The URL can be used to link to this page

Home My WebLink AboutSDP 98-15; KELLY RANCH VILLAGE F; LIMITED GEOTECHNICAL EVALUATION; 2014-05-14,1 ·1 I I I LIMITED GEOTECHNICAL EVALUATION PARKING LOT EXPANSION, AGUA HEDIONDA I LAGOON FOUNDATION, I CARLSBAD, CALIFORNIA I Prepared For: I I Agua Hedionda Lagoon Foundation c/o Hofman Planning & Engineering I 3152 Lionshead Avenue Carlsbad, CA 92010 I ~ I Project No. 10693.001 ~ 0 SfJP98;p I May 14, 2014 Z ~ I (Revised July 28, 2014) 0 W I :r: 0 I z :s I Leighton Consulting, Inc. 'iI:> I A LEIGHTON GROUP COMPANY I' I I I I I I I I I I I I I I I I I I Leighton Consulting, Inc. A LEIGHTON GROUP COMPANY To: Attention: Subject: Introduction May 14, 2014 (Revised July 28,2014) Agua Hedionda Lagoon Foundation c/o Hofman Planning & Engineering 3152 Lionshead Avenue Carlsbad, CA 92010 Mr. Eduardo Cadena, PE Project No. 10693.001 Limited Geotechnical Evaluation for Parking Lot Expansion, Agua Hedionda Lagoon Foundation, Carlsbad, California In accordance with the request your, this letter presents the results of our limited geotechnical evaluation of the proposed Agua Hedionda Lagoon Foundation parking lot expansion area, located at 1580 Cannon Road in Carlsbad, California (see Figure 1, Site Location Map). The purpose of our investigation was to identify and evaluate the existing geotechnical conditions at the site and provide geotechnical recommendations relative to the design and construction of the planned parking lot improvements. Based on our discussions and review of the preliminary site plans (Hofman, 2014), it is our understanding that the proposed improvements will include pervious concrete pavement, pervious paver pavement and DG pavement for overflow parking, a small retaining wall, new drainage and bio-swales, concrete sidewalks, a new trash bin, a shade structure, site lighting and landscaping. For the design of the various parking lot pavement sections, we are assuming a traffic index (TI) of 4.5, and that the proposed finish grades of the improvements will remain the same (Le., only minor cuts and fills). 3934 Murphy Canyon Road, Suite 8205 • San Diego, CA 92123-4425 858.292.8030. Fax 858.292.0771 I I I I I I I I I I I I I I I I I I I 10693.001 Site Location The roughly square shaped site is located in an undeveloped area immediately north of the existing Agua Hedionda Lagoon Foundation facility. The site is bounded on the east by Cannon Road, on the south by an existing paved parking lot, on the west and northwest by open space (Figure 2). The site is currently occupied by sparse vegetation. In general, the area for the proposed parking lot improvements is relatively flat with elevations ranging from 55 to 60 feet above mean sea level (msl). Along the northern perimeter, there is an ascending slope (approximately 2H:1V), and a small descending slope (approximately 2H:1V) along the eastern perimeter. Overhead high power lines also traverse the western portion of the site. The coordinates for the site are generalized as: Latitude: 33.14051° N Longitude: 117.30724° W Subsurface Investigation and Laboratory Testing Our subsurface exploration of the site was performed on May 5, 2014, and consisted of excavating, logging, and sampling of 2 small-diameter hand augured exploratory borings. The borings (HA-1 and HA-2) were excavated to a depth of approximately 4 feet below the existing ground surface (bgs). It should be noted that in 2011, we also performed three field percolation tests (FPT-1 through FPT-3) on the site to evaluate the existing on site soils for potential infiltration of storm water. The approximate locations of the borings and the field percolation tests are presented on the Field Exploration Map (Figure 2), and the boring logs and field percolation tests results are presented in Appendix B. During the excavation of the exploratory borings, an engineer from our firm logged the borings and collected representative samples at appropriate intervals for laboratory testing. After logging and sampling, the exploratory borings were backfilled with native soil. Laboratory testing was performed on representative samples to evaluate the soluble sulfate content, and to determine a preliminary R-value for the on-site subgrade soils (in accordance with Caltrans Test Method 301). A discussion of the laboratory tests performed and a summary of the laboratory test results are presented in Appendix C, and on boring logs as appropriate. -2-Leighton I I I I I I I I I I I I I I I I I I I 10693.001 Summary of Findings Based on our explorations and review of original site grading documents, the majority of the site is generally underlain by generally underlain by the Santiago Formation with relative a thin layer of surface fill and topsoil. In the southwestern portion of the site, there is documented fill, ranging from 1 to over 8 feet, that was placed during the site's initial grading in the late 1990s (POC, 2001). The as-graded report, prepared by Pacific Soils Engineering, indicates that engineering observations and testing of the fill soils were provided at the time of grading (PSE, 1999). The on-site soil generally consisted of grey brown to brown, dry to moist, loose to dense, silty sand with clay. Based on a visual observation of the collected soil samples, the soil generally ranges from very low to medium expansion potential. The results of the field percolation tests indicated that the site soils have a percolation rate ranging from approximately 50 to 125 minutes per inch (mpi) (Leighton, 2012). Preliminary laboratory testing indicates that the near surface soils have an R-value of approximately 19. Laboratory testing also indicated that the soil samples have soluble sulfate contents ranging from less than 0.015 to 0.03 percent (by weight in soil), which is a negligible degree of corrosivity on concrete. Based on our experience on similar projects and our site specific exploration; the upper 1 to 2 feet of the native soil and documented fill are considered compressible. Recommendations for remedial grading of these soils are provided in the following sections of this report. It should be note that ground water was not observed in the exploration borings performed during our investigation (total maximum depth explored 4 feet bgs). Groundwater is not considered a site constraint for the proposed improvements. However, perched ground water levels may develop and fluctuate during periods of precipitation. Faulting and Seismicity Our review of available geologic literature (Appendix A) indicates that there are no known Significant or active or potentially active faults transecting, or projecting toward the site. The nearest active fault is the Rose Canyon fault zone located approximately 6 miles west of the site (Blake, 2000). -3-Leighton I I I I I I I I I I I I I I I I I I I 10693.001 The effect of seismic shaking may be mitigated by adhering to the California Building Code and state-of-the-art seismic design practices of the Structural Engineers Association of California. Provided below in Table 1 are the spectral acceleration parameters for the project determined in accordance with the 2010 CBC (CBSC, 2010) utilizing Figures 1613.5(3) and 1613.5(4). Table 1 2010 CSC Mapped Spectral Acceleration Parameters Site Class D Fa = 1.06 Site Coefficients Fv = 1.58 Ss = 1.101g Mapped MCE Spectral Accelerations S1 = 0.424g SMS = 1.167g Site Modified MCE Spectral Accelerations SM1 = 0.668g Sos = 0.778g Design Spectral Accelerations S01 = 0.445g Utilizing ASCE Standard 7-10, in accordance with Section 11.8.3, the following additional parameters for the peak horizontal ground acceleration are associated with the Geometric Mean Maximum Considered Earthquake (MCEG). The mapped MCEG peak ground acceleration (PGA) is 0.431g for the site. For a Site Class 0, the FpGA is 1.069 and the mapped peak ground acceleration adjusted for Site Class effects (PGAM) is 0.461 g for the site. It should be noted that secondary seismic hazards for the site, which include soil liquefaction, seismically-induced settlement, lateral displacement, surface manifestations of liquefaction, landsliding, seiches, and tsunamis, are considered low or nil based on the underlying geology and our experience in the vicinity. Conclusions Based on the results of our geotechnical investigation of the site, it is our opinion that the proposed improvements are feasible from a geotechnical standpoint, provided the -4-Leighton I I I I I I I I I ·1 I I I I I I I I I 10693.001 following conclusions and recommendations are incorporated into the project plans and specifications. Generally loose soils having depths of up to approximately 1 to 2 feet locally underlie the site and are considered compressible. Therefore, these soils are not considered suitable for