommendations of this report apply as of the current date. In time, however, changes can occur on a property whether caused by acts of man or nature on this or adjoining properties. Additionally, changes in professional standards may be brought about by legislation or the expansion of knowledge. Consequently, the conclusions and recommendations of this report may be rendered wholly or partially Coast Geotechnical March 8, 2002 W.O. P-347012 Page 24 invalid by events beyond our control. This report is therefore subject to review and should not be relied upon after the passage of two years. The professional judgments presented herein are founded partly on our assessment of the technical data gathered, partly on our understanding of the proposed construction and partly on our general experience in the geotechnical field. Our engineering work and the judgments given meet present professional standards. However, in no respect do we guarantee the outcome of the project. Coast Geotechnical March 8, 2002 W.O. P-347012 Page 25 GENERAL REFERENCES 1. Hays, Walter W., 1980, Procedures for Estimating Earthquake Ground Motions, Geological Survey Professional Paper 1114, 77 pages. 2. Petersen, Mark D. and others (DMG), Frankel, Arthur D. and others (USGS), 1996, Probabilistic Seismic Hazard Assessment for the State of California, California Division of Mines and Geology OFR 96-08, United States Geological Survey OFR 96-706. 3. Seed, H.B., and Idriss, I.M., 1970, A Simplified Procedure for Evaluating Soil Liquefaction Potential: Earthquake Engineering Research Center. 4. Treiman, J.A., 1984, The Rose Canyon Fault Zone, A Review and Analysis, California Division of Mines and Geology. MAPS/AERIAL PHOTOGRAPHS 1. Aerial Photographs, October 18, 1991, Lloyd Subdivision, Scale 1"=200'. 2. California Division of Mines and Geology, 1994, Fault Activity Map of California, Scale 1"=750,000'. 3. Conway and Associates, 2002, Preliminary Grading Plan, Lot 2, Scale 1"=20'. 4. Geologic Map of the Encinitas and Rancho Santa Fe 7.5' Quadrangles, 1996, DMG Open File Report 96-02. 5. San Diego County Topographic/Orthophoto Survey, 1982,Map No. 326-1701, Scale 1"=200'. Coast Geotechnical March 8, 2002 W-O. P-347012 Page 26 DOUBLE LL RANCH ESTATES REFERENCES 1. Barry and Associates, 1990, Preliminary Geotechnical Investigation, Proposed Single Family Residences. Lots 1 through 6, TPM 18031, Encinitas, California. 2. Coast Geotechnical, 1993, Interim Mass Grading Geotechnical Report, Encinitas Tract 87-041, Encinitas, California. 3. Coast Geotechnical, 1993, Pavement Section, From STA 5+20 to 21+00 Double LL Ranch Road and From STA 1+00 to End of Cul-De-Sac of Calle 47, Encinitas, California. 4. Coast Geotechnical, 1993, Structural Section Pavement Design, Double LL Ranch Road and Calle 47, Encinitas Tract 87-041, Encinitas, California. 5. Coast Geotechnical, 1994, Geotechnical Reconnaissance, Proposed Division of 10.8 Acres, Parcels 1 through 4, inclusive, TPM 93-053, Encinitas, California. 6. Coast Geotechnical, 1995, Pavement Section, Lone Jack Road Improvement, Encinitas Tract 87-041, Encinitas, California. 7. Coast Geotechnical, 1995, Addendum Report, Pavement Section and Storm Drain Backfill, Double LL Ranch Estates, Parcel 1 through 4, inclusive, TPM 93-053, Encinitas, California. 8. Coast Geotechnical, 1995, Preliminary Geotechnical Evaluation, Lone Jack Road Improvement, Encinitas Tract 87-041, Encinitas, California. 9. Coast Geotechnical, 1995, Geotechnical Reconnaissance, Double LL Ranch Estates, Lots 1 through 6, inclusive, TPM 93-029, Encinitas, California. 10. Coast Geotechnical, 1995, Rough Grading Report, Double LL Ranch Estates, Parcels 1 through 4, inclusive, TPM 93-053, Encinitas, California. 11. Coast Geotechnical, 1995, Compaction Report, Backfilled Borrow Pit, Portion of Parcels 3 and 4, TPM 93-053, Double LL Ranch Estates, Olivenhain, California. 