Loading...
HomeMy WebLinkAboutCC AG PKT 2012-06-25 #M (attachment 12) ATTACHMENT 12 DRAFT RESOLUTION CERTIFYING THE FINAL EIR, MAKING FINDINGS AND ADOPTING THE MITIGATION MONITORING PROGRAM RESOLUTION NUMBER 6273 A RESOLUTION OF THE SEAL BEACH CITY COUNCIL CERTIFYING THE FINAL ENVIRONMENTAL IMPACT REPORT FOR THE DEPARTMENT OF WATER AND POWER SPECIFIC PLAN AMENDMENT, ADOPTING FINDINGS PURSUANT TO THE CALIFORNIA ENVIRONMENTAL QUALITY ACT, AND ADOPTING A MITIGATION MONITORING AND REPORTING PROGRAM The City Council of the City of Seal Beach hereby finds and resolves as follows: Section 1. The project, known as the Department of Water and Power Specific Plan Amendment, are the proposed amendments to the 1996 Department of Water and Power ("DWP") Specific Plan that would allow for the development of 4.5 acres of residential development with 6.4 acres of open space and passive recreation uses on a total of 10.9-acres in the City of Seal Beach (the "City"). The project site currently consists of vacant land, portions of a residence and a commercial facility, and portions of the San Gabriel River and associated bike trail. The project site was formerly utilized by the Los Angeles DWP for power plant facilities and operations, and is generally bound by Marina Drive to the north, 1st Street to the east, the beach parking lot to the south, and the San Gabriel River to the west. Bay City Partners LLC (the "Applicant") has proposed to construct the residential subdivision in one phase that would include the finished pads and all infrastructures necessary to serve the new residential development. As originally proposed by the Applicant, the project would result in 48 single family residences located on approximately 4.5 acres with residential units to be developed individually by homeowners as custom homes with an expected twenty-four homes by the year 2014 and an additional twenty-four homes by the year 2015. The remaining approximately 6.4 acres would be used for open space and passive recreation uses. This project, in its entirety, requires a General Plan amendment, zone map amendment, DWP Specific Plan amendment, tentative tract map, and a lot line adjustment. The General Plan amendment, zone map amendment, and DWP Specific Plan amendment, if approved, would allow for the property to be developed with residential uses. The tentative tract map and lot line adjustment, if approved, would allow for the property to be subdivided into single-family parcels. An additional component would be the procurement, development and construction of infrastructure improvements. Necessary utilities include: water distribution system,wastewater system, storm water conveyance system, dry utilities (e.g., electricity and natural gas), and roads and sidewalks. All necessary utilities would be installed to the property line of the newly created residential lots. All utilities will be underground. The streets, alleys, and infrastructure all would be constructed to City standards and requirements. All streets would be dedicated to the City when the Final Tract Map is recorded, except for the proposed private driveways. Section 2. On June 7, 2011, a Notice of Preparation ("NOP") was distributed to the State Office of Planning and Research and responsible • agencies for a thirty-day period till July 6, 2011. In addition, a public scoping meeting was held on June 20, 2011 in the City of Seal Beach Council Chambers to provide information and to provide a forum where interested individuals, groups, public agencies and others could provide verbal input to the City on further refining the intended scope and focus of the Environmental Impact Report ("EIR"). • Section 3. On November 14, 2011, a Draft Environmental Impact Report (the "DEIR") was prepared and released for the original project. In . accordance with the•California Environmental Quality Act ("CEQA") (Cal. Pub. Res. Code §21000 et seq.) and the State Guidelines (the "Guidelines") (14 Cal. Resolution Number 6273 Code Regs. §15000 et seq.) promulgated with respect thereto, the City analyzed the project's potential impacts on the environment. Section 4. The City circulated the DEIR and the Appendices for the project to the public and other interested parties for an extended 57-day comment period, from November 14, 2011 to January 9, 2012, CEQA Guideline Section 15105 requires only a 45-day public comment period. Section 5. The City prepared written responses to all comments received on the DEIR and those responses to comments are incorporated into the Final Environmental Impact Report("Final EIR"). The Final EIR is comprised of the DEIR dated November 2011 and all appendices thereto,written responses to all comments received on the DEIR, the supplemental analysis completed for the refinements to the project as discussed below, and the Mitigation Monitoring Program. Section 6. On April 25, 2012, City's Environmental Quality Control Board ("EQCB") reviewed the Final EIR at a duly noticed public meeting. After taking public comment on the Final EIR, the EQCB voted to recommend that the City Council not certify the Final EIR. Section 7. On May 2, 2012,the City's Planning Commission held a duly noticed public hearing to consider the Final EIR and the project, during which the Applicant submitted a revised tract map to replace the original map. The revised map included the same number of lots in the subdivision but reoriented certain lots along First Street and realigned a proposed roadway to avoid the significant and unavoidable aesthetic impacts identified in the Final EIR. The Planning Commission continued the public hearing to permit City staff and the City's environmental consultant to review the revised map. On June 6, 2012, the Planning Commission held a duly noticed continued public hearing to consider the Final EIR and the project as refined by the Applicant's revised submittal. At this public hearing, the Planning Commission provided comments to the Applicant regarding the originally submitted tract map and the revised map. The • comments primarily focused on lot widths, drainage patterns/water quality features, pad elevations, and street/alley widths. After considering all the evidence presented at the continued public hearing, the Planning Commission adopted Planning Commission Resolution 12-9, recommending that the City Council certify the Final EIR, adopt findings, adopt the Mitigation Monitoring and Reporting Program, and approve the project, inclusive of the Applicant's revised tract map and subject to such additional conditions and recommendations specified in the resolution. Section 8. In response to the Planning Commission's recommendations, the Applicant subsequently further refined the project by submitting a second revised tract map.This second revised tract map refined the revised map and is identical to the tract map and site plan analyzed in the Final EIR in the following respects: same acreage for development (4.5); same acreage for open space (6.4); same construction phasing; same volume of cut and fill associated with site grading; same proposed vacation of triangular portion of 1st Street; and realignment of the intersection of Marina Drive and 1st Street. The differences of note between the second revised tract map and the tract map and site plan analyzed in the Final EIR Project are summarized in Section III of the attached exhibit A,which is hereby incorporated by this reference. Section 9. The City commissioned an environmental analysis of the second revised tract map by an independent environmental consultant, RBF Consulting. RBF Consulting prepared a document entitled Environmental Analysis of the Alternative Site Plan: Department of Water and Power Specific Plan Amendment dated June 15, 2012, which included a Hydrological and Hydraulic Narrative prepared by Fuscoe Engineering (June 13, 2012) and a Supplemental Traffic Assessment prepared by Linscott, Law & Greenspan Engineers (June 14, 2012), and is hereby incorporated by this reference. The analysis concluded that the second revised