The URL can be used to link to this page

Home My WebLink AboutS2018-0206 - SoilsS% -ON LO IS ca lio MAR 8 2019 iii M C CARTHY CONSULTING, INC March 7, 2019 Mr. Ron Hsiu File No: 8299-10 Wyss Group Report No: 20190307-4 196 Technology Drive, Suite I Irvine, California 92618 Subject: Response to City - Residential Plan Review Comments New Spa and Drainage 18 Catania Newport Coast, California Plan Check No: 2676-2018 Submitted herein is our response to the City of Newport Beach in their Plan Review Comments dated November 14, 2018. Comment 12 in the City Plan Review is addressed below. RESPONSE TO CITY REVIEW Comment 12: "Submit shoring design drawings and calculations by a California licensed civil engineer when the excavation is deeper than 3ft and the distance from the pool excavation to the property line is less than the depth of the excavation." Response: The planned spa footing cut will be 5.5 feet deep at a distance of approximately 3.5 feet from the low -height top of slope wall. A cross section is provided in Figure 1. An analysis of the spa foundation cut using Janbu Dimensionless Parameters per the Harvard Soil Mechanics Series No. 46 was performed. The calculations are provided in Figure 2 and indicate a Factor of Safety of 2.1 for the temporary excavation. The planned excavation cuts into the existing engineered fill materials will not require shoring at the anticipated maximum height of 5.5 feet. Per Figure 1, a 1:1 cut above a 4 foot vertical is recommended per the referenced reports. LIMITATIONS This review and response has been conducted in accordance with generally accepted practice in the engineering geologic and soils engineering field. No further warranty, expressed or implied, is made as to the conclusions and professional advice included in this report. Conclusions and recommendations presented are based on subsurface conditions encountered and are not 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 Phone 949 629 2539 1 email info@rmccarthyconsulting.com March 7, 2019 File No: 8299-10 Report No: 20190307-4 Page: 2 meant to imply that we have control over the natural or existing physical site conditions. The recommendations of the referenced report, including limitations, remain as stated unless specifically superseded herein. Thank you for this opportunity to be of service. If you have any questions, please contact this office. Respectfully submitted, R MCCARTHY CONSULTING, INC. Rob 3.cCarthy Principal Engineer, G.E.2490 Registration Expires 3-31-20 Date Signed: 3/7/19 Attachment: References Figure 1 - Cross Section Rotational Stability Analysis Calculations and Support Data 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 949-629-2539 March 7, 2019 REFERENCES File No: 8299-10 Report No: 20190307-4 Page: 3 1. LCW Group, 2018, "Chen Residence, Landscape Construction Plan, 18 Catania, Newport Coast, CA, 92657," Sheet LC -1.01, June 25. 2. California Building Code, 2016 Edition. 3. City of Newport Beach, Community Development Department, Building Division, 2018, "Over the Counter Geotechnical Report Review Checklist, New Pool and Spa, 18 Catania," November 14. 4. Department of the Navy, 1982, NAVFAC DM -7.1, Soil Mechanics, Design Manual 7.1, Naval Facilities Engineering Command. 5. Goffman, McCormick & Urban, Inc., 1999, "Retaining Wall Excavation, Wall 'C, Lots 37 through 42, Tract 15705, Newport Coast," Project 98-44, Permit No. GB980156, Site Address: 20868 Vista Ridge Road, February 22. 6. Goffman, McCormick & Urban, Inc., 2000, "Report of Geotechnical Observation and Testing of Precise Grading and Utility Trench and Retaining Wall Backfill, Lots 23 through 31, Tract 15705, Newport Coast, California, prepared for Shea Homes," Project 98-44, Precise Grading Permit: GB980153, Project Address: 20878 Vista Ridge Road, January 7. 7. Goffman, McCormick & Urban, Inc., 2001, "Report of Geotechnical Observation and Testing of Precise Grading and Utility Trench and Retaining Wall Backfill, Lots 32, and 36 through 42, Tract 15705, Newport Coast, California, prepared for Shea Homes," Project 98-44, Precise Grading Permit: GB980133 (Models), GB980153 (Production), Project Address: 20878 Vista Ridge Road, March 30. 8. Janbu, Nilmar, 1951, "Stability Analysis of Slopes with Dimensionless Parameters," Harvard Soil Mechanics Series No. 46, January. 9. NorCal Engineering, 2013, "Geotechnical Engineering Investigation, Remodel and Addition to Single Family Residence, 27 Catania, Newport Coast, Newport Beach, California, prepared for Mohammed Namazian, 8 Venezia, Newport Coast, California 92657," Project Number 17182-13, December 31. 10. R McCarthy Consulting, Inc., 2019, "Geotechnical Recommendations, Limited Geotechnical Investigation for Spa, 18 Catania, Newport Coast, California, Plan Check No.: 2676-2018," File No: 8299-00, Report No: 20190110-1, January 10. 11. R McCarthy Consulting, Inc., 2018, "Geotechnical Investigation, Proposed Spa, 18 Catania, Tract 15705, Lot 33, Newport Coast, California, APN: 478-162-20," File No: 8299-00, Report No: 20181126-2, December 11. 12. R McCarthy Consulting, Inc., 2018, "Response to 1st City Review, Limited Geotechnical Investigation for Spa, 18 Catania, Newport Coast, California, Plan Check No: 2676- 2018," File No: 8299-00, Report No: 20181211-1, December 11. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 949-629-2539 (zXI3 r`,r1k AG- L 1?,,:P2- snit K�3!I�B2i c(' 5 PA• EX c piVA,'r16 Al t a-) 11 -r� ROTATIONAL SLOPE STABILITY ANALYSIS, USING JANBUS DIMENSIONLESS PARAMETERS ADAPTED FROM: HARVARD SOIL MECHANICS SERIES NO. 46 SHEAR STRESS PARAMETERS ' Unit Weight Y (Ibs/ft3) Cohesion c (Ibs/ftz) Angle of Internal Friction Tan ¢ /2(D 2ZD D ROTATIONAL SLOPE STABILITY ANALYSIS:` JOB NO.: DATE: CALCULATIONS Height of Section (H) Slope of Section YH 3.3 Ac$=.YC Tangy For ,lc$ - j.. ; Slope - %), Z Ncf From Janbu's Curves r Factor of Safety = Ncf .x yH = ROTATIONAL SLOPE STABILITY ANALYSIS:` JOB NO.: DATE: 6 0 0 GEOTECHNICAL ENGINEERING INVESTIGATION Remodel and Addition to Single Family Residence 27 Catania, Newport Coast Newport Beach, California Prepared For: Mohammad Namazian 8 Venezia PLAN REVIEL Newport Coast, California 92657 ThOwPIMA have been revianed and are raw to be in substantial comport o Beach. �'aPP3'able grading bMes adopted by City of P "Pm approval by �1� is+neommendod for permit issuance .� Pormittee akan onaPt� ll City departmentsmio and agencies; ns and construction conducted hereunder sll 5Lnll'coRM mp y in all reapacts to the Applicable codes and Ordinances and by'commeacing eOrsiruction therzunfrom and as 490w to release and indemnify Citj, uud it§ ronsuh;ants The ��gainstany code violations in the comploted Work ce or greeting of a permit based on apraoval of these ,.Pbm shall not allow or approve any violation of the applice,* codes or ordimmoo . No permit Presumed to give authority to violate or cancel the provisions of such codes or ordinances shall be valid. -HAGAHI EN/��G�INEERING INC / T . / � 2 // Project Number 17182-13 December 31, 2013 Q J `F',o,6-. / /~taw!/. LAf ?'7/T '[ 'iP1 sc- Sample No. Semple7YM Soil Description: Normal Stress Peak Stress Displacament Residual Stress Displaeemmt In Sim Dry Density in Situ Water Cantent Saturated Water Content Strain Rale 4000 3500 3000 y 2500 a v 2000 t_ t6 Of y 1500 MO 500 0 0 500 1000 1500 2000 2500 3000 3500 4000 Normal Stress (psfl NorCal Engineering DIRECT SHEAR TEST SOILS AND GEOTECHNICAL CONSULTANTS ASTM D3080 C.S. Home Design Plate A .OJECTMIMBBR: 17182-13 DATE: 12127/2013 BI@T OmlisnobedlSaWmted Silty Clay w/ Some Bedrock Fmgmeals 1 2 3 (psi) 1000 2000 3000 (psi) 912 1788 2412 (in) 0.100 0.250 0.100 (psi) 744 1788 2160 (in.) 0.250 0.250 0.250 (pct) 110.5 110.5 110.5 (%) 14.3 14.3 14.3 (%) 19.0 19.0 19.0 (inlmin) 0.020 0.020 0.020 t Oa 20 0.0 SO am 1" 120 a6c�atram(r4 YAM 19 ,, 1M■ME Oa 20 0.0 SO am 1" 120 a6c�atram(r4 RMCCAR-rv-1Y CC)NSULTING, INC January 10 2p19 Mr. Ron Hsiu WYss Group 196 Technology Drive, Suite J Irvine, California 92618 Subject; Geotechni Limited G cal Recommendations 18 Catania�t�hnical Investigation for Spa Newport Coast, California 2676 - 2or8 &JILANool &CW FEB 272019 W. g,RQ File No: 8299-00 Report No: 20190110-1 Plan Check NO.: 2676-2018 References: 18 ��n aY Consulting, Inc., Tract 15705 2018, Geotechnical Invest- Report No: 20181126 2 � Lot 33, Newp°� Coast 9ation, Proposed S Dear December 11• California,'File No: Pa, Mr. Hsiu: 8299-00, Submitted herein is a cross section and reco recommendations attached. Provided in our referen m 201 mendations to su ced December 11 mmarize the slope setback 8 report, The cross section is The planned spa structure constructed foundation elements equal to H as necessarynear the top of slope should implement bolt 73, Ora minimum horizontaldistsetbacks fr m of the foundation to°m the bottom deepened section). Slope the face of�heance feet This ttOm of the footings at least The of 15 one foot of pe has a gradient face pe along a horizodistance is measured from located depth provides an additional 2r f tmatel plane the approximatelyeel of horizontal tz ntakVThe alsee attached cro ss Slope wall. We Feet from the to ), therefore each provide a slope setback of at least 15 eel b d tion slope and 3. Planned s based on our investigation that creep depth of 5. 