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HomeMy WebLinkAboutRP 01-04; STATE STREET COMMERCIAL BLDG; Redevelopment Permits (RP) (3)ENVIRONMENTAL IMPACT ASSESSMENT FORM - PART I (TO BE COMPLETED BY THE APPLICANT) CASE NO: gPOV -OM DATE RECEIVED: s/l^loV (To be completed by staff) BACKGROUND 1. CASENAME: C^s,\gi3&gvV3> \y\UUAC^£. ^COO 2. APPLICANT: UgP^^. t-AtcP-inrzi. 3. ADDRESS AND PHONE NUMBER OF APPLICANT: f. O. Sox I a 4. PROJECT DESCRIPTION: •RI5^A£^/e &(^^tlN6f '^l^^ ^P. GbMp^HSl/^OAL gUO'Cf , iAJ(Th4 3 oNSi-qg f=?<vp>icihif-f space's SUMMARY OF ENVIRONMENTAL FACTORS POTENTIALLY AFFECTED: Please check any of the environmental factors listed below that would be potentially affected by this project. This would be any environmental factor that has at least one impact checked "Potentially Significant Impact," or "Potentially Significant Impact Unless Mitigation Incorporated" in the checklist on the following pages. I I Land Use and Planning I I Population and Housing I I Geological Problems • Water Q Air Quality XI Transportation/Circulation Public Services I I Biological Resources Utilities & Service Systems I I Energy & Mineral Resources Aesthetics I I Hazards Cultural Resources I I Noise Recreation I I Mandatory Findings of Significance Rev. 03/28/96 City of Carlsbad Planning Department INSTRUCTION SHEET FOR FILLING OUT ENVIROIVMENTAL IMPACT ASSESSMENT FORM-PART I This Environmental Impact Assessment (EIA) Form - Part I will be used to determine what type of environmental documentation (i.e., Environmental Impact Report, Mitigated Negative Declaration, Negative Declaration or Exemption) will be required to be prepared for your application, per the Califomia Enyironmental Quality Act (CEQA) and Title 19 qf Carlsbad's Municipal Code. The clarity and accuracy of the information you provide is critical for purposes of quickly determining the specific environmental effects of your project. Recent judicial decisions have held that a "naked checklist,", that is checklist that is merely checked "yes" or "no," is insufficient to comply with the requirements of the Califomia Environmental Quality act. Each "yes" or "no" answer must be accompanied by a written explanation justifying the "yes" or "no" answer. This is especially important when a Negative Declaration is being sought. The more information provided in this forrn," the easier and quicker it will be for staff to complete the Environmental Impact Assessment Form - Part II. 2075 Las Palmas Dr. • Carlsbad, CA 92009-1576 • (619) 438-1161 • FAX (619) 438-0894 ENVIRONMENTAL IMPACTS STATE CEQA GUIDELINES, Chapter 3, Article 5, Section 15063 requires that the City conduct an Environmental Impact Assessment to determine if a project may have a significant effect on the environment. The Environmental Impact Assessment appears in the following pages in the form of a checklist. This checklist identifies any physical, biological and human factors that might be impacted by the proposed project and provides the City with information to use as the basis for deciding whether to prepare an Environmental Impact Report (EIR), Negative Declaration, or to rely on a previously approved EIR or Negative Declaration. • A brief explanation is required for all answers except "No Impact" answers that are adequately supported by an information source cited in the parentheses following each question. A "No Impact" answer is adequately supported if the referenced information sources show that the impact simply does not apply to projects like the one involved. A "No Impacf answer should be explained when there is no source document to refer to, or it is based on project-specific factors as well as general standards. • "Less Than Significant Impact" applies where there is supporting evidence that the potential impact is not adversely significant, and the impact does not exceed adopted general standards and policies. • "Potentially Significant Unless Mitigation Incorporated" applies where the incorporation of mitigation measures has reduced an effect from "Potentially Significant Impact" to a "Less Than Significant Impact." The developer must agree to the mitigation, and the City must describe the mitigation measures, and briefly explain how they reduce the effect to a less than significant level. • "Potentially Significant Impact" is appropriate if there is substantial evidence that an effect is significant. • Based on an "EIA-Part II", if a proposed project could have a potentially significant effect on the environment, but aU potentially significant effects (a) have been analyzed adequately in an earlier EIR or Mitigated Negative Declaration pursuant to applicable standards and (b) have been avoided or mitigated pursuant to that earlier EIR or Mitigated Negative Declaration, including revisions or mitigation measures that are imposed upon the proposed project, and none of the circumstances requiring a supplement to or supplemental EIR are present and all the mitigation measures required by the prior environmental document have been incorporated into this project, then no additional environmental document is required (Prior Compliance). • When "Potentially Significant Impact" is checked the project is not necessarily required to prepare an EIR if the significant effect has been analyzed adequately in an earlier EIR pursuant to applicable standards and the effect will be mitigated, or a "Statement of Overriding Considerations" has been made pursuant to that earlier EIR. • A Negative Declaration may be prepared ifthe City perceives no substantial evidence that the project or any of its aspects may cause a significant effect on the enviromnent. Rev. 03/28/96 • If there are one or more potentially significant effects, the City may avoid preparing an EIR if there are mitigation measures to clearly reduce impacts to less than significant, and those mitigation measures are agreed to by the developer prior to public review. In this case, the appropriate "Potentially Significant Impact Unless Mitigation Incorporated" may be checked and a Mitigated Negative Declaration may be prepared. • An EIR must be prepared if "Potentially Significant Impacf is checked, and including but not limited to the following circumstances: (1) the potentially significant effect has not been discussed or mitigated in an Earlier EIR pursuant to applicable standards, and the developer does not agree to mitigation measures that reduce the impact to less than significant; (2) a "Statement of Overriding Considerations" for the significant impact has not been made pursuant to an earlier EIR; (3) proposed mitigation measures do not reduce the impact to less than significant, or; (4) through the EIA-Part II analysis it is not possible to determine the level of significance for a potentially adverse effect, or determine the effectiveness of a mitigation measure in reducing a potentially significant effect to below a level of significance. A discussion of potential impacts and the proposed mitigation measures appears at the end of the form under DISCUSSION OF ENVIRONMENTAL EVALUATION. Particular attention should be given to discussing mitigation for impacts which would otherwise be determined significant. Rev. 03/28/96 Issues (and Supporting Information Sources): (Supplemental documents may be referred to and attached) I. LAND USE AND PLANNING. Would the proposal:. a) Conflict with general plan designation or zoning? (Source #(s): ( ) b) Conflict with applicable environmental plans or policies adopted by agencies with jurisdiction over the project? ( ) c) Be incompatible with existing land use in the vicinity? ( ) d) Affect agricultural resources or operations (e.g. impacts to soils or farmlands, or impacts from incompatible land uses? ( ) e) Disrupt or divide the physical arrangement of an established community (including a low-income or ' minority community)? ) II. POPULATION AND HOUSING. Would the proposal: a) Cumulatively exceed official regional or local population projections? ( * ) b) Induce substantial growth in an area either directly or , indirectly (e.g. through projects in an undeveloped area or extension of major infrastructure)? ( f ) c) Displace existing housing, especially affordable housing? (>^ ) III. GEOLOGIC PROBLEMS. Would the proposal result in or • expose people to potential impacts involving: a) Fault rupture? (# * ) b) Seismic ground shaking? (4< ) c) Seismic ground failure, including liquefaction? ) d) Seiche, tsunami, or volcanic hazard? ) Landslides or mudflows? ( ) Potentially Significant Impact e) f) g) Erosion, changes in topography or unstable soil conditions from excavation, grading, or fill? ) Subsidence of the land? ( iK -Jc ) h) Expansive soils? (* i< ) i) Unique geologic or physical features? ) 5li* PRfeL . (3rBC>TBcH'L. |5N(4L./ ^i/^W<?i/ (^BC>S(7ICS,|NC IV. WATER. Would the proposal result in: a) Changes in absorption rates, drainage pattems, or the rate and amount of surface runoff? ( ) b) Exposure of people or property to water related hazards such as flooding? ( ) ^MALL, lNni.L. PfsQAGCJ THAT lAJlLL fVT Potentially Significant Unless Mitigation Incorporated Less Than Significan t Impact No Impact • • • • • • • • • / • • • ;< • • • X • • • X • • • • • • X • • • % • • • X • • • X • • • X • • • X • • • X • • • X • • • K • • • X • • • X • • • X Rev. 03/28/96 Issues (and Supporting Information Sources): (Supplemental documents may be referred to and attached) c) Discharge into surface waters or other alteration of surface water quality (e.g. temperature, dissolved oxygen or turbidity)? ( ^ ) d) Changes in the amount of surface water m any water body?(^ ) e) Changes in currents, or the course or direction of water movements? () f) Changes in the quantity of ground waters, either through direct additions or withdrawals, or through interception of an aquifer by cuts or excavations or through substantial loss of groundwater recharge capability? (^ ) g) Altered direction or rate of flow of groundwater? (* ) h) Impacts to groundwater quality? ( ) i) Substantial reduction in the amount of groundwater otherwise available for public water supplies? (Tif ) V. AIR QUALITY. Would the proposal: a) Violate any air quality standard or contribute to an existing or projected air quality violation? ( * ) b) Expose sensitive receptors to pollutants? ( * ) c) Alter air movement, moisture, or temperature, or cause any change in climate? ( *" ) d) Create objectionable odors? ( ) VI. TRANSPORTATION/CIRCULATION. Would the proposal result in: a) Increased vehicle trips or traffic congestion? ( * ) b) Hazards to safety from design features (e.g. sharp curves or dangerous intersections) or incompatible uses (e.g. farm equipment)? (* ) c) Inadequate emergency access or access to nearby uses? (^ ) d) Insufficient parking capacity on-site or off-site? e) Hazards or barriers for pedestrians or bicyclists? •(* ) f) Conflicts with adopted policies supporting altemative transportation (e.g. bus tumouts, bicycle racks)? ( ^ ) g) Rail, waterbome or air traffic impacts? ( ^ ) CfEK^ePATW- ClfcrHlf-l9^MT tNyif^MCNT XWAOJ Potentially Significant Impact • • • • Potentially Significant Unless Mitigation Incorporated • • • • Less Than Significan t Impact No Impact • m • • • • • • X • • • X • • • • • • X • • • X • • • X • • • X • • m • • • • m • • • • • • • • • • • • X • • • >< Rev. 03/28/96 Issues (and Supporting Information Sources): (Supplemental documents may be referred to and attached) VII. BIOLOGICAL RESOURCES. Would the proposal result in impacts to: a) Endangered, threatened or rare species or their habitats (including but not limited to plants, fish, insects, animals, and birds? (*- ) b) Locally designated species (e.g. heritage trees)? ( ) c) Locally designated natural communities (e.g. oak forest, coastal habitat, etc.)? ( ) d) Wetland habitat (e.g. marsh, riparian and vemal pool)? (* ) e) Wildlife dispersal or migration corridors? (* ) Potentially Significant Impact Potentially Significant Unless Mitigation Incorporated Less Than Significan t Impact No Impact • • • • • • X • • • X • • • X • • • >< VIII. ENERGY AND MINERAL RESOURCES. Would the proposal? a) Conflict with adopted energy conservation plans? (* ) b) Use non-renewable resources in a wasteful and inefficient manner? (* ) c) Result in the loss of availability of a known mineral . resource that would be of future value to the region and the residents of the State? (if ) IX. HAZARDS. Would the proposal involve: a) A risk of accidental explosion or release of hazardous substances (including, but not limited to: oil, pesticides, chemicals or radiation)? ( v ) b) Possible interference with an emergency response plan or emergency evacuation plan? (if ) c) The creation of any health hazard or potential health hazards? (^ ) d) Exposure of people to existing soufces of potential health hazards? (^ ) e) Increase fire hazard in areas with flammable brush, grass, or trees? (It ) X. NOISE. Would the proposal result in: a) Increases in existing noise levels? ( *• ) b) Exposure of people to severe noise levels? ' (* ) • • • K • • • K • • • X • • • X • • • X • • • X • • • X • • • X • • • m • • 0 • XI. PUBLIC SERVICES. Would the proposal have an effect upon, or result in a need for new or altered govemment services in any of the following areas: a) Fire protection? { * ) • • m • b) Police protection? ( * ) • • • c) Schools? (•)( ) • • • * 5MyAU, , IMhU- fiaouecT T^T MC?T 6 Rev. 03/28/96 Issues (and Supporting Information Sources): (Supplemental documents may be referred to and attached) d) Maintenance of public facilities, including roads? ( ) e) Other govemmental services? ( ) Potentially Potentially Less Than No Significant Significant Significan Impact Impact Unless t Impact Mitigation Incorporated • • X • • • ?