tract map would not result in greater Page 2 Resolution Number 6273 impacts than were identified for the project as originally analyzed in the DEIR, and that it would avoid the significant and unavoidable aesthetic impacts identified in the DEIR. It also concluded that DEIR Mitigation Measures TRA-2 through TRA-4, needed to be modified slightly to account for the changes to the roadway configuration in the second revised tract map, and revised those Mitigation Measures accordingly. However, these modifications were determined to not result in any new or greater impacts than those identified in the DEIR. Thus, no new impacts have been identified and no new mitigation measures are required for implementation of the second revised tract map. The City Council hereby finds in the exercise of its independent judgment that the conclusions of RBF Consulting are correct and the analysis was completed in full compliance with CEQA. Section 10. The project as analyzed in the Final EIR and as further refined by the second revised tract map hereinafter constitute the Project. Section 11. The findings made in this Resolution are based upon the information and evidence set forth in the Final EIR and upon other substantial evidence that has been presented at the hearings and in the record of the proceedings. The documents, staff reports, technical studies, appendices, plans, specifications, and other materials that constitute the record of proceedings on which this Resolution is based are on file for public examination during normal business hours at the City of Seal Beach, 211 8th Street, Seal Beach, California 90740. Each of these documents is incorporated herein by this reference. Section 12. The City Council finds that agencies and interested members of the public have been afforded ample notice and opportunity to comment on the EIR and the Project. Section 13. Section 15091 of the State CEQA Guidelines requires that the City, before approving the Project, make one or more of the following written finding(s) for each significant effect identified in the Final EIR accompanied by a brief explanation of the rationale for each finding: 1. Changes or alterations have been required in, or incorporated into, the project which avoid or substantially lessen the significant environmental effects as identified in the Final EIR; or, 2. Such changes or alterations are within the responsibility and jurisdiction of another public agency and not the agency making the finding. Such changes have been adopted by such other agency or can and should be adopted by such other agency;or, 3. Specific economic, legal, social, technological, or other considerations, including provision of employment opportunities for highly trained workers, make infeasible the mitigation measures or project alternatives identified in the final EIR. As shown in more detail in Exhibit A, attached hereto and incorporated herein by this reference, changes and alterations have been required in, or incorporated into,the project analyzed in the Draft EIR which avoid or substantially lessen the significant environmental effects as identified in the Final EIR. Section 14. Environmental impacts identified in the Initial Study to be less than significant and do not require mitigation are described in Section IV respectively of Exhibit A. Section 15. Environmental impacts identified in the Final EIR as less than significant and do not require mitigation are described in Section V respectively of Exhibit A. Page 3 Resolution Number 6273 Section 16. Environmental impacts identified in the Final EIR as significant but mitigable are described in Section VI respectively of Exhibit A. Section 17. Alternatives to the Project are described in Exhibit A, Section VIII,. Section 18. Public Resources Code section 21081.6 requires the City to prepare and adopt a mitigation monitoring and reporting program for any project for which mitigation measures have been imposed to assure compliance with the adopted mitigation measures. The Mitigation Monitoring and Reporting Program is attached hereto as Exhibit B, and is hereby incorporated herein by reference. Section 19. Prior to taking action, the City Council reviewed, considered and has exercised its independent judgment on the Final EIR and all of the information and data in the administrative record, and all oral and written testimony presented to it during meetings and hearings and finds that the Final EIR is adequate and was prepared in full compliance with CEQA. No comments or any additional information submitted to the City, including the supplemental analysis on the refinements to the Project, have produced any substantial new information requiring recirculation or additional environmental review of the Project under CEQA. Section 20. The City Council of the City of Seal Beach hereby certifies the Final EIR, adopts findings pursuant to the California Environmental Quality Act, as set forth in Exhibit A; adopts the Mitigation Monitoring and Reporting Program attached hereto as Exhibit B, and imposes each mitigation measure as a condition of Project approval. City staff shall implement and monitor the mitigation measures as described in Exhibit B. PASSED, APPROVED AND ADOPTED by the Seal Beach City Council at a regular meeting held on the 25th day of June ,2012 by the following vote: AYES: Council Members NOES: Council Members ABSENT: Council Members ABSTAIN: Council Members Mayor ATTEST: City Clerk STATE OF CALIFORNIA } COUNTY OF ORANGE ) SS CITY OF SEAL BEACH } I, Linda Devine, City Clerk of the City of Seal Beach, do hereby certify that the foregoing resolution is the original copy of Resolution Number 6273 on file in the office of the City Clerk, passed, approved, and adopted by the City Council at a regular meeting held on the 25th day of June ,2012. City Clerk Page 4 EXHIBIT A FINDINGS AND FACTS IN SUPPORT OF FINDINGS I. Introduction The California Environmental Quality Act ("CEQA") and the State CEQA Guidelines(the"Guidelines") provide that no public agency shall approve or carry out a project for which an environmental impact report has been certified which identifies one or more significant effects on the environment that will occur if a project is approved or carried out unless the public agency makes one or more of the following findings: A. Changes or alterations have been required in, or incorporated into, the project which avoid or substantially lessen the significant environmental effects identified in the EIR. B. Such changes or alterations are within the responsibility of another public agency and not the agency making the finding. Such changes have been adopted by such other agency or can and should be adopted by such other agency. C. Specific economic, social, or other considerations make infeasible the mitigation measures or project alternatives identified in the EIR.1 Pursuant to the requirements of CEQA, the City Council hereby makes the following environmental findings in connection with the proposed Department of Water and Power Specific Plan Amendment (the "Project"). These findings are based upon evidence presented in the record of these proceedings, both written and oral, the DEIR, and all of its contents, the Comments and Responses to Comments on the EIR, the supplemental analysis completed for the refinements to the Project, and staff and consultants' reports presented through the hearing process,which comprise the Final EIR("FEIR"). II. Project Objectives As set forth in the EIR, the proposed Project is intended to achieve a number of objectives (the"Project Objectives")as follows: • A. To create a high quality residential project that preserves the public views of the water. B. To design and build a residential neighborhood that extends the existing.urban form of the Old Town Neighborhood by replicating street layout, lot patterns, and building form. C. To enhance the open space and recreational opportunities for the residents of Seal Beach. D. To preserve public access to the beach through continued use of the San Gabriel River Bike Trail and 1s1 Street beach parking lot. E. To incorporate sustainable design and construction practices to the greatest degree practical. III. Background In response to the Planning Commission recommendations after public hearings held on May 2, 2012 and June 6, 2012, the Applicant incorporated refinements to the project through a second revised tract map that avoid or Cal.Pub.Res.Code§21081;14 Cal.Code Regs.