5 fat from the existing is to be the s as on 5 feet for the spa, which Will of Pa when constructed to the reco I°adin the information mmended a not need to be co id ded it is our Opinion Summm pth and setback. ed in the design of The recommendations of specifically superseded the referenced re acceptedIce herein. This review ports' including limitations re expressed or implied, m the engineerin has been conductedmain as stated unless report, or implied, is made as t t he coohclus oIc n sand ngineering fieldaccorallo furWith thergenerally Professional advice included nathis� 23 Corporate 2539 Suite 150, Newport Beach, Phone 949 629 I Email info(o'rm¢Ycon arth CA 92660 sulting,eOm January 10, 2019 File No: 8299-00 Report No: 20190110-1 Page No: 2 Thank you for this opportunity to be of service. If you have any questions, please contact this office. Respectfully submitted, R MCCARTHY CONSULTING, INC. Robert J. Mc 'drt'h Principal Engineer, G.E. 2490 Registration Expires 3-31-20 Date Signed: 01/10/19 R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 I Z �z Q J n r, ] 0 o U �Z N a 0 y O i m Y m E .X H W C E a 1 oc �5Inl�mo � E � N Y e wo E V m Ali ` t Ln N E. m y CL �i Ln N cmt 1 O IE o Q u u N O Ln u o a m mum o `�4o-a t z w m z z � R MCCARTHY CONSULTING, INC December 11, 2018 Wyss Group 196 Technology Drive, Suite I Irvine, California 92618 Subject: Response to 15t City Review Limited Geotechnical Investigation for Spa 18 Catania Newport Coast, California Plan Check No.: 2676-2018 File No: 8299-00 Report No: 20181211-1 References: City of Newport Beach, Community Development Department, Building Division, 2018, "Over The Counter Geotechnical Report Review Checklist, New Pool and Spa," November 14. Dear Wyss Group: Submitted herein is our response to a review by the City of Newport Beach in their First Review dated November 14, 2018. The comments in the City review are addressed below. RESPONSE TO CITY REVIEW Item 1: "The property is located in a zone identified by the State as being in a Seismic Hazard Zone. Please provide Geotechnical Investigation and recommendations in accordance with 2018 CBC code. q Response: The requested report and recommendations are attached. Item 2: 'Please review the landscape Plans & report for compliance with geotechnical recommendations of this report." Response: Plans and drawings should be forwarded to our office for review as they are revised and updated. Summary The recommendations of the referenced reports, including limitations, remain as stated unless specifically superseded herein. This review has been conducted in accordance with generally accepted practice in the engineering geologic and soils engineering field. No further warranty, 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 Phone 949 629 2539 1 Email info@rmccarthyconsulting.com December 11, 2018 File No: 8299-00 Report No: 20181211-1 Page No: 2 expressed or implied, is made as to the conclusions and professional advice included in this report. Thank you for this opportunity to be of service. If you have any questions, please contact this office. Respectfully submitted, R MCCARTHY CONSULTING, INC. Robert J. Mc art' y Principal Engineer, G.E. 2490 Registration Expires 3-31-20 Date Signed: 12/11/18 R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 R MCCARTHY CONSULTING, INC December 11, 2018 Ron Hsiu File No: 8299-00 Wyss Group Report No: 20181126-2 196 Technology Drive, Suite J Irvine, California 92618 Subject: Geotechnical Investigation Proposed Spa 18 Catania Tract 15705, Lot 33 Newport Coast, California APN: 478-162-20 INTRODUCTION This report presents the results of our geotechnical investigation for 18 Catania in the Los Trancos neighborhood of Newport Coast, within the City of Newport Beach, California. The investigation was performed to determine various site and regional geotechnical conditions pertinent to the construction of a spa currently proposed for the subject property. Analyses for this investigation are based upon a brief description of the project and conceptual plans prepared by the LCW Group. The purpose of our review and investigation was to evaluate the subsurface conditions, determine the compatibility of the proposed construction with respect to the geotechnical features of the site, and provide preliminary geotechnical recommendations and design parameters for site excavation and planned improvements. Specific information and recommendations for site development are provided herein. Project Authorization The work performed was per your authorization based on our Proposal No: 20181116-1, dated November 16, 2018. Executive Summary Based on our findings, the planned spa may be constructed at the site in the location shown on the plan provided that the spa shell foundation depth provides a minimum setback from the slope. We recommend a minimum depth of 5.5 feet, which will provide a slope setback of at least 15 feet based on the information provided. The slope at the site is a manufactured slope with a constructed intermediate terrace drain and the landslide hazard indicated on the city R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 1 (949) 629-2539 December 11, 2018 File No: 8299-00 Report No: 20181126-2 Page No: 2 hazard map was therefore remediated as part of previous rough grading. A summary of our findings, conclusions and recommendations is provided below. Scope of Investigation The investigation included the following: 1. Review of collected geologic, geotechnical engineering and seismological reports and maps pertinent to the subject site. A reference list is included in Appendix A. 2. Subsurface exploration consisting of two auger borings and one test pit in the vicinity of the proposed spa in the back yard. 3. Logging and sampling of the exploratory borings, including collection of soil samples for laboratory testing. The Logs of the exploration are included in Appendix B. 4. Laboratory testing of soil samples representative of subsurface conditions. The results are presented in Appendix C. 5. Geotechnical engineering analyses of collected data. 6. Preparation of this report containing our geotechnical recommendations for the design and construction of the spa in accordance with the current California Building Code (2016) and for use by your design professionals and contractors. Site Description The subject property is located on the south side of Catania east of the intersection of Coastal Canyon Drive and Catania in Newport Coast in Newport Beach, California, as shown on the Location Map, Figure 2. The property is flanked to the west and east by existing developed residential properties. The north side of the lot fronts Catania. The south side of the lot slopes downward. The lot size is indicated as under 10,000 square feet. Collected plans indicate that the lot has an approximately rectangular shape. The plan prepared by LCW Group (Reference 1) was used as a base map for our Geotechnical Plot Plan, Figure 1. The back yard slope is roughly 35 feet high. A survey plan of the slope was not provided as part of this investigation. The slope gradient is typically about 2:1 (Horizontal:Vertical) with one intermediate bench. No indication of slope damage or instability was observed at the time of our investigation. Vegetation on the slope appears to be well-maintained and consists of low - height ground cover, shrubs and trees. There is a low wall along the top of the slope and additional masonry block walls are located along the property lines of the adjacent properties to the north and south. The site presently contains a two-story house structure. Concrete walkways and patios cover much of the area around the existing house. The front and back yards are landscaped with lawn R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 File No: 8299-00 Report No: 20181126-2 Page No: 3 and planter areas as well as hardscape patios. The back yard hardscape and landscape is under renovation. Yard areas are drained with sloped hardscape and area drain inlets in the concrete and planter beds. Roof drains appear to be present. Yard drainage is directed toward Catania. Proposed Development The new construction will include a spa and water feature that will be built near the top of the back slope. New hardscape deck is shown around the spa improvements along with decorative planter and low -height retaining walls. SITE HISTORY The subject site was graded as part of the rough grading of Tract 14487 with geotechnical observation and documentation by GMU (1999-2001). The tract was subdivided and the lot became a portion of Tract 15705. The grading report for the specific site was not located as part of our review. Based on other work by GMU in the Newport Coast area, we expect that slopes at the site were manufactured as stabilization fills or fill slopes along the descending ridgeline. Additional cuts and fills were made as part of the precise grading. Fill materials at the property are documented engineered fills. GEOTECHNICAL CONDITIONS Geolooic Setting The property is situated within the northern portion of the San Joaquin Hills. Geologic maps prepared by Morton et al. (2004) indicate that the ridge in this vicinity is underlain by Los Trancos formation (Ttlt), very old paralic (Marine Terrace) deposits (Qtm), and the Bommer Member of the Topanga formation (Ttb). Earth Materials The site is underlain at the surface by previously placed, documented engineered fill. The fill materials encountered in our borings consisted of gray -brown silts with bedrock fragments to the maximum depth explored of 6 feet. The fill materials had moisture contents of about 19 to 28 percent. The fill materials were uniformly dense and contained abundant bedrock fragments. Laboratory test results indicate that the near surface fill materials have a low expansion potential (EI=20). The onsite earth materials should excavate readily with conventional moderate to heavy duty grading equipment. Most materials derived onsite will recompact to produce acceptable structural fill. Organic materials, debris and other unsuitable materials that may be present as R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 File No: 8299-00 Report No: 20181126-2 Page No: 4 part of the demolition should be hauled away and not used in the recompacted fill. Deepened foundation support may be required for the back yard construction to provide appropriate slope setbacks. GEOLOGIC HAZARDS The pre -development ridge slope that existed at the subject site is listed by the State of California as a seismic hazard zone for earthquake induced landslides on the Laguna Beach Quadrangle Official Map, April 15, 1998 (Reference 3). However, this condition was mitigated as part of the development of the present lot configuration at the site. Prior grading has created a flat building pad with a descending slope along the south boundary. Our borings would suggest that the slope is a fill slope or stabilized cut slope. The slope gradient is approximately 2:1 