12. Coast Geotechnical, 1996, General Geotechnical Conditions, Double LL Ranch Estates, Olivenhain, California. Coast Geotechnical March 8, 2002 W.O. P-347012 Page 27 DOUBLE LL RANCH ESTATES REFERENCES (Continued) 13. Coast Geotechnical, 1996, Clarification Letter, Supplemental Exploration, TM 93- 029, Double LL Ranch Estates, Encinitas, California. 14. Coast Geotechnical, 1996, Addendum Report/Grading Plan Review, TM 93-029, Double LL Ranch Estates, Encinitas, California. 15. Coast Geotechnical, 1996, Final Geotechnical Report, Lone Jack Road Improvements, Encinitas Tract 87-041, Encinitas, California. 16. Coast Geotechnical, 1997, Geotechnical Reconnaissance, Double LL Ranch Estates, Lots 1 through 12, inclusive, Tentative Map, Portion of Remainder Parcel (41.29 Acres) of Parcel Map No. 17446, Encinitas, California. 17. Coast Geotechnical, 1997, Geotechnical Reconnaissance, Proposed Division of 13.2 Acres, Lots 1 through 5, inclusive, Encinitas, California. 18. Coast Geotechnical, 1998, Preliminary Geotechnical Investigation, Double LL Ranch Estates, Lots 1 through 12, inclusive, Tentative Map, Portion of Remainder Parcel (41.29 Acres) of Parcel Map No. 17446, Olivenhain, California. 19. Coast Geotechnical, 1998, Final Geotechnical Report, Double LL Ranch Estates, Calle Margarita Northerly Extension, TM 97-100, Encinitas, California. 20. Coast Geotechnical, 1998, Pavement Section, Double LL Ranch Estates, Calle Margarita Northerly Extension, TM 97-100, Encinitas, California. 21. Southern California Soil & Testing, 1983, Geologic Reconnaissance, TPM 18031, Lone Jack Road, San Diego, California. APPENDIX A LABORATORY TEST RESULTS TABLE I Maximum Dry Density and Optimum Moisture Content (Laboratory Standard ASTM D-1557-91) Sample Max. Dry Optimum Location Density Moisture Content cf TP-3 @ 2 ' -4 ' 116 . 7 15 .2 TABLE II Field Dry Density and Moisture Content Sample Field Dry Field Moisture Location Density Content (Ipcf) 0 TP-1 @ 1 . 0 ' 109 . 1 12 . 7 TP-1 @ 1 . 5 ' 106 . 9 14 . 0 TP-1 @ 2 . 5 ' 98 . 0 15 . 6 TP-1 @ 5 . 5 ' 85 . 2 20 . 9 TP-1 @ 7 . 0 ' 95 . 4 24 . 8 TP-1 @ 10 . 0 ' 99 . 4 18 . 9 TP-2 @ 1 . 0 ' 102 . 2 11 . 8 TP-2 @ 4 . 0 ' 105 . 1 18 . 2 TP-2 @ 8 . 0 ' 96 . 1 14 . 2 TP-3 @ 1 . 0 ' 115 . 3 16 . 2 TP-3 @ 4 . 0 ' 99 .4 18 . 9 TP-3 @ 8 . 5 ' 103 . 3 13 . 7 TABLE III Expansion Index Test Results Sample Location Expansion Index T-3 @ 2 ' -4 ' 94 (High) TABLE IV Direct Shear Test Results Sample Angle Of Apparent Location Int . Fric . (deg. ) Cohesion (psf) T-1 @ 5 . 5 ' 28 166 P-347012 LOG OF EXPLORATORY TRENCH NO. 1 PROJECT NO. P-347012 e DATE EXCAVATED: 0 1-30-02 z SURFACE ELEV.: 250' 3 H OU u w Q a w a � LOGGED BY: MB w Q ::x � � Q c7 250.00 DESCRIPTION 0.00 SOIL(Qs): Dk.brn. sandy CLAY,damp,stiff,expansive,blocky in 1' 109.1 12.7 upper 106.9 14.0 248.00 � 2.00 traditional Contact 98.0 15.6 e: Cn DEL MAR FORMATION(Td): Whitish tan claystone,weathered, 246.00 lxaiwi O slightly sandy,soft,damp 4.00 =is;nfI N Irregular caliche stringers 85.2 20.9 244.00 6.00 t DEL MAR FORMATION(Td):Pale green claystone,slightly sandy, C7 fractured,v.damp but no groundwater 95.4 24.8 IMMIX z 242.00 iiY�l 8.00 iiy3ii• - tYi1 Nt:. IAIR% 240.00 201", 238.00 99.4 18.9 10.00 }���lk. rutws 238.00 i 12.00 I TRENCH SKETCH N45W,45'LONG (Weathered) I Td PAGE) 1 01; 1 COAST GEOTECHNICAL LOG OF EXPLORATORY TRENCH NO. 2 PROJECT NO. P-347012 ,a DATE EXCAVATED: 01-30-02 o � z w g ¢ r- SURFACE ELEV.: 235' o w w LOGGED BY: MB 235.00 DESCRIPTION 0.00 SOIL(Qs): Dk.brn.sandy CLAY,damp,stir,expansive,blocky in 102.2 11.8 upper F 233.00 b 2.00 Graditional Contact L MAR FORMATION Td Whitish tan cla 231.00 DE s-•!—! ( )� stone,weathered,clay stone, 18.2 4.00 ; ;r slightly sandy,soft,damp al iv 229.00 =. 