§15091. Page 1 Resolution Number 6273 substantially lessen the significant environmental effects identified in the Draft EIR. The City commissioned an environmental analysis in full compliance with CEQA, of the refinements to the project. These refinements are identical to the tract map and site plan analyzed in the DEIR in the following respects. The refinements have the same acreage for development (4.5), same acreage for open space (6.4), same construction phasing, same volume of cut and fill associated with site grading, and the same proposed vacation of a triangular portion of 1st Street realignment of the intersection of Marina Drive and 1st Street. The refinements materially differ from the tract map and site plan analyzed in the DEIR in the following respects. • The second revised tract map proposes the majority of the lots to be front-facing along Marina Drive and 1st Street (with the exception of Lot 22). • The number of residential lots has been reduced from 48 to 32. • Residential lots range in size from 5,787 s.f. on Lot 28 to 3,144 s.f. on Lot 21. • The Lot widths vary from 55 feet(Lot 32)to 30 feet. • Frontages and rear lines vary due to street conditions, but the lot widths stated hold for the buildable areas. • Lot depths vary from 100 feet to 142 feet with the vast majority being in the 105 feet range. • No residential lots cross the northwesterly projection of the northeasterly right-of-way of Central Way. • Eight lots (Lots 14 through 21) front 1st Street. Lot 22 is side loaded to 1st Street. • Six lots front the San Gabriel River (five residential and one open space lot used for detention and water quality). • Streets "A", "B" and "C" are designated public streets and all have a right-of-way width of 52 feet consisting of a 5-foot sidewalk, 3-foot parkway, 8-foot parking lane, and a 10-foot drive aisle for each street half. Alleys are public. • Lots"F , "G and"H are common lots. • A 10-foot wide trail easement is located along the northeast line of Lot H. • The riverfront lots(Lots 28 through 32)are at least 50 feet wide. • Alley"E now extends through to Marina Drive. • Lots 8 through 27 have alley access. • Building pads along the river front have been lowered approximately 1 foot. • Building pads for Lots 1 through 8 have increased by approximately 6 inches. However, because these lots are substantially longer than average, it is anticipated that the rear yard areas facing Marina Drive can be graded to buffer the height difference between the building pad and right-of-way. Page 2 • 35 percent of the lots are greater than 37.5 feet. All the lots greater than 37.5 feet wide are 45 feet wide or greater. The remaining 65 percent are 30 foot wide lots. As provided throughout these findings, the refinements would alter the environmental conclusions in the DEIR by reducing environmental impacts. In particular, the previous significant and unavoidable impacts associated with long- term visual character and quality and long-term light and glare would be eliminated. As stated throughout these findings, these refinements also have the potential to further reduce impacts that have already been deemed less than significant with or without mitigation. No new or increased impacts are anticipated from these Project refinements. These refinements have not produced any substantial new information requiring recirculation or additional environmental review under CEQA. IV. Effects Determined to be Less Than Significant/No Impact in the Initial Study/Notice of Preparation The City of Seal Beach conducted a Notice of Preparation (NOP) and Initial Study to determine the potential environmental effects of the Project. In the course of this evaluation, the Project was found to have no impact in certain impact categories because a project of this type and scope would not create such impacts or because of the absence of project characteristics producing effects of this type. The following effects were determined not to be significant or to be less than significant for the reasons set forth in the Initial Study, and were not analyzed in the EIR because they require no additional analysis to determine whether the effects could be significant. The refinements to the Project, as described in Section III, do not change the conclusions of the Initial Study. A. AESTHETICS 1. The Project will not substantially damage scenic resources, including, but not limited to, trees, rock outcroppings, and historic buildings within a state scenic highway as no scenic resources such as trees or rock outcroppings exist on the Project site and the Project site does not lie within the viewshed of a state designated scenic highway. 2. The Project, combined with other related cumulative projects, will not cumulatively contribute to a significant construction light and glare impact. B. AGRICULTURAL RESOURCES 1. The Project will not convert prime farmland, or farmland of statewide importance to non-agricultural use because there are no agricultural resources on the Project site. 2. The Project will not conflict with existing zoning for agricultural use or a Williamson Act contract because the property is not zoned for agricultural use and is not subject to a Williamson Act contract. 3. The Project will not conflict with existing zoning for, or cause rezoning of forest land, timberland, or timberland zoned timberland production as the Project site is not zoned for these uses. 4. The Project will not result in the loss of forest land or conversion of forest land to non-forest use, as no forest land exists on the Project site. 5. The Project will not involve other changes in the existing environment that, due to their location or nature, could result in conversion of Farmland to non-agricultural use because there are no agricultural resources on the site or in the vicinity. Page 3 Resolution Number 6273 C. AIR QUALITY 1. The Project will not create objectionable odors as the proposed Project does not contain any operational uses associated with odors as determined by South Coast Air Quality Management District's CEQA Air Quality handbook. Additionally, construction odors would be intermittent and short-term and would not pose an impact. D. BIOLOGICAL RESOURCES 1. The Project will not conflict with any local policies or ordinances protecting biological resources. 2. The Project will not conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan, because there are no such plans that apply to the Project site. E. GEOLOGY AND SOILS 1. The Project will have a less than significant impact with regard to exposing people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving rupture of a known earthquake fault as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of a known fault. 2. The Project will have a less than significant impact with regard to exposing people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving landslides. F. HAZARDS AND HAZARDOUS MATERIALS 1. The Project will not create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials. 2. The Project will not emit hazardous emissions or handle hazardous or . acutely hazardous materials, substances, or waste within '/4 mile of an existing or proposed school. 3. The Project will not be located on a site which is included on a list of hazardous material sites as compiled pursuant to Government Code Section 65962.5. 4. The Project is not located within an airport land use plan or, where such plan has not been adopted, within two miles of a public airport or public use airport, and thus the Project would not result in a safety hazard for people residing in the Project area. 5. The Project is not located within the vicinity of a private airstrip. 