the support of structural loads or the support of engineered fill soils and site improvements in their present condition. Earthwork Recommendations We anticipate that earthwork at the site will consist of site preparation, shallow excavation and fill operations. We recommend that earthwork on the site be performed in accordance with the following recommendations and the General Earthwork and Grading Specifications for Rough Grading included in Appendix D. In case of conflict, the following recommendations supersede those in Appendix D. Potentially compressible soils at the site may settle as a result of wetting or settle under the surcharge of engineered fill and/or structural loads supported on shallow foundations. Therefore, we recommend a removal and recompaction of the upper 1 to 2 feet of the existing fill beneath the new pavement areas, or proposed structure. The lateral limits of the removal bottom should extend at least 5 feet beyond the limits of grading, where possible. The bottom of all removals should be evaluated by a Certified Engineering Geologist to confirm conditions are as anticipated. Prior to grading, all areas to receive structural fill, engineered structures, or hardscape should be cleared of surface and subsurface obstructions, including any existing debris and undocumented, loose, compressible, or unsuitable soils, and stripped of vegetation. Removed vegetation and debris should be properly disposed off site. All areas to receive fill and/or other surface improvements should be scarified to a minimum depth of 8 inches, brought to optimum or above-optimum moisture conditions, and recompacted to at least 90 percent relative compaction based on ASTM Test Method 01557. In general, the soil that is removed may be reused and placed as engineered fill provided the material is moisture conditioned to above optimum moisture content, and then recompacted prior to additional fill placement or construction. Soil utilized as fill should be free of oversized rock, organic materials, and deleterious debris. Rocks greater than 6 inches in diameter should not be placed within 2 feet of finished grade. Fill should be moisture conditioned to at least 2 percent above the optimum moisture -5-Leighton I I I I I "I I I I I I I I I I I I I I 10693.001 content and compacted to 90 percent or more relative compaction, in accordance with ASTM D 1557. Although the optimum lift thickness for fill soils will be dependent on the type of compaction equipment utilized, fill should generally be placed in uniform lifts not exceeding approximately 8 inches in loose thickness. In vehicle pavement and trash enclosure areas the upper 12 inches of subgrade soils should be scarified then moisture conditioned to a moisture content above optimum content and compacted to 95 percent or more of the maximum laboratory dry density, as evaluated by ASTM D 1557. Foundation Recommendations At the time of drafting this report, the specific location and type of site structures and potential foundation loading were not known. However, based on our discussions, we recommend that proposed structural improvements (i.e., site walls, small retaining walls and foundations for site lighting) be constructed with conventional foundations (continuous and isolated spread footings). Foundations are designed in accordance with structural considerations and the following recommendations. These recommendations assume that the soils encountered within 5 feet of surface grade have a low to medium potential for expansion (EI<90). If more expansive materials are encountered and selective grading cannot be accomplished, revised foundation recommendations may be necessary. The foundation recommendations below assume that the all building foundations will be underlain by properly compacted fill or undisturbed Santiago Formation. Footings should extend a minimum of 18 inches beneath the lowest adjacent finish grade. At these depths, footings may be designed for a maximum allowable (FS ~3) bearing pressure of 2,000 pounds per square foot. The allowable pressures may be increased by one-third when considering loads of short duration such as wind or seismic forces. The minimum recommended width of footings is 18 inches for continuous footings and 18 inches for square or round footings. Continuous footings should be designed in accordance with the structural engineer's requirements and have a minimum reinforcement of four No. 5 reinforcing bars (two top and two bottom). Reinforcement of individual column footings should be per the structural requirements. We recommend a minimum horizontal setback distance from the face of slopes for all structural foundations, footings, and other settlement-sensitive structures as indicated -6-Leighton I I I I I I I I I ·1 I I I I I I I I I 10693.001 on the Table 2 below. The minimum recommended setback distance from the face of retaining wall is equal to the height of the retaining wall. This distance is measured from the outside bottom edge of the footing, horizontally to the slope or retaining wall face, and is based on the slope or wall height. However, the foundation setback distance may be revised by the geotechnical consultant on a case-by-case basis if the geotechnical conditions are different than anticipated. Table 2 Minimum Foundation Setback from Slope Faces Slope Height Setback less than 5 feet 5 feet 5 to 15 feet 7 feet Please note that the soils within the structural setback area possess poor lateral stability, and improvements (such as retaining walls, sidewalks, fences, pavements, etc.) constructed within this setback area may be subject to lateral movement and/or differential settlement. Potential distress to such improvements may be mitigated by providing a deepened footing or a grade beam foundation system to support the improvement. In addition, open or backfilled utility trenches that parallel or nearly parallel structure footings should not encroach within an imaginary 1:1 (horizontal to vertical) downward sloping line starting 9 inches above the bottom edge of the footing and should also not be located closer than 18 inches from the face of the footing. Deepened footings should meet the setbacks as described above. Also, over-excavation should be accomplished so that deepening of footings to accomplish the setback will not introduce a cut/fill transition bearing condition. Pervious Paver Pavement In general, the pavers should be installed in accordance with the manufacturer's recommendations and specifications with concrete confinement curbs. In addition, we recommend using solid concrete interlocking pavers specifically designed for traffic loading applications (Le., paver thickness of 3-1/8 inches). -7-Leighton I I I I I I I I I I I I I I I I I I I 10693.001 Based on the results of the preliminary R-value testing, traffic index (TI) of 4.5 and assuming that the parking lot and driveway pavement surface will be sloped at least 2 percent, we recommend that the pervious concrete pavers be underlain by a 2-inch layer of ASTM No.8 Stone (bedding layer), over a minimum 8-inch layer of densified ASTM No. 57 Stone (open-graded base), over a non-woven filter fabric (Mirafi 140N, or equivalent). In addition, the subgrade surface supporting the open-graded base layer should be compacted to at least 95 percent relative compaction, and sloped at least 2 percent towards a perimeter subdrain or down gradient transition subdrain. If the pavement surface slope is less than 2 percent (Le., flatter), intermediate subdrains are recommended. For subdrains associated with pervious pavers, we recommend that they be installed directly below the open-graded base layer. The subdrain should include a 3-inch diameter perforated Schedule 40 PVC pipe at the bottom a relatively shallow trench. The trench for the subdrain should be approximately 12-inch wide, extend at least at least 6 inches below the open-graded base layer, lined with a non-woven filter fabric (Mirafi 140N, or equivalent) and backfilled with % inch gravel. In addition, the subdrain trench bottom and perforated pipe should be sloped to drain to an appropriate outlet. Pervious Concrete Pavement For the pervious concrete pavement section, we recommend using at least 7 inches of pervious concrete underlain by a minimum of 4.0 inches of densified ASTM No. 57 Stone (open-graded base), over a non-woven filter fabric (Mirafi 140N, or equivalent). The pervious concrete should consist of a 3,000-psi concrete mix that produces a minimum modulus of rupture of 400-psi. Note that the upper 12 inches of subgrade soil should be compacted to a relative compaction of at least 95 percent (based on ASTM Test Method D1557). In addition, the subgrade surface supporting the aggregate base should be sloped at least 2 percent