< • XII. UTILITIES AND SERVICES SYSTEMS. Would the proposal result in a need for new systems or supplies, or substantial alterations to the following utilities: a) Power or natural gas? ( ) b) Communications systems? ( ) c) Local or regional water treatment or distribution facilities? ( ) d) Sewer or septic tanks? ( ) e) Storm water drainage? ( ) f) Solid waste disposal? ( g) Local or regional water supplies? ( ) ) XIII. . AESTHETICS. Would the proposal: a) Affect a scenic or vista or scenic highway? ' ( ) b) Have a demonstrate negative aesthetic effect? ( ) c) Create light or glare? ( ) XIV. CULTURAL RESOURCES. Would the proposal: Disturb paieontological resources? ( ) Disturb archaeological resources? ( * ) Affect historical resources? (=K ) Have the potential to cause a physical change which would affect unique ethnic cultural values? ( ) Restrict existing religious or sacred uses within the potential impact area? ( ) -site le wr utrtfeo/ usc/^^ Hi^ioiaJic p.Ea5ai2.ce iNveNTPp-V MST XV. RECREATIONAL. Would the proposal: a) _ Increase the demand for neighborhood or regional parks or other recreational facilities? ( ) b) Affect existing recreational opportunities? ( ) a) b) c) dj • • X • • • X • • • X • • • X • • • X • • • X • • • X • • • • X • • • X • • • X • • • • X • • • X • • • X • • • X • • • X • • n X • • • Rev. 03/28/96 Issues (and Supporting Information Sources): (Supplemental documents may be referred to and attached) XVI. MANDATORY FINDINGS OF SIGNIFICANCE. a) Does the project have the potential to degrade the quality of the environment, substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below self-sustaining levels, threaten to eliminate a plant or animal community, reduce the number or restrict the range of a rare or endangered plant or animal or eliminate important examples of the major periods of Califomia history or prehistory? b) Does the project have impacts that are individually limited, but cumulatively considerable? ("Cumulatively considerable" means that the incremental effects of a project are considerable when viewed in connection with the effects of past projects, the effects of other current projects, and the effects of probable future projects)? c) Does the project have environmental effects which will cause the substantial adverse effects on human beings, either directly or indirectly? Potentially Significant Impact • • • Potentially Significant Unless Mitigation Incorporated • • • Less Than No Significan Impact t Impact m • m • m • XVII. EARLIER ANALYSES. Earlier analyses may be used where, pursuant to the tiering, program EIR, or other CEQA process, one or more effects have been adequately analyzed in an earlier EIR or negative declaration. Section 15063(c)(3)(D). In this case a discussion should identify the following on attached sheets: a) Earlier analyses used. Identify earlier analyses and state where they are available for review. b) Impacts adequately addressed. Identify which effects from the above checklist were within the scope of and adequately analyzed in an earlier document pursuant to applicable legal standards, and state whether such effects were addressed by mitigation measures based on the earlier analysis. c) Mitigation measures. For effects that are "Less than Significant with Mitigation Incorporated," describe the mitigation measures which were incorporated or refined from the earlier document and the extent to which they address site- specific conditions for the project. Rev. 03/28/96 DISCUSSION OF ENVIRONMENTAL EVALUATION Please use this area to discuss any of the environmental factors that were checked "No impact" yet lack any information citations and any factors that were checked "Potentially Significant Impacf or "Potentially Significant Impact Unless Mitigation Incorporated." The City has adopted a "Statement of Overriding Consideration" with regard to air quality and circulation impacts resulting from the normal buildout according to the General Plan. The following sample text is intended to guide your discussion of the impacts to these environmental factors. AIR OUALITY: The implementation of subsequent projects that are consistent with and included in the updated 1994 General Plan will result in increased gas and electric power consumption and vehicle miles traveled. These subsequently result in increases in the emission of carbon monoxide, reactive organic gases, oxides of nitrogen and sulfur, and suspended particulates. These aerosols are the major contributors to air pollution in the City as well as in the San Diego Air Basin. Since the San Diego Air Basin is a "non-attainment basin", any additional air emissions are considered cumulatively significant: therefore, continued development to buildout as proposed in the updated General Plan will have cumulative significant impacts on the air quality of the region. To lessen or minimize the impact on air quality associated with General Plan buildout, a variety of mitigation measures are recommended in the Final Master EIR. These include: 1) provisions for roadway and intersection improvements prior to or concurrent with development; 2) measures to reduce vehicle trips through the implementation of Congestion and Transportation Demand Management; 3) provisions to encourage altemative modes of transportation including mass transit services; 4) conditions to promote energy efficient building and site design; and 5) participation in regional growth management strategies when adopted. The applicable and appropriate General Plan air quality mitigation measures have either been incorporated into the design of the project or are included as conditions of project approval. Operation-related emissions are considered cumulatively significant because the project is located within a "non-attainment basin", therefore, the "Initial Study" checklist is marked "Potentially Significant Impact". This project is consistent with the General Plan, therefore, the preparation of an EIR is not required because the certification of Final Master EIR 93-01, by City Council Resolution No. 94-246, included a "Statement Of Overriding Considerations" for air quality impacts. This "Statement Of Overriding Considerations" applies to all subsequent projects covered by the General Plan's Final Master EIR, including this project, therefore, no further environmental review of air quality impacts is required. This document is available at the Planning Department. CIRCULATION: The implementation of subsequent projects that are consistent with and included in the updated 1994 General Plan will result in increased traffic volumes. Roadway segments will be adequate to accommodate buildout traffic; however, 12 full and 2 partial intersections will be severely impacted by regional through-traffic over which the City has no jurisdictional control. These generally include all freeway interchange areas and major intersections along Carlsbad Boulevard. Even with the implementation of roadway improvements, a number of intersections 9 Rev. 03/28/96 are projected to fail the City's adopted Growth Management performance standards at buildout. To lessen or minimize the impact on circulation associated with General Plan buildout, numerous mitigation measures have been recommended in the Final Master EIR. These include measures to ensure the provision of circulation facilities concurrent with need; 2) provisions to develop alternative modes of transportation such as trails, bicycle routes, additional sidewalks, pedestrian linkages, and commuter rail systems; and 3) participation in regional circulation strategies when adopted. The diversion of regional through-traffic from a failing Interstate or State Highway onto City streets creates impacts that are not within the jurisdiction of the City to control. The applicable and appropriate General Plan circulation mitigation measures have either been incorporated into the design of the project or are included as conditions of project approval. Regional related circulation impacts are considered cumulatively significant because of the failure of intersections at buildout of the General Plan due to regional through-traffic, therefore, the "Initial Study" checklist is marked "Potentially Significant Impact". This project is consistent with the General Plan, therefore, the preparation of an EIR is not required because the recent certification of Final Master EIR 93-01, by City Council Resolution No. 94-246, included a "Statement Of Overriding Considerations" for circulation impacts. This "Statement Of Overriding Considerations" applies to all subsequent projects covered by the General Plan's Master EIR, including this project, therefore, no further environmental review of circulation impacts is required. LIST OF MITIGATTNG MEASURES (IF APPLICABLE) ATTACH MITIGATION MONITORING PROGRAM (IF APPLICABLE) 10 Rev. 03/28/96 Stormwater Pollution Prevention Plan For New (Redeveloped) Commercial Building 2917 State Street, Carlsbad Prepared by David J. McKinley, P.E. Principal Engineer McKinley Engineering RECEIVED If) 200? HOUSIMG&REDEVELOPMENT DEPARTMENT April 24,2002 Revised July 23,2002 L Introduction The current rapid flux in application of stormwater rules can make it difficult to keep perspective. We all affirm that it is important to protect receiving waters from pollution that can be associated with stormwater. At the same time, application of stormwater rules should try to keep focused on meaningful amounts of pollution, that could actually make a difference in the enviroimient. It is a waste of valuable resources to try to eliminate every possible or perceived negative environmental influence, no matter how insignificant. Here we have tried to provide common sense rationale for which stonnwater issues in this small project are significant, and address those. The rapid flux in rule and guideline development also opens up the question of which guidance to use. The City of Carlsbad has a stormwater ordinance that provides legal imderpinnings for city staff to request a stormwater pollution prevention plan. However, Carlsbad's ordinance is not exhaustive, so city staff must rely on other materials as administrative aids. One aid which was provided to us by staff is the Storm Water Pollution Prevention Plan and Monitoring Program Review Sheet. This Sheet was a useful thought trigger to help us key on and address the issues pertinent to this project. However, the Sheet's original purpose was to help administer projects that triggered the need for a General Constmction Activities Storm Water Permit, which applies to projects 5 acres and larger. Hence, many of the items on this Sheet do not apply to the subject project. n. Description of Proiect and Associated Drainage The project in question is a small redevelopment project in the urbanized area of Carlsbad. Several small old buildings will be removed and replaced with a new building. The character of the business district where the project is being built does not include significant unpaved areas. Parking for the project will be off-site on lots operated by the City of Carlsbad. At the front of the building is a sidewalk adjacent to State Street. At the back of the building is a paved alley. The gutter on State Street and the drainage grate in the alley both lead to a storm drain system that discharges to the beach, and on to the Pacific Ocean. The primary receptors for rainfall are the second story roof and balcony areas. These surfaces are about as clean as can be found anywhere in downtown Carlsbad. Rain runmng off of these surfaces will pick up essentially no contaminants. Our plan is to collect this mnoff and pipe it to a discharge point on pavement adjacent to the alley. in. Characterization of Potential Stormwater Pollution For purposes of stormwater, the project is best broken into two phases: the constmction phase, and the post-constmction phase. III.A. Constmction Phase Pollutants Early in the constmction phase, the existing buildings on the site will be demolished down to the underlying soil. This demolition may create building materials particulates, that could contaminate stormwater. The soil exposed by the demolition represents potential stormwater turbidity pollution. After demolition is complete, and the site cleared, new foundation wall and utility trenches wdll be excavated on the site. The piles of soil removed from these excavations are potential sources of stormwater pollution. Following excavation, a new slab foimdation will be poured. The new building wdll then be constmcted. During these constmction activities, a variety of constmction materials will be brought onto the site whose use could result in stormwater pollution. These include powdered and liquid constmction products, sawdust, bits of paper and fibrous debris, sand, surface finishing waste and painting materials. ni.B. Post-Constmction Phase Pollutants The project includes four planters that will contain exposed soil, and will be irrigated. The Carlsbad City Ordinance exempts landscape irrigation from consideration as a source of pollutants of the stormwater conveyance system. (Carlsbad City Ordinance 15.12.055 B.2). However, we do consider the planter soil a potential stormwater pollutant, because it could be mobilized by rainfall. There really is no other significant ongoing source of stormwater pollution associated with the post-constmction phase. The building will have surfaces that urban dust can settle on, but such dust ubiquitous, and is in no way increased by the presence of the building. The outside surfaces of the building, such as the exterior walls and the roof will be of durable materials whose erosion is insignificant as a source of stormwater pollution. The use of the building will be to house a commercial enterprise downstairs, and offices upstairs. In general, offices do not involve processes that generate significant sources of stormwater pollution. Commercial enterprises in the downtown Carlsbad area are most often retail establishments, or restaurants. Such enterprises have some limited potential for stormwater pollution, depending on the processes involved in the specific businesses. This potential will have to be addressed after the occupants are identified, probably during the tenant improvement process. Therefore, the post-constmction phase stormwater pollution control management in this stormwater pollution prevention plan will focus on the planters. IV. Construction Phase Best Management Practices IV.A. Demolition Weather Scheduling Prior to demolition, weather forecasts will be consulted. If rain is predicted, demolition will be postponed until a time when no rain is predicted for at least two days. TV.B. Dailv Clean-Up Thejob specifications shall require that before simdown each workday, the site shall be cleaned of all potential stormwater pollutants. All loose material shall be collected and either removed from the site, or placed in a trash container. The outdoors impervious surfaces on site and adjacent to the site shall be swept clean with a broom. Sweepings shall be deposited in a trash container. IV.C. Trash Containers Trash containers shall be available on site at all times during the constmction phase. All trash containers shall be closed with a lid designed not to blow open due to wind, or shall be kept indoors. Trash containers shall not be overfilled, such that the lids cannot be closed. IV.D. Dirt Pile Management Any excavated dirt awaiting final disposition shall be collected on plastic sheeting of at least 10 mil thickness. Except