6. The Project will not impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan. 7. The Project will not expose people or structures to a significant risk of loss, injury or death involving wildland fires, including where wildlands are subject to urbanized areas or where residences are intermixed with wildlands, because the site is not in or adjacent to wildland areas. Page 4 G. HYDROLOGY AND WATER QUALITY 1. The Project will not substantially deplete groundwater supplies or interfere substantially with groundwater recharge such that there would be a net deficit in aquifer volume or a lowering of the local groundwater table level. 2. The Project will not place housing within a 100-year flood hazard area as mapped on a federal Flood Hazard Boundary or Flood Insurance Rate Map or other flood hazard delineation map as the Project area is not within a 100-year flood zone. 3. The Project will not place structures within a 100-year flood hazard area that would impede or redirect flood flows, because the site is not in a flood hazard area. 4. The Project will not expose people or structures to a significant risk of loss, injury or death involving flooding, including flooding as a result of the failure of a levee or dam. H. LAND USE AND PLANNING 1. The Project will not physically divide an established community. 2. The Project will not conflict with an applicable habitat conservation plan or natural community conservation plan. MINERAL RESOURCES 1. The Project will not result in the loss of availability of a known mineral resource that would be of value to the region and the residents of the state. 2. The Project will not result in the loss of availability of a locally-important mineral resource recovery site delineated on a local general plan, specific plan or other land use plan. J. NOISE 1. The Project will not be located within an airport land use plan, or within two miles of a public airport or public use airport such that the Project would expose people residing or working in the Project area to excessive noise levels. 2. The Project will not be located within the vicinity of a private airstrip such • that it would expose people residing or working in the Project area to excessive noise levels. K. POPULATION AND HOUSING 1. The Project will not displace substantial numbers of existing housing, necessitating the construction of replacement housing elsewhere, as the Project site is mostly vacant. 2. The Project will not displace substantial numbers of people, necessitating the construction of replacement housing elsewhere, as the Project site is mostly vacant. L. TRANSPORTATION AND TRAFFIC 1. The Project will not result in a change in air traffic patterns, including either an increase in traffic levels or a change in location that results in substantial safety risks. Page 5 Resolution Number 6273 2. The Project will not result in inadequate emergency access as it is full compliance with the City's Municipal Code Section 10.40.010 regarding emergency access. V. Effects Determined to be Less Than Significant Without Mitigation in the EIR The EIR found that the proposed Project would have a less than significant impact without the imposition of mitigation on a number of environmental topic areas listed below. A less than significant environmental impact determination was made for each of the following topic areas listed below, based on the more expansive discussions contained in the FEIR. Further, the refinements to the Project described in Section III above do not change the following conclusions. A. LAND USE AND PLANNING 1. The Project will be consistent with the Coastal Act Planning and Management policies. 2. The Project will not conflict with the Southern California Association of Government's Regional Planning efforts. 3. The Project will not conflict with the Seal Beach General Plan policies or regulations, as amended. 4. The Project will not conflict with Seal Beach Municipal Code 10, Subdivisions, standards or regulations. 5. The Project will not conflict with Seal Beach Municipal Code 11, Zoning, standards or regulations. 6. The Project will not conflict with the DWP Specific Plan standards or regulations, as amended. 7. The Project, combined with other related cumulative projects, will not conflict with applicable land use plans, policies or regulations. B. AESTHETICS 1. The Project will not have a substantial effect on a scenic view or vista. • 2. The Project, combined with other related cumulative projects,will not have an adverse effect on a scenic vista. 3. The Project, combined with other related cumulative projects, will not degrade the visual character and quality of the development site and its surroundings. C. BIOLOGICAL RESOURCES 1. The Project will not have a project level or cumulative adverse effect, either directly, or through habitat modifications, on species identified as a candidate, sensitive, or special status. 2. The Project will not have a project level or cumulative adverse effect on riparian habitat or other sensitive natural community. 3. The Project will not have a project level or cumulative substantial adverse effect on jurisdictional waters or wetlands. 4. The Project will not have a cumulative impact on migratory birds or other species, but has the potential to have a project specific impact on migratory birds that will be reduced to less than significant as discussed in Section VI below. Page 6 D. CULTURAL RESOURCES 1. The Project will not cause a significant impact to a historical resource. 2. The Project, combined with other related cumulative projects, will not cause a significant impact to a historical resource. E. TRAFFIC AND CIRCULATION 1. The Project will not cause an increase in traffic for existing and forecast year 2015 traffic conditions when compared to the traffic capacity of the street system. 2. The Project, along with buildout of the Seal Beach General Plan in year 2030 conditions,will not result in significant traffic impacts. 3. The Project will not cause a significant increase in traffic for forecast year 2015 conditions at Caltrans intersections. • 4. The Project will not result in a decrease of the performance or safety of public transit, bicycle, or pedestrian facilities as a result of a conflict with adopted policies,plans or programs. 5. The Project, and other related cumulative projects, will not cause an increase in traffic for existing and forecast year 2015 traffic conditions when compared to the traffic capacity of the street system. 6. The •Project, and other related cumulative projects, in year 2030 conditions,will not result in significant traffic impacts. 7. The Project, along with other related cumulative projects, will not cause a significant increase in traffic for forecast year 2015 conditions at Caltrans intersections. 8. The Project, along with other related cumulative projects, will not result in a decrease of the performance or safety of public transit, bicycle, or pedestrian facilities as a result of a conflict with adopted policies, plans or programs. F. AIR QUALITY 1. The Project will not result in significant impacts pertaining to operational air emissions. 2. The Project, along with cumulative projects, will not result in significant cumulative impacts pertaining to operational air emissions. 3. The Project will not cumulatively contribute to impacts associated with consistency with the South Coast Air Quality Management District's 2007 Air Quality Management Plan. G. GREENHOUSE GAS EMISSIONS 1. The Project will not have a significant impact on global climate change. 2. The Project will not conflict with an applicable greenhouse gas reduction plan, policy or regulation. H. NOISE 1. The Project will not result in significant vibration impacts to nearby sensitive receptors. 2. Traffic generated by the Project will not significantly contribute to existing traffic noise in the area or exceed the City's established standards. Page 7 Resolution Number 6273 3. The Project will not result in a significant increase in long-term stationary ambient noise levels. 