at an estimated height of about 35 feet. No evidence of deep failures and/or landslides was observed during our site investigation. No evidence of surficial instability was observed. The slope is within a maintained HOA area. The proposed development is not expected to modify the existing slope configurations at the property and yard drainage will be improved. Other geologic hazards at the site are primarily from shaking due to movement of nearby or distant faults during earthquake events. No active faults are mapped as crossing the site and the site is not located within an Alquist-Priolo special study zone. There is no geologic hazard due to active faulting near the site, shallow groundwater or other known conditions that would affect the site as further detailed below. Structure The underlying bedrock is not exposed at the site, but bedding structure in the area shown on collected geology maps indicate that the bedding generally dips at favorable angles of 12 to 30 degrees northwest in the vicinity (Morton et al, Reference 10). Additionally, the slope was evaluated and remediated as necessary as part of previous grading. There is no known adverse geologic bedding structure that is likely to affect stability at the site. The State of California has mapped several geologic faults trending northwest -southeast in the vicinity of the site. These faults were addressed as part of previous approved site grading. Slope Stabilitv The site is located in a designated slope stability area as shown on the City of Newport Beach Seismic Safety Element (2008) document (see Figure 3) and the State of California seismic hazard maps. The subject site has an approximate 35 foot tall, descending fill slope at the rear portion of the lot. No evidence of deep-seated gross instability was noted at the site during our site reconnaissance, literature and map review, and interpretation of aerial photographs. The descending slope on the lot did not exhibit evidence of past landsliding, pop -outs, erosion R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 File No: 8299-00 Report No: 20181126-2 Page No: 5 gullies or other evidence of mass wasting. The descending slope has a 2:1 (horizontal to vertical) or flatter gradient with an intermediate bench drain. Based upon the past performance of the existing and nearby slopes, the descending slope appears to have performed well since the site was originally constructed. Soil exposed within the upper 8 feet of the slope surface are sometimes subject to potential downhill creep. Such surficial instability or creep should not adversely affect proposed improvements providing appropriate foundation setbacks are utilized as recommended herein. No slope modifications are planned as part of the proposed construction. The planned structures that are constructed near the top of slope should be constructed with deepened foundation elements as necessary to maintain setbacks from the bottom of the footings at least equal to H/3, or a minimum of 15 feet to the slope surface. Soil Creep Forces on Slopes Soil creep is a surficial slope instability condition which is progressive in character and caused by expansion, contraction and erosion of sloping earth materials under the influence of gravity and changes in moisture. The creep process may, over time, remove downslope support for conventional shallow footings as well as other surface supported patios, walls and decks. Soil creep will typically affect only those portions of the lot on or adjacent to the slopes. Potential distress due to creep forces may be minimized with appropriate design which considers that most of the downslope movement of creep -prone materials at this site is expected to occur in the upper 8 feet of depth of sloping earth material. It is recommended that the proposed structural improvements at the site obtain bearing below potential creep prone materials. If appropriate setbacks are not provided, the planned spa built at the top of slope may experience rotations that cause the tile lines to appear uneven along the water line. As rotation progresses, it may affect the function of filtration systems and crack the spa shell. Water drain and supply lines may also be affected and break, resulting in leaks. Water leaks from spa lines or a cracked spa shell can in turn cause damage to the slope. These conditions are not acceptable. Remedial measures outlined herein should therefore be followed to reduce the potential for such damages due to slope creep. Additionally, deformations caused by soil movement due to natural processes such as soil creep, soil expansion and seismic shaking in the vicinity of the top of the slope cannot be entirely precluded, and it is the intent of the recommendations herein to minimize their perception. Other design considerations, which will minimize the perception of movement, include use of flexible surfacing materials, such as ungrouted pavers or well -jointed concrete rather than frangible materials such as tile, brick and stucco. Groundwater Perched groundwater can occur at shallow depth along geologic contacts and less permeable fill layers; however, no groundwater seepages were observed during our site visit or subsurface R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 File No: 8299-00 Report No: 20181126-2 Page No: 6 exploration at the property. Groundwater seepage is not anticipated to be a significant design or construction constraint, provided proper surface drainage and subdrainage systems are incorporated into the project. Surficial Runoff Proposed development should incorporate engineering and landscape drainage designed to transmit surface Flow away from the slopes to the street and/or storm drain system via non erosive pathways. Care should be taken to not allow water to pond or infiltrate soil adjacent to slopes and foundation elements. All planter boxes and garden walls should be drained. Secondary Seismic Hazards The south facing slope on the property covers an area that is listed by the State of California as a seismic hazard zone on the Laguna Beach Quadrangle Official Map, April 15, 1998. This places the site in a category of required investigation for earthquake -induced landslides. Slope stability analysis was done as part of previous grading in accordance with the County of Orange requirements for a minimum Factor of Safety of 1.5 with regard to global stability of the slope. Furthermore, there was no evidence of landslide occurrence observed with the present graded topography. Appropriate slope setbacks as recommended herein should be maintained per code requirements. Review of the Seismic Hazard Zones Map (CDMG, 1998) for the Laguna Beach Quadrangle indicates the site is not located within a zone of required investigation for earthquake - induced liquefaction. These findings are in keeping with the results of our study. Other secondary seismic hazards to the site include deep rupture, shallow ground cracking, lurching with lateral movement and settlement. With the absence of active faulting onsite, the potential for deep fault rupture is not present. The potential for shallow ground cracking to occur during an earthquake is a possibility at any site, but does not pose a significant hazard to site development. The potential for seismically induced lurching and settlement to occur is considered remote for the site. The potential for tsunami inundation at the site elevation is nil. Proposed development is considered feasible and safe from a geotechnical viewpoint provided the recommendations of this report are followed during design, construction, and maintenance of the subject property. Proposed development should not adversely affect adjacent properties, providing appropriate engineering design, construction methods and care are utilized during construction. 2. The primary consideration on this site is construction of the spa and appurtenant structures in close proximity to the top of the slope. The design and construction should take into account the recommendations herein that are intended to reduce potential adverse impacts related to the sloping ground conditions. 3. Our findings indicate that the subject property was developed as part of a previously mass graded residential home development. The spa area is expected to be excavated R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 File No: 8299-00 Report No: 20181126-2 Page No: 7 into previously placed documented engineered fill. Remedial grading is expected to be limited to removal and recompaction of disturbed shallow materials for slab -on -grade areas. 4. The existing slope materials at the site are considered to be prone to movements that may result from slope creep, seismic shaking, weathering and other natural processes and appropriate design for structures at the top of slope is recommended to help mitigate these conditions. 5. The engineered fill materials at the site are expected to be suitable for support of new structures; however, foundation and setback criteria apply where appropriate. 6. No evidence of slope instability was observed as part of our investigation and the perimeter slope areas appear to be performing favorably with respect to gross and surficial stability. With appropriate drainage and design, the planned improvements will not adversely affect the slopes but may be influenced near the top of the slope by creep and seismic affects. The proposed deepened foundations should be designed in consideration of the required slope setback requirements, as well as the potential natural slope forces (creep and seismic shaking) near the top of the slope. 8. The spa and deck will be constructed near the top of the back slope and should be constructed utilizing a deepened foundation to provide proper slope setbacks. Lateral forces and drainage will also need to be addressed as part of the design. 9. No active faults are known to transect the site and therefore the site is not expected to be adversely affected by surface rupturing. It will, however, be affected by ground motions from earthquakes during the design life of the residence. The potential for seismically induced liquefaction affecting the site is considered nil. The potential for seismically induced landsliding affecting the residence is considered to be very low given that the slope is a manufactured slope and the area has been previously graded to minimize such risks. 