while being added to, dirt piles also shall be completely covered with plastic sheeting of 10 mil thickness. The cover must be complete enough to prevent stormwater contamination due to any reasonably anticipated rainstorm. The plastic sheeting shall be held in place by durable weights such as blocks, rocks or gravel bags sufficient to stabilize the position of the sheeting against any reasonably anticipated wind. On the up-gradient side of each pile, gravel bags, or an equally effective device, shall be placed to protect the pile from erosion due to stormwater run-on. IV. E. Exposed Soil Management After the old building are demolished and removed, the soil on the lot will be exposed. To prevent erosion due to rainfall, the low side of the lot (the alley side) shall be lined with gravel bags, hay bales, hayrolls or an equally effective erosion control measure. A portion of the erosion control measure may be moved out of the way to facilitate materials transport on the site during dry weather daytime constmction, but shall be replaced to create an unintermpted line before sundown each evening. Use of the erosion control measure shall continue until the foundation slab for the new building is poured. V. Post-Construction Phase Best Management Practices As discussed in section III.B., the only significant post-constmction potential stormwater pollution sources are the four planter areas. V. 1. Planter Drip Irrigation Svstems All planters shall be outfitted with drip irrigation systems controlled by a timer. Drip irrigation is a water-conservative technique that minimizes overspray and over-watering. V.2. BMP First Floor State Street Planters There will be two sections of planter located near each other on the first level on the State Street side of the building. These are to be about 18 inches tall, and set on a concrete base. These planters are set back under the balcony. Hence, they are protected from rainfall, and are unlikely to be sources of stormwater pollution. Even so, there is potential for the planter sections to become saturated from an unusual rainstorm, or an irrigation system failure. Hence, the planters need drains. Each planter will have at least one 2- inch diameter drain in the bottom made of minimum schedule 40 PVC. The drain piping will run undemeath the sidewalk to a hole cored in the curb. To control loss of sediment, the drain in the bottom will be covered with a 12" x 12" square of 1/16" opening stainless steel wire screen. The screen will be covered with a pile of nominal 1/4 inch gravel extending at least 6 inches above and beyond the drain in every direction. V.3. BMP for First Floor Rear Planter There will be a large planter (over 100 square feet) located at the rear of the building adjacent to the alley. This planter shall be located above unpaved soil. To aid infiltration, the soil shall be cultivated with soil amendment to a depth of at least 6 inches. To prevent both run-on and run-off, the planter shall be surrounded by a continuous concrete or brick curb at least 3 1/2 inches tall. V.4. BMP for Second Level Rear Planter There will be a narrow planter upstairs outside the rear upstairs office. This planter will have a closed bottom, and drains. To prevent pollutants which may enter the drains from depositing in the storm drain system, the drains shall be plumbed to discharge to the First Floor Rear Planter below. There any drainage will be confined within that planter's curbing until it can infiltrate. V. 5. BMP for Second Level Front Planters There will be two small planters (approximately 20 square feet each) located at the front upstairs comers of the balcony. They will be closed-bottom planters with drains. Because of the very small size of these planters, and the use of drip irrigation, very little drainage is expected. For this special case, the most practical place to plumb this upstairs front planter drainage is the sanitary sewer. This will provide complete pollution protection for the stormwater system, with very little load on the sanitary system. VI. Summarv and Conclusion This project is simply not one where we expect a major impact on stormwater even if it were managed poorly. The best management practices delineated above can be expected to successfully prevent any significant stormwater pollution from this project. Following is a summarized list of the best management practices for this project Proiect BMP Checklist 1. Demolition Weather Scheduling 2. Daily Clean-Up 3. Trash Containers 4. Dirt Pile Covers 5. Exposed Soil Runoff Protection 6. Planter Drip Irrigation System 7. Specific Measures for Each of Four Planters r I 1*4 I HSMIC CHRISTIANSEN WAY .if. t 1 .IL. 3 I w 4!1 GRAND I 8 i — CO m 4ISfS- 79r AVENUE -S3—5; 1 I CARLSBAD all PROJ6CT SIT6 Oi H m m r X IN ilk -.a 3J 1 - m So ? TP- mar MSOttt VILLAGE DRIVE c "WW * 1 1 NEW COMMERCIAL BUILD1NC3 CARLSBAD VILLAC3E DRIVE PARTNERSHIP 2917 STATE STREET REFERENCE NORTH APPROX. SCALE 1" = 20a alley E?URIN<5 EPEMaJTOM AND CONBTRJCTION 1. DEMOLITION SHALL NOT TAKE PLACE DURIN(5 RAIN. 2. TEMPORARY STOCKPILE OF SOIL SHALL BE COVERED WITH PLASTIC SHEETING WEIGHTED WTH ORAVEL BAGS OR CONCRETE BLOCKS. 3. EXPOSED SOIL SHALL BE RETANED WITH ORAVEL BAGS ALONG THE LOW END OF SITE / ALLEY. A. ALL CONSTRUCTION DEBRIS SHALL BE BE PLACED (DALY) IN TRASH RECEPTACLE AND/OR DUMPSTER WITH A PROPER LID. UJ a O Q. z D D CD 1- UJ z z W o X UJ PROPERTY- LINE Sidewalk WOOD PEDESTRAN BARRIER (3RAVEL BAC5S 7 CONSTRUCTION SITE (3RAVEL BA(3S 7 EiKEiizinnnnc Dm: 37.5' PROPERTY LINE z Q lU S < lij State Street NOT TO SCALE BMP - CONSTRUaiON CARLSBAD VILLAGE DRIVE PARTNERSHIP 2917 STATE STREET RAISED PUANTER W/ DRAIN FILTER -TYPICAL alley ROOF DRAIN UJ Q. O OL Q. V-Z lil ID z Q -J D CQ Ul z 0 ""• ' FROM ABOVE RAJSED CONC. CURB I— ROOF $ FILTERED PLANTER WATER FROM ABOVE DOWN TO PAVINO DOWN TO PAV1N(5 DRAINUNE FROM >| ADJACENT BLD'S. j ROOF WATER 11 r-RAISED PLANTER W/ DRAIN FILTER -TYPICAL z lil lil c Q X < Ui ROOF £ FILTERED PLANTER WATER FROM ABOVE CURB OUTLET SECOND FLOOI^ FIRST FLOOR NOT TO SCALE OMP - BUIIDING CARLSBAD VILLAGE DRIVE PARTNERSHIP 2917 STATE STREET CLEAN GRAVEL 14-" 0 IS" SQ. STAINLESS STEEL 1/8" X1/5" WIRE FABRIC DRAIN ANCHOR FLANGE DRAIN LINE DRAIN BODY PLANTER BAsSE DRAIN FILTER CO NOT TO SCALE PRELIMINARY GEOTECHNICAL EVALUATION 2917 AND 2925 STATE STREET CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA FOR MR. LEOR LAKRITZ C/O ROY A. BLACKFORD, ARCHITECT P.O. BOX 2046 CARLSBAD, CAUFORNIA 92008 W.O. 2968-A-SC JANUARY 9, 2001 Geotechnical • Geologic • Environmental 5741 Palmer Way • Carlsbad, California 92008 • (760)438-3155 • FAX (760) 931-0915 January 9, 2001 W.O. 2968-A-SC Mr. Leor Lakritz c/o Roy A. Blackford, Architect P.O. Box 2046 Carlsbad, California 92008 Attention: Mr. Roy A. Blackford Subject: Preliminary Geotechnical Evaluation, 2917 and 2925 State Street, City of Carlsbad, California, APN# 203-293-10 Dear Sir: In accordance with your request and authorization, GeoSoils, Inc. (GSI) has performed a geotechnical evaluation of the subject site. The purpose of the study was to evaluate the onsite soils and geologic conditions and their effects on the proposed site development from a geotechnical viewpoint. EXECUTIVE SUMMARY Based on our review of the available data (Appendix A), field exploration, laboratory testing, and geologic and engineering analysis, development ofthe property appears to be feasible from a geotechnical viewpoint, provided the recommendations presented in the text of this report are properly incorporated Into design and construction of the project. The most significant elements of this study are summarized below: • All existing colluvium (on the order of 2 to 272 feet thick) is generally loose and potentially compressible, and is not suitable for the support of settlement sensitive Improvements. These materials will require removal and recompaction If settlement sensitive Improvements are proposed within their Influence. Depths of removals are outlined in the conclusions and recommendations section ofthis report. In general, removals will be on the order of 2 to 3 feet across a majority of the site. Removals may extend deeper due to buried utilities. • Owing to the proximity of existing Improvements and the proposed excavations associated with the planned structure, shoring and/or underpinning may be necessary, at least on portions of the site. The actual need for shoring on the north and south sides of the project should be evaluated by the design and/or structural engineer based on the design elevation subgrade of the proposed structure, and proximity of existing improvements, and any surcharge loadings. Vertical excavations should conform to CAL-OSHA and/or OSHA requirements, or should be shored. Temporary cut slopes may be excavated at a 1:1 (horizontal to vertical) gradient, or flatter, based on the available data. If shoring Is necessary, the shoring should be Incorporated into the foundation design by the structural engineer. Consultation with a qualified shoring contractor should be considered. Our laboratory test results indicate that soils onsite are generally very low to low In expansion potential. Sulfate testing indicates that site soils have a negligible exposure to concrete per Table 19-A-4 ofthe 1997 UBC (sample = 0.004 percent by weight). Corrosion testing (ph, resistivity) Indicates that the soils are essentially neutral (pH=7.3) and moderately corrosive to ferrous metals (saturated resistivity= 4,300 ohms-cm). Alternative methods and additional comments should be obtained by a qualified corrosion engineer. Groundwater was not encountered onsite and is generally not anticipated to affect site development, providing that the recommendations contained in this report are Incorporated into final design and construcfion and that prudent surtace and subsurtace drainage practices are incorporated Into the construction plans. Perched groundwater condifions along zones of contrasfing permeabilities should not be precluded fi'om occurring In the future due to site Irrigafion, poor drainage condifions, or damaged ufilifies. Should perched groundwater condifions develop, this office could assess the affected area(s) and provide the appropriate recommendations to mitigate the observed groundwater condifions. Our evaluation Indicates there are no known active faults crossing the site. Our evaluafion also indicates that the site has a very low potenfial for liquefacfion. Therefore, no recommendations for mitigation are deemed necessary. The seismic design parameters presented herein should be considered during project planning and design. Convenfional foundafion systems ufilizing slab-on-grade may be used onsite. The geotechnical design parameters presented herein should be Incorporated into project planning, design, and construcfion by the project structural engineer and architect. Mr. Leor Lakritz W.O. 2968-A-SC Rle:e:\wp7\2900\2968a.pge Page Two GeoSoils, Ine. The opportunity to be of service is greafiy appreciated. If you have any quesfions concerning this report or If we may be of further assistance, please do not hesitate to contact any ofthe undersigned. Respectfully submitted, GeoSoils, Inc. m voss Staff Geologist Reviewed by: iavid W. Sl<» Civil Engineei^g%te4^§'ik BV/RGC/JPF/DW^yrfe Robert G. Crisman ^ Engineering Geologls^^6|f^^|l3 lO Distribufion: (4) Addressee Mr. Leor Lakritz File:e:\wp7\2900\2968a.pge W.O. 2968-A-SC Page Tiiree TABLE OF CONTENTS SCOPE OF SERVICES 1 SITE CONDITIONS/PROPOSED DEVELOPMENT 1 FIELD STUDIES 3 REGIONAL GEOLOGY 3 EARTH MATERIALS 3 Colluvium (Not mapped) 3 Terrace Deposits (Map Symbol-Qt) 5 FAULTING AND REGIONAL SEISMICITY 5 Faulfing 5 Seismicity 7 Seismic Shaking Parameters 7 Seismic Hazards 8 LABORATORY TESTING 8 General 8 Laboratory Standard 8 Expansion Potential .9 Direct Shear Test 9 Corrosion/Sulfate Tesfing 9 Sieve Analysis 9 CONCLUSIONS 10 EARTHWORK CONSTRUCTION RECOMMENDATIONS 10 General 10 Site Preparafion 10 Demolifion/Grubbing 10 Removals (Unsuitable Surficial Materials) 11 Fill Placement 11 Overexcavafion 11 FOUNDATION RECOMMENDATIONS 11 General 11 Preliminary Foundation Design 12 Bearing Value 12 Lateral Pressure 12 Construcfion 12 Expansion Classification - Very Low to Low (El 0 to 50) 13 GeoSoils, Ine. CONVENTIONAL RETAINING WALLS 14 General 14 Restrained Walls 14 Canfilevered Walls 15 Wall Backfill and Drainage 15 DEVELOPMENT CRITERIA 16 Landscape Maintenance and Planting 16 Addifional Site Improvements 16 Trenching 16 Drainage 17 Ufility Trench Backfill 17 PLAN REVIEW 17 LIMITATIONS 18 FIGURES: Figure 1 - Site Locafion Map 2 Figure 2 - Boring Locafion Map 4 Figure 3 - California Fault Map 6 ATTACHMENTS: Appendix A - References Rear of Text Appendix B - Boring Logs Rear of Text Appendix C - Laboratory Data Rear of Text Appendix D - General Earthwork and Grading Guidelines Rear of Text Mr. Leor Lakritz Table of Contents Rle:e:\wp7\2900\2968a.pge Page ii GeoSoilSf Ine. PRELIMINARY GEOTECHNICAL EVALUATION 2917 AND 2925 STATE STREET CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA SCOPE OF SERVICES The scope of our services has included the following: 1. Review of readily available soils and geologic data (Appendix A), including the previous geologic report for the site. 2. Subsurtace explorafion consisfing of 3 hand auger boring excavafions to determine the soil/bedrock profiles, obtain relafively undisturbed and bulk samples of representative materials, and delineate earth material parameters for the proposed development (Appendix B). 3. Laboratory tesfing of representative soil samples collected during our subsurface explorafion program (Appendix C). 4. General areal seismicity evaluafion. 