towards a perimeter and/or down gradient transition subdrains. For the subdrains associated with pervious concrete, we recommend that they be installed directly below the open-graded base to drain the collected water. As discussed above, the subdrain should include a 3-inch diameter perforated Schedule 40 PVC pipe at the bottom a relatively shallow trench. The trench for the subdrain should be approximately 12-inch wide, extend at least at least 6 inches below the aggregate base layer, lined with a non-woven filter fabric (Mirafi 140N, or equivalent), backfilled with % inch gravel and sloped to drain to an appropriate outlet. -8-Leighton I I I I I I I I I I I I I I I I I I I 10693.001 OG Pavement For the decomposed granite COG) pavement section, we recommend using at least 3 inches of OG underlain by a minimum of 8.0 inches of Class 2 Aggregate Base. Similar to the other pavement sections above, the upper 12 inches of subgrade soil and aggregate base should be compacted to a relative compaction of at least 95 percent (based on ASTM Test Method 01557). In addition, the OG surface should be compacted to a relative compaction of at least 95 percent (based on ASTM Test Method 01557). It should be noted that regular maintenance of the OG pavement section will be required, and that relatively minor storm events could erode and/or damage the OG surface. Concrete Flatwork Concrete sidewalks and other fJatwork (including construction joints) should be designed by the project civil engineer and should have a minimum thickness of 4 inches. For all concrete fJatwork, the upper 12 inches of subgrade soils should be moisture conditioned to at least 2 percent above optimum moisture content and compacted to at least 90 percent relative compaction based on ASTM Test Method 01557 prior to the concrete placement. Trash Enclosure Approach and Bin For areas subject to unusually heavy truck loading (Le., trash trucks), we recommend a full depth of Portland Cement Concrete (PCC) section of 7.5 inches in accordance with the City of Carlsbad guidelines. Similar to the other pavement sections above, the upper 12 inches of subgrade soil should be processed and recompacted to a relative compaction of at least 95 percent (based on ASTM Test Method 01557). We recommend that sections be as nearly square as possible. A mix that provides a 600 psi modulus of rupture should be utilized. The actual pavement design should also be in accordance with ACI criteria. All pavement section materials should conform to and be placed in accordance with the latest revision of the Greenbook and American Concrete Institute (ACI) codes and guidelines. -9-Leighton I I I I I I I I I I I I I I I I I I I 10693.001 Retaining Wall Lateral Earth Pressures For design purposes, the following lateral earth pressure values for level backfill are recommended for retaining walls backfilled with and bearing against on-site soils or approved granular material of very low to low expansion potential. Table 3 Retaining Wall Equivalent Fluid Weight (pct) Conditions Level Active 36 At-Rest 55 300 Passive (Maximum of 3 kst) Unrestrained (yielding) cantilever walls up to 4 feet in height should be designed for an active equivalent pressure value provided above. In the design of walls restrained from movement at the top (nonyielding) such as basement walls, the at-rest pressures should be used. If conditions other than those covered herein are anticipated, the equivalent fluid pressure values should be provided on an individual case basis by the geotechnical engineer. A surcharge load for a restrained or unrestrained wall resulting from automobile traffic may be assumed to be equivalent to a uniform pressure of 75 psf which is in addition to the equivalent fluid pressure given above. For other uniform surcharge loads, a uniform pressure equal to 0.35q should be applied to the wall (where q is the surcharge pressure in pst). The wall pressures assume walls are backfilled with free draining materials and water is not allowed to accommodate behind walls. Typical retaining wall drainage design is illustrated in Appendix C. Wall backfill should be compacted by mechanical methods to at least 90 percent relative compaction (based on ASTM D1557). Wall footings should be designed in accordance with the foundation design recommendations and reinforced in accordance with structural considerations. For all retaining walls, we recommend a minimum horizontal distance from the outside base of the footing to daylight of 7 feet. Lateral soil resistance developed against lateral structural movement can be obtained -10-Leighton I I I I I I I I I I I I I I I I I I I 10693.001 from the passive pressure value provided abbve. Further, for sliding resistance, the friction coefficient of 0.35 may be used at the concrete and soil interface. These values may be increased by one-third when considering loads of short duration including wind or seismic loads. The total resistance may be taken as the sum of the frictional and passive resistance provided that the passive portion does not exceed two-thirds of the total resistance. The geotechnical consultant should approve any backfill materials that will be utilized prior to the backfill placement operations. It is the contractor's responsibility to provide representative samples of the selected backfill material. For the design of mechanically stabilized earth (MSE) or Keystone retaining walls greater than 3 feet tall, we recommend using the following soil parameters. Table 4 Retaining Wall Soil Parameters Soil Parameter Reinforced Retained Zone Foundation Zone Zone Internal Friction Angle 28 28 28 (degrees) Cohesion (psf) 0 50 50 Total Unit Weight (pcf) 128 125 125 Additional details relevant to the design of the MSE wall are presented on Detail G - Segmental Retaining Walls in Appendix D -General Earthwork and Grading Specifications. In addition, we recommend that water should be prevented from infiltrating into the reinforced soil zone (Le., no unlined bio-swales or other LID measures) in wall greater than 3 feet tall. All drains and swales should outlet to suitable locations as determined by the project civil engineer. In general, the project civil engineer should verify that the subdrain is connected to the proper drainage facility. Slope Maintenance Guidelines It is the responsibility of the owner to maintain the slopes, including adequate planting, proper irrigation and maintenance, and repair of faulty irrigation systems. To reduce the -11-Leighton I I I I I I I I I I I I I I I I I I I 10693.001 potential for erosion and slumping of graded slopes, all slopes should be planted with ground cover, shrubs, and plants that develop dense, deep root structures and require minimal irrigation. Slope planting should be carried out as soon as practical upon completion of grading. Surface-water runoff and standing water at the top-of-slopes should be avoided. Oversteepening of slopes should also be avoided during construction activities and landscaping. Maintenance of proper drainage, undertaking of improvements in accordance with sound engineering practices, and proper maintenance of vegetation, including regular slope irrigation, should be performed. Slope irrigation sprinklers should be adjusted to provide maximum uniform coverage with minimal of water usage and overlap. Overwatering and consequent runoff and ground saturation should be avoided. If automatic sprinklers systems are installed, their use must be adjusted to account for rainfall conditions. Trenches excavated on a slope face for any purpose should be properly backfilled and compacted in order to obtain a minimum of 90 percent relative compaction, in accordance with ASTM Test Method D1557. Observation/testing by the geotechnical consultant during trench backfill are recommended. A rodent-control program should be established and maintained. Prior to planting, recently graded slopes should be temporarily protected against erosion resulting from rainfall, by the implementing slope protection measures such as polymer covering, jute mesh, etc. Control of Surface Waters Surface drainage should be controlled at all times and carefully taken into consideration during precise grading, landscaping, and construction of site improvements. Positive drainage (e.g., roof gutters, downspouts, area drains, etc.) should be provided to direct surface water away from structures and improvements and towards the street or suitable drainage devices. Ponding of water adjacent to structures or pavements should be avoided. Roof gutters, downspouts, and area drains should be aligned so as to transport surface water to a minimum distance of 5 feet away from structures. The performance of structural foundations is dependent upon maintaining adequate surface