10. Groundwater is not expected to be a concern during construction. Suitable drainage elements need to be installed at retaining walls (including the spa) to mitigate possible transient seepage. 11. Adverse surface discharge onto or off the site is not anticipated provided proper civil engineering design and post -construction site grading are implemented. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 RECOMMENDATIONS Site Preoaration and Gradina 1. General File No: 8299-00 Report No: 20181126-2 Page No: 8 Site grading should be performed in accordance with the requirements of the City of Newport Beach, the recommendations of this report, and the Standard Grading Guidelines of Appendix D. All excavations should be supervised and approved in writing by a representative of this firm prior to placement of fill or construction. Remedial grading is recommended to include overexcavation and recompaction of unsuitable earth materials beneath the spa and slab -on -grade areas. 2. Demolition and Clearing Deleterious materials, including materials from the demolition, organic materials and trash, should be removed and disposed of offsite. Subsurface elements of demolished structures should be completely removed, including any abandoned utility lines. Subarade Preparation Previous mass grading removed surficial and weathered materials at the subject lot. Excavations should be made to remove any soils disturbed by demolition, undocumented utility backfill, planter fill and other residual soil materials where encountered within the planned improvement areas. Spa Excavation Excavations for the planned spa shell and foundations should be observed by the geotechnical consultant. A written memo should be provided by our office indicating approval for construction prior to placing concrete or gunite. Other agency inspections may also be required. Remedial grading is not expected to be necessary in the spa shell area due to depths of planned excavations. Slab -on -Grade Preparation Removals below the hardscape improvements such as patios, decks and sidewalks should be sufficient to remove unsuitable or disturbed on-site soil. Removal depths are expected to be on the order of 6 to 12 -inches to expose competent engineered fill on the lot. Removals should be followed by 6 -inches of scarification and recompaction. Deeper excavations may be necessary to remove unsuitable materials, if encountered. Excavations should be replaced with compacted engineered fill. The horizontal limits of overexcavation should be to 1 foot beyond the improvement limits (except adjacent to pre-existing slabs and footings) or as outlined by the geotechnical engineer based on grading and foundation plans when these are available for review. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 File No: 8299-00 Report No: 20181126-2 Page No: 9 The depths of overexcavation should be reviewed by the geotechnical engineer or geologist during the actual construction. Any surface or subsurface obstructions, or questionable material encountered during grading, should be brought immediately to the attention of the geotechnical engineer for recommendations. 4. Fill Soils The onsite soils are anticipated to be suitable for use as compacted fill. Fill soils should be free of debris, organic matter, cobbles and concrete fragments greater than 6 -inches in diameter. The presence of oversize rock is possible within excavations. Soils imported to the site for use as fill below foundation and slab areas should be predominantly granular, non -expansive, non -plastic and approved by the geotechnical engineer prior to importing. 5. Shrinkage Shrinkage losses are expected to be negligible overall. This does not include clearing losses from demolition that could result in volume reductions for available fill soils. 6. Expansive Soils Expansion tests should be performed during grading to determine the expansion potential of the subgrade materials. On-site soils encountered during our investigation were determined to have a low expansion potential (EI=20; See Appendix Q. 7. Comoaction Standard The onsite soils are anticipated to be suitable for use as compacted fill. Fill materials should be placed at near optimum moisture content and compacted under the observation and testing of the soil engineer. The recommended minimum density for compacted material is 90 percent of the maximum dry density as determined by ASTM D 1557-12. Field density tests should be performed per the Standard Grading Guidelines (Appendix D) and in accordance with agency requirements at the time of grading. 8. Temporary Construction Slooes Temporary slopes exposing on-site materials should be cut in accordance with Cal/OSHA Regulations. It is anticipated that the exposed on-site earth materials may be classified as Type B soil, and temporary cuts of 1:1 (horizontal:vertical) above a 4 -foot -high single bench is expected be appropriate for typical spa cuts and residential lot trench depths. Along property lines, cuts of 1:1 or flatter are typically prudent and are required by the City of Newport Beach. The material exposed in temporary excavations should be evaluated by the Contractor and Geotechnical Consultant during excavation and construction. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 File No: 8299-00 Report No: 20181126-2 Page No: 10 Flatter embankments could be required if seepage zones or dry sand layers are encountered within excavations; however, these conditions were not observed in our exploratory borings. Excavations should proceed in a manner so as not to remove lateral or bearing support of adjacent properties or structures. The soils exposed in the excavation cuts should be observed by the Geotechnical Consultant during excavation. The safety and stability of temporary construction slopes and cuts is deferred to the General Contractor, who should implement the safety practices as defined in Section 1541, Subchapter 4, of Cal/OSHA T8 Regulations (2006). The Geotechnical Consultant makes no warranties as to the stability of temporary cuts. Soil conditions may vary locally and the Contractor(s) should be prepared to remedy local instability if necessary. Contract Documents should be written in a manner that places the Contractor in the position of responsibility for the stability of all temporary excavations. Stability of excavations is also time dependent. Cuts should not be allowed to dry out and should not be left open for extended time periods. Design of Footings The spa should be constructed with a foundation that meets slope setback criteria per code and per the recommendations provided herein. Deepened footings will be required in order to provide setback distances for the foundation. Foundations may be embedded into on-site competent, undisturbed compacted fill. Footing design in the creep zone near the top of slope should recognize that soil creep movement will remove downslope support. Footings for the spa and walls adjacent to the rear slope should be designed to resist an additional lateral pressure loading of 100 pounds per cubic foot equivalent fluid pressure to the base of the creep zone. Passive resistance may be taken only below the potential creep zone. The creep zone may be assumed to include the outer 8 feet of the slope. Two No. 5 bars should be placed at the top and bottom of continuous footings in order to resist potential movement due to various factors such as subsurface imperfections and seismic shaking. A descending manufactured fill slope with a maximum height of about 35 feet is located along the southwest side of the site. A minimum horizontal foundation slope setback of 15 feet is recommended for structures and significant improvements. Planned future development that includes structural elements within 15 feet of the top of slope, measured from the top of slope toward the house, should be designed in consideration of this setback. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 Structural Design of Retaining Walls Lateral Loads File No: 8299-00 Report No: 20181126-2 Page No: 11 Active pressure forces acting on backfilled retaining walls which support level ground may be computed based on an equivalent fluid pressure of 45 pounds per cubic foot. Restrained retaining walls should be designed for 60 pounds per cubic foot for at -rest loading. The slope side of the spa should be supported in a manner that will effectively carry the spa and deck in the event of slope movement or erosion that results in a loss of lateral support. This will be somewhat dependent on the spa configuration. The slope setback criteria above should be incorporated into the design of the spa and improvements along the top of the slope. Creep forces indicated above should be added to these values where appropriate. Other topographic and structural surcharges should be addressed by the structural engineer. Minor wall rotations are possible as active earth pressures are developed and should be anticipated and considered in design of walls and adjacent hardscape. 2. Earthauake Loads on Retaining Walls The structural engineer should determine if there are retaining walls at the site within their purview that will be subject to design lateral loads due to earthquake events. Section 1803.5.12 of the 2016 CBC states that the geotechnical investigation shall include the determination of dynamic seismic lateral earth pressures on foundation walls and retaining walls supporting more than 6 feet (1.83 m) of backfill height due to design earthquake ground motions. Planned wall heights are not known by us at this time. 3. Foundation Bearing Values for Walls Footings for retaining walls may be designed for 1500 psf and should be embedded in compacted fill at a minimum depth of 24 -inches below the lowest adjacent grade and per the slope setback guidelines provided herein. 