6.00 fr�i ' DEL MAR FORMATION(Td):Pale green claystone,slightly sandy, ;3; 111 fractured,v.damp but no groundwater 227.00 96.1 14.2 O 8.00 ril O 225.00 z 10.00 !03 1-M.Mli 223.00 MeAd: 12.00 i#,i:0i" KE, i3 221.00 !�ill 14.00 IN 1 j 1. TRENCH SKETCH N80E, 30'LONG QS �.z_ Td(weathered) ___. _-_ _ _ _ _ Td I / PAGE I OF i COAST GEOTECHNICAL LOG OF EXPLORATORY TRENCH NO. 3 PROJECT NO. P-347012 DATE EXCAVATED: 01-30-02 SURFACE ELEV.: 220' 3 w u LOGGED BY: MB Q 0 220.00 DESCRIPTION 0.00 SOIL(Qs): Dk.bm. sandy CLAY,damp,stir,expansive,blocky in upper F 115.3 16.2 218.00 2.00 -o Graditional Contact a� i !?i'• DEL MAR FORMATION(Td): Whitish tan claystone,weathered, °M'ti�d'7 216.00 i:viw:v slightly sandy,soft,damp 99.4 18.9 4.00 ARIZ 214.00 6.00 a!f DEL MAR FORMATION(Td):Pale green claystone,slightly sandy, 1}i117J1'r,: IiIi?71 o � fractured,v.damp but no groundwater O �7 212.00 z s.00 ivi: ::• 103.3 13.7 ,.��...•:_ 1AIAH. 210.00 10101'r ,� e� •tr 10.00 `�...�...�.. `}}ti�lti�l1{ 1{�itidly i 208.00 j 12.00 TRENCH SKETCH N75W,30'LONG Td(weathered) ' Td PAGE, 1 OF ► COAST GEOTECHNICAL FILL SLOPE ---------------- PROJECT I TO I LINE ----- FROM TOE OF SLOPE TO COMPETENT MATE RIAL LL' EXISTING =---- ----- GROUND SURFACE REMOVE UNSUITABLE MATERIAL 5 an: BENCH 2' MIN. 16@ MIN KEY LOWEST DEPTH BENCH (KEY). W MIN. OVERLAP 3/40-1-1/20 CLEAN GRAVEL 6• MIN. 12 4 GRAVEL (If Wfl. MIN.) COVER a 0 4- 0 4 ;I ATED NON-PERFORATED PERFORATED 40 NONPERFORATEID PIPE PIlPE LATERAL TO SLOPE FACE AT lo(r INTERVALS FILTER FABRIC ENVELOPE (MIRAFI 40 MIN.' 140N OR APPROVED BEDDING EQUIVALENT)• SUBDRAIN TRENCH DETAIL KEY, BENCHING AND SUBDRAIN DETAIL PLATE A TRANSITION LOT DETAILS CUT-FILL LOT EXISTING ................... ............ GROUND SURFACE - -- z (J _N W O , I C lii wr`. I F-' I r � I I ' f 11 I u h Irrl s u I 1 II rl / I I I I ral i < �I1 I I I s I 1 3 I z 1 0 r I I lyl o 1 r 1 v , o I w , yJ I, I, �rrl I r � 3 I o r I u wl �4a1 I 3i L, I I r�/ I , I \I I < I a� r I ' I o r 0 0 N N � N N ......__ ._.. ...__.___.�...�._..._v+-mow.....�_..........._....., a z _o cri oA � C 0 � O O W x pow HJ/l lj'w�O a�i'`'a�s V>l K <`i�'i'a/I./';"/r� �1•'z.'./' l l•d t.,�'I I!j ap,~N' Pa jS uj 10 w a I►(O i i(l-• 9 ti /I 7I'� o N z y' UP C4 04'o 0 CA CV ID zr 14+1 0 HONV6 7 318n00 woo. 0 I I I I I /►► ' ! j — APPENDIX B CALIFORNIA FAULT MAP NELSON 1100 1000 900 800 700 600 500 400 300 200 100 o � 0 e, SITE -100 -400 -300 -200 -100 0 100 200 300 400 500 600 *********************** * * U B C S E I S * * * Version 1.03 * * *********************** COMPUTATION OF 1997 UNIFORM BUILDING CODE SEISMIC DESIGN PARAMETERS JOB NUMBER: P-347012 DATE: 03-08-2002 JOB NAME: NELSON FAULT-DATA-FILE NAME: CDMGUBCR.DAT SITE COORDINATES: SITE LATITUDE: 33.0658 SITE LONGITUDE: 117.2206 UBC SEISMIC ZONE: 0.4 UBC SOIL PROFILE TYPE: SD NEAREST TYPE A FAULT: NAME: ELSINORE-JULIAN DISTANCE: 39.3 km NEAREST TYPE B FAULT: NAME: ROSE CANYON DISTANCE: 11.1 km NEAREST TYPE C FAULT: NAME: DISTANCE: 99999.0 km SELECTED UBC SEISMIC COEFFICIENTS: Na: 1.0 Nv: 1.0 Ca: 0.44 Cv: 0.64 Ts: 0.582 To: 0.116 --------------------------- SUMMARY OF FAULT PARAMETERS Page 1 ------------------------------------------------------------------------------ I APPROX. ISOURCE I MAX. I SLIP I FAULT ABBREVIATED IDISTANCEI TYPE I MAG. I RATE I TYPE FAULT NAME I (km) I (A,B,C) I (Mw) I (mm/yr) (SS,DS,BT) ROSE CANYON 1 11.1 I B l 6.9 I 1.50 I SS NEWPORT-INGLEWOOD (Offshore) I 21.9 I B I 6.9 I 1.50 I SS CORONADO BANK I 34.9 I B I 7.4 I 3.00 I SS ELSINORE-JULIAN I 39.3 I A I 7.1 I 5.00 I SS ELSINORE-TEMECULA I 39.6 i B I 6.8 I 5.00 I SS EARTHQUAKE VALLEY I 60.9 I B I 6.5 I 2.00 I SS ELSINORE-GLEN IVY I 65.3 I B I 6.8 I 5.00 I SS PALOS VERDES I 71.0 I B I 7.1 I 3.00 I SS SAN JACINTO-ANZA I 75.8 I A I 7.2 I 12.00 I SS SAN JACINTO-COYOTE CREEK I 79.4 I B I 6.8 I 4.00 I SS SAN JACINTO-SAN JACINTO VALLEY I 80.1 I B I 6.9 I 12.00 I SS ELSINORE-COYOTE MOUNTAIN I 80.8 I B I 6.8 I 4.00 ► SS NEWPORT-INGLEWOOD (L.A.Basin) I 