drainage away from structures. Water should be transported off the site in approved drainage devices or unobstructed swales. We recommend a minimum flow gradient for unpaved drainage within 5 feet of structures of 2 percent sloping away. -12-Leighton I I I I I I I I I I I I I I I I I I I 10693.001 The impact of heavy irrigation or inadequate runoff gradient can create perched water conditions, resulting in seepage or shallow ground water conditions where previously none existed. Maintaining adequate surface drainage and controlled irrigation will significantly reduce the potential for nuisance-type moisture problems. To reduce differential earth movements such as heaving and shrinkage due to the change in moisture content of foundation soils, which may cause distress to a structure and improvements, moisture content of the soils surrounding the structure should be kept as relatively constant as possible. Below grade planters should not be situated adjacent to structures or pavements unless provisions for drainage such as catch basins and drains are made. All area drain inlets should be maintained and kept clear of debris in order to function properly. In addition, landscaping should not cause any obstruction to site drainage. Rerouting of drainage patterns and/or installation of area drains should be performed, if necessary, by a qualified civil engineer or a landscape architect. Plan Review Final project grading and foundation plans should be reviewed by Leighton Consulting, Inc. as part of the design development process to ensure that recommendations in this report are incorporated in project plans. Construction Observations The interpolated subsurface conditions should be checked by Leighton Consulting, Inc. in the field during construction. Construction observation of all onsite excavations and field density testing of all compacted fill should be performed by a representative of this office. We recommend that a/l excavations be mapped by the geotechnical consultant during grading to determine if any potentially adverse geologic conditions exist at the site Limitations The conclusions and recommendations in this report are based in part upon data that were obtained from a limited number of observations, site visits, excavations, samples, -13-Leighton I I I I I I I I I I I I I I I I I I I 10693.001 and tests. Such information is by necessity incomplete. The nature of many sites is such that differing geotechnical or geological conditions can occur within small distances and under varying climatic conditions. Changes in subsurface conditions can and do occur over time. Therefore, the findings, conclusions, and recommendations presented in this report can be relied upon only if Leighton Consulting, Inc. has the opportunity to observe the subsurface conditions during grading and construction of the project, in order to confirm that our preliminary findings are representative for the site. If you have any questions regarding our report, please contact this office. We appreciate this opportunity to be of service. Respectfully submitted, LEIGHTON CONSULTING, INC. William D. Olson, RCE 45283 Associate Engineer Mike D. Jensen, CEG 2457 Project Geologist Attachments: Figure 1 -Site Location Map Figure 2 -Field Exploration Map Appendix A -References Appendix B -Boring Logs Appendix C -Laboratory Testing Procedures and Test Results Appendix D -General Earthwork and Grading Specifications Distribution: (4) Addressee -14-Leighton I I I I I I Figures I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I Project: 10693.001 Eng/Geol: WDO/MDJ Scale: 1 " = 2,000 ' Date: July 2014 Base Map:ESRI Resources Center, 2014 Author: (mmurphy) Map Saved as P.ldraftlngI106931001lGISloL2014-05-13\Flgure1 mxd on 5/1312014 2:56:27 PM SITE LOCATION MAP Agua Hedionda Lagoon Foundation Parking Lot Expansion Faraday and Cannon Road Carlsbad California Figure 1 Leighton I I I I I I I I I I I I I I I I I I I I I I I I I I Appendix A I References I ·1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I 10693.001 APPENDIX A References American Concrete Institute, 2008, Building Code Requirements for Structural Concrete (ACI 318-08) and Commentary. Associated Society of Civil Engineers (ASCE), 2005, ASCE/SEI 7-05, Minimum Design Loads for Buildings and Other Structures. Blake, T.F., 2000, EQFAULTforWindows Version 3.00a, with updated database 2010. California Building Standards Commission (CBSC), 2010a California Building Code, Based on 2009 International Building Code. ----, 2010c, California Green Building Standards Code, dated June. California Department of Transportation (Caltrans), 2003, Corrosion Guidelines Version 1.0, California Department of Transportation Division of Engineering Services Materials and Testing Services Corrosion Technology, September 2003. California Geologic Survey (CGS), 2008, Guidelines for Evaluating and Mitigating Seismic Hazards in California Special Public 117a. Caltrans, 2007, Storm Water Quality Handbook: Project Planning and Design Guides, dated May 2007. County of San Diego, 2008, Department of Environmental Health, Land and Water Quality Division Design Manual for Onsite Wastewater Treatment Systems, dated June 26. ----, 2007a, Low Impact Development Handbook -Stormwater Management Strategies, dated December 31, 2007. ----, 2007b, Low Impact Development Appendices -San Diego Considerations and LID Fact Sheets, dated December 31, 2007. Hart, E.W., and Bryant, W.A., 2007, Special Publication 42, Fault Rupture Hazard Zones in California, Alquist-Priolo Earthquake Fault Zoning Act with Index to Earthquake Fault Zone Maps, Interim Revision 2007. A-1 I I I I I I I I I I I I I I I I I I I 10456.001 APPENDIX A (Continued) Hofman, 2014, Preliminary Precise Grading Plans for Agua Hediondia Lagoon Foundation Overflow Parking Lot, Project No. SPD98-15, Sheet 3 of 3, plot date March 27,2014. Kennedy, M.P., 1975, Geology of the San Diego Metropolitan area, California Division of Mines and Geology, Bulletin 200. Leighton, 2012, Field Percolation Testing Results, Proposed Parking Lot Expansion Area, Agua Hedionda Lagoon Foundation, Carlsbad, California, PJN 603336-001, dated March 29,2012. Treiman, J.A., 1993, The Rose Canyon Fault Zone, Southern California: California Division of Mines and Geology, Open-File Report 93-02, 45 p. PDC, 2001, As-Built Grading and Erosion Control Plans for: Kelly Ranch, Village F, Project No. SPD98-15, Drawing No. 372-4A, Sheets 1-4, dated August 1, 2001. PSE, 1999, Final Grading Report, Kelly Ranch Area F, Agua Hediondia Lagoon Nature Center, Carlsbad, California, WO 400607, dated January 8,1999. United States Geologic Survey (USGS), 2010, Java Ground Motion Parameter Calculator, Version 5.1.0. A-2 8 I I I I I I I I I I I I I I I I I I I I I I I- I I I Appendix B I Boring Logs I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I Project No. Project Drilling Co. Drilling Method Location c .9 .. C,) J:: .. :em 1GGI Q,GI c.o >GI GIGI I!!..J GIlL OlL CJ iii N S ~~::)::~ ~ L/: })) J:: - ~ ~ .. ~. .. " ~~~o( 'W ~Ktlo ~~ I" ~. 6 ~ ~ i7 - - 20- - - - - 25- - - - - ... I5A;P;~~~~~PLE C CORE SAMPLE G GRAB SAMPLE R RING SAMPLE GEOTECHNICAL BORING LOG KEY KEY TO BORING LOG GRAPHICS Date Drilled Logged By .. -------------Hole Diameter Ground Elevation Sampled By 0 III ~ GI~ 0--:-SOIL DESCRIPTION II) GI GI Z Ill=-II) ... -lIlen 'tl GI ~I,) c .... ::l" n!' This Soil Description applies only to a location of the exploration at the .... c -0 ::l Q. 0': GIl,) IIlGl o· .... oc. .-.. _en time of sampling. Subsurface conditions may differ at other locations ~ E £i:ifD ~ Oc '0:) and may change with time. The description is a simplification of the n! ... :!EO actual conditions encountered. Transitions between soil types may be en GI 0 0 en-a.. gradual. l\sphaltic concrete Portland cement concrete IIlv~T:~~'~i~~~'~~!~:a~o cra~dium plasticity; gravelly clay; sandy II v . clay; high ... ,g~L'V"J' fat clays Organic clay; medium to plastiCity, organic silts Inorganic silt; clayey silt with low plasticity Inorganic silt; diatomaceous fine sandy or silty soils: elastic silt Clayey silt to silty clay Well-graded gravel; gravel-sand mixture, little or no fines Poorly graded gravel; gravel-sand mixture, little or no fines Silty gravel: gravel-sand-silt mixtures Clayey gravel; gravel-sand-clay mixtures Well-graded sand: gravelly sand, little or no fines Poorly graded sand: gravelly sand, little or no fines Silty sand; graded .,,,,nl'l_,,iI •. mixtures Clayey sand; _, mixtures Bedrock Ground water encountered at time of drilling Bulk Sample Core Sample Grab Sample Modified California Sampler (3" 0.0., 2.5 1.0.) Shelby Tube Sampler (3" 0.0.) Standard Penetration Test SPT (Sampler (2" 0.0., 1.4" 1.0.) Sampler Penetrates without Hammer Blow 'TY~EOF TESTS: -200 % FINES PASSING OS DIRECT SHEAR SA SIEVE ANALYSIS AL ATIERBERG LIMITS EI EXPANSION INDEX SE SAND EQUIVALENT CN CONSOLIDATION H HYDROMETER SG SPECIFIC GRAVITY CO COLLAPSE MD MAXIMUM DENSITY SS SOLUBLE SULFATE ~ ~ '0 GI Co ~ ~ ~~~~::~~~SAMPLE g~ ~2~~~~~~ TRIAXIAL ~C ~~~~~1PENETROMETER 4 * * * This log is a part of a report by Leighton and should not be used as a stand.alone document. * * II' Page 1 of 1 I I I I I I I I I I I I I I I I I I I Project No. Project Drilling Co. Drilling Method Location c .S! .... CJ &. .... :CO) 1ijQl 'Q,QI C.O >QI (1)(1) e..J (l)lL OlL jjj C) N 5 o· -'. 