4. Wall Backfill The on-site soils are suitable for use as retaining wall backfill. Imported backfill, if needed, should consist of select, non -expansive soil or gravel. Gravel may consist of pea gravel or crushed rock. Where space for compaction equipment is adequate, on-site or imported granular, non -expansive sand materials may be compacted into place in thin lifts per the compaction requirements provided herein. Imported pea gravel or crushed rock should be placed in lifts and tamped or vibrated into place. The lift thickness for gravel is dependent on the type of material and method of compaction. Gravel lifts of 18 to 24 inches or less are recommended. The geotechnical engineer should observe the backfill placement of soil or gravel behind each wall following approval of wall R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 File No: 8299-00 Report No: 20181126-2 Page No: 12 backdrains. Gravel wall backfill material should be separated from on-site soil materials with a suitable filter fabric such as Mirafi 140N and capped with on-site soil or concrete. 5. Subdrains An approved exterior foundation subdrain system should be used to achieve control of seepage forces behind retaining walls. The details of such subdrain systems are deferred to the wall designer, builder or waterproofing consultant. The subdrain is not a substitute for waterproofing. Water in subdrain systems should be collected and delivered to suitable disposal locations or facilities. Additional recommendations may be provided when plans are available. 6. Dampproofing and Waterproofing Waterproofing should be installed in accordance with the architects' specifications or those of a waterproofing consultant. The criteria in Section 1805 of the 2016 CBC should be followed as a minimum. Hardscape Design and Construction Hardscape improvements that are outside of the creep zone may utilize conventional foundations in compacted fill. Such improvements should be designed in accordance with the foundation recommendations presented above, at a minimum bearing depth of 18 -inches. Cracking and offsets at joints are possible; however occurrence may be minimized by appropriate drainage and the use of thickened edge beams to limit moisture transfer below slabs. Hardscape improvements within the slope setback and creep zone should be provided with deepened foundation support. Concrete flatwork should be divided into as nearly square panels as possible. Joints should be provided at maximum 6 feet intervals to give articulation to the concrete panels (shorter spacing is recommended if needed to square the panels). Landscaping and planters adjacent to concrete flatwork should be designed in such a manner as to direct drainage away from concrete areas to approved outlets. Planters located adjacent to principle foundation elements or slopes should be sealed and drained; this is especially important if they are near retaining wall backfills. Flatwork elements should be a minimum 5 inches thick (actual) and reinforced with No. 4 bars 18 inches on center both ways. Subgrade soils should be well moistened prior to placement of concrete. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 Surface and Subsurface Drainage 1. Finished Grade and Surface Drainage File No: 8299-00 Report No: 20181126-2 Page No: 13 Finished grades should be designed and constructed so that no water ponds in the vicinity of foundations or slopes. Drainage design in accordance with the 2016 CBC, Section 1804.4, is recommended or per local City requirements. Roof gutters should be provided and outflow directed away from the house in a non-erosive manner as specified by the Project Civil Engineer or Landscape Architect. Proper interception and disposal of on-site surface discharge is presumed to be a matter of civil engineering or landscape architectural design. Additional drainage information is provided in Appendix E, Suggested Guidelines for Maintenance of Hillside Property. 2. Drainage and Drainage Devices The performance of the planned foundation and improvements is dependent upon maintaining adequate surface drainage both during and after construction. The ground surface around foundations, slopes and improvements should be graded so that surface water will not collect and pond. The impact of heavy irrigation can artificially create perched water conditions. This may result in seepage or shallow groundwater conditions where previously none existed. Attention to surface drainage and controlled irrigation will significantly reduce the potential for future problems related to water infiltration. Irrigation should be well controlled and minimized. Seasonal adjustments should be made to prevent excessive watering. Sources of uncontrolled water, such as leaky water pipes or drains, should be repaired if identified. The Owner should be aware of the potential problems that could develop when drainage is altered through construction of retaining walls, paved walkways, utility installations or other various improvements. Ponded water, incorrect drainage, leaky irrigation systems, overwatering or other conditions that could lead to unwanted groundwater infiltration must be avoided. Area drains should be installed in all planter and landscape areas. Planter surfaces should be sloped away from building and slope areas in accordance with Code requirements. Roof drainage should be tight -lined into the area drain system or carried to outlets away from building foundations. Planters should not be allowed adjacent to foundations unless they are lined with a bottom barrier installed with a minimum 5 percent gradient away from foundations. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 File No: 8299-00 Report No: 20181126-2 Page No: 14 Irrigation water should be controlled for the landscape areas in a way that maintains uniform moisture conditions around and below the building slab and footings. Changes in exterior moisture will promote heave and desiccation in the soil supporting foundations and must, therefore, be avoided. Installation of concrete patios and walkways adjacent to the building is recommended as preferable to planters. 3. Infiltration On-site surface soils have a low to moderate permeability. It is recommended that surface water be collected and directed to a suitable off-site outlet rather than allowed to infiltrate into the soil; however, some types of trench drain infiltration may be allowed for low flow volumes. Such devices should not be sited near slopes or foundations. Surface and subsurface drainage should be directed toward approved outlets. Concrete Construction Components in Contact with Soil Consultant reports for the previous grading in the vicinity indicate that some fill soils have the potential for severe corrosion of concrete due to high soluble sulfate content. Type V cement may be utilized for concrete in contact with the on-site soils. It is recommended that a concrete expert be retained to design an appropriate concrete mix to address the structural requirements. In lieu of retaining a concrete expert, it is recommended that the 2016 California Building Code, Section 1904 and 1905 be utilized, which refers to ACI 318. Metal Construction Components in Contact with Soil Metal rebar encased in concrete, iron pipes, copper pipes, lift shafts, air conditioner units, etc. that are in contact with soil or water that permeates the soil should be protected from corrosion that may result from salts contained in the soil. Recommendations to mitigate damage due to corrosive soils, if needed, should be provided by a qualified corrosion specialist. Foundation Plan Review The undersigned should review final foundation plans and specifications (including the spa plans) prior to their submission to the building official for issuance of permits. The review is to be performed only for the limited purpose of checking for conformance with design concepts and the information provided herein. Review shall not include evaluation of the accuracy or completeness of details, such as quantities, dimensions, weights or gauges, fabrication processes, construction means or methods, coordination of the work with other trades or construction safety precautions, all of which are the sole responsibility of the Contractor. R McCarthy Consulting's review shall be conducted with reasonable promptness while allowing sufficient time in our judgment to permit adequate review. Review of a specific item shall not indicate that R McCarthy Consulting has reviewed the entire system of which the item is a component. R McCarthy Consulting shall not be responsible for any deviation from the Construction Documents not brought to our attention in writing by the Contractor. R McCarthy Consulting shall not be required to review partial submissions or those for which submissions of correlated items have not been received. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 Utility Trench Backfill File No: 8299-00 Report No: 20181126-2 Page No: 15 Utility trench backfill should be placed in accordance with Appendix D, Standard Earthwork Guidelines. It is the owner's and contractor's responsibility to inform subcontractors of these requirements and to notify R McCarthy Consulting when backfill placement is to begin. It has been our experience that trench backfill requirements are rigorously enforced by the City of Newport Beach. Observation and Testing Geotechnical observation and testing during construction is required to verify proper removal of unsuitable materials, check that foundation excavations are clean and founded in competent material, to test for proper moisture content and proper degree of compaction of fill, to test and observe placement of wall and trench backfill materials, and to confirm design assumptions. It is noted that the CBC requires continuous verification and testing during placement of fill, pile driving, and pier/pile drilling. An R McCarthy Consulting, Inc. representative shall observe the site at intervals appropriate to the phase of construction, as notified by the Contractor, in order to observe the work completed by the Contractor. Such visits and observation are not intended to be an exhaustive check or a detailed inspection of the Contractor's work but rather are to allow R McCarthy Consulting, Inc., as an experienced professional, to become generally familiar with the work in progress and to determine, in general, if the grading and construction is in accordance with the recommendations of this report. R McCarthy Consulting, Inc. shall not supervise, direct, or control the Contractor's work. R McCarthy Consulting, Inc. shall have no responsibility for the construction means, methods, techniques, sequences, or procedures selected by the Contractor, the Contractor's safety precautions or programs in connection with the work. These rights and responsibilities are solely those of the Contractor. R McCarthy Consulting, Inc. shall not be responsible for any acts or omission of any entity performing any portion of the work, including the Contractor, subcontractor, or any agents or employees of any of them. R McCarthy Consulting, Inc. does not guarantee the performance of any other parties on the project site, including the Contractor, and shall not be responsible for the Contractor's failure to perform its work in accordance with the Contractor documents or any applicable law, codes, rules or regulations. Construction phase observations are beyond the scope of this investigation and budget and are conducted on a time and material basis. The responsibility for timely notification of the start of construction and ongoing geotechnically involved phases of construction is that of the Owner and Contractor. We request at least 48 hours' notice when such services are required. List of Guidelines The geotechnical consultant should be notified to observe and test the following activities during grading and construction: R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 File No: 8299-00 Report No: 20181126-2 Page No: 16 • To observe proper removal of unsuitable materials; • to observe the bottom of removals for all excavations for the pad grading, trenching, exterior site improvements, etc. • to observe side cut excavations for retaining walls, trenches, etc.; • to test for proper moisture content and proper degree of compaction of fill; • to check that foundation excavations are clean and founded in competent material; • prior to and after pre-soaking of the slab subgrade soils (if necessary); • to check the slab subgrade materials prior to placing the sand, gravel, and/or concrete; • to check retaining wall subdrain installation when the pipe is exposed and before it is covered by the gravel and fabric; and again after the gravel and fabric have been placed; • to test and observe placement of wall backfill materials; • to test and observe placement of trench backfill materials; • to test and observe patio, spa deck and sidewalk subgrade materials; • to observe any other fills or backfills that may be constructed at the site. It is noted that this list should be used as a guideline. Additional observations and testing may be required per local agency and code requirements at the time of the actual construction. The 2016 CBC requires continuous verification and testing during placement of fill materials and during pile/caisson drilling. This investigation has been conducted in accordance with generally accepted practice in the engineering geologic and soils engineering field. No further warranty, expressed or implied, is made as to the conclusions and professional advice included in this report. Conclusions and recommendations presented are based on subsurface conditions encountered and are not meant to imply that we have control over the natural site conditions. The samples taken and used for testing, the observations made and the field testing performed are believed representative of the general project area; however, soil and geologic conditions can vary significantly between tested or observed locations. Site geotechnical conditions may change with time due to natural processes or the works of man on this or adjacent properties. In addition, changes in applicable or appropriate standards may occur as a result of the broadening of knowledge, new legislation, or agency requirements. The recommendations presented herein are therefore arbitrarily set as valid for one year from the report date. The recommendations are also specific to the current proposed development. Changes in proposed land use or development may require supplemental investigation or recommendations. Also, independent use of this report without appropriate geotechnical consultation is not approved or recommended. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 December 11, 2018 File No: 8299-00 Report No: 20181126-2 Page No: 17 Thank you for this opportunity to be of service. If you have any questions, please contact this office. Respectfully submitted, R MCCARTHY CONSULTING, INC. Robert J. McCarthy Principal Engineer, G.E.2490 Registration Expires 3-31-20 Date Signed: 12/11/18 Distribution: (1) Addressee Accomoanvino Illustrations and Anoendices Figure 1 - Geotechnical Plot Plan Figure 2 - Location Map Figure 3 - Landslide Hazard Map Appendix A - References Appendix B - Field Exploration Figures B-1 through B-4 Appendix C - Laboratory Testing Appendix D - Standard Earthwork Guideline Appendix E - Suggested Guidelines for Maintenance of Hillside Property R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150 Newport Beach, CA 92660 M1 t Ary4e+ 7-7 I i PA i T- J J4, 1 t C �PA .rep i. jmnz PA PA 3 19 PA x w a i8 A P.2 • � PA t H SA 3 r � i r Pa GAi 'AA2 w Sas l PA PA HA -2 A ti'B M PA Pmt p TP -1 w PAI tl N PA R PA -x 'vp xA W a Pd 3 A EXPLANATION HA -2-0 Estimated Location of Hand Auger Boring TP -1 $ Estimated Location of Test Pit 0 20 40 Figure 1 - Geotechnical Plot Plan SCALE, FEET 18 Catania Base map source: Construction Plan, Details by LCW Group Newport Coast, CA R MCCARTHY Landscape Architecture, dated 6/25/18. File: 8299-00 December 2018 = CONSULTING. INC I O O ck m N 00 Q z J LLL N U'O N @ a YL N \ N @ O @ O m NZ @ @ > m o Evow @ n �t N O LLL O 10 VOJ .. ®mm 1 m p Q H Cb gFACM y. i \ O O ck m N 00 Q z J LLL ? •' n ''7 rk R It Q. !} " n ? 0. r' n ry ? n n ? ? r � h f} n r} ry rIJ n ryi. rt nl r} n d r> m c m m a r? "r) rr h n n '? n n '`? n? ^ n 'r) r} m n �^ ry ry nn r? ry r? n r} r} r} R ,} n ryr} r} ry ,} r} w ¢� nr} nAn 1 rJ'n nl r ,S n ol'T Rr}•,\nf}h n� (M1 R. '6n M f} YO pN " P A ry !} " n r}. 7" Z N E`6 �C'= n r n nn « nrn m m c -ba rJ R n `} o r r n'� .r } `7 R �} « n R q •'} ° n mom d n1J6 R ry !} ata r} NVQ `', n nr.} n• n t j ,7 h `..�-.. rF n h ry R R ry m ` n O Cr Rn. iy'yn ,) n +? ,7n n 0r} r}., �Wa aEi E - r?, r o �7 r; r ^ .. r} n r,,'' '7 .nn n n n nryn n' n �F.7n n =ry\ nrn n n«rTn nr n ^ n n r; ° -. r} n •.7 -rye rr r} ry q O cq .ry nn -7 rn ^• ri T r. n �7 V r}ten ry r} r. n r} o f-y.•.� ',? n rt n n rj " s Y 'v' '> r} rJ rr r « O n n l -�r} r) « r ) !} ,-• n n �, f wry', fr R•Jf, r} n ry rr « rJ .S} r} n'M1 0. n n O « n r) r ? ?to r Iti F o n r r} n« r} � ,r r} n n } 'h " « N • R r • n n r n 1.O _ n •r ryn ^ ,,y ♦,. �n,ry rj n s n "ri^'" r "r}n nryVVn440 nr}, o Rn nr}!r} Or;aT "r, rt rr r) ^ b'J " R ? « O try n�4 Y. r r} I, bjp -} n .. ^ r} r} Rr} « ,,. ?.. ry r} r r-. rj b0J x n s ^ r n n Y Q n ri} n ,> rr R rJ R r R r} ♦ ry r} r} ~ h!1 nrJ Rr � ' nrT n Q. Tr}'. ¢ «RrZ�,h « rnr?" n ^ Y ''.'r. 'r. '' r^ r, "r} my S r• rs r} r>tr} nr) h ri «r} r, >n p rJ r,��'r, !t nr} n. ^rj r} o r. m n° n 0. r,. n R r} r) n ' n O ry «. r}�S1 «:�, 'n n rl' nrl P r} !Y z n ry r} o n ry ° n �} r° - « n rr fl Q n- n 2 n n ?n} Fr r}«r}« �D ... R ri. ° r -j,..._ �J n n M1 � rr n ry...'Y�-, n n .''1 n •. n r. 'li lT r o 0 « 0 n r}- r} O .--i O N LU W O] uj W U W ❑ 0 O 01 O� N 00 Z W J LLL APPENDIX A REFERENCES R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 APPENDIX A (18 Catania, Newport Coast) 1. LCW Group, 2018, "Chen Residence, Landscape Construction Plan, 18 Catania, Newport Coast, CA, 92657," Sheet LC -1.01, June 25. 2. California Building Code, 2016 Edition. 3. California Division of Mines and Geology, 2001, "Seismic Hazards Zones Map, Tustin Quadrangle," January 17. 4. California Divisions of Mines and Geology, 2008, "Guidelines for Evaluating and Mitigating Seismic Hazards in California," Special Publication 117A. 5. Department of the Navy, 1982, NAVFAC DM -7.1, Soil Mechanics, Design Manual 7.1, Naval Facilities Engineering Command. 6. Goffman, McCormick & Urban, Inc., 1999, "Retaining Wall Excavation, Wall 'C', Lots 37 through 42, Tract 15705, Newport Coast," Project 98-44, Permit No. GB980156, Site Address: 20868 Vista Ridge Road, February 22. 7. Goffman, McCormick & Urban, Inc., 2000, "Report of Geotechnical Observation and Testing of Precise Grading and Utility Trench and Retaining Wall Backfill, Lots 23 through 31, Tract 15705, Newport Coast, California, prepared for Shea Homes," Project 98-44, Precise Grading Permit: GB980153, Project Address: 20878 Vista Ridge Road, January 7. 8. Goffman, McCormick & Urban, Inc., 2001, "Report of Geotechnical Observation and Testing of Precise Grading and Utility Trench and Retaining Wall Backfill, Lots 32, and 36 through 42, Tract 15705, Newport Coast, California, prepared for Shea Homes," Project 98-44, Precise Grading Permit: GB980133 (Models), GB980153 (Production), Project Address: 20878 Vista Ridge Road, March 30. 9. Morton and Miller, 1981, Geologic Map of Orange County, CDMG Bulletin 204. 10. Morton, D. M., Bovard, Kelly H., and Alvarez, Rachel M., 2004, Preliminary Digital Geological Map of the 30'X 60' Santa Ana Quadrangle, Southern California, Version 2.0, Open -File Report 99-172, Version 2.0 — 2004. 11. Morton, P. K., Miller, R. V., and Evans, J. R., 1976, Environmental Geology of Orange County, California: California Division of Mines and Geology, Open File Report 79-8 LA. 12. Morton, Douglas M., and Miller, Fred K., compilers, 2006, "Geologic Map of the San Bernardino and Santa Ana 30'X 60' Quadrangles, California," U. S. Geological Survey Open File Report 2006-1217. 13. NorCal Engineering, 2013, "Geotechnical Engineering Investigation, Remodel and Addition to Single Family Residence, 27 Catania, Newport Coast, Newport Beach, California, prepared for Mohammed Namazian, 8 Venezia, Newport Coast, California 92657," Project Number 17182-13, December 31. 