88.8 I B I 6.9 I 1.00 I SS CHINO-CENTRAL AVE. (Elsinore) I 89.6 I B I 6.7 I 1.00 I DS ELSINORE-WHITTIER I 95.8 I B I 6.8 I 2.50 I SS SAN JACINTO - BORREGO I 96.8 I B I 6.6 I 4.00 I SS SAN JACINTO-SAN BERNARDINO i 105.8 I B I 6.7 I 12.00 I SS SAN ANDREAS - Southern I 109.3 I A I 7.4 I 24.00 I SS PINTO MOUNTAIN I 119.7 I B I 7.0 I 2.50 I SS SUPERSTITION MTN. (San Jacinto) I 121.3 I B I 6.6 I 5.00 I SS SAN JOSE I 122.9 I B I 6.5 I 0.50 I DS BURNT MTN. I 125.5 I B I 6.5 I 0.60 I SS CUCAMONGA I 125.9 I A I 7.0 i 5.00 I DS SIERRA MADRE (Central) I 127.1 I B I 7.0 I 3.00 I DS ELMORE RANCH I 127.4 I B I 6.6 ! 1.00 I SS SUPERSTITION HILLS (San Jacinto) I 129.0 I B ( 6.6 I 4.00 I SS EUREKA PEAK I 129.8 I B I 6.5 I 0.60 I SS ELSINORE-LAGUNA SALADA I 130.4 ( B I 7.0 I 3.50 I SS NORTH FRONTAL FAULT ZONE (West) I 131.9 ( B I 7.0 I 1.00 I DS CLEGHORN I 134.4 I B I 6.5 ( 3.00 I SS NORTH FRONTAL FAULT ZONE (East) I 136.9 I B I 6.7 ( 0.50 I DS SAN ANDREAS - 1857 Rupture I 141.4 I A I 7.8 I 34.00 I SS RAYMOND I 142.6 I B I 6.5 I 0.50 I DS CLAMSHELL-SAWPIT I 142.6 I B I 6.5 I 0.50 I DS LANDERS I 143.2 I B I 7.3 I 0.60 I SS BRAWLEY SEISMIC ZONE I 144.5 I B i 6.5 I 25.00 I SS VERDUGO I 147.0 I B I 6.7 I 0.50 I DS HELENDALE - S. LOCKHARDT I 148.7 ( B I 7.1 1 0.60 I SS HOLLYWOOD I 150.2 I B I 6.5 I 1.00 I DS LENWOOD-LOCKHART-OLD WOMAN SPRGS ( 153.3 I B I 7.3 I 0.60 I SS IMPERIAL I 154.8 I A I 7.0 I 20.00 I SS EMERSON So. - COPPER MTN. I 155.1 I B I 6.9 I 0.60 1 SS JOHNSON VALLEY (Northern) I 156.8 I B I 6.7 I 0.60 I SS SANTA MONICA I 158.1 I B I 6.6 I 1.00 I DS MALIBU COAST I 162.7 I B I 6.7 I 0.30 I DS PISGAH-BULLION MTN.-MESQUITE LK I 164.2 I B I 7.1 I 0.60 I SS --------------------------- SUMMARY OF FAULT PARAMETERS --------------------------- Page 2 ------------------------------------------------------------------------------ I APPROX. ISOURCE I MAX. I SLIP I FAULT ABBREVIATED IDISTANCEI TYPE I MAG. I RATE I TYPE FAULT NAME I (km) I (A,B,C) I (Mw) I (mm/yr) (SS,DS,BT) SIERRA MADRE (San Fernando) ( 167.9 I B I 6.7 I 2.00 I DS CALICO - HIDALGO I 169.2 I B I 7.1 I 0.60 I SS SAN GABRIEL I 170.7 I B I 7.0 ( 1.00 ( SS ANACAPA-DUME I 171.2 I B I 7.3 I 3.00 I DS SANTA SUSANA I 183.5 I B I 6.6 I 5.00 I DS HOLSER I 192.5 I B ( 6.5 I 0.40 I DS SIMI-SANTA ROSA I 200.4 I B I 6.7 I 1.00 I DS OAK RIDGE (Onshore) I 201.0 I B I 6.9 I 4.00 I DS GRAVEL HILLS - HARPER LAKE I 202.9 I B I 6.9 I 0.60 I SS SAN CAYETANO ) 209.4 I B I 6.8 I 6.00 I DS BLACKWATER I 218.6 I B I 6.9 I 0.60 I SS VENTURA - PITAS POINT I 228.6 ( B I 6.8 I 1.00 I DS SANTA YNEZ (East) I 229.2 I B I 7.0 I 2.00 I SS SANTA CRUZ ISLAND I 237.2 I B I 6.8 I 1.00 I DS M.RIDGE-ARROYO PARIDA-SANTA ANA I 239.2 I B I 6.7 I 0.40 I DS RED MOUNTAIN I 242.7 I B I 6.8 I 2.00 I DS GARLOCK (West) I 244.4 I A I 7.1 I 6.00 I SS PLEITO THRUST I 250.5 I B I 6.8 I 2.00 I DS BIG PINE 1 256.5 I B I 6.7 I 0.80 I SS GARLOCK (East) I 257.8 I A I 7.3 I 7.00 I SS WHITE WOLF I 270.5 I B I 7.2 I 2.00 I DS SANTA ROSA ISLAND I 272.0 I B I 6.9 I 1.00 ( DS SANTA YNEZ (West) I 274.6 I B I 6.9 I 2.00 I SS So. SIERRA NEVADA I 281.9 I B I 7.1 I 0.10 I DS OWL LAKE I 284.3 I B I 6.5 I 2.00 I SS PANAMINT VALLEY I 284.6 I B I 7.2 I 2.50 I SS LITTLE LAKE I 285.7 I B I 6.7 I 0.70 I SS TANK CANYON I 286.4 I B ( 6.5 I 1.00 I DS DEATH VALLEY (South) I 291.8 I B I 6.9 I 4.00 I SS LOS ALAMOS-W. BASELINE 1 316.9 I B I 6.8 I 0.70 I DS LIONS HEAD I 334.4 I B I 6.6 i 0.02 I DS DEATH VALLEY (Graben) I 334.6 I B I 6.9 I 4.00 I DS SAN LUIS RANGE (S. Margin) I 344.1 I B I 7.0 I 0.20 I DS SAN JUAN I 344.6 I B I 7.0 I 1.00 I SS CASMALIA (Orcutt Frontal Fault) I 352.5 I B I 6.5 I 0.25 I DS OWENS VALLEY I 354.7 I B I 7.6 I 1.50 I SS LOS OSOS I 374.1 { B I 6.8 ( 0.50 I DS HUNTER MTN. - SALINE VALLEY I 379.8 I B I 7.0 I 2.50 I SS HOSGRI I 380.2 I B I 7.3 I 2.50 I SS DEATH VALLEY (Northern) I 388.4 I A I 7.2 I 5.00 I SS INDEPENDENCE I 