55--' . - 5- - 50 - - 10- - 45-- - - 15- - 40· - - 20- - 35 - - - 25- - 30 - - - SAMPdPTYPES: B BULK SAMPLE C CORE SAMPLE G GRAB SAMPLE R RING SAMPLE GEOTECHNICAL BORING LOG HA-1 10693-001 Date Drilled 5-5-14 Agua Hedionda Lagoon Foundation Logged By SLR Hole Diameter 4" Hand Auger Ground Elevation 57' West tI) 0 m i':' QI Z tI)&' 'in 'C QI ~CJ c .... ::2 Q. 0":: QlCJ .... oc. ~ E ijico lIS ... i!' rn (I) 0 0.. , , B-1 -----1------ J I I QI~ u;..-o;-... ~ 111m ::2 .... lIS' .... c -0 111(1) o· .-.... _rn oc :=0 '0:;; 0 rn- 8M ----8M Sampled By ...-SLB SOIL DESCRIPTION This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual. ARTIFICIAL FILL @ 0-2": Decomposed Granite at surface @ 2"-4"; Brown silty SAND, loose, damp to moist with some organics '-----:.@... ~~5~ .!:i9!!t..P~~:9.r~,Jo.Q~!Q !!l~i.!!!TI_d~n~e _____ ...- SANTIAGO FORMATION @ 2.5'-4'; Brown to gray silty SAND with clay, moist, dense Total Depth = 4 Feet No groundwater encountered at time of drilling Backfilled with spoils 5/5/14 TYPE OF TESTS: -200 % FINES PASSING OS DIRECT SHEAR SA SIEVE ANALYSIS AL ATTERBERG LIMITS EI EXPANSION INDEX SE SAND EQUIVALENT CN CONSOLIDATION H HYDROMETER SG SPECIFIC GRAVITY CO COLLAPSE MD MAXIMUM DENSITY SS SOLUBLE SULFATE S SPLIT SPOON SAMPLE CR CORROSION PP POCKET PENETROMETER T TUBE SAMPLE CU UNDRAINED TRIAXIAL RV R VALUE RV,SS * • • This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Page 1 of 1 I I I I I I I I I I I I I I I I I I I GEOTECHNICAL BORING LOG HA-2 10693-001 Agua Hedionda Lagoon Foundation Date Drilled Logged By 5-5-15 SLR Project No. Project Drilling Co. Hole Diameter --,-4'_' ____ _ Drilling Method -!..H~a~n~d..!.-A!!:u!""g~er,--________________ _ Ground Elevation .-=.56::::..' ____ _ Location East c u .2 .... .c ... :CO) liQ) .... Q) o.Q) 0.0 >Q) ~LL ~...J G)LL iii (!) ,N s 0 55· -'. -" . - 5- 50 - - - - 10- 45 - - - - 15- 40 - - - - 20- 35 - - - - 25- 30 - - - - d z G) ii E (II en B-1 ---1--- Sampled By 5LR ui-:-SOIL DESCRIPTION gj~ c:;q This Soil Description applies only to a location of the exploration at the _en time of sampling. SubsUliace conditions may differ at other locations ·O=:) and may change with time. The descnption is a simplification of the en-actual conditions encountered. Transitions between soil types may be SM 8M gradual. ARTIFICIAL FILL @ 0-3": Gravel import/soil mix at surface @ 3"-2.5': Gray silty SAND, damp to moist, loose to medium dense ~----------------------------SANTIAGO FORMATION @2.S'-4': Brown to gray silty SAND with clay, moist, dense Total Depth = 4 Feet No groundwater encountered at time of drilling Backfilled with spoils 5/5/14 RV,SS SAMPdPl~-~e-s:-~--+~--E--OF-TLELS-TS-:~---.L--~---~-------------_____________________ L-_~ B BULK SAMPLE ·200 % FINES PASSING DS DIRECT SHEAR SA SIEVE ANALYSIS ~~. C CORE SAMPLE AL ATTERBERG LIMITS EI EXPANSION INDEX SE SAND EQUIVALENT G GRAB SAMPLE CN CONSOLIDATION H HYDROMETER SG SPECIFIC GRAVITY R RING SAMPLE CO COLLAPSE MD MAXIMUM DENSITY SS SOLUBLE SULFATE S SPLIT SPOON SAMPLE CR CORROSION PP POCKET PENETROMETER T TUBE SAMPLE CU UNDRAINED TRIAXIAL RV R VALUE * If * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Page 1 of 1 I I I I I' I I I I I I I I I I I I I I I I I I I I I 'I I I I I I I I I I I I, I I Appendix C Laboratory Testing Procedures and Test Results I I I I I I I' I I I I I I I I I I I I 10693.001 APPENDIX C Laboratory Testing Procedures and Test Results nRn-Value: The resistance "Rn-value was determined by the California Materials Method CT301 for base, subbase, and basement soils. The samples were prepared and exudation pressure and "Rn-value determined. The graphically determined nR"-value at exudation pressure of 300 psi is reported. Sample Location Sample Description R-Value HA-1 & HA-2 Grey-Brown Silty Sand (SM) wI clay 19 (composite) Soluble Sulfate Content: The soluble sulfate contents of selected samples were determined by standard geochemical methods (Caltrans Test Method CT417). The test results are presented in the table below: Sulfate Potential Degree Sample Location Sample Description Content (ppm) of Sulfate Attack I HA-1 (4" to 48") I Grey-Brown Silty Sand (SM) wI clay I <150 I Negligible I I HA-2 (4" to 48") I Grey-Brown Silty Sand (SM) wI clay I 300 I Negligible I C-1 a I I I I I I I ,I I- I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I Appendix D General Earthwork and Grading Specifications I I I I I I I I I I I I I I I I I I I LEIGHTON CONSULTING, INC. General Earthwork and Grading Specifications 1.0 General 1.1 Intent These General Earthwork and Grading Specifications are for the grading and earthwork shown on the approved grading plan(s) and/or indicated in the geotechnical report(s). These Specifications are a part of the recommendations contained in the geotechnical report(s). In case of conflict, the specific recommendations in the geotechnical report shall supersede these more general Specifications. Observations of the earthwork by the project Geotechnical Consultant during the course of grading may result in new or revised recommendations that could supersede these specifications or the recommendations in the geotechnical report(s). 1.2 The Geotechnical Consultant of Record Prior to commencement of work, the owner shall employ the Geotechnical Consultant of Record (Geotechnical Consultant). The Geotechnical Consultants shal! be responstb~e for reviewing the approved geotechnical report(s) and accepting the adequacy of the preliminary geotechnical findings, conclusions, and recommendations prror to the commencement of the grading. Prior to commencement of grading, the Geotechnical Consultant shalt review the "work plan" prepared by the Earthwork Contractor (Contractor) and schedule suffIcient personnel to perform the appropriate revet of observation, mapping, and compaction testing. During the grading and earthwork operations, the Geotechnical Consultant shall observe, map, and document the subsurface exposures to verify the geotechnical desIgn assumptions. If the observed conditions are found to be Significantly dIfferent than the interpreted assumptions during the design phase, the Geotechnical Consultant shall inform the owner, recommend appropriate changes in design to accommodate the observed conditions, and notify the review agency where required. Subsurface areas to be geotechnically observed, mapped, elevations recorded, and/or tested include natural ground after it has been cleared for receiving fill but before fill is placed, bottoms of all "remedial removal" areas, all key bottoms, and benches made on sloping ground to receive fill. The Geotechnical Consultant shall observe the moisture-conditioning and processing of the subgrade and fill materials and perform relative compaction testing of fill to determine the attained level of compaction. The Geotechnical Consultant shall provide the test results to the owner and the Contractor on a routine and frequent basis. -1- I I I I I I I I I I I I I I I I I I I LEIGHTON CONSULTING, INC. General Earthwork and Grading Specifications 1.3 The Earthwork Contractor The Earthwork Contractor (Contractor) shall be qualified, experienced, and knowledgeable in earthwork logistics, preparation and processing of ground to receive fill, moisture-conditioning and processing of fill, and compacting fill. The Contractor shall review and accept the plans, geotechnical report(s), and these Specifications prior to commencement of grading. The Contractor shan be solely responsible for performing the grading in accordance with the plans and specifications. The Contractor shalr prepare and submrt. to the owner and the Geotechnical Consultant a work. plan that indicates the sequence of earthwork grading, the number of "spreads" of work and the estimated quantities of daily earthwork contemplated for the site prior to commencement of gradtng. The Contractor shan inform the owner and the Geotechnical Consultant of changes in work schedules and updates to the work plan at least 24 hours in advance of such changes so that appropriate observations and tests can be planned and accomplfshed. The Contractor shall not assume that the Geotechnical Consultant is aware of an grading operations. The Contractor shaH have the sole responsibHfty to provide adequate equipment and methods to accomptish the earthwork in accordance with the applicable gradtng codes and agency ordinances, these SpeCifications, and the recommendations 10 the approved geotechnica( report(s) and grading ptan(s). If, in the opinion of the Geotechnical Consultant, unsatisfactory condfHons, such as unsuitable soil, improper moisture condition, inadequate compaction, insufficient buttress key size. adverse weather, etc., are resulting in a quality of work less than required in these spec,ftcations, the Geotechnical Consultant shalt reject the work and may recommend to the owner that construction be stopped until the conditions are rectified. 