14. Tan, Siang, S., and Edgington, William J., 1976, "Geology and Engineering Geology of the Laguna Beach Quadrangle, Orange County, California," California Division of Mines and Geology, Special Report 127. 15. Vedder, J. G., Yerkes, R. F., and Schoellhamer, J. E., 1957, Geologic Map of the San Joaquin Hills - San Juan Capistrano Area, Orange County, California, U. S. Geological Survey, Oil and Gas Investigations Map OM -193. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 APPENDIX B FIELD EXPLORATION R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 APPENDIX B FIELD EXPLORATION PROGRAM (18 Catania, Newport Coast) General Subsurface conditions were explored by excavating 2 hand -auger borings and one test pit on November 21, 2018. The excavations extended to depths ranging from about 3.5 feet to 6 feet below grade and all were terminated due to refusal on rocks and/or rock fragments. The estimated locations of the borings are shown on the Geotechnical Plot Plan, Figure 1. A Key to Logs is included as Figure B-1. Boring and Test Pit Logs are included as Figures B-2 through B- 4. Excavation of the borings was observed by our field engineer who logged the soils and obtained samples for identification and laboratory testing. Exploratory excavations were located in the field by pacing from known landmarks. Their locations as shown are, therefore, within the accuracy of such measurements. Sample Program 1. Hand Augers - Relatively undisturbed drive samples were obtained by utilizing a sampler lined on the inside with brass rings, each 1 -inch long and 2.5 -inches outside diameter. The sample is typically driven for a total length of about 8 -inches. The number of blows per inches of driving are recorded on the boring logs. The slide hammer used to drive the samples has a weight of 10.3 pounds with effort. The slide hammer drop height was 18 -inches. The hammer weight alone was not sufficient to drive the sample; additional energy was applied by the drilling operator by thrust force on the hammer from the topmost position. The brass rings were removed from the sampler and transferred into a plastic tube and sealed. 2. Bulk samples representative of subsurface conditions were collected from the excavations, sealed in plastic bags and transported to our laboratory. Summary The soils were classified based on field observations and laboratory tests. The classification is in accordance with ASTM D2487 (the Unified Soil Classification System). Collected samples were transported to the laboratory for testing. Groundwater was not encountered. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 UNIFIED SOIL CLASSIFICATION CHART MAJOR DIVISIONS GROUP svMeoL SYMBOLS TYPICAL NAMES o . '. . Well graded gravels and gravel -sand mixtures, little or GRAVELS: CLEAN ,' GW - '.o• no fines n Poorly graded gravels and gravel -sand mixtures, little 500% or more of GRAVELSGP coarse fraction or no fines COARSE-GRAINED SOILS: retained GRAVEL GM silty gravels, gravel -sand -silt mixtures WITH more than 50% retained on on No. 4 sieve FINES GC " Clayey gravels, gravel -sand -clay mixtures No. 200 sieve (based on the SW well graded sands and gravelly sand, little or no fines material passing the 3 -inch SANDS: CLEAN SANDS - Poorly graded sands and gravelly sands, little or no [75mm] sieve) more than 50% of SPfines SANDS SMSilty 1' sands, sand -silt mixtures coarse fraction passes No. 4 sieve WIni FINES SG Clayey sands, sand -clay mixtures Inorganic silts, very fine sands, rock Flour, sil y or ML clayey fine sands SILTS AND CLAYS: Inorganic clays of low to medium plasticity, gravelly Liquid Limit 50% or less GL clays, sandy clays, silty clays, lean clays FINE-GRAINED SOILS: OL ' Organic silts and organic silty clays of low plasticity 50% or more passes Inorganic silts, micaceous or diatomaceous fine sands No. 200 sieve* SILTS AND CLAYS: MH or silts, elastic clays CH Inorganic clays of high plasticity, fat clays Liquid Limit greater OH Organic clays of medium to high plasticity than 50% HIGHLY ORGANIC SOILS PT_ — _ Peat, muck, and other highly organic soils KEY TO LOGS NOTATION SAMPLER TYPE SYMBOL C Core barrel F1Modified California Sampler (3" O.D.) CA California split -barrel sampler with 2.5 -inch outside diameter and a 1.93 -inch diameter F1inside Modified California Sampler, no recovery D&M Dames & Moore piston sampler using m Standard Penetration Test, ASTM D 1586 2.5 -inch outside diameter, thin-walled tube Standard m Penetration Test, no recovery 0 Osterberg piston sampler using 3.0 -inch outside diameter, thin-walled Shelby tube ® Thin-walled tube sample using Pitcher barrel PTB Pitcher tube sampler using 3.0 -inch outside diameter, thin-walled Shelby tube ® Thin-walled tube sample, pushed or used Osterberg S&H Sprague & Henwood split -barrel sampler with a 3.0 -inch outside diameter and a sampler ® Disaggregated (bulk) sample 2.43 -inch inside diameter 1 Water level SPT Standard Penetration Test (SPT) split -barrel sampler with a 2.0 -inch outside diameter and a 1.5 -inch inside diameter ST Shelby Tube (3.0 -inch outside diameter, thin-walled tube) advanced with hydraulic pressure Figure B -t Unified Soil Classification R MCCARTHY NR No Recovery Chart/Key To Logs -CoNsunINC SITE LOCATION: 18 Catania, Newport Coast EQUIPMENT: Hand -Auger DATE: 11/21/2018 SURFACE ELEVATION: BY: SPC Lu U z LU o BORING NO: HA -1 O n a w O w Q� Z Lr)U 2i g U) M ma z m o MATERIAL DESCRIPTION NOTES in 0 0-5': ENGINEERED FILL (Ef): gray -brown Sandy SILT 0 with abundant SILTSTONE/SANDSTONE fragments, moist, well-compacted/dense/firm 2 2 ML 50/6" 19.3 104 ML 38/6" 23.1 - @2.5' Sample disturbed 4 4 Total Depth: 5 Feet (Refusal on rock or rock fragments) No Groundwater No Caving 6 6 8 8 10 10 FILE NO: 8299-00 LOG OF BORING FIGURE B-2 R MCCARTHY CONSULTING, INC. SITE LOCATION: 18 Catania, Newport Coast EQUIPMENT: Hand-Auger DATE: 11/21/2018 SURFACE ELEVATION: BY: SPC U z a BORING NO: HA-2 D O Lna w g w Ln Z =Lng �w U U a Q U3 M rno w = o vUi m z ¢ m O o MATERIAL DESCRIPTION NOTES p 0 @0-6' ENGINEERED FILL (Ef): Gray-brown, mottled, 0 sandy SILT with bedrock fragments, moist, firm 2 2 4 4 ML 34/6" 27.5 97 6 6 Total Depth: 6 Feet (Refusal on rock or rack fragments) No Groundwater No Caving 8 8 10 10 FILE NO: 8299-00 LOG OF BORING FIGURE B-3 R MCCARTHY CONSULTING, INC. SITE LOCATION: 18 Catania, Newport Coast EQUIPMENT: Hand- Auger DATE: 11/21/2018 SURFACE ELEVATION: BY: SPC U W o TEST PIT NO: TP -1 o W W U U z W xLn a o x oLn mz m f p MATERIAL DESCRIPTION NOTES p 0 @0-3.5': ENGINEERED FILL (Ef): gray -brown, mottled, 0 Sandy SILT with bedrock fragments, moist, firm EI=20 2 2 ML 50/5" 19.1 108 Total Depth: 3.5 Feet (Refusal on rock or rock fragments 4 No Groundwater 4 No Caving 6 6 8 8 10 10 FILE NO: 8299-00 LOG OF TEST PIT FIGURE B-4 R MCCARTHY CONSULTING, INC. APPENDIX C LABORATORY TESTING R McCarthy Consulting, Inc 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 APPENDIX C LABORATORY TESTING (18 Catania, Newport Coast) The laboratory testing program was designed to fit the specific needs of this project and was limited to testing the soil samples collected during the on-site exploration. The test program was performed by our laboratory. Soils were classified visually and per the results of laboratory testing according to ASTM D 2487, the Unified Soil Classification System (USCS). The field moisture content and dry densities of the soils encountered were determined by performing laboratory tests on the collected samples. The results of the moisture tests, density determinations and soil classifications are shown on the Boring Logs, Figures B-2 through B-4. Expansion Index Test An expansion index test was performed in accordance with ASTM: D4829. The results are summarized below. RESULTS OF EXPANSION INDEX ASTM: D4829 Test Location Soil Classification Expansion Index Expansion Potential TP -1 @ 0-3' ML 20 Low Moisture Content: Before Test= 12.3% After Test = 21.5% Percent Before Test = 58% Saturation: R McCarthy Consulting, Inc 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 APPENDIX D STANDARD GRADING GUIDELINES R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 APPENDIX D STANDARD GRADING GUIDELINES These Guidelines present the usual and minimum requirements for grading operations observed by R McCarthy Consulting, Inc., (RMC), or its designated representative. No deviation from these guidelines will be allowed, except where specifically superseded in the geotechnical report signed by a registered geotechnical engineer. The placement, spreading, mixing, watering, and compaction of the fills in strict accordance with these guidelines shall be the sole responsibility of the Contractor. The construction, excavation, and placement of fill shall be under the direct observation of the Geotechnical Engineer or any person or persons employed by the licensed Geotechnical Engineer signing the soils report. If unsatisfactory soil -related conditions exist, the Geotechnical Engineer shall have the authority to reject the compacted fill ground and, if necessary, excavation equipment will be shut down to permit completion of compaction. Conformance with these specifications will be discussed in the final report issued by the Geotechnical Engineer. All brush, vegetation and other deleterious material such as rubbish shall be collected, piled and removed from the site prior to placing fill, leaving the site clear and free from objectionable material. Soil, alluvium, or rock materials determined by the Geotechnical Engineer as being unsuitable for placement in compacted fills shall be removed from the site. Any material incorporated as part of a compacted fill must be approved by the Geotechnical Engineer. The surface shall then be plowed or scarified to a minimum depth of 6 -inches until the surface is free from uneven features that would tend to prevent uniform compaction by the equipment used. After the area to receive fill has been cleared and scarified, it shall be disced or bladed by the contractor until