5. Appropriate engineering and geologic analysis of data collected and preparafion of this report. SITE CONDITIONS/PROPOSED DEVELOPMENT The site consists of a rectangular shaped parcel located on the west side of State Street In Carlsbad, California (Figure 1). The exisfing site Is bounded by retail structures on the north and south, and an alleyway on the west. Exisfing structures onsite consist of a retail structure fi'onfing State Street, a small residenfial duplex structure fi-onfing the alley and a single-story structure located between the two. The site drainage Is generally to the northwest. According to a 1968 (photorevised 1975) San Luis Rey, California Topographic Map, the subject site Is approximately 46 feet above Mean Sea Level (MSL). The proposed site development will consist of removing the exisfing structures and preparing the pad for the construcfion of a mulfi-story office building, it Is also our understanding that cut and flll grading techniques would be ufilized to create design grades for the proposed mulfi-story building. It Is anficipated that the development will consist of a multi-story structure with slab-on-grade floors and confinuous foofings, ufilizing wood-frame construcfion. Building loads are assumed to be typical for this type of relafively light construcfion. The need for Import soils is unknown. GeoSoilSf Ine. ft3»-10' Ktt) *r vJrHifehSch* '\ 4c Base Map: San Luis Rey Quadrangle, Caiifornia—San Diego Co., 7.5 Minute Series (Topographic), 1968 (photo revised 1975), by USGS, 1"=2000' N 2000 Scale 4000 Feet W.O. 2968-A-SC SITE LOCATION MAP Figure 1 FIELD STUDIES Field work conducted during our evaluafion ofthe property consisted of excavafing 3 hand auger borings within the lot to evaluate near surface soil and geologic conditions. The borings were logged by a geologist from our firm. Representative bulk and in-place samples were taken for appropriate laboratory tesfing. Logs of the borings are presented in Appendix B. The approximate locafions of the boring logs are shown on Figure 2. REGIONAL GEOLOGY The subject property is located within a prominent natural geomorphic province in southwestern California known as the Peninsular Ranges. It Is characterized by steep, elongated mountain ranges and valleys that trend northwesterly. The mountain ranges are underlain by basement rocks consisting of pre-Cretaceous metasedimentary rocks, Jurassic metavolcanic rocks, and Cretaceous plutonic rocks of the southern California batholith. In the San Dlego region, deposifion occurred during the Cretaceous period and Cenozoic era In the confinental margin of a forearc basin. Sediments, derived from Cretaceous-age plutonic rocks and Jurassic-age volcanic rocks, were deposited into the narrow, steep, coastal plain and confinental margin ofthe basin. These rocks have been uplifted, eroded and deeply incised. During early Pleistocene fime, a broad coastal plain was developed from the deposifion of marine terrace deposits. During mid to late Pleistocene fime, this plain was uplifted, eroded and incised. Alluvial deposits have since filled the lower valleys, and young marine sediments are currently being deposited/eroded within coastal and beach areas. EARTH MATERIALS Earth materials encountered on the site are shown on Figure 2. The materials consist of colluvium and terrace deposits. Colluvium (not mapped) The site colluvium generally consist of a brown to dark brown, dry to moist, loose, silty sand. Thickness of the material is approximately 2 to 2>h feet. Colluvium at the subject site Is considered potenfially compressible In Its present state. Accordingly, these soils are considered unsuitable for support of addifional fill and/or settlement sensifive improvements in their exisfing state. Mr. Leor Lakritz W.O. 2968-A-SC 2917 and 2925 State Street, Carlsbad January 9, 2001 Rle:e:\wp7\2900\2968a.pge Page 3 GeoSoils, Ine. SIDEWALK I I 373" EXISTING RETAIL B30± d o «B-2 EX1ST1NC5 B-1 Qt I Qt IT EXISTINO DUPLEX .5, l\ nr:.:T:zr: jrp.-..z\- 373 PROP.LINE ALLEY ALL EXISTINO BUILDINC3S TO BE REMOVED OUTLINE OF PROPOSED 2 STORY BUILDINO LEGEND Qt Quaternary Terrace deposits ^ B-3 Approximate location of exploratory boring Base map provided by client mn LOS ANGELES CO. RIVERSIDE CO. ORANGE CO. SAN DIEGO CO. BORING LOCATION MAP Rgure 2 W.O. 2968-A-SC DATE 12/00 SCALE none Terrace Deposits (Map Symbol - Qt) Quaternary-age terrace deposits underlies the enfire site at depth. As encountered, the terrace deposits generally consist of brown, silty sands, and are medium dense. Due to the relatively loose and weathered condition ofthe upper ±1 foot, these materials should be removed, moisture condifioned, and recompacted and/or processed in place, should settlement-sensitive improvements be proposed within their influence. This unit typically has a low to medium expansion potenfial. FAULTING AND REGIONAL SEISMICITY Faulting The site is situated in a region of active as well as potentially-active faults. Our review indicates that there are no known active faults crossing the site within the areas proposed for development (Jennings, 1994), and the site is not within an Earthquake Fault Zone (Hart and Bryant, 1997). There are a number of faults in the southern California area that are considered acfive and would have an effect on the site in the form of ground shaking, should they be the source of an earthquake (Figure 3). These faults include-but are not limited to~the San Andreas fault, the San Jacinto fault, the Elsinore fault, the Coronado Bank fault zone, and the Newport-Inglewood - Rose Canyon fault zone. The possibility of ground accelerafion or shaking at the site may be considered as approximately similar to the southern California region as a whole. The following table lists the major faults and fault zones in southern California that could have a signiflcant effect on the site should they experience signiflcant activity. ABBREVIATED FAULT NAME APPROXIMATE DISTANCE MILES (KM) Coronado Bank-Agua Blanca 21(33) Elsinore 24 (39) La Nacion 25(40) Newport-lnglewood-Offsliore 7(12) Rose Canyon 4(6) San Diego Trougii-Bahia Sol. 30 (48) Mr. Leor Lakritz 2917 and 2925 State Street, Carlsbad File:e:\wp7\2900\2968a.pge GeoSoils, Ine. W.O. 2968-A-SC January 9, 2001 Page 5 SAN FRANCISCO SITE LOCATION Latitude - 33.1596 N Longitude - 117.3491 W UKRITZ W.O. 2968-A-SC CALIFORNIA FAULT Figure 3 GeoSoils, Ine. Seismicity The accelerafion-attenuafion relafions of Joyner and Boore (1982), Campbell and Bozorgnia (1994), and Sadigh and others (1987) have been incorporated into EQFAULT (Blake, 1997). For this study, peak horizontal ground accelerafions anficipated at the site were determined based on the random mean and mean plus 1 sigma attenuafion curves developed by Joyner and Boore (1982), Campbell and Bozorgnia (1994), and Sadigh and others (1989). These accelerafion-attenuafion relafions have been incorporated in EQFAULT, a computer program by Thomas F. Blake (1997), which performs determinisfic seismic hazard analyses using up to 150 digifized California faults as earthquake sources. The program esfimates the closest distance between each fault and a user-specified file. If a fault is found to be within a user-selected radius, the program esfimates peak horizontal ground accelerafion that may occur at the site from the upper bound ("maximum credible") and "maximum probable" earthquakes on that fault. Site accelerafion, as a percentage ofthe acceleration of gravity (g). Is computed by any of the 14 user-selected accelerafion-attenuation relafions that are contained in EQFAULT. Based on the above, peak horizontal ground accelerafions from an upper bound (maximum credible) earthquake may be on the order of 0.66 g to 0.80 g, and maximum probable event may be on the order of 0.45 g to 0.47 g, assuming upper bound (maximum credible) and maximum probable event of a magnitude about 6.9, on the Rose Canyon fault zone, located approximately 4 miles from the subject site. Seismic Shaking Parameters Based on the site condifions. Chapter 16 of the Uniform Building Code (Internafional Conference of Building Officials, 1997), the following seismic parameters are provided. Seismic zone (per Figure 16-2*) 4 Seismic Zone Factor (per Table 16-1*) 0.40 Soil Profile Type (per Table 16-J*) SD Seismic Coefficient C, (per Table 16-Q*) 0.44 Na Seismic Coefficient C^ (per Table 16-R*) 0.64 N^ Near Source Factor N, (per Table 16-S*) 1.0 Near Source Factor N^ (per Table 16-T*) 1.1 Seismic Source Type (per Table 16-U*) B Distance to Seismic Source 4.0 mi. (6.4 km) Upper Bound Earthqual<e 6.9 * Figure and table references from Ciiapter 16 of tlie Uniform Building Code (1997). Mr. Leor lakritz 2917 and 2925 State Street, Carlsbad Flle:e:\wp7\2900\2968a.pge W.O. 2968-A-SC January 9, 2001 Page 7 GeoSoils, Ine. Seismic Hazards The following list includes other seismic related hazards that have been considered during our evaluafion ofthe site. The hazards listed are considered negligible and/or completely mitigated as a result of site location, soil characterisfics and typical site development procedures: Liquefacfion Tsunami Dynamic Settlement Surface Fault Rupture Ground Lurching or Shallow Ground Rupture It is important to keep in perspecfive that in the event of a maximum probable or credible earthquake occurring on any of the nearby major faults, strong ground shaking would occur in the subject site's general area. Potential damage to any structure(s) would likely be greatest from the vibrafions and impelling force caused by the inertia of a structure's mass, than from those induced by the hazards considered above. This potenfial would be no greater than that for other exisfing structures and improvements In the immediate vicinity. LABORATORY TESTING General Laboratory tests were performed on representafive samples of the onsite earth materials in order to evaluate their physical characteristics. The test procedures used and results obtained are presented below. Laboratory Standard The maximum dry density and opfimum moisture content was determined forthe major soil type encountered in the trenches. The laboratory standard used was ASTM D-1557. The moisture-density relafionship obtained for this soil is shown below: SOIL TYPE BORING OR TEST PIT AND DEPTH (ft.) MAXIMUM DRY DENSITY (pcf) OPTIMUM MOISTURE CONTENT (%) Silty SAND, strong brown B-1 @ 0-5 127.5 12.0 Silty SAND, strong brown B-2@ 0-5 131.0 9.0 Mr. Leor Lakritz 2917 and 2925 State Street, Carlsbad File:e:\wp7\2900\2968a.pge GeoSoils, Ine. W.O. 2968-A-SC January 9, 2001 Page 8 Expansion Potential Expansion testing was performed on a representafive sample of site soil in accordance with UBC Standard 18-2. The results of expansion testing are presented in the following table. LOCATION EXPANSION INDEX EXPANSION POTENTIAL B-2@ 0'-5' <5 Very Low Direct Shear Test Shear testing was performed in general accordance with ASTM test method D-3080 in a direct shear machine ofthe strain control type. The shear test results are presented below: Sample Location Primary Residual Sample Location Cohesion (psf) Friction Angle (Degrees) Cohesion (psf) Fricfion Angle (Degrees) B-1 (Remolded composite sample) 368 31 457 27 Corrosion/Sulfate Testing Sulfate tesfing Indicates that site soils have a negligible exposure to concrete per Table 19- A-4 of the 1997 UBC (water extractable sulfate = 0.004 percent by weight). Corrosion tesfing (pH, resistivity) indicates that soils are neutral (pH = 7.3) and moderately corrosive (saturated resistivity = 4,300 ohms-cm) to ferrous metals. Sieve Analysis Sample gradafion for various representative samples was determined in general accordance with ASTM test method D-422. Test results are presented as Plates C-1 in Appendix C. Mr. Leor Lakritz 2917 and 2925 State Street, Carlsbad File:e:\wp7\2900\2968a.pge W.O. 2968-A-SC January 9, 2001 Page 9 GeoSoils, Inc. CONCLUSIONS Based upon our site reconnaissance, test results, it is our opinion that the subject site appears suitable for the proposed office building development. The following recommendafions should be incorporated into the construcfion details. EARTHWORK CONSTRUCTION RECOMMENDATIONS General All grading should conform to the guidelines presented in Appendix Chapter A33 of the Uniform Building Code, the requirements of the City of Carlsbad, and the Grading Guidelines presented in Appendix D, except where specifically superseded in the text of this report. Prior to grading, a GSI representative should be present at the preconstruction meefing to provide addifional grading guidelines, if needed, and review the earthwork schedule. During earthwork construcfion all site preparation and the general grading procedures of the contractor should be observed and the fill selectively tested by a representative(s) of GSI. If unusual or unexpected conditions are exposed in the field, they should be reviewed by this office and if wan'anted, modifled and/or additional recommendations will be offered. All applicable requirements of local and national construction and general industry safety orders, the Occupafional Safety and Health Act, and the Construcfion Safety Act should be met. Site Preparation Debris, vegetafion and other deleterious material should be removed from the building area prior to the start of grading. Sloping areas to receive flll should be properly benched in accordance with current industry standards of practice and guidelines specifled in the Uniform Building Code. Demolition/Grubbing 1. Any exisfing subsurface structures, major vegetafion, and any miscellaneous debris should be removed from the areas of proposed grading. 