4. The Project, in conjunction with other cumulative projects, will not contribute to a cumulative vibration impact. 5. The Project will not contribute to a cumulative traffic noise impact that exceeds the City's established standards. 6. The Project will not contribute to a significant increase in cumulative long- term stationary ambient noise levels. GEOLOGY AND SOILS 1. The Project will not expose people or structures to potential substantial adverse effects involving strong seismic ground shaking. 2. The Project will not result in substantial soil erosion or the loss of topsoil. 3. The Project, combined with other related cumulative projects, will not expose people or structures to substantial adverse effects involving strong seismic ground shaking. 4. The Project, combined with other related cumulative projects, will not result in substantial soil erosion or the loss of topsoil. J. HYDROLOGY AND WATER QUALITY 1. The Project will not expose people or structures to a significant risk of loss, injury or death involving inundation by seiche, tsunami, or mudflow, because the site is sufficiently removed from large bodies of water, and is not near any sloped properties. 2. The Project will not cumulatively expose people or structures to a significant risk of loss, injury or death involving inundation by seiche, tsunami, or mudflow. K. POPULATION AND HOUSING 1. The Project will not induce substantial population growth in the City, either at the project level or on cumulative basis. 2. The Project will not displace housing and persons necessitating the construction of replacement housing elsewhere, either at the project level or on a cumulative basis. L. PUBLIC SERVICES AND UTILITIES 1. The Project will not result in the need for additional police protection facilities and personnel, either on a project specific level or on a cumulative basis. 2. The Project will not result in the need for additional school facilities, either on a project specific level or on a cumulative basis, as the Project will need to comply with applicable school fee requirements. 3. The Project will not require new parkland in order to maintain acceptable service ratios, either on a project specific level, or on a cumulative basis. 4. The Project will not increase the use of existing recreational facilities, causing their physical deterioration, either on a project specific level, or on a cumulative basis. Page 8 5. The Project's proposed recreational facilities will not adversely impact the environment. 6. The Project will not significantly increase the demand for water, on a project specific level, or on a cumulative basis, such that new entitlements or water resources are needed. 7. The Project will not generate solid waste that exceeds the permitted capacity of the landfill serving the City, either on a project specific level, or on a cumulative basis. 8. The Project will comply with all state and local statutes and regulations related to solid waste. 9. The Project will not result in significant impacts, either on a project specific level or cumulative basis, related to any other public facilities, such as libraries, electricity, natural gas or telephone services. VI. Potentially Significant Environmental Impacts Determined to be Mitigated to a Less Than Significant Level The EIR identified the potential for the project to cause significant environmental impacts in the areas of land use and relevant planning, aesthetics/light and glare, biological resources, cultural resources, traffic and circulation, air quality, greenhouse gas emissions, noise, geology and soils, hazards and hazardous materials, hydrology and water quality, population and housing, and public services and utilities. Mitigation measures are identified that would mitigate all of these impacts to a less than significant level. The City Council finds that the feasible mitigation measures identified in the FEIR would reduce the Project's impacts to a less than significant level. Further, the refinements to the Project would reduce the previous significant and unavoidable impacts associated with long term visual character and quality and long-term light and glare to less than significant levels. The City Council will adopt all of the feasible mitigation measures for the Project described in the FEIR as conditions of approval of the Project and incorporate those into the Project if approved. A. AESTHETICS 1. Visual Character and Quality—Construction Impact Project construction activities would temporarily degrade the visual character and quality of the site and its surroundings. However, with the • implementation of mitigation, this impact will be reduced to a less than significant level. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential construction visual character and quality impact. Specifically, the following mitigation measure is imposed upon the Project to ensure a less than significant impact: AES-1 Prior to issuance of any grading and/or demolition permits, whichever occurs first, a Construction Management Plan shall be submitted for review and approval by the Director of Development Services. The Construction Management Plan shall, at a minimum, indicate the equipment and vehicle staging areas, stockpiling of materials, fencing (i.e., temporary fencing with opaque material), and haul route(s). Staging areas shall be sited and/or screened in order to minimize public views to the maximum Page 9 Resolution Number 6273 extent practicable. Construction haul routes shall minimize impacts to sensitive uses in the City. b. Facts in Support of Findings Surrounding sensitive receptors that would have views for a long duration of the Project site during construction include multi-family residential uses (River Beach Townhomes by the Sea) to the north and single-family residential uses to the east. Sensitive receptors that would have moderate and short duration views would include recreational users at Windsurf Park, River's End Staging Area (RESA), and the San Gabriel River Greenbelt, as well as motorists traveling along Marina Drive and 1st Street. Construction-related activities would temporarily influence the character of the Project site, as viewed from surrounding sensitive viewers. During construction, the various construction activities would intermittently alter the character of the Project site and its surroundings. Graded surfaces, construction debris, construction equipment, and truck traffic would be visible. Additionally, soil would be stockpiled and equipment for grading activities would be staged at various locations throughout the northern portion of the Project site. Adjoining residents would have direct views of the Project's construction activities, which would visibly degrade the character for this area. Mitigation Measure AES-1 would require the preparation of a Construction Management Plan, which specifies requirements for equipment and vehicle staging areas, stockpiling of materials, fencing (i.e., temporary fencing with opaque material), and haul route(s). All staging areas would be required to be sited and screened in a manner that would minimize public views and views from surrounding residents to the staging areas. Implementation of Mitigation Measure AES-1 would minimize the visual impacts, as viewed by the surrounding residents and motorists. Upon completion of construction of the proposed site that includes grading and pad preparation, individual home owners would then construct homes on the graded pads at the site. Construction of the 48 residential structures is anticipated to occur over approximately two years. However, as structures are erected on-site, they would screen views to on-site construction activities during this time. As these impacts are temporary in nature and would cease upon Project completion, the Project's construction-related impacts to the visual character or quality of the site and its surroundings would be reduced to less than significant levels with implementation of Mitigation Measure AES-1. 