2.0 Preparation of Areas to be Filled 2.1 Clearing and Grubbing Vegetation, such as brUSh, grass, roots, and other deleterious material shall be sufficiently removed and properly disposed of in a method acceptable to the owner, governing agencies, and the Geotechnical Consultant. -2- I I I I I I I I I I I I I I I I I I I LEIGHTON CONSULTING, INC. General Earthwork and Grading Specifications The Geotechnical Consultant shall evaluate the extent of these removals depending on specific site conditions. Earth fill material shall not contain more than 1 percent of organic materials (by volume). No fill lift shall contain more than 5 percent of organic matter. Nesting of the organic materials shall not be allowed. If potentially hazardous materials are encountered, the Contractor shall stop work in the affected area, and a hazardous material specialist shall be informed immediately for proper evaluation and handling of these materials prior to continuing to work in that area. As presently defined by the State of California, most refined petroleum products (gasoline, dieseJ fuel, motor oil, grease, coolant, etc.) have chemical constituents that are considered to be hazardous waste. As such, the indiscriminate dumping or spillage of these fluids onto the ground may constitute a misdemeanor, punishable by fines andlor imprisonment, and shaft not be allowed. 2.2 Processing Existing ground that has been declared satisfactory for support of filt by the Geotechnical Consultant shalf be scarined to a minimum depth of 6 inches. Existing ground that tS not satisfactory shan be overexcavated as specified in the follow~ng section. Scarification shan continue until soils are broken down and free of farge clay lumps or dads and the working surface is reasonably uniform, flat, and free of uneven features that would inhibit uniform compaction. 2.3 Overexcavation In addition to removals and overexcavations recommended in the approved geotechnicat report(s) and the grading plan, soft, loose, dry, saturated, spongy, organic-r~ch, highly fractured or otherwise unsuitable ground shaH be overexcavated to competent ground as evaluated by the Geotechnical Consultant during grading. 2.4 Benching Where fills are to be placed on ground with slopes steeper than 5:1 (horizontal to vertical units), the ground shall be stepped or benched. Please see the Standard Details for a graphic illustration. The lowest bench or key shall be a minimum of 15 feet wide and at least 2 feet deep, into competent material as evaluated by the Geotechnical Consultant. Other benches shall be excavated a minimum height of 4 feet into competent material or as otherwise recommended by the Geotechnical -3- I I I I I I I I I I I I I I I I I I· I' LEIGHTON CONSULTING, INC. General Earthwork and Grading Specifications Consultant. Fill placed on ground sloping flatter than 5:1 shall also be benched or otherwise overexcavated to provide a flat subgrade for the fill. 2.5 Evaluation/Acceptance of Fill Areas All areas to receive fill, including removal and processed areas, key bottoms, and benches, shall be observed, mapped, elevations recorded, and/or tested prior to being accepted by the Geotechnical Consultant as suitable to receive fill. The Contractor shan obtain a written acceptance from the Geotechnical Consultant prior to fill placement. A licensed surveyor shall provide the survey control for determining elevations of processed areas, keys, and benches. 3.0 Fill Materia! 3.1 General Material to be used as fm shan be essentiaUy free of organic matter and other deleterious substances evaluated and accepted by the Geotechnical Consultant prior to placement So tis of poor quality, such as those with unacceptable gradaTIon, high expansion potential, or low strength shall be pfaced in areas acceptable to the Geot.ecnnicaf Consultant or mixed with other soils to achieve satisfactory fm material. 3.2 OverSize Oversize material defined as rock, or other iofredudble material with a maximum dimension greater than 8 inches, shall not be buried or placed in fill unless location" matertafs, and placement methods are specifically accepted by the Geotechnicat Consultant Placement operations shan be such that nesting of oversized matertat does not occur and such that oversize materia~ is completely surrounded by compacted or densified fill. Oversize material shall not be placed within 10 vertical feet of finish grade or within 2 feet of future utilities or underground construction. 3.3 Import If importing of fill material is required for grading, proposed import material shall meet the requirements of Section 3.1. The potential import source shall be given to the Geotechnical Consultant at least 48 hours (2 working days) before importing begins so that its suitability can be determined and appropriate tests performed. -4- I I I I I I I I I I I I I I I I I I I LEIGHTON CONSULTING, INC. General Earthwork and Grading Specifications 4.0 Fill Placement and Compaction 4.1 Fill Layers Approved fill material shall be placed in areas prepared to receive fill (per Section 3.0) in near-horizontal layers not exceeding 8 inches in loose thickness. The Geotechnical Consultant may accept thicker layers if testing indicates the grading procedures can adequately compact the thicker layers. Each layer shall be spread evenly and mixed thoroughly to attain relative uniformity of matenal and moisture throughout. 4.2 Fill Moisture Conditioning Ffli soils shall be watered, dried back, blended, and/or mixed. as necessary to attain a relatively uniform moisture content at or slightly over optimum. Maximum densrty and optimum soil moisture content tests shalf be performed in accordance with the American Society of Testing and Materials (ASTM Test Method D1557).. 4.3 Compaction of Fill After each layer has been morsture-condfti.oned. mixed, and evenly' spread, rt shan be uniformty compacted to not tess than 90 percent of maximum dry density' (ASTM Test Method D1557). Compaction eqUipment shaH be adequately sized and be eilher specifically designed for soff compaction or of' proven reliability to efficiently achieve the specified Jevel of compaction with uniformrly .. 4.4 Compaction of Fill Slopes In addition to normaJ compaction procedures specified above, compaction of slopes shall be accompfished by backrolling of stopes with sheepsfoot roHers at increments of 3 to 4 feet in fill elevation, or by other methods producing satisfactory results acceptable to the Geotechnical Consultant. Upon completion of grading, retattve compaction of the tilt out to the slope face, shall be at least 90 percent of maximum density per ASTM Test Method D1557. 4.5 Compaction Testing Field-tests for moisture content and relative compaction of the fill soils shall be performed by the Geotechnical Consultant. Location and frequency of tests shall be at the Consultant's discretion based on field conditions encountered. Compaction test locations will not necessarily be selected on a random basis. T est locations shall be selected to verify adequacy of compaction levels in areas that are judged to be prone to -5- I I I I I I I I I I I I I I I I I I I LEIGHTON CONSULTING, INC. General Earthwork and Grading Specifications inadequate compaction (such as close to slope faces and at the fill/bedrock benches). 4.6 Frequency of Compaction Testing Tests shall be taken at intervals not exceeding 2 feet in vertical rise and/or 1,000 cubic yards of compacted fill soils embankment. In addition, as a guideline, at least one test shall. be taken on slope faces for each 5,000 square feet of slope face and/or each 10 feet of vertical height of slope. The Contractor shall assure that fill construction is such that the testing schedule can be accomplished by the Geotechnical Consultant The Contractor shall stop or slow down the earthwork construction if these minimum standards are not met 4.7 Compaction Test Locations The Geotechnical Consultant shaU document the approximate elevation and horizontal coordinates of each test tocatfon. The Contractor shan coordinate with the project surveyor to assure that sufficient grade stakes are establfshed so that the Geotechntcat Consultant can determine the test locatjons with sufficient accuracy. At a minimum, two grade stakes within a hofizontaf distance of 100 reet and vertically tess than 5 feet apart from potential test rocations shaH be provided .. 