2. The project soils engineer should be notified of any previous foundafion, irrigafion lines, cesspools, or other subsurface structures that are uncovered during the recommended removals, so that appropriate remedial recommendafions can be provided. Mr. Leor Lakritz W.O. 2968-A-SC 2917 and 2925 State Street, Carlsbad January 9, 2001 File:e:\wp7\2900\2968a.pge Page 10 GeoSoils, Ine. Removals (Unsuitable Surficial Materials) Due to the relatively loose/soft condifion of colluvium and weathered terrace deposits, these materials should be removed and recompacted in areas proposed for settlement sensifive structures or areas to receive compacted flll. At this time, removal depths on the order of 2 to 3 feet should be anficipated, however, locally deeper removals may be necessary, specially if buried utilifies are encountered. Removals should be completed below a 1:1 projecfion down and away from the edge of any settlement sensitive structure and/or limit of proposed fill. Once removals are completed, the exposed bottom should be reprocessed and compacted. Fill Placement Subsequent to ground preparafion, onsite soils may be placed in thin (6±inch) lifts, cleaned of vegetafion and debris, brought to a least opfimum moisture content, and compacted to achieve a minimum relafive compacfion of 90 percent. If soil Importafion is planned, a sample ofthe soil Import should be evaluated by this offlce prior to importing, in order to assure compafibility with the onsite site soils and the recommendafions presented in this report. Import soils (if any) for a fill cap should be low expansive (E.I. less than 50). The use of subdrains at the bottom of the flll cap may be necessary, and subsequenfiy recommended based on compafibility with onsite soils. Overexcavation In order to provide for the uniform support of the structure, a minimum 3-foot thick flll blanket is recommended. Any cut portion of the pad for the building should be over excavated a minimum 3 feet below flnish pad grade. Areas with planned flils less than 3 feet should be over excavated in order to provide the minimum flll thickness. FOUNDATION RECOMMENDATIONS General In the event that the informafion concerning the proposed development plan is not con'ect, or any changes in the design, location or loading condifions ofthe proposed structure are made, the conclusions and recommendafions contained in this report shall not be considered valid unless the changes are reviewed and conclusions of this report are modified or approved in wrifing by this office. It is our understanding that slab-on-grade construcfion is desired for the proposed development. The informafion and recommendafions presented in this secfion are not meant to supersede design by the project structural engineer. Upon request, GSI could provide additional input/consultafion regarding soil parameters, as related to foundafion design. Mr. Leor Lakritz W.O. 2968-A-SC 2917 and 2925 State Street, Carlsbad January 9, 2001 File:e:\wp7\2900\2968a.pge Page 11 GeoSoils, Ine. Preliminary Foundation Design Our review, field work, and laboratory tesfing indicates that onsite soils have a very low to low expansion potenfial. Preliminary recommendafions for foundation design and construction are presented below. Final foundafion recommendafions should be provided at the conclusion of grading, and based on laboratory tesfing of fill or natural materials exposed at finish grade. Bearing Value 1. The foundation systems should be designed and constructed in accordance with guidelines presented in the latest edifion of the Uniform Building Code. 2. An allowable bearing value of 1500 pounds per square foot may be used for the design of confinuous foofings at least 12 inches wide and 12 inches deep, and column foofings at least 24 inches square and 24 inches deep, connected by a grade beam in at least one direcfion. This value may be increased by 20 percent for each addifional 12 inches in depth to a maximum of 2500 pounds per square foot. No increase in bearing value is recommended for increased foofing width. Lateral Pressure 1. For lateral sliding resistance, a 0.35 coefficient of fricfion may be ufilized for a concrete to soil contact when mulfiplied by the dead load. 2. Passive earth pressure may be computed as an equivalent fluid having a density of 300 pounds per cubic foot with a maximum earth pressure of 2500 pounds per square foot. 3. When combining passive pressure and fricfional resistance, the passive pressure component should be reduced by one-third. Construction The following foundafion construcfion recommendafions are presented as a minimum criteria from a soils engineering standpoint. The onsite soils expansion potenfials are generally in the very low to low range (expansion index 0 to 50). Due to potenfial property line restricfions in the vicinity of adjacent structures, footings in these areas may need to be deepened to penetrate any near-surface colluvial soil and embedded into the underlying terrace deposits. Should this become necessary, recommendafions for mitigation of differential settlement of the slab should be obtained from the structural engineer. Mr. Leor Lakritz W.O. 2968-A-SC 2917 and 2925 State Street, Carisbad January 9, 2001 Flle:e:\wp7\2900\2968a.pge Page 12 GeoSoils, Ine. Recommendafions by the project's design-structural engineer or architect, which may exceed the soils engineer's recommendafions, should take precedence over the following minimum requirements. Final foundation design will be provided based on the expansion potenfial ofthe near surface soils encountered during grading. Expansion Classification - Very Low to Low (El 0 to 50) 1. Convenfional confinuous foofings should be founded at a minimum depth of 12 inches below the lowest adjacent ground surface for one-story fioor loads and 18 inches below the lowest adjacent ground surface for two-story floor loads. Interior foofings may be founded at a depth of 12 inches below the lowest adjacent ground surface. Foofings for one-story floor loads should have a minimum width of 12 Inches, and foofings for two-story floor loads should have a minimum width of 15 inches. All foofings should have one No. 4 reinforcing bar placed at the top and one No. 4 reinforcing bar placed at the bottom ofthe foofing. Isolated interior or exterior piers and columns should be founded at a minimum depth of 24 inches below the lowest adjacent ground surface. 2. A grade beam, reinforced as above, and at least 12 inches square, should be provided across the garage entrances. The base of the reinforced grade beam should be at the same elevafion as the adjoining foofings. 3. Concrete slabs in building and garage areas should be undertain with a vapor barrier consisfing of a minimum of 6-mil, polyvinyl-chloride membrane with all laps sealed. This membrane should be covered with a minimum of 2 inches of sand to aid in uniform curing of the concrete. 4. Concrete slabs, including garage slabs, should have a minimum thickness of 4 inches and should be reinforced with No. 3 reinforcement bars placed on 18-inch centers, in two horizontally perpendicular direcfions (i.e., long axis and short axis). Equivalent reinforcement may be used if necessary. All slab reinforcement should be supported to ensure proper mid-slab height poslfioning during placement of the concrete. "Hooking" is not an acceptable method of poslfioning the reinforcing wire. 5. Garage slabs should be poured separately from the building foofings and be quartered with expansion joints or saw cuts. A positive separation from the footings should be maintained with expansion joint material to permit relative movement. 6. Pre-moistening of slab areas is recommended for these soil condifions; the Mr. Leor Lakritz W.O. 2968-A-SC 2917 and 2925 State Street, Carlsbad January 9, 2001 File:e:\wp7\2900\2968a.pge Page 13 GeoSoils, Inc. moisture content of the subgrade soils should be equal to or greater than opfimum moisture to a depth of 12 inches below the adjacent ground grade in the slab areas, and verified by this office within 72 hours of the vapor barrier placement. 7. Soils generated from footing excavafions to be used onsite should be compacted to a minimum relafive compacfion 90 percent of the laboratory standard, whether it is to be placed inside the foundafion perimeter or in the yard/right-of-way areas. This material must not alter posifive drainage patterns that direct drainage away from the structural areas and toward the street. 8. As an alternative, an engineered post-tension foundafion system may be used. CONVENTIONAL RETAINING WALL RECOMMENDATIONS General Foundafions may be designed using parameters provided in the "Design" secfion of Foundafion Recommendafions presented herein. Wall secfions should adhere to the County of San Diego guidelines. All wall designs should be reviewed by a qualified structural engineer for structural capacity, overturning and stability. The design parameters provided assume that onsite or equivalent low expansive soils are used to backfill retaining walls. If expansive soils are used to backfill the proposed walls within this wedge. Increased acfive and at-rest earth pressures will need to be utilized for retaining wall design. Heavy compacfion equipment should not be used above a 1:1 projecfion up and away from the bottom of any wall. The following recommendafions are not meant to apply to specialty walls (cribwalls, loffel, earthstone, etc.). Recommendafions for specialty walls will be more onerous than those provided herein, and can be provided upon request. Some movement of the walls constructed should be anficipated as soil strength parameters are mobilized. This movement could cause some cracking dependent upon the materials used to construct the wall. To reduce wall cracking due to settlement, walls should be internally grouted and/or reinforced with steel. Restrained Walls Any retaining walls that will be restrained prior to placing and compacfing backfill material or that have re-entrant or male corners, should be designed for an at-rest equivalent fluid pressures of 65 pcf for nafive soil or 38 pcf for gravel backfill, plus any applicable surcharge loading. For areas of male or re-entrant corners, the restrained wall design should extend a minimum distance of twice the height of the wall laterally from the corner. Mr. Leor Lakritz W.O. 2968-A-SC 2917 and 2925 State Street, Carlsbad January 9, 2001 Flle:e:\wp7\2900\2968a.pge Page 14 GeoSoils, Inc. Building walls below grade, should be water-proofed or damp-proofed, depending on the degree of moisture protecfion desired. Refer to the following secfion for preliminary recommendafions from surcharge loads. Cantilevered Walls These recommendafions are for cantilevered retaining walls up to fifteen (15) feet high. Active earth pressure may be used for retaining wall design, provided the top of the wall is not restrained from minor deflecfions. An empirical equivalent fluid pressure (EFP) approach may be used to compute the horizontal pressure against the wall. Appropriate fluid unit weights are provided for specific slope gradients ofthe retained material. These do not include other superimposed loading condifions such as traffic, structures, seismic events or adverse geologic condifions. SURFACE SLOPE OF EQUIVALENT SELECT RETAINED MATERIAL FLUID WEIGHT MATERIAL HORIZONTAL TO VERTICAL P.C.F. (Native soiU P.C.F. (Graven Level 45 33 2 to 1 60 ~ The equivalent fiuid density should be increased to 65 pounds per cubic foot for level backfill at the angle point of the wall (corner or male re-entrant) and extended a minimum lateral distance of 2H (two fimes the wall height) on either side of the corner. Wall Backfill and Drainage All retaining walls should be provided with an adequate gravel and pipe backdrain and outlet system (a minimum 2 outlets per wall), to prevent buildup of hydrostafic pressures and be designed in accordance with minimum standards presented herein. Pipe should consist of schedule 40 perforated PVC pipe. Gravel used in the backdrain systems should be a minimum of 3 cubic feet per lineal foot of % to iy2-inch clean crushed rock encapsulated in filter fabric (Mirafi 140 or equivalent). Perforafions in pipe should face down. The surface of the backfill should be sealed by pavement or the top 18 inches compacted to 90 percent relative compacfion with native soil. Proper surface drainage should also be provided. As an alternative to gravel backdrains, panel drains (Miradrain 6000, Tensar, etc.) may be used. Panel drains should be installed per manufacturers guidelines. Regardless of the backdrain used, walls should be water proofed where they would impact living areas or where staining would be objecfionable. Mr. Leor Lakritz 2917 and 2925 State Street, Carlsbad File:e:\wp7\2900\2968a.pge W.O. 2968-A-SC January 9, 2001 Page 15 GeoSoils, Inc. Retaining Wall Footing Transitions Site walls are anficipated to be founded on foofings designed in accordance with the recommendafions in this report. Wall foofings may transifion from formafional bedrock to select fill. If this condifion is present the civil designer may specify either: a) If transitions from rock fill to select fill transect the wall footing alignment at an angle of less than 45 degrees (plan view), then the designer should perform a minimum 2-foot overexcavafion for a distance of two fimes the height of the wall and increase overexcavation until such transifion is between 45 and 90 degrees to the wall alignment. b) Increase of the amount of reinforcing steel and wall detailing (i.e., expansion joints or crack control joints) such that an angular distortion of 1/360 for a distance of 2H (where H=wall height in feet) on either side of the transifion may be accommodated. Expansion joints should be sealed with a flexible, non-shrink grout. c) Embed the foofings enfirely into a homogeneous fill. DEVELOPMENT CRITERIA Landscape Maintenance and Planting Water has been shown to weaken the inherent strength of soil and slope stability is significantly reduced by overiy wet condifions. Positive surface drainage away from graded slopes should be maintained and only the amount of irrigation necessary to sustain plant life should be provided for planted slopes. Overwatering should be avoided. Graded slopes constructed within and ufilizing onsite materials would be erosive. Eroded debris may be minimized and surficial slope stability enhanced by establishing and maintaining a suitable vegetafion cover soon after construcfion. Plants selected for landscaping should be light weight, deep rooted types which require little water and are capable of surviving the prevailing climate. Compacfion to the face of fill slopes would tend to minimize short term erosion unfil vegetafion is established. In order to minimize erosion on a slope face, an erosion control fabric (i.e. jute matting) should be considered. From a geotechnical standpoint leaching is not recommended for establishing landscaping. If the surface soils area processed for the purpose of adding amendments they should be recompacted to 90 percent relative compacfion. Mr. Leor Lakritz W.O. 2968-A-SC 2917 and 2925 State Street. Carlsbad January 9, 2001 File:e:\wp7\2900\2968a.pge Page 16 GeoSoils, Inc. Additional Site Improvements Recommendafions for addifional grading, exterior concrete flatwork design and construction, including driveways, can be provided upon request. If in the future, any addifional improvements are planned for the site, recommendafions concerning the geological or geotechnical aspects of design and construction of said improvements could be provided upon request. Trenching All foofing trench excavations for structures and walls should be observed and approved by a representative of this office prior to placing reinforcement. Footing trench spoil and any excess soils generated from ufility trench excavafions should be compacted to a minimum relafive compacfion of 90 percent if not removed from the site. All excavations should be observed by one of our representafives and conform to CAL-OSHA and local safety codes. GSI does not consult in the area of safety engineers. In addifion, the potential for encountering hard spots during foofing and ufility trench excavafions should be anficipated. If these concrefions are encountered within the proposed foofing trench, they should be removed, which could produce larger excavated areas within the foofing or ufility trenches. Drainage Posifive site drainage should be maintained at all fimes. Drainage should not fiow uncontrolled down any descending slope. Water should be directed away from foundafions and not allowed to pond and/or seep Into the ground. Pad drainage should be directed toward the street or other approved area. Roof gutters and down spouts should be considered to control roof drainage. Down spouts should outlet a minimum of 5 feet from the proposed structure or into a subsurface drainage system. We would recommend that any proposed open bottom planters adjacent to proposed structures be eliminated for a minimum distance of 10 feet. As an alternafive, closed bottom type planters could be utilized. An outiet placed in the bottom ofthe planter, could be instailed to direct drainage away from structures or any exterior concrete flatwork. Utility Trench Backfill 1. All utility trench backfill in structural areas, slopes, and beneath hardscape features should be broughtto near optimum moisture content and then compacted to obtain a minimum relative compaction of 90 percent of the laboratory standard. Flooding/jetting is not recommended for the site soil materials. As an alternative. Imported sandy material with an S.E. of 30 or greater, may be flooded/jetted in shallow (12±inch or less) under-slab interior trenches, only. Mr. Leor Lakritz W.O. 2968-A-SC 2917 and 2925 State Street, Carlsbad January 9, 2001 File:e:\wp7\2900\2968a.pge Page 17 GeoSoils, Inc. 2. Sand backfill, unless trench excavafion material, should not be allowed in exterior trenches adjacent to and within an area extending below a 1:1 plane projected from the outside bottom edge of the foofing. 