390.6 I B I 6.9 I 0.20 I DS RINCONADA I 395.0 I B I 7.3 I 1.00 I SS BIRCH CREEK I 447.1 I B I 6.5 I 0.70 I DS SAN ANDREAS (Creeping) I 451.1 I B I 5.0 I 34.00 I SS WHITE MOUNTAINS I 451.4 I B I 7.1 I 1.00 I SS DEEP SPRINGS I 469.6 I B I 6.6 I 0.80 I DS --------------------------- SUMMARY OF FAULT PARAMETERS --------------------------- Page 3 ------------------------------------------------------------------------------ APPROX. ISOURCE I MAX. I SLIP I FAULT ABBREVIATED IDISTANCEI TYPE I MAG• I RATE I TYPE FAULT NAME I (km) I (A,B,C) I (Mw) I (mm/yr) I (SS,DS,BT) DEATH VALLEY (N. of Cucamongo) I 474.1 I A I 7.0 { 5.00 I SS ROUND VALLEY (E. of S.N.Mtns. ) I 482.4 I B I 6.8 I 1.00 I DS FISH SLOUGH I 489.9 I B I 6.6 I 0.20 I DS HILTON CREEK I 508.6 { B I 6.7 I 2.50 I DS HARTLEY SPRINGS I 533.1 I B I 6.6 I 0.50 I DS ORTIGALITA I 535.3 I B I 6.9 I 1.00 I SS CALAVERAS (So.of Calaveras Res) I 541.0 I B { 6.2 I 15.00 I SS MONTEREY BAY - TULARCITOS I 543.8 I B I 7.1 { 0.50 I DS PALO COLORADO - SUR I 544.9 I B 1 7.0 I 3.00 I S5 QUIEN SABE I 554.2 I B I 6.5 I 1.00 I SS MONO LAKE I 569. 1 I B I 6.6 i 2.50 I DS ZAYANTE-VERGELES I 572.8 I B J 6.8 I 0.10 I SS SAN ANDREAS (1906) I 578.0 { A I 7.9 I 24.00 I SS SARGENT I 578.1 I B I 6.8 I 3.00 I SS ROBINSON CREEK I 600.5 I B { 6.5 I 0.50 I DS SAN GREGORIO I 619.2 I A { 7.3 I 5.00 I SS GREENVILLE I 627.6 { B I 6.9 I 2.00 I SS MONTE VISTA - SHANNON I 628.2 I B I 6.5 I 0.40 I DS HAYWARD (SE Extension) I 628.2 I B I 6.5 ► 3.00 I SS ANTELOPE VALLEY I 640.9 I B I 6.7 I 0.80 I DS HAYWARD (Total Length) I 647.9 I A I 7.1 I 9.00 I SS CALAVERAS (No.of Calaveras Res) { 647.9 I B I 6.8 I 6.00 I SS GENOA I 666.4 I B I 6.9 I 1.00 I DS CONCORD - GREEN VALLEY I 695.6 I B I 6.9 J 6.00 I SS RODGERS CREEK I 734.4 I A I 7.0 I 9.00 I SS WEST NAPA I 735.3 I B I 6.5 I 1.00 J SS POINT REYES ( 753.5 I B I 6.8 I 0.30 I DS HUNTING CREEK - BERRYESSA { 757.6 { B I 6.9 I 6.00 I SS MAACAMA (South) I 797.1 I B I 6.9 I 9.00 I SS COLLAYOMI I 814.0 I B I 6.5 I 0.60 I SS BARTLETT SPRINGS I 817.4 I A I 7.1 I 6.00 I SS MAACAMA (Central) i 838.8 I A I 7.1 I 9.00 I SS MAACAMA (North) I 898.3 I A I 7.1 J 9.00 I SS ROUND VALLEY (N. S.F.Bay) I 904.3 I B I 6.8 I 6.00 I SS BATTLE CREEK I 927.0 I B I 6.5 I 0.50 I DS LAKE MOUNTAIN I 962.8 I B { 6.7 I 6.00 I SS GARBERVILLE-BRICELAND I 979.9 I B I 6.9 I 9.00 I SS MENDOCINO FAULT ZONE 1 1036.4 I A I 7.4 I 35.00 I DS, LITTLE SALMON (Onshore) 1 1042.8 I A I 7.0 I 5.00 I DS MAD RIVER 1 1045.6 I B I 7.1 I 0.70 I DS CASCADIA SUBDUCTION ZONE 1 1050.1 I A I 8.3 I 35.00 I DS McKINLEYVILLE 1 1056.0 I B J 7.0 I 0.60 I DS TRINIDAD 1 1057.5 I B I 7.3 I 2.50 I DS FICKLE HILL 1 1058.0 I B I 6.9 I 0.60 I DS O LO O h±i � Q LO W � M a M � w o U N O a �J O 1--1 LO O W O Q o IX) o LO o LO o N N O O (6) uoi}eaapooy leiloadg APPENDIX C GRADING GUIDELINES Grading should be performed to at least the minimum requirements of the governing agencies, Chapter 33 of the Uniform Building Code, the geotechnical report and the guidelines presented below. All of the guidelines may not apply to a specific site and additional recommendations may be necessary during the grading phase. Site Clearinq Trees, dense vegetation, and other deleterious materials should be removed from the site. Non-organic debris or concrete may be placed in deeper fill areas under direction of the Soils engineer. Subdrainage 1. During grading, the Geologist and Soils Engineer should evaluate the necessity of placing additional drains (see Plate A). 2. All subdrainage systems should be observed by the Geologist and Soils Engineer during construction and prior to covering with compacted fill. 3. Consideration should be given to having subdrains located by the project surveyors. Outlets should be located and protected. Treatment of Existing Ground 1. All heavy vegetation, rubbish and other deleterious materials should be disposed of off site. 2. All surficial deposits including alluvium and colluvium should be removed unless otherwise indicated in the text of this report. Groundwater existing in the alluvial areas may make excavation difficult. Deeper removals than indicated in the text of the report may be necessary due to saturation during winter months. 