2. Light and Glare—Construction Impact Short-term construction light and glare impacts will result during the nighttime hours from lighting associated with Project construction. However,with the implementation of mitigation below, this impact will be reduced to a level of insignificance. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential construction light and glare impact. Specifically, the following mitigation measure is imposed upon the Project to ensure a less than significant impact: AES-2 All construction-related lighting shall be located and aimed away from adjacent residential areas and consist of the minimal wattage necessary to provide safety and security at the construction site. A Construction Safety Lighting Plan shall be approved by the City Engineer prior to issuance of the grading permit application. Page 10 b. Facts in Support of Findings Short-term light and glare impacts associated with construction activities would likely be limited to nighttime lighting (for safety and security purposes) in the evening hours. In accordance with Title 7, Public Peace, Morals and Welfare, of the Municipal Code, noise associated with the Project's construction activities would be limited to the hours of 7:00 a.m. and 8:00 p.m. on weekdays and between 8:00 a.m. and 8:00 p.m. on Saturday. Noise associated with construction activities is prohibited on Sundays. Therefore, as the construction noise activities would cease at 8:00 p.m., inherently, the construction-related light and glare would also cease at 8:00 p.m. Construction staging areas may also require security lighting for equipment stored on-site. In order to minimize any potential light/glare impacts to sensitive uses, all construction-related lighting would be down directed and oriented away from adjacent residential areas and would consist of the minimal wattage necessary to provide safety at the construction site pursuant to Mitigation Measure AES-2. Impacts in this regard would be reduced to less than significant upon implementation of the City's Municipal Code requirements and the recommended Mitigation Measure AES-2. Thus, impacts would be less than significant. 3. Light and Glare Long-Term Cumulative Impact The Project, coupled with other cumulative Projects, has the potential to result in a cumulative light and glare impact. However, with mitigation, this impact will be eliminated. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential cumulative light and glare impact. Specifically, the following mitigation measure is imposed upon the Project to ensure a less than significant impact: AES-3 The project applicant shall ensure that any proposed exterior lighting fixtures,with respect to both the direction of lighting and its intensity in the private right of way and on private property, do not result in lighting spill over onto the adjacent uses. The project applicant shall prepare and submit an Outdoor Lighting Plan for both street lights and future residential uses to the Development Services Department for review and approval, prior to issuance of a grading permit. The Plan shall demonstrate compliance with all applicable Code lighting requirements and include a footcandle map illustrating the amount of light from the project site at adjacent light sensitive receptors. All exterior light fixtures (including street lighting) shall be shielded or directed away from adjoining uses. Landscape lighting levels shall respond to the type, intensity, and location of use. b. Facts in Support of Findings Light sources associated with the Project would include new street lights, security lights, and interior lights, which may create light spillover and glare impacts on surrounding land uses in the absence of mitigation. Implementation of the proposed Project previously resulted in a significant and unavoidable impact to residential uses to the east as a result of vehicle headlights exiting the Project site at the intersection of B' Street and 1St Street. However, this impact was eliminated based on the Project refinements discussed in Section III above. Page 11 Resolution Number 6273 The Project would cumulatively contribute to the creation of new lighting in the general area. However, due to the distance between the cumulative project locations and the existing urban lighting that occurs within the City, the Project's cumulative contribution would be minimal. Upon implementation of Mitigation Measure AES-3, long-term (operational) light and glare impacts would be further reduced. Thus, implementation of the proposed Project would not cumulatively contribute to significant light/glare impacts with implementation of Mitigation Measure AES-3. Impacts in this regard would be reduced to less than significant levels. 4. Long-Term Visual Character and Quality Project implementation has the potential to degrade the visual character and quality of the site and its surroundings. However, with refinements to the Project discussed in Section III of these findings, these impacts have been avoided. a. Findings Changes or alterations have been required in, or incorporated into, the project which avoid or substantially lessen the significant environmental impacts to the long term visual character and quality of the environment identified in the Final EIR. b. Facts in Support of Findings Project implementation would alter the visual character of the site and its surroundings, as the existing vacant land and residential structure would be replaced with 32 residential structures and associated infrastructure in the northern portion of the site and passive park/open space uses within the southern portion of the site. The future residential uses at the Project site would be restricted to a maximum building height of 25 feet and maximum lot coverage of 75 percent, and thus would be similar in building height, massing, and scale to the existing residential structures to the east. The visual character and quality of Old Town Seal Beach is established through minimum 25-foot lots with frontage along the roadway and garage access provided through the rear yards and alleys. This supports the pedestrian scale that is desired for Old Town (the project area). Based upon the Planning Commission recommendations, the Applicant incorporated refinements to the Project that avoid or substantially lessen the significant environmental effects identified in the Draft EIR as discussed in Section III of these findings. As the refinements consist of a reduced number and realignment of the residential structures to be constructed, so that all but one of the lots adjacent to 1st Street will face 1st Street, implementation of the Project would be visually compatible with the character of the residential uses to the east of the Project site and would not alter the neighborhood's pedestrian scale and appearance. Thus, impacts in this regard that the Final EIR identified as significant and unavoidable have been avoided by changes made to the Project. 5. Long-Term Light and Glare Light sources associated with the operational phase of the Project have the potential to cause a significant impact. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential long term light and glare impact. Specifically, the following mitigation measure is imposed upon the Project to ensure a less than significant impact: AES-3 The project applicant shall ensure that any proposed exterior lighting fixtures,with respect to both Page 12 the direction of lighting and its intensity in the private right of way and on private property, do not result in lighting spill over onto the adjacent uses. The project applicant shall prepare and submit an Outdoor Lighting Plan for both street lights and future residential uses to the Development Services Department for review and approval, prior to issuance of a grading permit. The Plan shall demonstrate compliance with all applicable Code lighting requirements and include a footcandle map illustrating the amount of light from the project site at adjacent light sensitive receptors. All exterior light fixtures (including street lighting) shall be shielded or directed away from adjoining uses. Landscape lighting levels shall respond to the type, intensity, and location of use. b. Facts in Support of Findings Light sources associated with the Project would include new street lights, security lights, and interior lights, which may create light spillover and glare impacts on surrounding land uses in the absence of mitigation. Mitigation Measure AES-3 would ensure that all street lighting would utilize directional lighting techniques (without compromising site safety or security) that direct light downwards and minimize light spillover onto adjacent light sensitive receptors. The Project Applicant would be required to prepare and submit an Outdoor Lighting Plan that includes a footcandle map illustrating the amount of light from the Project site at adjacent light sensitive receptors. Landscape lighting levels would be required to respond to the type, intensity, and location of use. Lighting requirements for the safety and security of pedestrians and vehicular movements would be anticipated. Implementation of Mitigation Measure AES-3 would ensure that long-term (operational) light and glare impacts as a result of street lighting, security lights, and interior lights would be reduced to less than significant levels. Other sources of new lighting would include vehicle headlights entering and exiting the Project site. Implementation of the proposed Project would develop 'A' Street and 'B' Street. 'A' Street would terminate at Marina Drive, directly across from the parking lot uses and associated ornamental landscaping within the Townhomes by the Sea. The nearest residence would be approximately 100 feet away and would not be anticipated to be directly impacted by vehicle headlights exiting the Project site (as these structures are separated from the Project site by Marina Drive, associated landscaping, and. parking lot uses. . As originally proposed and analyzed in the Final EIR, 'B' Street would have terminated at 1st Street, directly across from existing residential structures (approximately 60 feet away). The existing structures include three-foot perimeter fencing and ornamental landscaping, which would have partially obstructed direct headlights from each of the residences. However, the lighting effect on these sensitive receptors would still have been significant. In response to Planning Commission recommendations, the Applicant proposed refinements to the Project as discussed in Section III of these findings which include realignment'B' Street so that it is aligned with Central Way. Thus, vehicles exiting the project site at the intersection of "B" Street and 1st Street would no longer direct vehicle headlights into surrounding residential structures. Thus, impacts in this regard that the Draft EIR identified as significant and unavoidable have been avoided by changes made to the Project. Page 13 Resolution Number 6273 B. BIOLOGICAL RESOURCES 1. Migratory Birds/Species—Project Specific Impact Implementation of the Project could interfere with the movement of a native resident or migratory species, and in particular migratory birds. However, with the implementation of mitigation, this impact will be reduced to a level of insignificance. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific migratory bird impact. Specifically, the following mitigation measure is imposed upon the Project to ensure a less than significant impact: BIO-1 To the extent feasible, all vegetation removal activities shall be scheduled outside of the nesting season (typically February 15 to August 15) to avoid potential impacts to nesting birds. However, if initial vegetation removal occurs during the nesting season, all suitable habitat shall be thoroughly surveyed for the presence of nesting birds by a qualified biologist prior to commencement of clearing. If any active nests are detected, a buffer of at least 100 feet (300 feet for raptors) shall be delineated, flagged, and avoided until the nesting cycle is complete as determined by the City. b. Facts in Support of Findings The Project site has the potential to support migratory bird species, including both raptor and songbird species. Disturbing or destroying active nests is a violation of the Federal Migratory Bird Treaty Act. Nesting activity typically occurs from mid-February to mid-August. The removal of vegetation during the breeding season is considered a potentially significant impact. Therefore, the Project would be required to comply with Mitigation Measure BIO-1, which would be accomplished in one of two ways. First, efforts would be made to schedule all vegetation removal activities outside of the nesting season (typically February 15 to August 15) to avoid potential impacts to nesting birds. This would ensure that no active nests would be disturbed and that habitat removal could proceed rapidly. Second, if initial vegetation removal occurs during the nesting season, all suitable habitat would be thoroughly surveyed for the presence of nesting birds by a qualified biologist before commencement of clearing. If any active.nests are detected, a buffer of at least 100 feet (300 feet for raptors) would be delineated, flagged, and avoided until the nesting cycle is complete, as determined by the biological monitor, to minimize impacts. Therefore, with the implementation of Mitigation Measure BIO-1, impacts to migratory birds would be reduced to less than significant levels. C. CULTURAL RESOURCES 1. Archeological Resources The Project has the potential to cause a significant impact to unknown archeological resources that could exist on the Project site. The implementation of mitigation will reduce this potential impact to a less than significant level. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential archeological resources impact. Specifically, the following mitigation measure is imposed upon the Project to ensure a less than significant impact: Page 14 CUL-1 An archaeologist and a Native American Monitor appointed by the City of Seal Beach shall be present during earth removal or disturbance activities related to rough grading and other excavation for utilities. If any earth removal or disturbance activities result in the discovery of cultural resources, the Project proponent's contractors shall cease all earth removal or disturbance activities in the vicinity and immediately notify the City selected archaeologist and/or Native American Monitor, who shall immediately notify the Director of Development Services. The City selected archaeologist shall evaluate all potential cultural findings in accordance with standard practice, the requirements of the City of Seal Beach Cultural Resources Element, and other applicable regulations. Consultation with the Native American Monitor, the Native American Heritage Commission, and data/artifact recovery, if deemed appropriate, shall be conducted. b. Facts in Support of Findings Although there are no previously recorded cultural resources located within the Project area, there are previously recorded cultural resources located within a 0.5-mile radius of the Project area. Further, the Native American scoping indicated the Project area is highly sensitive for cultural resources important to Native Americans. However, no archaeological resources were observed during the intensive-level survey of the Project area. The Project would allow for the development of a 48-lot residential development located on approximately 4.5 acres in the northern portion of the Project site and open space/passive recreation uses on the remaining approximately 6.4 acres of the Project site. As proposed, the Project would involve finished pads and all infrastructure necessary to serve the new residential development. The residential units would be developed individually by homeowners as custom homes. Although there are no known archaeological resources occurring at the Project site, the proposed Project does have the potential to impact previously