5 . .0 Subdrain Installation Subdrain systems shall be insta[fed tn accordance with the approved geotechnical report(s), the grading plan" and the Standard Details. The Geotechnical Consultant may recommend addltfonaf subdrains and/or changes in subdrain extent, location, grade, or materia! depending on conditions encountered during grading. AU subdraifls shan be surveyed by a land surveyor/civil engineer for line and grade after installation and prior to buriaL Sufficient time should be allowed by the Contractor for these surveys. 6.0 Excavation Excavations, as well as over-excavation for remedial purposes, shall be evaluated by the Geotechnical Consultant during grading. Remedial removal depths shown on geotechnical plans are estimates only_ The actual extent of removal shall be determined by the Geotechnical Consultant based on the field evaluation of exposed conditions during grading. Where fill-aver-cut slopes are to be graded, the cut portion of the slope shall be made, evaluated, and accepted by the Geotechnical Consultant prior to placement of materials for construction of the fill portion of the slope, unless otherwise recommended by the Geotechnical ConSUltant. -6- I I I I I I I I I 'I I I I I I I I I I LEIGHTON CONSULTING, INC. General Earthwork and Grading Specifications 7.0 Trench Backfills 7.1 Safety The Contractor shall follow all OSHA and Cal/OSHA requirements for safety of trench excavations. 7.2 Bedding and Backfill All bedding and backfill of utility trenches shall be performed in accordance with the applicable provisions of Standard Specifications of Public Works Construction. Bedding material shall have a Sand Equivalent greater than 30 (SE>30). The bedding shall be placed to 1 foot over the top of the conduit and densified. Backfill shall be placed and denslfied to a minimum of 90 percent of reJatlve compaction from 1 foot above the top of the conduIt to the surface. The Geotechnical Consultant shaU test the trench backfill for relative compaction. At least one test snoufd be made for every 300 feet of trench and 2 feet of fill. 7.3 Uft Thickness Uft thickness of trench backfttr shalt nof. exceed those allowed in the Standard SpeCifications of Pubbc Works Construction unless the Contractor can demonstrate to the Geotechnical Consultant that the fill lift can be compacted to the mintmum relative compaction by his alternative equipment and method. 7.4 Observation and Testing The densification of the bedding around the conduits shalf be observed by the Geotechnical Consultant. -7- I I I I I I I I I I I I I I I I I I I FILL SLOPE _ .... -f:::~:::~~~:~:::::::§~ ---:-:-:COM PACfEfi:=-=-:-:-:=-:~ PROJECTED PLANE 1: 1 _..:-::=:=:::::=:::-:--:---:_:_:-:_-:-:-*:~ (HORIZONTAL·. VER1lCAL) -"'--:_"'--_"'--_-_-_-_~-:fLLJ;----=--~------::-.. --------_"":... ---------------~----------~-, MAXIMUM FROM TOE __ -:::::::::=:::=t=:=t:::=~_:_~-~-j:---,~"--- OF SLOPE TO _-:=:::::;""::=::::::;?:~::-:---z':---: APPROVED GROUND __ -:=:::::~~~~~:::= 0 REMOVE EXISTING~ • ..z..:-.:::::---------------_ UNSUITABLE GROUND SURFACE _ -_-:-f~~:::-BEN'CH l MA TERIAL . I -----~-------------= BENCH HEIGHT 9 ./ ---.--.. ' t --:"0_-::::':=:::=::==:;""::=:-f' (4 FEET TYPICAL) ~,,,,,,,.fi.=-·· 2 FEET::1I~~~~;:;~T KEY DEPTH BENCH (KEY) FILL -oVER-cuT SLOPE CUT -OVER-FILL SLOPE OVERBUILD AND...,.---~ TRIM BACK PROJECTED PLANE DESIGN SLOPE.---.~"': KEYING AND BENCHING REMOVE UNSUITABLE MATERIAL REMOVE UNSUITABLE MATERIAL UT FACE SHALL BE CONSTRUCTED PRIOR TO FILL PLACEMENT BENCHING SHALL 8E DONE WHEN SLOPE'S ANGLE IS EQUAL TO OR GREATER THAN 5: 1. MINIMUM BENCH HEIGHT SHALL BE 4 FEET AND MINIMUM FILL WIDTH SHALL 8E 9 FEET. GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAIL A I I I I I I I I I I I I I I I I I I OVERSIZE WINDROW • OVERSIZE ROCK IS LARGER THAN 8 INCHES IN LARGEST DIMENSION. ,. EXCAVATE A TRENCH IN THE COMPACTED FILL DEEP ENOUGH TO BURY ALL THE ROCK. ,. BACKFILL WITH GRANULAR SOIL JETTED OR FLOODED IN PLACE TO FILL ALL THE VOIDS. ,. DO NOT BURY ROCK WITHIN 10 FEET OF FINISH GRADE. • WINDROW OF BURIED ROCK SHALL BE PARALLEL TO THE FINISHED SLOPE. FINISH GRADE GRANULAR MA TERIAL TO BE DENSIFIED IN PLACE BY FLOODING OR JETTING. DETAIL JETTED OR FLOODED - - - - - GRANULAR MA TERIAL TYPICAL PROFILE ALONG WINDROW OVERSIZE ROCK DISPOSAL GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAIL B I I I I I I I I I I I I I I I I I I I BENCHING DESIGN FINISH GRADE SUBDRAIN TRENCH SEE DETAIL BELOW FIL TER FABRIC REMOVE UNSUITABLE MATERIAL (MIRAFI 140N OR APPROVED EQUIVALENT)- --!..-.!!!:p.:.... BEDDING SUBDRAtN DETAIL COLLECTOR PIPE SHALL BE MINIMUM 6" DIAMETER SCHEDULE 40 PVC PERFORATED PIPE. SEE STANDARD DETAIL D FOR PIPE SPECIFICATIONS FIL TER FABRIC (M1RAFI 140N OR APPROVED DETAIL Of CANYON SUBDRAIN OUTLET CANYON SUBDRAINS GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAIL C I I I I I I I I I I I I I I I I I I I 15' MIN. 'I OUTLET PIPES 4" {(1 NONPERFORATED PIPE, 100' MAX. O.C. HORIZONTALLY. 30' MAX O.C. VERTICALLY 12" MIN. OVERLAP FROM THE TOP HOG RING TIED EVERY 6 FEET CAL TRANS CLASS II PERMEABLE OR /12 ROCK (3 fTA 3/FT) WRAPPED IN FIL TER FABRIC 4" 0 TRENCH LOWEST SU8DRAIN SHOULD BE SITUATED AS LOW AS POSSIBLE TO ALLOW SUITABLE OUTLET T-CONNECTION FOR COLLECTOR PIPE TO OUTLET PIPE 6" MIN. COVER OUTLET PIPE -;;;;::-~::;:~r:=:~:.::: ~ON-PERFORA TED --:::-- 4"0 PERFORATED PIPE - PROVIDE POSITIVE SEAL AT THE JOINT L---4" MIN. FIL TER FABRIC ENVELOPE (MIRAFI 140 OR APPROVED EQUIVALENT) BEDDING SUBDRAIN TRENCH DETAil SU8DRAIN INSTALLATION -subdroin collector pipe sholl be installed with perforation down or, unless otherwise designated by the geotechnical consultant. Outlet pipes sholl be non-perforated pipe. The subdroin pipe sholl have at least 8 perforations uniformly spaced per foot. Perforation sholl be 1/4-" to 1/2" if drill holes are used. All subdrain pipes sholl have a grodient of ot least 2% towards the outlet. SUBORAIN PIPE -Subdroin pipe sholl be ASTM 02751, SOR 23.5 or ASTM 01527. Schedule 40, or ASTM 03034, SDR 23.5, Schedule 40 Polyvinyl Chloride Plastic (PVC) p,ipe. All outlet pipe sholl be placed in a trench no wider than twice the subdroin pipe. BUTTRESS OR REPLACEMENT FILL SUBDRAINS GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAIL D I I I I I I I I I I I I I I I I I I I CUT-FILL TRANSITION LOT OVEREXCAVATION --------------------------- REMOVE UNSUITABLE GROUND\-_ --- ---- " ------------;:----:::: -------COMPACTED Fll± ----..-"'---- - --~'_7_'~""7r'=->~~....J.<::.l.~~:Prl;9_.l "-------------:::----::::-~ ----------.;;---::::--<"< /' -------:",----~------------.;:;~----------------------:::' -- --- - ----.::::. /.X/' OVEREXCAVATE -_-_-_-_-_~-?~---" ',,-AND RECOMPACT • -- - - - - - -~ TYPICAL .(,/ (, BENCHING -;7"-,,/- -- ~ - -UNWEA TJ-.ERED BEDROCK OR MATERIAL APPROVED ,,\ :-.,,'<1. ~ BY THE GEOTECHNICAL CONSULTANT~ TRANSITION LOT FILLS GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAIL E I , ,I I I I I I' I I I ,I I I I I I I I RETAINING WALL WALL WA TERPROOFING ~ PER ARCHITECT'S SPECIFICATIONS FINISH GRADE E:::~~l~~~~Ii~@~~!~~~i~~~li~]jIij WALL FOOTING --- SOIL BACKFILl. COMPACTED TO 90 PERCENT RELATIVE COMPACTION BASED ON ASTM 01557 l~l~~~llil~ _1~~ljJ~f~:"--- I ,-::ql ::::=::'5-=:::=:'5-::~~ 6" MI}./ • ::=:::::=:::::=::-.' , .. OVERLAP 1::=:=:::=:=::·' FlL TER FABRIC ENVELOPE • 0 • =:=::.:=-:~~' (MIRAFI 140N OR APPROVED 10 0 0 • 01 :==::.:=~. EQUIVALENT)·· o ____ • • ~ 0 0 ::::::::: . I 1 MIN. I-------~ / " / .. 1> .: •• ~3 4 TO 1-1 2 CLEAN GRAVEL I· . ~I-:-:-:' o • • •• ~ ::::::~ . .---4" (MIN.) DIAMETER PERFORATED t 0 I-:~ PVC PIPE (SCHEDULE 40 OR 6£:. 00 0.' ~'5-:::~ EQUIVALENT) WITH PERFORATIONS o 0 :-:-:-:. ORIENTED DOWN AS DEPICTED I 0 • 0 I ::::::::: MINIMUM 1 PERCENT GRADIENT ~ 0 0 :::::=:=: TO SUITABLE OUTLET L'= -:-:-:-::-.3" MIN. ~l!E!!J~-Al'iil COMPETENT BEDROCK OR MATERIAL AS EVALUATED BY THE GEOTECHNICAL CONSULTANT NOTE: UPON REVIEW BY THE GEOTECHNICAL CONSULTANT, COMPOSITE DRAINAGE PRODUCTS SUCH AS MIRADRAIN OR J-DRAIN MAY BE USED AS AN ALTERNATIVE TO GRAVEL OR CLASS 2 PERMEABLE MATERIAL. INSTALLATION SHOULD BE PERFORMED IN ACCORDANCE WITH MANUFACTURER'S SPECIFICA TIONS. RETAINING WALL DRAINAGE GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAIL F I I I I I I I I I I I I I. I I I I I FILTER FABRIC ACTIVE ZONE .. ~-~tfl---------------/-----..---- f~r -I;~;;;C~~ -~ ----IRETA1NEDI " ~-~~ :\~:{.~ ZONE I ZONE J i---~~.~.=~.g.,:-----------:",-~--(' :~~~~:~}L______________ "" ~~~::l--~-----------/ Ft~til I ----------r----r..;&:i:.?