3. Subsequent to removals, the natural ground should be processed to a depth of six inches, moistened to near optimum moisture conditions and compacted to fill standards. Fill Placement 1. Most site soil and bedrock may be reused for compacted fill; however, some special processing or handling may be required (see report). Highly organic or contaminated soil should not be used for compacted fill. (1) 2. Material used in the compacting process should be evenly spread, moisture conditioned, processed, and compacted in thin lifts not to exceed six inches in thickness to obtain a uniformly dense layer. The fill should be placed and compacted on a horizontal plane, unless otherwise found acceptable by the Soils Engineer. 3. If the moisture content or relative density varies from that acceptable to the Soils engineer, the Contractor should rework the fill until it is in accordance with the following: a) Moisture content of the fill should be at or above optimum moisture. Moisture should be evenly distributed without wet and dry pockets. Pre- watering of cut or removal areas should be considered in addition to watering during fill placement, particularly in clay or dry surficial soils. b) Each six inch layer should be compacted to at least 90 percent of the maximum density in compliance with the testing method specified by the controlling governmental agency. In this case, the testing method is ASTM Test Designation D-1557-91. 4. Side-hill fills should have a minimum equipment-width key at their toe excavated through all surficial soil and into competent material (see report) and tilted back into the hill (Plate A). As the fill is elevated, it should be benched through surficial deposits and into competent bedrock or other material deemed suitable by the Soils Engineer. 5. Rock fragments less than six inches in diameter may be utilized in the fill, provided: a) They are not placed in concentrated pockets; b) There is a sufficient percentage of fine-grained material to surround the rocks; c) The distribution of the rocks is supervised by the Soils Engineer. 6. Rocks greater than six inches in diameter should be taken off site, or placed in accordance with the recommendations of the Soils Engineer in areas designated as suitable for rock disposal. 7. In clay soil large chunks or blocks are common; if in excess of six (6) inches minimum dimension then they are considered as oversized. Sheepsfoot compactors or other suitable methods should be used to break the up blocks. (2) 8. The Contractor should be required to obtain a minimum relative compaction of 90 percent out to the finished slope face of fill slopes. This may be achieved by either overbuilding the slope and cutting back to the compacted core, or by direct compaction of the slope face with suitable equipment. If fill slopes are built "at grade" using direct compaction methods then the slope construction should be performed so that a constant gradient is maintained throughout construction. Soil should not be "spilled" over the slope face nor should slopes be "pushed out" to obtain grades. Compaction equipment should compact each lift along the immediate top of slope. Slopes should be back rolled approximately every 4 feet vertically as the slope is built. Density tests should be taken periodically during grading on the flat surface of the fill three to five feet horizontally from the face of the slope. In addition, if a method other than over building and cutting back to the compacted core is to be employed, slope compaction testing during