3. All trench excavafions should minimally conform to CAL-OSHA and local safety codes. 4. Soils generated from ufility trench excavafions to be used onsite should be compacted to 90 percent minimum relative compacfion. This material must not alter positive drainage patterns that direct drainage away from the structural area and towards the street. PLAN REVIEW Final site development and foundafion plans should be submitted to this office for review and comment, as the plans become available, for the purpose of minimizing any misunderstandings between the plans and recommendafions presented herein. In addifion, foundafion excavafions and any addifional earthwork construction performed on the site should be observed and tested by this office. If condifions are found to differ substantially from those stated, appropriate recommendations would be offered at that time. LIMITATIONS The materials encountered on the project site and utilized in our study are believed representative ofthe area; however, soil and bedrock materials vary in character between excavations and natural outcrops or conditions exposed during mass grading, site conditions may vary due to seasonal changes or other factors. GSI assumes no responsibility or liability for work, testing or recommendations performed or provided by others. The scope of work was performed within the limits of a budget. Inasmuch as our study is based upon the site materials observed, selective laboratory testing and engineering analysis, the conclusion and recommendations are professional opinions. These opinions have been derived in accordance with current standards of practice, and no warranty is expressed or implied. Standards of practice are subject to change with time. Mr. Leor Lakritz W.O. 2968-A-SC 2917 and 2925 State Street, Carlsbad January 9, 2001 File:e:\wp7\2900\2968a.pge Page 18 GeoSoils, Inc. APPENDIX A REFERENCES APPENDIX A REFERENCES Benton Engineering, Inc.,1970, Final Compaction Report, La Costa South Unit 7, August 10,1970, Project # 69-12-8D. Blake, Thomas F., 1997, EQFAULT computer program for the deterministic prediction of horizontal accelerations from digitized California faults. Campbell, K.W. and Bozorgnia, Y., 1994, Near-source attenuation of peak horizontal acceleration from woridwide accelrograms recorded from 1957 to 1993; Proceedings, Fifth U.S. National Conference on Earthquake Engineering, volume III, Earthquake Engineering Research Institute, pp 292-293. Hart, E.W. and Bryant, W.A. 1997, Fault-rupture Hazard Zones in California, Alquist-Priolo Earthquake Fault Zoning act with Index to Earthquake Fault Maps; California Division of Mines and Geology Special Publicafion 42. International Conference of Building Officials, 1997, Uniform building code: Whittier, California, vol. 1, 2, and 3. Jennings, C.W.,. 1994, Fault activity map of California and adjacent areas: California Division of Mines and Geology, Map Sheet No. 6, scale 1:750,000. Joyner, W.B., and Boore, D.M., 1982, Esfimafion of response-spectral values as fijncfions of magnitude, distance and site condifions, in eds., Johnson, J.A., Campbell, K.W., and Blake, T.F., AEG short course, seismic hazard analysis, dated June 18,1994. Petersen, Mark D., Bryant, W.A., and Cramer, C.H., 1996, Interim table of fault parameters used by the California Division of Mines and Geology to compile the probabilisfic seismic hazard maps of California. Sadigh, K., Egan, J., and Youngs, R., 1987, Predicfive ground mofion equafions reported in Joyner, W.B., and Boore, D.M., 1988, "Measurement, characterizafion, and predicfion of strong ground mofion", in Earthquake Engineering and Soil Dynamics II, Recent Advances in Ground Motion Evaluation, Von Thun, J.L., ed.: American Society of Civil Engineers Geotechnical Special Publication No. 20, pp. 43-102. Tan, S.S., and Kennedy, Michael P., 1996, Geologic maps ofthe northwestern part of San Diego County, California: California Division of Mines and Geology, Open File Report 96-02. GeoSoils, Inc. APPENDIX B BORING LOGS BORING LOG GeoSoils, Inc. PROJECT: LEOR LAKRITZ State Street, Carlsbad W.O. 2968-A-SC BORING B-1 Sample I T3 Ul 0) - n X) L C 3 3 +- 0 CO Sl U E CO 3 3 M SAMPLE METHOD: Hand Auger SHEET1 11-13-00 Standard Penetration Test Undisturbed, Ring Sample Water Seepage into hole Description of Material SM COLLUVIUM: @ 1', SILTY SAND, brown, dry, loose; porous. SM TERRACE DEPOSITS: (5) 2 1/2', SILTY SAND, brown, slightly moist, medium dense. 10- 15- 20- 25 Total Depth = 4' No groundwater encountered Backfilled 11-13-00 State Street, Carlsbad GeoSoils, Inc, PLATE B-1 BORING LOG GeoSoils, Inc. P/?0JFC7. LE0R LAKRITZ State Street, Carlsbad W.O. 2968-A-SC BORING B-2 Sample I T3 Ul 0) - .D XJ L C 3 3 +• 0 C/) il U E (/) D) D M DATE EXCAVATED SAMPLE METHOD: Hand Auger SHEET 1 0£ 1 11-13-00 Standard Penetration Test Undisturbed, Ring Sample Water Seepage into hole Description of Material SM COLLUVIUM: @ 0-2', SILTY SAND, dark brown, moist, loose; porous. 10 15- 20- 25 SM TERRACE DEPOSITS: @ 2', SILTY SAND, brown, moist, medium dense. \@ 6', SAND, light yellowish brown, medium dense. Total Depth = 6' No groundwater encountered Backfilled 11-13-00 State Street, Carlsbad GeoSoils, Inc. PLATE B-2 BORING LOG GeoSoils, Inc. P/?0J£C7. LE0R LAKRITZ State Street, Carlsbad W.O. 2968-A-SC BORING B-3 Sample I -D Ul 01 - XI Xl L C 3 =) -t- o V) n u E (A 3 DATE EXCAVATED SAMPLE METHOD: Hand Auger SHEET 1 OF 1 11-13-00 Standard Penetration Test Undisturbed, Ring Sample f<\j Water Seepage into hole Description of Material SM COLLUVIUM: @ 1', SILTY SAND, brown, dry, loose; porous. SM TERRACE DEPOSIT: @ 2 1/2', SILTY SAND, brown, slightly moist, medium dense. 5- 10- 15- 20 25 Total Depth = 4' No groundweater encountered Backfilled 11-13-00 State Street, Carlsbad GeoSoils, Inc. PLATE B-3 APPENDIX C LABORATORY DATA 100 90 80 U.S. SIEVE OPENING IN INCHES I U.S. SIEVE NUMBERS 6 ^3 ^ 1.5 ^ 3i4 ^'^m 3 4 8 8^° 14^6 20 ^0 4O ^0 go uo^^^ HYDROMETER 70 60 > CO mso UJ40 O a: III 30 20 10 100 10 1 0.1 GRAIN SIZE IN MILLIMETERS 0.01 0.001 COBBLES GRAVEL SAND SILT OR CLAY COBBLES coarse fine coarse medium fine SILT OR CLAY Sample Depth Ciassification LL PL PI Cc Cu B-1 15.0 Sample Depth D100 D60 D30 D10 %Gravel %Sand '/oSilt %Clay • B-1 15.0 19 0.288 0.171 0.3 85.5 14.3 GeoSoils, Inc. .5741 Palmer Way Carisbad, CA 92008 Telephone: (760)438-3155 Fax: (760)931-0915 GRAIN SIZE DISTRIBUTION Project: LAKRITZ Number: 2968-A-sc Date: November 2000 Figure: C-1 APPENDIX D GENERAL EARTHWORK AND GRADING GUIDELINES GENERAL EARTHWORK AND GRADING GUIDELINES General These guidelines present general procedures and requirements for earthwork and grading as shown on the approved grading plans, including preparation of areas to filled, placement of fill, installation of subdrains and excavations. The recommendations contained in the geotechnical report are part ofthe earthwork and grading guidelines and would supersede the provisions contained hereafter in the case of confiict. Evaluations performed by the consultant during the course of grading may result in new recommendations which could supersede these guidelines or the recommendations contained in the geotechnical report. The contractor is responsible for the satisfactory completion of all earthwork in accordance with provisions of the project plans and specificafions. The project soil engineer and engineering geologist (geotechnical consultant) or their representatives should provide observafion and tesfing services, and geotechnical consultafion during the durafion of the project. EARTHWORK OBSERVATIONS AND TESTING Geotechnical Consultant Prior to the commencement of grading, a qualified geotechnical consultant (soil engineer and engineering geologist) should be employed for the purpose of observing earthwork procedures and tesfing the fills for conformance with the recommendations of the geotechnical report, the approved grading plans, and applicable grading codes and ordinances. The geotechnical consultant should provide tesfing and observafion so that determination may be made that the work is being accomplished as specified. \t is the responsibility of the contractor to assist the consultants and keep them apprised of anticipated work schedules and changes, so that they may schedule their personnel accordingly. All clean-outs, prepared ground to receive fill, key excavafions, and subdrains should be observed and documented by the project engineering geologist and/or soil engineer prior to placing and fill. It is the contractors's responsibility to notify the engineering geologist and soil engineer when such areas are ready for observation. Laboratory and Fleld Tests Maximum dry density tests to determine the degree of compaction should be performed in accordance with American Standard Testing Materials test method ASTM designation D-1557-78. Random field compaction tests should be performed in accordance with test method ASTM designation D-1556-82, D-2937 or D-2922 and D-3017, at inten/als of approximately 2 feet of flll height or every 100 cubic yards of flll placed. These criteria GeoSoils, Inc. would vary depending on the soil conditions and the size of the project. The locafion and frequency of testing would be at the discrefion of the geotechnical consultant. Contractor's Responsibility All clearing, site preparafion, and earthwork performed on the project should be conducted by the contractor, with observation by geotechnical consultants and staged approval by the governing agencies, as applicable. \X is the contractor's responsibility to prepare the ground surface to receive the fill, to the safisfacfion of the soil engineer, and to place, spread, moisture condifion, mix and compact the fill in accordance with the recommendafions of the soil engineer. The contractor should also remove all major non- earth material considered unsafisfactory by the soil engineer. It is the sole responsibility of the contractor to provide adequate equipment and methods to accomplish the earthwork in accordance with applicable grading guidelines, codes or agency ordinances, and approved grading plans. Sufficient watering apparatus and compaction equipment should be provided by the contractor with due consideration for the fill material, rate of placement, and climatic conditions. If, In the opinion of the geotechnical consultant, unsatisfactory conditions such as questionable weather, excessive oversized rock, or deleterious material, insufficient support equipment, etc., are resulting in a quality of work that is not acceptable, the consultant will inform the contractor, and the contractor is expected to rectify the conditions, and if necessary, stop work until conditions are satisfactory. During construction, the contractor shall properly grade all surfaces to maintain good drainage and prevent ponding of water. The contractor shall take remedial measures to control surface water and to prevent erosion of graded areas until such time as permanent drainage and erosion control measures have been installed. SITE PREPARATION All major vegetation, including brush, trees, thick grasses, organic debris, and other deleterious material should be removed and disposed of off-site. These removals must be concluded prior to placing fill. Exisfing fill, soil, alluvium, colluvium, or rock materials determined by the soil engineer or engineering geologist as being unsuitable in-place should be removed prior to fill placement. Depending upon the soil condifions, these materials may be reused as compacted fills. Any materials incorporated as part of the compacted fills should be approved by the soil engineer. Any underground structures such as cesspools, cisterns, mining shafts, tunnels, sepfic tanks, wells, pipelines, or other structures not located prior to grading are to be removed or treated in a manner recommended by the soil engineer. Soft, dry, spongy, highly fractured, or othen/vise unsuitable ground extending to such a depth that surface processing cannot adequately improve the condition should be overexcavated down to Mr. Leor Lakritz Appendix D Flle:e:\wp7\2900\2968a.pge Page 2 GeoSoils, Inc. firm ground and approved by the soil engineer before compaction and filling operations continue. Overexcavated and processed soils which have been properly mixed and moisture conditioned should be re-compacted to the minimum relafive compacfion as specified in these guidelines. Existing ground which is determined to be safisfactory for support of the fills should be scarified to a minimum depth of 6 inches or as directed by the soil engineer. After the scarified ground is brought to opfimum moisture content or greater and mixed, the materials should be compacted as specified herein. If the scarified zone is grater that 6 inches in depth, it may be necessary to remove the excess and place the material in lifts restricted to about 6 inches in compacted thickness. Existing ground which is not satisfactory to support compacted fill should be overexcavated as required in the geotechnical report or by the on-site soils engineer and/or engineering geologist. Scarificafion, disc harrowing, or other acceptable form of mixing should confinue until the soils are