~:~TER FABRIC I ~j~--------~-----~~ DRA~~~~~:::UL-:-r..---!.·.!.· '::,:,::::",.",,: :·!...;.;::,:~~·~~·.~;.l:U~~jt.~ WAll SUBDRAIN \ MIN 0:' BELOW WAll REAR S'IUBDRAIN:' BACKDRAIN TO 70% OF WAUHEIGHT , MIN 12'" BEHtND UNtl"S. 4· (M!N} DI:AMElER PERFORATED PVC PIPE I FOUNDAT~ON sOILsl (SCHEDUlE 40 OR EQULVAlENl)WHH PERFORAlifONS DOWN. SURROUNDED BY NOTES: 1) MATERlALGRADATION AND PLASTICITI REENfORCED ZONE' SIEVE SIZE 1 INCH NO.. 4 NO.4£) NO. 200 %PA$SING 100 20-1!OG (1.60 0-35 FOR WALL HEIGHT < 10 FEET, PLASTICITY INDEX < 20 FOR WALL HBGHT 11) TO 20 FEET, Pu\ST1CtTY iNDEX < 10 FOR TIERED WAllS, USE COMBINED WAll HEIGHTS 1 CU. HIH OF 3t4"GRAIJEl WRAPPED fN FILTER FABRIC (MIRAH 140M OR EQU~VAlENT) OUTl.ET SUB'DRNNS EVERY 10(} FEET, OR CLOSER.. Blf TIGHili1LINE liO SUITABLE PROTECTED OUTLET GRAVE!. DRAINAGE Ell P • StEllE SfZE % PASSI NG 1 INCH 100 31'4 lNCH 75-100 NO.4 0;.60 NO. 40 a-50 NO. 200 0-5 WAll DESIGNER TO REQUEST SITE·SPECIFIC CRITERIA FOR WALL HEIGHT> 20 FEET 2) CONTRACTOR TO USE SOILS WITHIN THE RETAINED AND REINFORCED ZONES THAT MEET THE STRENGTH REQUIREMENTS OF WAll DESIGN. 3} GEOGRID REINFORCEMENT TO BE DESIGNED BY WALL DESIGNER Co.NSIDERING INTERNAL, EXTERNAL, AND COMPOUND STABILITY. 3) GEOGRID TO. BE PRETENSIONED DURING INSTALLATION. 4) IMPROVEMENTS WtTHIN THE ACTIVE ZONE ARE SUSCEPTIBLE TO POST-CONSTRUCTION SETTLEMENT. ANGLE IX 4S+<P/2, WHERE <P IS THE FRICTION ANGLE OF THE MATERIAL IN THE RETAINED ZONE. 5) BACKDRAIN SHo.ULD CONSIST OF J-DRAIN 302 (OR EQUIVALENT) OR 6-INCH THICK DRAINAGE FILL WRAPPED IN FilTER FABRIC. PERCENT COVERAGE OF BACKDRAIN TO BE PER GEOTECHNICAL REVIEW. SEGMENTAL RETAINING WALLS GENERAL EARTHWORK AND GRADING SPECIFICATIONS STANDARD DETAIL G Leighton Consulting, Inc. A LEIGHTON GROUP COMPANY To: Attention: Subject; December 19, 2011 (Revised March 29, 2012) Agua Hedionda Lagoon Foundation clo Hofman Planning & Engineering 3152 Lionshead Avenue Carlsbad, CA 92010 Mr. Eric Munoz Proposal No. 603336-001 Field Percolation Testing Results, Proposed Parking Lot Expansion Area, Agua Hedionda Lagoon Foundation, Carlsbad, California In accordance with your request, Leighton Consulting, Inc. (Leighton) performed field percolation testing within the proposed Parking Lot Expansion area at the Agua Hedionda Lagoon Foundation in Carlsbad, California. Based on review of in-house documents, we understand the area of the proposed improvements is generally underlain by the Santiago Formation with relative a thin layer of surface fill and topsoil. We are currently assuming that the proposed finish grades of the improvements will remain the same (Le., only minor cuts and fills). In summary, we performed three field percolation tests on the site to evaluate the existing on site soils for potential infiltration of storm water. The results of the field percolation tests indicated that the site soils have a percolation rate ranging from approximately 50 to 125 minutes per inch (mpi). The approximate locations of the test and the associated percolation rates are shown on the attached Exhibit A. Note that the designer of the onsite storm water infiltration system should consider the results of field testing, which may vary by 10 percent, and use engineering judgment in developing an appropriate system. 3934 Murphy Canyon Road, Suite 8205 II San Diego, CA 92123-4425 858.569.6914 II Fax 858.292.0771 II www.leightongroup.com ... . 603336-001 The geologic analyses presented in this preliminary geotechnical evaluation have been conducted in general accordance with current practice exercised by geologic consultants performing similar tasks in the project area. No other warranty, expressed or implied, is made regarding the conclusions, recommendations, and opinions presented in this report. Please also note that our evaluation was limited to assessment of the geologic aspects of the project, and did not include evaluation of structural issues, environmental concerns or the presence of hazardous materials. Our conclusions, recommendations and opinions are based on an analysis of the observed site conditions, and our review of the referenced geologic literature and reports. If geologic conditions different from those described in this report are encountered, our office should be notified and additional recommendations, if warranted, will be provided upon request. If you have any questions regarding our results, please contact this office. We appreciate this opportunity to be of service. Respectfully submitted, LEIGHTON CONSULTING, INC. William D. Olson, RCE 45283 Associate Engineer Attachments: Exhibit A -Field Percolation Tests -2- Leighton .... . , , , "i/ '.'/' '.1 ' :/ I I' I 1';1 I' 'I i I I I I I I I I I I I I I I' I Legend FP!"3 Approximate location of field percolation .. test (Leighton, 2012) HA·2 ® Approximate location of hand auger boring /~ o 30 60 Feet Project: 1 0693.001 Eng/Geol: WDOIMDJ Scale: 1 .. = 30' Date: July 2014 Reference: Sheet 3, Precise Grading Plan for Agua Hedlonda Lagoon Foundation overflow Parking Lot, by Hofman Planning & Engineering, 312712014. Author: (mmurphy) Saved as // ""')/ ) .-- ... ~ --- FIELD EXPLORATION MAP Agua Hedionda Lagoon Foundation Parking Lot Expansion Faraday and Cannon Road Carlsbad. California / / ./ " - "-" '" Leighton " ~ , II I!' ! I J' J BAGS HIGH H II SECTION 'Z'-'Z' PLACE ONE BAG-~ BEYOND <t (TYP.) -------..:.....J:~~ TA8I.£ ~' STREET GRAI-FL BAG NO. OF BAG SLOPE (%) INTERVAL LAYERS 0-4% 100' J 4-10% 50' J ~ ~ GRA I£L BAG INTERVAL PER TABLE :.t' BELOW R R/W / STREET GRAVEL BAGGING DETAIL NO SCALE R/W 5' ~I ![ I ~I 5' R/W 2 SAGS T 6' 6~ 0 WEIR WEIR Z o I z ~t z TEMPORARY DESIL TING AT INLETS IN SUMP CONDmON NO SCALE Hofman Planning + Engineering 3156 Uonahead Avenue, Suite 1 CarlebAC!r. CA 92010 (760) ~,,-4100 EDUARDO CADENA TORRES, PE - .~ DATE \'.J'!" ·c I -_-' t..£_~ ~ 0 ~ I. SET POSTS AND EXCAVAlE A 4 BY 4 IN (10 BY 10 CM) TRENCH UPSLOPE FROM AND ALONG THE UNE OF POSTS. ---- ~, / \ ~ -..-" J. A TTACH THE FlL lER FABRIC TO THE K1RE FENCE AND EXlEND IT INro THE TRENCH. '-.. '-.. 2. STAPLE K1RE FENCING ro THE POSTS. 4 IN (10 CM) 4. BACKFILL AND COMPACT THE EXCAVA lEO SOIL. FILlER SILT FENCE NO SCALE M:\Engineering Projects\AHLF\drawing\plan_sets\Precise Grading plan\AHLF -pgp-erosion.dwg 09/25/2014 10:16 ---- -------- -- -- M ... - 8"-10" OIA. (200-25Omm) 120' I LIVE STAKE 1" X 1" STAKE (25 x 25mm) ~ '( ) 10-25~m NOlE: FIBER ROLL INSTALLA nON REQUIRES THE PLACEMENT AND SECURE STAKING OF THE ROLL IN A TRENCH, J"-5" (75-125mm) DEEP, DUG ON CONTOUR. RUNOFF MUST NOT BE ALLOWED TO RUN UNDER OR AROUND ROLL. SPACING DEPENDS ON SOIL TYPE AND SLOPE SlEEPNESS FIBER ROLLS INSTALLATION ON SLOPES NO SCALE : I LEGEND SYMBOL PROP. CONCRETE 4" PCC SIDEWALK. (SEE LANDSCAPE PLANS FOR SCORING PA TTERN & DETAILS) SE-I, SILT FENCE • • • • • • SE -5, FIBER ROLLS «Xxxxmmxum PROP. PERVIOUS PA VERS r~ SE-IO, STORM DRAIN INLET PROTECnON D PROP. PERVIOUS CONCRETE TC-I, STABILIZED CONSTRUCTTON ENTRANCE ~ PROP. DECOMPOSED GRANITE (DG) j ...................... j ...................... .. , .. " .. " .......... . PROP. VEGETA TED SWALE , ( FIBER ROLLS MUST BE PLACED ALONG SLOPE CONTOURS SEDIMENifT. ORGANIC MA TTER, AND NA 1£ SEEDS ARE CAPnJRED BEHIND THE ROLLS. EC-J, STANDARD HYDRAULIC MULCH (SM) TER THAN J" 101~/GlNAL GRADE 12" MIN., UNLESS OTHERK1SE SPEC/FlED BY A SOILS ,ENGINEER SECTION B-B N.T.S. ,.--CJf?USHED AGGREGA TE GREA TER THAN J" BUT SMALLER THAN 6" rCORRUGATED SlEEL PANEL 12" MIN. UNLESS OTHEI~~~ SPECIFIED BY SOILS ENGINEER. SECTION A-A N.T.S. FILTER FABRIC CONSTRUCT SEDIMENT BARRIER AND CHANNEUZE RUNOFF SEDIMENT TRAPPING DEIIICr-"" CORRUGA lED SlEEL PANEL C TEMPORARY PIPE CULVERT AS NEEDED 1-----'------50' MIN. ---------1 OR FOUR TIMES THE CIRCUMFERENCE MATCH EXISTING GRADE NOTE: OF THE LARGEST CONSTRUCnON VEHICLE TIRE, WHICHEVER IS GREA TER PLAN . N.T.S. CONSTRUCTTON SITE ENTRANCE SHALL BE PER CALIFORNIA STORMWA TER BMP HANDBOOK, STANDARD TC-I, MODIFIED AS FOLLOWS: 10' MIN. OR WIDTH AS REQUIRED TO ACCOMODATE ANnCIPATED TRAFFIC, WHICHEVER IS GREATER. 1. METAL SHAKER PLA TES WILL BE REQUIRED A TALL LOCA nONS UNLESS SPECIFICALL Y WAIVED BY THE ENGINEERING INSPECTOR DUE TO SITE CONSTRAINTS. 2. THE ROCK SIZE SHALL BE 2" MINUS. J. A FENCE, BARRICADE OR OTHER DEVICE APPROVED BY THE ENGINEERING INSPECTOR SHALL BE USED TO RESTRICT CONSTRucnON TRAFFIC TO CONSTRue nON ENTRANCE. STABIUZED CONSTRUCTION ENTRANCE/EXIT TC-1 TYPICAL SEcnON NO SCALE I SHEET I CITY OF CARLSBAD I SHEETS I ENGINEERING DEPARTMENT . AGUA HEDIONDA LAGOON FOUNDATION OVERFLOW PARKING LOT EROSION CONTROL PLAN APPROVED: JASON S. GELDERT CIty ENGINEER RCE 63912 OWN BY: EC SE CHKD BY: RVWD BY: EXPIRES 9 30 16 PROJECT NO. SDP 98-15 DAlE DRAWING NO. PREUMINARY FIRST SUBMITIAL SET NOT FOR CONSTRUCTION