construction should include testing the outer six inches to three feet in the slope face to determine if the required compaction is being achieved. Finish grade testing of the slope should be performed after construction is complete. Each day the Contractor should receive a copy of the Soils Engineer's "Daily Field Engineering Report" which would indicate the results of field density tests that day. 9. Fill over cut slopes should be constructed in the following manner: a) All surficial soils and weathered rock materials should be removed at the cut-fill interface. b) A key at least 1 equipment width wide (see report) and tipped at least 1 foot into slope should be excavated into competent materials and observed by the Soils Engineer or his representative. c) The cut portion of the slope should be constructed prior to fill placement to evaluate if stabilization is necessary, the contractor should be responsible for any additional earthwork created by placing fill prior to cut excavation. 10. Transition lots (cut and fill) and lots above stabilization fills should be capped with a four foot thick compacted fill blanket (or as indicated in the report). 11. Cut pads should be observed by the Geologist to evaluate the need for overexcavation and replacement with fill. This may be necessary to reduce water infiltration into highly fractured bedrock or other permeable zones,and/or due to differing expansive potential of materials beneath a structure. The overexcavation should be at least three feet. Deeper overexcavation may be recommended in some cases. (3) 12. Exploratory backhoe or dozer trenches still remaining after site removal should be excavated and filled with compacted fill if they can be located. Grading Observation and Testing 1. Observation of the fill placement should be provided by the Soils Engineer during the progress of grading. 2. In general, density tests would be made at intervals not exceeding two feet of fill height or every 1,000 cubic yards of fill placed. This criteria will vary depending on soil conditions and the size of the fill. In any event, an adequate number of field density tests should be made to evaluate if the required compaction and moisture content is generally being obtained. 3. Density tests may be made on the surface material to receive fill, as required by the Soils Engineer. 4. Cleanouts, processed ground to receive fill, key excavations,subdrains and rock disposal should be observed by the Soils Engineer prior to placing any fill. It will be the Contractor's responsibility to notify the Soils Engineer when such areas are ready for observation. 5. A Geologist should observe subdrain construction. 6. A Geologist should observe benching prior to and during placement of fill. Utility Trench Backfill Utility trench backfill should be placed to the following standards: 1. Ninety percent of the laboratory standard if native material is used as backfill. 2. As an alternative, clean sand may be utilized and flooded into place. No specific relative compaction would be required; however, observation, probing, and if deemed necessary, testing may be required. 3. Exterior trenches, paralleling a footing and extending below a 1:1 plane projected from the outside bottom edge of the footing, should be compacted to 90 percent of the laboratory standard. Sand backfill, unless it is similar to the inplace fill, should not be allowed in these trench backfill areas. Density testing along with probing should be accomplished to verify the desired results. (4) GENERAL CONSIDERATIONS (For An Expansive Soils Condition) Expansive Soils Expansive soils are soils that undergo volume changes with moisture content variations. The "active" soil zone generally varies from 2 to 4 feet below the ground surface. However, this zone can be increased due to poor drainage patterns and/or heavy irrigation. Long