broken down and free of large lumps or clods, until the working surface is reasonably uniform and free from ruts, hollow, hummocks, or other uneven features which would inhibit compaction as described previously. Where fills are to be placed on ground with slopes steeper than 5:1 (horizontal to vertical), the ground should be stepped or benched. The lowest bench, which will act as a key, should be a minimum of 15 feet wide and should be at least 2 feet deep into firm material, and approved by the soil engineer and/or engineering geologist. In fill over cut slope condifions, the recommended minimum width ofthe lowest bench or key is also 15 feet with the key founded on firm material, as designated by the Geotechnical Consultant. As a general rule, unless specifically recommended otherwise by the Soil Engineer, the minimum width of fill keys should be approximately equal to Vz the height of the slope. Standard benching is generally 4 feet (minimum) vertically, exposing firm, acceptable material. Benching may be used to remove unsuitable materials, although it is understood that the vertical height ofthe bench may exceed 4 feet. Pre-stripping may be considered for unsuitable materials in excess of 4 feet In thickness. All areas to receive fill. Including processed areas, removal areas, and the toe of fill benches should be observed and approved by the soil engineer and/or engineering geologist prior to placement of fill. Fills may then be properly placed and compacted unfil design grades (elevafions) are aftained. COMPACTED FILLS Any earth materials imported or excavated on the property may be ufilized in the fill provided that each material has been determined to be suitable by the soil engineer. These materials should be free of roots, tree branches, other organic matter or other deleterious materials. All unsuitable materials should be removed from the fill as directed Mr. Leor Lakritz Appendix D File:e:\wp7\2900\2968a.pge Page 3 GeoSoils, Inc. by the soil engineer. Soils of poor gradafion, undesirable expansion potenfial, or substandard strength characteristics may be designated by the consultant as unsuitable and may require blending with other soils to sen/e as a satisfactory fill material. Fill materials derived from benching operations should be dispersed throughout the fill area and blended with other bedrock derived material. Benching operafions should not result in the benched material being placed only within a single equipment width away from the fill/bedrock contact. Oversized materials defined as rock or other irreducible materials with a maximum dimension greaterthan 12 inches should not be buried or placed in fills unless the locafion of materials and disposal methods are specifically approved by the soil engineer. Oversized material should be taken off-site or placed in accordance with recommendations ofthe soil engineer in areas designated as suitable for rock disposal. Oversized material should not be placed within 10 feet vertically of finish grade (elevafion) or within 20 feet horizontally of slope faces. To facilitate fljture trenching, rock should not be placed within the range of foundafion excavafions, future utilities, or underground construction unless specifically approved by the soil engineer and/or the developers representative. If import material is required for grading, representative samples of the materials to be utilized as compacted fill should be analyzed in the laboratory by the soil engineer to determine Its physical properties. If any material other than that previously tested is encountered during grading, an appropriate analysis of this material should be conducted by the soil engineer as soon as possible. Approved fill material should be placed in areas prepared to receive fill in near horizontal layers that when compacted should not exceed 6 inches in thickness. The soil engineer may approve thick lifts if tesfing indicates the grading procedures are such that adequate compacfion is being achieved with lifts of greater thickness. Each layer should be spread evenly and blended to attain uniformity of material and moisture suitable for compacfion. Fill layers at a moisture content less than opfimum should be watered and mixed, and wet fill layers should be aerated by scarification or should be blended with drier material. Moisture condition, blending, and mixing of the fill layer should continue unfil the fill materials have a uniform moisture content at or above optimum moisture. After each layer has been evenly spread, moisture condifioned and mixed, it should be uniformly compacted to a minimum of 90 percent of maximum density as determined by ASTM test designafion, D-1557-78, or as othenA/ise recommended by the soil engineer. Compacfion equipment should be adequately sized and should be specifically designed for soil compacfion or of proven reliability to efficiently achieve the specified degree of compacfion. Mr. Leor Lakritz Appendix D nie:e:\wp7\2900\2968a.pge Page 4 GeoSoils, Inc. Where tests indicate that the density of any layer of fill, or portion thereof, is below the required relative compacfion, or improper moisture is in evidence, the particular layer or portion shall be re-worked unfil the required density and/or moisture content has been attained. No addifional fill shall be placed in an area unfil the last placed lift of fill has been tested and found to meet the density and moisture requirements, and is approved by the soil engineer. Compaction of slopes should be accomplished by over-building a minimum of 3 feet horizontally, and subsequently trimming back to the design slope configurafion. Tesfing shall be performed as the fiil is elevated to evaluate compacfion as the fill core is being developed. Special efforts may be necessary to attain the specified compaction in the fill slope zone. Final slope shaping should be performed by trimming and removing loose materials with appropriate equipment. Afinal determinafion of fill slope compacfion should be based on observafion and/or testing ofthe finished slope face. Where compacted fill slopes are designed steeper than 2:1 (horizontal to vertical), specific material types, a higher minimum relative compacfion, and special grading procedures, may be recommended. If an alternative to over-building and cutting back the compacted fill slopes is selected, then special effort should be made to achieve the required compacfion in the outer 10 feet of each lift of fill by undertaking the following: 1. An extra piece of equipment consisting of a heavy short shanked sheepsfoot should be used to roll (horizontal) parallel to the slopes confinuously as fill is placed. The sheepsfoot roller should also be used to roll perpendicular to the slopes, and extend out over the slope to provide adequate compacfion to the face of the slope. 2. Loose fill should not be spilled out over the face of the slope as each lift is compacted. Any loose fill spilled over a previously completed slope face should be trimmed off or be subject to re-rolling. 3. Field compaction tests will be made in the outer (horizontal) 2 to 8 feet of the slope at appropriate vertical intervals, subsequent to compacfion operafions. 4. After complefion of the slope, the slope face should be shaped with a small tractor and then re-rolled with a sheepsfoot to achieve compaction to near the slope face. Subsequent to tesfing to verify compacfion, the slopes should be grid-rolled to achieve compacfion to the slope face. Final tesfing should be used to confirm compaction after grid rolling. 5. Where tesfing indicates less than adequate compacfion, the contractor will be responsible to rip, water, mix and re-compact the slope material as necessary to achieve compaction. Addifional testing should be performed to verify compaction. Mr. Leor Lakritz Appendix D File:e:\wp7\2900\2968a.pge Page 5 GeoSoils, Inc. 6. Erosion control and drainage devices should be designed by the project civil engineer in compliance with ordinances ofthe controlling governmental agencies, and/or in accordance with the recommendation of the soil engineer or engineering geologist. SUBDRAIN INSTALLATION Subdrains should be installed in approved ground in accordance with the approximate alignment and details indicated by the geotechnical consultant. Subdrain locafions or materials should not be changed or modified without approval of the geotechnical consultant. The soil engineer and/or engineering geologist may recommend and direct changes in subdrain line, grade and drain material in the field, pending exposed condifions. The locafion of constructed subdrains should be recorded by the project civil engineer. EXCAVATIONS Excavations and cut slopes should be examined during grading by the engineering geologist. If directed by the engineering geologist, further excavations or overexcavation and re-filling of cut areas should be performed and/or remedial grading of cut slopes should be performed. When fill over cut slopes are to be graded, unless otherwise approved, the cut portion of the slope should be observed by the engineering geologist prior to placement of materials for construcfion of the fill portion of the slope. The engineering geologist should observe all cut slopes and should be notified by the contractor when cut slopes are started. If, during the course of grading, unforeseen adverse or potenfial adverse geologic condifions are encountered, the engineering geologist and soil engineer should invesfigate, evaluate and make recommendafions to treat these problems. The need for cut slope buttressing or stabilizing should be based on in-grading evaluafion by the engineering geologist, whether anficipated or not. Unless otherwise specified In soil and geological reports, no cut slopes should be excavated higher or steeper than that allowed by the ordinances of controlling governmental agencies. Addifionally, short-term stability of temporary cut slopes is the contractors responsibility. Erosion control and drainage devices should be designed by the project civil engineer and should be constructed in compliance with the ordinances ofthe controlling governmental agencies, and/or in accordance with the recommendafions of the soil engineer or engineering geologist. Mr. Leor Lakritz Appendix D Flle:e:\wp7\2900\2968a.pge Page 6 GeoSoils, Inc. COMPLETION Observafion, tesfing and consultafion by the geotechnical consultant should be conducted during the grading operations in order to state an opinion that all cut and filled areas are graded in accordance with the approved project specificafions. After complefion of grading and after the soil engineer and engineering geologist have finished their observafions of the work, final reports should be submitted subject to review by the controlling governmental agencies. No further excavafion or filling should be undertaken without prior notificafion of the soil engineer and/or engineering geologist. All finished cut and fill slopes should be protected from erosion and/or be planted in accordance with the project specifications and/or as recommended by a landscape architect. Such protection and/or planning should be undertaken as soon as pracfical after completion of grading. JOB SAFETY General At GeoSoils, Inc. (GSI) getting the job done safely is of primary concern. The following is the company's safety considerafions for use by all employees on mulfi-employer construcfion sites. On ground personnel are at highest risk of injury and possible fatality on grading and construcfion projects. GSI recognizes that construction activities will vary on each site and that site safety is the prime responsibility of the contractor; however, everyone must be safety conscious and responsible at all fimes. To achieve our goal of avoiding accidents, cooperafion between the client, the contractor and GSI personnel must be maintained. In an effort to minimize risks associated with geotechnical tesfing and observafion, the following precaufions are to be implemented for the safety of field personnel on grading and construction projects: Safety Meetings: GSI field personnel are directed to attend contractors regulariy scheduled and documented safety meefings. Safety Vests: Safety vests are provided for and are to be worn by GSI personnel at all fimes when they are working in the field. Safety Flags: Two safety flags are provided to GSI fleld technicians; one is to be affixed to the vehicle when on site, the other Is to be placed atop the spoil pile on all test pits. Mr. Leor Lakritz Appendix D File:e:\wp7\2900\2968a.pge Page 7 GeoSoils, Inc. Flashing Lights: All vehicles stafionary in the grading area shall use rotafing or flashing amber beacon, or strobe lights, on the vehicle during all fleld tesfing. While operafing a vehicle In the grading area, the emergency flasher on the vehicle shall be acfivated. In the event that the contractor's representative obsen/es any of our personnel not following the above, we request that it be brought to the attenfion of our office. Test Pits Location, Orientation and Clearance The technician is responsible for selecting test pit locations. A primary concern should be the technicians's safety. Efforts will be made to coordinate locations with the grading contractors authorized representative, and to select locations following or behind the established traffic pattern, preferably outside of current traffic. The contractors authorized representative (dump man, operator, supervisor, grade checker, etc.) should direct excavafion ofthe pit and safety during the test period. Of paramount concern should be the soil technicians safety and obtaining enough tests to represent the fill. Test pits should be excavated so that the spoil pile is placed away form oncoming traffic, whenever possible. The technician's vehicle is to be placed next to the test pit, opposite the spoil pile. This necessitates the fill be maintained in a driveable condifion. Alternatively, the contractor may wish to park a piece of equipment in front of the test holes, particularly in small fill areas or those with limited access. A zone of non-encroachment should be established for all test pits. No grading equipment should enter this zone during the tesfing procedure. The zone should extend approximately 50 feet outward from the center of the test pit. This zone is established for safety and to avoid excessive ground vibrafion which typically decreased test results. When taking slope tests the technician should park the vehicle directly above or below the test locafion. If this is not possible, a prominent fiag should be placed at the top of the slope. The contractor's representafive