it is uniform and free from large clods, brought to the proper moisture content and compacted to minimum requirements. If the scarified zone is greater than 12 - inches in depth, the excess shall be removed and placed in lifts restricted to 6 -inches. Any underground structures such as cesspools, cisterns, mining shafts, tunnels, septic tanks, wells, pipe lines or others not located prior to grading are to be removed or treated in a manner prescribed by the Geotechnical Engineer. W111111111411 1ll�i Materials for compacted fill shall consist of materials previously approved by the Geotechnical Engineer. Fill materials may be excavated from the cut area or imported from other approved sources, and soils from one or more sources may be blended. Fill soils shall be free from organic (vegetation) materials and other unsuitable substances. Normally, the material shall contain no rocks or hard lumps greater than 6 -inches in size and shall contain at least 50 R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 percent of material smaller than 1/4 -inch in size. Materials greater than 4 -inches in size shall be placed so that they are completely surrounded by compacted fines; no nesting of rocks shall be permitted. No material of a perishable, spongy, or otherwise of an unsuitable nature shall be used in the fill soils. Representative samples of materials to be utilized, as compacted fill shall be analyzed in the laboratory by the Geotechnical Engineer to determine their physical properties. If any material other than that previously tested is encountered during grading, the appropriate analysis of this material shall be conducted by the Geotechnical Engineer in a timely manner. PLACING. SPREADING. AND COMPACTING FILL MATERIAL Soil materials shall be uniformly and evenly processed, spread, watered, and compacted in thin lifts not to exceed 6 -inches in thickness. Achievement of a uniformly dense and uniformly moisture conditioned compacted soil layer should be the objective of the equipment operators performing the work for the Owner and Contractor. When the moisture content of the fill material is below that specified by the Geotechnical Engineer, water shall be added by the Contractor until the moisture content is near optimum as specified. Moisture levels should generally be at optimum moisture content or greater. When the moisture content of the fill material is above that specified by the Geotechnical Engineer, the fill material shall be aerated by the Contractor by blading, mixing, or other satisfactory methods until the moisture content is near the specified level. After each layer has been placed, mixed, and spread evenly, it shall be thoroughly compacted to 90 percent of the maximum laboratory density in compliance with ASTM D1557 (five layers). Compaction shall be accomplished by sheepsfoot rollers, vibratory rollers, multiple -wheel pneumatic -tired rollers, or other types of acceptable compacting equipment. Equipment shall be of such design that it will be able to compact the fill to the specified density. Compaction shall be continuous over the entire area and the equipment shall make sufficient passes to obtain the desired density uniformly. A minimum relative compaction of 90 percent out to the finished slope face of all fill slopes will be required. Compacting of the slopes shall be accomplished by backrolling the slopes in increments of 2 to 5 feet in elevation gain or by overbuilding and cutting back to the compacted inner core, or by any other procedure, which produces the required compaction. GRADING OBSERVATIONS The Geotechnical Engineer shall observe the fill placement during the course of the grading process and will prepare a written report upon completion of grading. The compaction report shall make a statement as to compliance with these guidelines. As a minimum, one density test shall be required for each 2 vertical feet of fill placed, or 1 for each 1,000 cubic yards of fill, whichever requires the greater number of tests; however, testing should not be limited based on these guidelines and more testing is generally preferable. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 Processed ground to receive fill, including removal areas such as canyon or swale cleanouts, must be observed by the Geotechnical Engineer and/or Engineering Geologist prior to fill placement. The Contractor shall notify the Geotechnical Engineer when these areas are ready for observation. UTILITY LINE BACKFILL Utility line backfill beneath and adjacent to structures; beneath pavements; adjacent and parallel to the toe of a slope; and in sloping surfaces steeper than ten horizontal to one vertical (10:1), shall be compacted and tested in accordance with the criteria given in the text of this report. Alternately, relatively self -compacting material may be used. The material specification and method of placement shall be recommended and observed by the Soil Engineer, and approved by the Geotechnical Engineer and Building Official before use and prior to backfilling. Utility line backfill in areas other than those stated above are generally subject to similar compaction standards and will require approval by the Soil Engineer. The final utility line backfill report from the Project Soil Engineer shall include an approval statement that the backfill is suitable for the intended use. PROTECTION OF WORK During the grading process and prior to the complete construction of permanent drainage controls, it shall be the responsibility of the Contractor to provide good drainage and prevent ponding of water and damage to adjoining properties or to finished work on the site. After the Geotechnical Engineer has finished observations of the completed grading, no further excavations and/or filling shall be performed without the approval of the Geotechnical Engineer. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 APPENDIX E Suggested Guidelines for Maintenance of Hillside Property Slopes and Slone Drainage Devices Maintenance of slopes and drainage devices is important to their long term performance. The following is a list of suggested procedures provided as a guide for slope maintenance. 1. Drainage Devices Associated with Hillsides • Graded berms, swales, area drains, and slopes are designed to carry surface water from pad areas and should not be blocked or destroyed. Water should not be allowed to pond in pad areas, or overtop and flow onto graded or natural slopes. • Sources of uncontrolled water, such as leaky water pipes or drains, should be repaired if identified. • Devices constructed to drain and protect slopes, including brow ditches, berms, terrace drains and down drains should be maintained regularly, and in particular, should not be allowed to clog such that water can flow unchecked over slope faces. • Subdrain outlets should be maintained to prevent burial or other blockage. 2. Slopes • Slopes in the southern California area should be planted with appropriate drought - resistant vegetation as recommended by a landscape architect. • Rodent activity should be controlled on the slope and within yard areas along the top of the slope as burrowing may introduce paths for transfer of water into the subsurface soils and out to the slope face. Lot and Building Pad Drainage Roof drains should collect water into a tight -lined drainage system of area drains. When area drain systems are not feasible, roof drain water should be diverted by swales and sloping ground to approved outlet areas. Where planters or unimproved ground are located next to building foundations or slab -on -grade construction, roof drain outlets should be extended at least 3 feet away from the structure. Outlets and infiltration of roof water next to structures is not acceptable and should be eliminated by drainage devices. 2. Area drain inlet grates should be properly installed and maintained. The inlets need to be properly located at low grade collection points within yard areas. The grate should be installed low enough to quickly transfer collecting water into the area drain system. Inlets should also be installed high enough to not be easily buried, silted over or choked out by vegetation. 3. Drainage inlet grates should be regularly inspected and cleaned/replaced as necessary to allow free flow of water into the drain system while effectively blocking larger detritus from entering risers and flow pipes. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 APPENDIX E Suggested Guidelines for Maintenance of Hillside Property 4. Area drain pipes should be periodically checked for blockage and cleaned as necessary. Landscape grades should be maintained or improved to allow efficient drainage to approved surface water outlets and into the storm drain system. Modifications to designed or existing drainage grades should be made as necessary when excess water, standing water, low flows, etc. are noticed. An experienced landscape contractor or landscape architect should be consulted if necessary to provide recommendations for drainage improvements. 6. As yard improvements are made to existing residential properties, it is common for unlicensed landscape contractors, gardeners or the homeowner to alter the flow patterns that were designed for site drainage. Such actions however can be harmful to the property. Adverse infiltration and surface flows may cause damage to foundations, slabs, concrete hardscape, slopes, neighboring properties, etc. and result in large repair costs and/or litigation. Water Use 1. Irrigation of on-site vegetation should be properly controlled. Excessive watering should be avoided not only to save water, but also to protect property. 2. Water line leaks should be repaired quickly when identified. 3. Irrigation line problems, such as broken sprinkler heads, broken pipes, leaks at joints, or other breaches should be promptly repaired when identified. R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 uJ, 1 is i /.„, > ' .'>'✓ a Yr '°de6,.� o a�5 v/ Ak / >.� ) 4r''•'\k11' /Jf ...rj,.,. -- .,4 r I pI . a.� 7/ �i s 1 '" I• � /� � y� Pfi til p' ��' 1 r ..•�`+9f�y� <. .,� 1..... �.. n., r. =SVS .��" tt � �_ _,