term maintenance becomes a critical factor. Cracking and/or movement of hard surfaces (e.g. floor slab, patios, walkway, sidewalks and pavement) are common. In new construction, soil movement often causes minor cracking of slabs and walls. Expect these cracks; they are usually minor and do not indicate structural distress. Contemporary foundation design and construction seek to reduce cracking to tolerable limits. The economics of construction make it impracticable to construct "crack-free" structures and slabs. Further, cracking in new structures can be caused by expansion and contraction of concrete, drying and warping of lumber, or other factors unrelated to soil movement. Structural design seeks to minimize cracking and uplifts within structures. Some design characteristics and their effects follow: 1) Deepened foundations increase resistance to movement and act as moisture barriers to minimize fluctuations beneath slabs. 2) Increased steel reinforcement in footings and slabs adds strength and minimizes separation along cracks. 3) Moisture conditioned soil expands before slabs are poured, thereby minimizing potential for expansion beneath slabs. 4) Finish lot grading directs water away from foundations. Maintenance Maintenance plays a crucial role in long-term relief from the effects of expansive soil. Maintenance is the responsibility of the owner and/or maintenance firm. Suggested do's and dont's should be applied not only to properties with expansive soils but to all properties: (Page 1 of 2) DO 1. Direct drainage away from structures and improvements to the street. 2. Consider the possible presence of expansive soil when constructing patios, sidewalks, concrete flatwork, etc.. 3. Consider placing a continuous concrete apron (walkway) around the perimeter of the structure. Consider eavetrough, roof gutter, and area drain systems to keep water away from the soil adjacent to building foundations and other improvements. DO NOT 1. Do not allow water to pond or collect near the foundation. 2. Do not construct planters or place in-ground plants next to the foundation. 3. Do not irrigate more than necessary to maintain plant life and stabilize soil moisture. 4. Do not place loose soil near the foundation. Summary Expansive soil can cause significant damage. Current design and construction seek to minimize this effect. Proper maintenance plays a crucial role in preventing damage. (Page 2 of 2) ENGINEERING SERVICES DEP City o ART r MENT -Encinitas Capital Improvement Projects District Support Services Field Operati Sand Replenishment/Stormw ter Coomplan es i Subdivision Engineering February 23, 2004 Traffic Engineering Attn: MBNA DEPOSIT SERVICES P.O. Box 15103 Wilmington, DE 19850-5103 RE: Nelson, K. Scott 1114 Double LL Ranch Road APN 264-241-15 Grading Permit 7533-GI Release of security Permit 7533- GI authorized earthwork, private drainage improvements, and erosion control, all as necessary to build described project. Final, acceptance, and warrant inspections have all been completed to the satisfaction of the Field O eration Therefore, release of the remainder of the security deposit is merited. y P s Division. The following Certificate of Deposit Account has been cancelled by the Fin Services Manager and is hereby released for payment to the depositor. ancial Account#420747303 in the amount of S 56,800.00. The document originals are enclosed. Should you have any questions or concerns, contact Debra Geishart at (760) 633-2779 or in writing, attention the Engineering please Department. Sincerely, f Masih Maher Senior Civil Engineer ay Lembach Subdivision Engineering Finance Manager Financial Services CC: Jay Lembach, Finance Manager Scott K. Nelson Debra Geishart File TEL 760-633-2600 / FAX 760 633 2627 505 S. Vulcan Avenue, Encinitas, California 92024-3633 TDD 760-633-2700 7*vl� recycled paper