should effecfively keep all equipment at a safe operafion distance (e.g. 50 feet) away from the slope during this tesfing. The technician is directed to withdraw from the active portion of the fill as soon as possible following tesfing. The technician's vehicle should be parked at the perimeter of the fill in a highly visible location, well away from the equipment traffic pattern. The contractor should inform our personnel of all changes to haul roads, cut and fill areas or other factors that may affect site access and site safety. In the event that the technicians safety is jeopardized or compromised as a result of the contractors failure to comply with any ofthe above, the technician Is required, by company policy, to immediately withdraw and notify his/her supen/isor. The grading contractors representafive will eventually be contacted in an effort to effect a solufion. However, in the Mr. Leor Lakritz Appendix D Flle:e:\wp7\2900\2968a.pge Page 8 GeoSoils, Inc. Interim, no fijrther tesfing will be performed unfil the situafion is rectified. Any fill place can be considered unacceptable and subject to reprocessing, recompacfion or removal. In the event that the soil technician does not comply with the above or other established safety guidelines, we request that the contractor brings this to his/her attenfion and notify this office. Effecfive communication and coordination between the contractors representative and the soils technician is strongly encouraged In order to implement the above safety plan. Trench and Vertical Excavation \X is the contractor's responsibility to provide safe access into trenches where compacfion tesfing is needed. Our personnel are directed not to enter any excavation or vertical cut which 1) is 5 feet or deeper unless shored or laid back, 2) displays any evidence of instability, has any loose rock or other debris which could fall into the trench, or 3) displays any other evidence of any unsafe condifions regardless of depth. All trench excavations or vertical cuts in excess of 5 feet deep, which any person enters, should be shored or laid back. Trench access should be provided in accordance with CAL-OSHA and/or state and local standards. Our personnel are directed not to enter any trench by being lowered or "riding down" on the equipment. If the contractor fails to provide safe access to trenches for compacfion tesfing, our company policy requires that the soil technician withdraw and notify his/her supervisor. The contractors representative will eventually be contacted in an effort to effect a solution. All backfill not tested due to safety concerns or other reasons could be subject to reprocessing and/or removal. If GSI personnel become aware of anyone working beneath an unsafe trench wall or vertical excavafion, we have a legal obligation to put the contractor and owner/developer on nofice to immediately correct the situation. If corrective steps are not taken, GSI then has an obligation to notify CAL-OSHA and/or the proper authorities. Mr. Leor Lakritz Appendix D Rle:e:\wp7\2900\2968a.pge Page 9 GeoSoils, Inc. CANYON SUBDRAIN DETAIL TYPE A PROPOSED COMPACTED FILL NATURAL GROUND COLLUVIUM AND ALLUVIUM (REMOVE) —> y\ TYPICAL BENCHING ^^^^^ ^ SEE ALTERNATIVES TYPE B \ \ \ PROPOSED COMPACTED FILL NATURAL GROUND COLLUVIUM AND ALLUVIUM (REMOVE) ^ BEDROCK TYPICAL BENCHING SEE ALTERNATIVES NOTE: ALTERNATIVES. LOCATICN AND EXTENT OF SUBDRAINS SHOULD BE DETERMINED BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST DURING GRADING. PLATE EG-1 CANYON SUBDRAIN ALTERNATE DETAILS ALTERNATE 1: PERFORATED PIPE AND FILTER MATERIAL A-1 MINIMUM 12" MINIMUM FILTER MATERIAL MINIMUM VOLUME OF 9 FT.> '^^fT^. /LINEAR FT. 6' iJ ABS OR PVC PIPE OR APPROVED ^••.V. '.V. SUBSTITUTE WITH MINIMUM 8 iUrfi PERFS. ^^- -^ LINEAR FT. IN BOTTOM HALF OF PIPE. ASTM D2751. SDR 35 OR ASTM D1527, SCHD^ ^0 ASTM D303^. SDR 35 OR ASTM D1785. SCHD. AO FOR CONTINUOUS RUN IN EXCESS OF56o FT. USE 8"^f PIPE 6' MINIMUM B-1 FILTER MATERIAL SIEVE SIZE PERCENT PA??|N(? 1 INCH :100 3/4 INCH 90-100 3/8 INCH 40-100 NO. 4 25-40. NO.S 18-33 NO. 30 .5-15 NO, 50 .0-7 NO. 200 0-3 ALTERNATE 2: PERFORATED PIPE, GRAVEL AND.FILTER FABRIC 6'MINIMUM OVERLAP 6-MINIMUM OVERLAP 6'MINIMUM COVER = 4-MINIMUM BEDDING A-2 B-2 4- MINIMUM BEDDING GRAVEL MATERIAL 9 Fr/LINEAR FT. PERFORATED PIPE: SEE ALTERNATE 1 GRAVEL CLEAN 3/4 INCH ROCK OR APPROVED SUBSTITUTE FILTER FABRIC: MIRAFI 140 OR APPROVED SUBSTITUTE PLATE EG-2 DETAIL FOR FILL SLOPE TOEING OUT ON FLAT ALLUVIATED CANYON TOE OF SLOPE AS SHOWN ON GRADING PLAN ORIGINAL GROUND SURFACE TO BE RESTORED WITH COMPACTED FILL BACKCUT\J/ARIES. FOR DEEP REMOVALS./^ COMPACTED RLL ORIGINAL GROUND SURFACE BACKCUT SHOULD BE MAOE NO STEEPER THAl\j:l OR AS NECESSARY -^N FOR SAFETY v,^^ONSIDERATIONS, ^ r / ANTICIPATED ALLUVIAL REMOVAL DEPTH PER SOIL ENQINEER. PROVIDE A 1:1 MINIMUM PROJECTION FROM TOE OF SLOPE AS SHOWN ON GRADING PLAN TO THE RECOMMENDED REMOVAL DEPTH. SLOPE HEIGHT. SITE CONDITIONS ANO/OR LOCAL CONDITIONS COULD DICTATE FLATTER PROJECTIONS. REMOVAL ADJACENT TO EXISTING FILL ADJOINING CANYON FILL COMPACTED RLL LIMITS LINE Qcf U TEMPORARY COMPACTED RLL NLY ' Qal (TO BE REMOVED) 'vox (EXISTING COMPACTED RLL) ^^'N BE REMOVED BEFORE PLACING ADDITIONAL COMPACTED FILL Qaf ARTIFICIAL FILL Qal ALLUVIUM PLATE EG-3 TYPICAL STABILIZATION / BUTTRESS FILL DETAIL 15' TYPICAL 1-2' CLEA r" > m m o I ^TOE OUTLETS TO BE SPACED AT 100* MAXIMUM INTERVALS. AND SHALL EXTEND 12' BEYOND THE FACE OF SLOPE AT TIME OF. ROUGH GRADING COMPLETION. DESIGN FINISH SLOPE ^J%5'MINIMUM I j BLANKET FILL IF RECOMMENDED BY THE SOIL ENGINEER 10'MINIMUM W = 15'MINIMUM OR H/2 2 5 • M AX IM U KOrflJj;;^ TYPICAL BENCHING BUTTRESS OR SIDEHILL FILL ^2% GRADIENT DIAMETER NON-PERFORATED OUTLET PIPE AND BACKDRAIN (SEE ALTERNATIVES) BEDROCK 3'MINIMUM KEY DEPTH TYPICAL STABILIZATION / BUTTRESS SUBDRAIN DETAIL 4- MINIMUM PIPE 2" MINIMUM L' MINIMUM PIPE r" > m m o I Ol 2" MINIMUM FILTER MATERIAL MINIMUM OF FIVE FtVLINEAR Ft OF PIPF OR FOUR FtVLINEAR Fl OF PIPE WHEN PLACED IN SQUARE CUT TRENCH. ALTERNATIVE IN LIEU OF FILTER MATERIAL: GRAVEL MAY BE ENCASED IN APPROVED FILTER FABRIC. RLTER FABRIC SHALL BE MIRAFI 140 OR EQUIVALENT. FILTER FABRIC SHIALL BE LAPPED A MINIMUM OF 12" ON ALL JOINTS. MINIMUM 4- DIAMETER PIPE: ABS-ASTM D-2751. SDR 35 OR ASTM D-1527 SCHEDULE 40 PVC-ASTM D-3034. SpR 35 OR ASTM D-1785 SCHEDULE 40 WITH A CRUSHING STRENGTH OF 1.000 POUNDS MINIMUM, AND A MINIMUM OF 8 UNIFORMLY SPACED PERFORATIONS PER FOOT OF PIPE INSTALLED WITH PERFORATIONS OF BOTTOM OF PIPE. PROVIDE CAP AT UPSTREAM END OF PIPE. SLOPE AT 2% TO OUTLET PIPE. OUTLET PIPE TO BE CONNECTED TO SUBDRAIN PIPE WITH TEE OR ELBOW. NOTE: 1. TRENCH FOR OUTLET PIPES TO BE BACKFILLED WITH ON-SITE SOIL 2. BACKDRAINS AND LATERAL DRAINS SHALL BE LOCATED AT ELEVATION OF EVERY BENCH DRAIN. RRST DRAIN LOCATED AT ELEVATION JUST ABOVE LOWER LOT GRADE. ADDITIONAL DRAINS MAY BE REQUIRED AT THE DISCRETION OF THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST. FILTER MATERIAL SHALL BE OF THE FOLLOWING SPECIFICATION OR AN APPROVED EQUIVALENT: SIEVE SIZE PERCENT PASSING 1 INCH 100 3/4 INCH 90-100 3/8 INCH 40-100 NO. 4 25-40 NO. 8 18-33 NO. 30 5-15 NO. 50 0-7 NO. 200 0-3 GRAVEL SHALL BE OF THE FOLLOWING SPECIFICATION OR AN APPROVED EQUIVALENT: SIEVE SIZE PERCENT PASSING 1 1/2 INCH NO. 4 NO. 200 100 50 8 SAND EQUIVALENT: MINIMUM OF 50 FILL OVER NATURAL DETAIL SIDEHILL FILL PROPOSED GRADE TOE OF SLOPE AS SHOWN ON GRADING PLAN PROVIDE A 1:1 MINIMUM PROJECTION FROM DESIGN TOE OF SLOPE TO TOE OF KEY AS SHOWN ON AS BUILT 1— > m m o I cn NATURAL SLOPE TO BE RESTORED WITH COMPACTED FILL BACKCUT VARIES I^WOTT-MINIMUM 15'MINIMUM KEY WIDTH 2'X 3'MINIMUM KEY DEPTH 2'MINIMUM IN BEDROCK OR APPROVED MATERIAL. f^^\y/^V/AW^ B^NCH WIDTH MAY VARY ^Jr. MINIMUM NOTE: 1. WHERE THE NATURAL SLOPE APPROACHES OR EXCEEDS THE DESIGN SLOPE RATIO. SPECIAL RECOMMENDATIONS WOULD BE PROVIDED BY THE SOILS ENGINEER. 2. THE NEED FOR AND DISPOSITION OF DRAINS WOULD BE DETERMINED BY THE SOILS ENGINEER BASED UPON EXPOSED CONDITIONS. RLL OVER CUT DETAIL CUT/RLL CONTACT L AS SHOWN ON GRADING PLAN 2. AS SHOWN ON AS BUILT MAINTAIN MINIMUM 15'FILL SECTION FROM BACKCUT TO FACE OF FINISH SLOPE ^'MINIMUM ^^/^ BEDROCK OR APPROVED MATERIAL LOWEST BENCH WIDTH 15'MINIMUM OR H/2 MINIMUM BENCH WIDTH MAY VARY > m m o I NOTE: THE CUT PORTION OF THE SLOPE SHOULD BE EXCAVATED AND EVALUATED BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST PRIOR TO CONSTRUCTING THE FILL PORTION. STABILIZATION FILL FOR UNSTABLE MATERIAL EXPOSED IN PORTION OF CUT SLOPE RNISHED GRADE > m m o I OO <fi. 1^ UNWEATHERED BEDROCK OR APPROVED MATERIAL COMPACTED STABILIZATION RLL V MINIMUM TILTED BACK IF RECOMMENDED BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST. THE REMAINING CUT PORTION OF THE SLOPE MAY REQUIRE REMOVAL AND REPLACEMENT WITH COMPACTED RLL NOTE: 1. SUBDRAINS ARE NOT REQUIRED UNLESS SPECIFIED BY SOILS ENOINEER AND/OR ENGINEERING GEOLOGIST, 2. -W- SHALL BE EQUIPMENT WIDTH (15'» FOR SLOPE HEIGHTS LESS THAN 25 FEET. FOR SLOPES GREATER THAN 25 FEET "W SHALL BE DETERMINED BY THE PROJECT SOILS ENOINEER AND /OR ENGINEERING GEOLOGIST. AT NO TIME SHALL "W" BE LESS THAN H/2. SKIN RLL OF NATURAL GROUND ORIGINAL SLOPE ROPOSED FINISH GRADE 15'MINIMUM TO BE MAINTAINED FROM PROPOSED FINISH SLOPE FACE TO BACKCUT PROPOSED FINISH SLOPE •Ei MINIMUM ^^^^^^ ^ '3'MINIMUM KEY DEPTH ^V^WV^ BEDROCK OR APPROVED MATERIAL H m m o I CD NOTE: 1. THE NEED AND DISPOSITION OF DRAINS WILL BE DETERMINED! BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST BASED ON RELD CONDITIONS. 2. PAD OVEREXCAVATION AND RECOMPACTION SHOULD BE PERFORMED IF DETERMINED TO BE NECESSARY BY THE SOILS ENGINEER AND/OR ENGINEERINO GEOLOGIST. DAYLIGHT CUT LOT DETAIL RECONSTRUCT COMPACTED RLL SLOPE AT 2:1 OR FLATTER IMAY INCREASE OR DECREASE PAD AREAL OVEREXCAVATE AND RECOMPACT REPLACEMENT RLL PROPOSED FINISH GRADE AVOID AND/OR CLEAN UP SPILLAGE OF MATERIALS ON THE NATURAL SLOPE Ta* MINIMUM BLANKET FILL BEDROCK OR APPROVED MATERIAL TYPICAL BENCHING % GRADIENT,x/^. "0 r- > m m o o NOTE: 1. SUBDRAIN AND KEY WIDTH REQUIREMENTS WILL BE DETERMINED BASED ON EXPOSED SUBSURFACE CONDITIONS AND THICKNESS OF OVERBURDEN. 2. PAD OVER EXCAVATION AND RECOMPACTION SHOULD BE PERFORMED IF DETERMINED NECESSARY BY THE SOILS ENGINEER AND/OR THE ENGINEERING GEOLOGIST. TRANSITION LOT DETAIL CUT LOT (MATERIAL TYPE TRANSITION) NATURAL GRADE COMPACTED FILL OVEREXCAVATE AHD RECOMPACT "y^^ 3- MINIMUM' ^ UNWEATHERED BEDROCK OR APPROVED MATERIAL TYPICAL BENCHING CUT-FILL LOT (DAYUGHT TRANSITION) TYPICAL BENCHING VV-^''.^^ |/A\V/\\V//\\V^\-^^^^ 3-MINIMUM' y, UNWEATHERED BEDROCK OR APPROVED MATERIAL NOTE: * DEEPER OVEREXCAVATION MAY BE RECOMMENDED BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST IN STEEP CUT-FILL TRANSITION AREAS. PLATE EG-11 SETTLEMENT PLATE AND RISER DETAIL 2'X 2'X 1/4" STEEL PLATE STANDARD 3/4" PIPE NIPPLE WELDED TO TOP OF PLATE. 3/4" X 5* GALVANIZED PIPE. STANDARD PIPE THREADS TOP AND BOTTOM. EXTENSIONS THREADED ON BOTH ENDS AND ADDED IN 5' INCREMENTS. 3 INCH SCHEDULE 40 PVC PIPE SLEEVE. ADD IN 5'INCREMENTS WITH GLUE JOINTS. FINAL GRADE MAINTAIN 5* CLEARANCE OF HEAVY EQUIPMENT. MECHANICALLY HAND COMPACT IN 2'VERTICAL -rAr LIFTS OR ALTERNATIVE SUITABLE TO AND I ACCEPTED BY THE SOILS ENGINEER. MECHANICALLY HAND COMPACT THE INITIAL 5* VERTICAL WITHIN A 5* RADIUS OF PLATE BASE. V... ..ryrvTr^^ :./ BOTT ' 1 f \» »...... ... » .ji BOTTOM OF CLEANOUT PROVIDE A MINIMUM 1'BEDDING OF COMPACTED SAND NOTE: 1. LOCATIONS OF SETTLEMENT PLATES SHOULD BE CLEARLY MARKED AND READILY VISIBLE (RED FLAGGED) TO EQUIPMENT OPERATORS. 2. CONTRACTOR SHOULD MAINTAIN CLEARANCE OF A 5* RADIUS OF PLATE BASE AND WITHIN 5'(VERTICAL) FOR HEAVY EQUIPMENT. RLL WITHIN CLEARANCE AREA SHOULD BE HAND COMPACTED TO PROJECT SPECIRCATIONS OR COMPACTED BY ALTERNATIVE APPROVED BY THE SOILS ENGINEER. 3. AFTER 5*(VERTICAL) OF FILL IS IN PLACE. CONTRACTOR SHOULD MAINTAIN A 5'RADIUS EQUIPMENT CLEARANCE FROM RISER. 4. PLACE AND MECHANICALLY HAND COMPACT INITIAL 2* OF RLL PRIOR TO ESTABLISHING THE INITIAL READING. 5. IN THE EVENT OF DAMAGE TO THE SETTLEMENT PLATE OR EXTENSION RESULTING FROM EQUIPMENT OPERATING WITHIN THE SPECIFIED CLEARANCE AREA. CONTRACTOR SHOULD IMMEDIATELY NOTIFY THE SOILS ENGINEER AND SHOULD BE RESPONSIBLE FOR RESTORING THE SETTLEMENT PLATES TO WORKING ORDER. 5. AN ALTERNATE DESIGN AND METHOD OF INSTALLATION MAY BE PROVIDED AT THE DISCRETION OF THE SOILS ENGINEER. PLATE EG-U TYPICAL SURFACE SETTLEMENT MONUMENT RNISH GRADE 3'-6* 3/8- DIAMETER X LENGTH CARRIAGE BOLT OR EQUIVALENT •-6" DIAMETER X 3 1/2* LENGTH HOLE CONCRETE BACKRLL PLATE EG-15 TEST PIT SAFETY DIAGRAM SIDE VIEW ( NOT TO SCALE ) TOP VIEW 100 FE£T 50 FEET FUkG SPOIL PILE iii u. a in 50 FEET APPROXIMATE CENTER GF TEST PIT VB«CLE III FLAG I NOT TO SCALE ) PLATE EG—16 OVERSIZE ROCK DISPOSAL VIEW NORMAL TO SLOPE FACE OO 20'MINIMUM oo J5'MINIMUM (AL^ MINIMUM (C) oo oo PROPOSED FINISH GRADE 10'MINIMUM (E) CO CO 15'MINIMUM (A) oo ^oo oo oo (G) ooiF) BEDROCK OR APPROVED MATERIAL VIEW PARALLEL TO SLOPE FACE PROPOSED RNISH GRADE FROM jlMINIMUM (C) BEDROCK OR APPROVED MATERIAL NOTE: (A) (B) (C) (D) (E) (R (G) ONE EQUIPMENT WIDTH OR A MINIMUM OF 15 FEET. HEIGHT AND WIDTH MAY VARY DEPENDING ON ROCK SIZE AND TYPE OF EQUIPMENT. LENGTH OF WINDROW SHALL BE NO GREATER THAN 100* MAXIMUM. IF APPROVED BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST. WINDROWS MAY BE PLACED DIRECTLY ON COMPETENT MATERIAL OR BEDROCK PROVIDED ADEQUATE SPACE IS AVAILABLE FOR COMPACTION. ORIENTATION OF WINDROWS MAY VARY BUT SHOULD BE AS RECOMMENDED BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST. STAGGERING OF WINDROWS IS NOT NECESSARY UNLESS RECOMMENDED. CLEAR AREA FOR UTILITY TRENCHES. FOUNDATIONS AND SWIMMING POOLS. ALL RLL OVER AND AROUND ROCK WINDROW SHALL BE COMPACTED TO 90% RELATIVE COMPACTION OR AS RECOMMENDED. AFTER FILL BETWEEN WINDROWS IS PLACED AND COMPACTED WITH THE LIFT OF FILL COVERING WINDROW. WINDROW SHOULD BE PROOF ROLLED WITH A D-9 DOZER OR EQUIVALENT. VIEWS ARE DIAGRAMMATIC ONLY. ROCK SHOULD NOT TOUCH AND VOIDS SHOULD BE COMPLETELY RLLED IN. PLATE RD""1 ROCK DISPOSAL PITS VIEWS ARE DIAGRAMMATIC ONLY. ROCK SHOULD NOT TOUCH AND VOIDS SHOULD BE COMPLETELY RLLED IN. RLL LIFTS COMPACTED OVER ROCK AFTER EMBEDMENT r I I I GRANULAR MATERIAL j COMPACTED RLL SIZE OF EXCAVATION TO BE COMMENSURATE WITH ROCK SIZE ROCK DISPOSAL LAYERS GRANULAR SOIL TO RLL VOIDS. DENSIRED BY FLOODING LAYER ONE ROCK HIGH \1 ^OMPACTED RLL I PROPOSED RNISH GRADE 10'MINIMUM OR BELOW LOWEST UTIUT QCXXDOCC OVERSIZE LAYER ^ , COMPACTED RLL fs'MINIMUM PROFILE ALONG LAYER LOPE FACE J^CLEAR ZONE 20'MINIMUM LAYER ONE ROCK HIGH PLATE RD-2