unrecorded cultural resources during ground disturbances. An archaeologist and a Native American Monitor appointed by the City of Seal Beach would be required to be present during earth removal or disturbance activities related to rough grading and other excavation for utilities (Mitigation Measure CUL-1). If any earth removal or disturbance activities result in the discovery of cultural resources, the contractor(s) would cease all earth removal or disturbance activities in the vicinity and immediately notify the City selected archaeologist and/or Native American Monitor, who would immediately notify the Director of Development Services. The City selected archaeologist would then evaluate all potential cultural findings in accordance with standard practice, the requirements of the City of Seal Beach Cultural Resources Element, and other applicable regulations. Consultation with the Native American Monitor, the Native American Heritage Commission, and data/artifact recovery, if deemed appropriate,would also be conducted. With implementation of Mitigation Measure CUL-1, Project implementation would not cause a substantial adverse change in the significance of an archaeological resource and any potential impact would be less than significant. 2. Paleontological Resources The proposed Project has the potential to cause a significant impact to unknown paleontological resources that could occur on the Project site. With the Page 15 Resolution Number 6273 implementation of mitigation, any potential impact would be reduced to a level of insignificance. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential paleontological resources impact. Specifically, the following mitigation measure is imposed upon the Project to ensure a less than significant impact: CUL-2 An Orange County Certified Paleontologist appointed by the City of Seal Beach shall prepare a Paleontological Resource Monitoring and Mitigation Program prior to earth removal or disturbance activities at the project site. The City selected paleontologist shall be present during earth removal or disturbance activities related to rough grading and other excavation for utilities. Paleontological monitoring shall include inspection of exposed rock units during active excavations within sensitive geologic sediments. If any earth removal or disturbance activities result in the discovery of paleontological resources, the Project proponent's contractors shall cease all earth removal or disturbance activities in the vicinity and immediately notify the City selected paleontologist who shall immediately notify the Director of Development Services. The City selected paleontologist shall evaluate all potential paleontological findings in accordance with the Paleontological Resource Monitoring and Mitigation Program Monitoring, standard practice, the requirements of the City of Seal Beach Cultural Resources Element, and other applicable regulations. Upon completion of the fieldwork, the City selected paleontologist shall prepare a Final Monitoring and Mitigation Report to be filed with the City and the repository to include, but not be limited to, a discussion of the results of the mitigation and monitoring program, an evaluation and analysis of the fossils collected (including an assessment of their significance, age, geologic context), an itemized inventory of fossils collected, a confidential appendix of locality and specimen data with locality maps and photographs, and an appendix of curation agreements and other appropriate communications. b. Facts in Support of Findings Although no recorded vertebrate fossil localities occur within the Project area, at least five vertebrate localities have been recorded nearby in the same or similar geologic deposits that occur in the Project area. All fossil localities were discovered within older Quaternary deposits (i.e., Pleistocene-age deposits). The Project site is, in part, underlain by geologic deposits determined to have a high paleontological sensitivity. Thus, any Project-related ground disturbance (mass grading, excavation, and/or trenching) within Pleistocene marine terrace deposits or the Palos Verdes Sand could result in significant adverse impacts to paleontological resources unless mitigated. Ground disturbances in topsoil or Holocene alluvium and colluviums would not require full-time monitoring, as these sediments are not determined to have a paleontological sensitivity. However, an Orange County Certified Paleontologist appointed by the City of Seal Beach would be required to be prepare a Page 16 Paleontological Resource Monitoring and Mitigation Program and be present during earth removal or disturbance activities related to rough grading and other excavation for utilities occurring within paleontological sensitive Pleistocene marine terrace deposits or Palos Verdes Sand (Mitigation Measure CUL-2). If any earth removal or disturbance activities result in the discovery of paleontological resources, the contractor(s) would cease all earth removal or disturbance activities in the vicinity and immediately notify the City selected paleontologist, who would immediately notify the Director of Development Services. The City selected paleontologist would then evaluate all potential paleontological findings in accordance with standard practice, the requirements of the City of Seal Beach Cultural Resources Element, and other applicable regulations. The paleontologist would prepare a Final Monitoring and Mitigation Report, documenting the results of the mitigation and monitoring program and itemizing the fossils collected. With implementation of Mitigation Measure CUL-2, potential adverse impacts to paleontological resources would be reduced to a less than significant level. 3. Unknown Burial Sites The Project has the potential to cause a significant impact to unknown Native American burial sites that may exist on the Project site. However, mitigation is being imposed to ensure any potential impact is reduced to a level of insignificance. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential unknown burial sites impact. Specifically, the following mitigation measures are imposed upon the Project to ensure a less than significant impact: CUL-3 Should any human bone be encountered during any earth removal or disturbance activities, all activity shall cease immediately and the City selected archaeologist and Native American monitor shall be immediately contacted, who shall then immediately notify the Director of Development Services. The Director of Development Services shall contact the Coroner pursuant to Sections 5097.98 and 5097.99 of the Public Resources Code relative to Native American remains. Should the Coroner determine the human remains to be Native American, the Native American Heritage Commission shall be contacted pursuant to Public Resources Code Section 5097.98. CUL-4 If more than one Native American burial is encountered during any earth removal or disturbance activities, a "Mitigation Plan" shall be prepared and subject to approval by the City of Seal Beach Development Services Department. The Mitigation Plan shall include the following procedures: Continued Native American Monitoring Y All ground disturbance in any portions of the project area with the potential to contain human remains or other cultural material shall be monitored by a Native American representative of the Most Likely Descendant (MLD). Activities to be monitored shall include rough grading and grading of previously Page 17 Resolution Number 6273 undisturbed deposit, with the exception of contexts that are clearly within undisturbed soil profiles. • Exposure and removal of each burial shall be monitored by a Native American. Where burials are clustered and immediately adjacent, one monitor is sufficient for excavation of two adjoining burials. • Excavation of test units shall be monitored. Simultaneous excavation of two test units if less than 20 feet apart may be monitored by a single Native American. • If screening of soil associated with burials or test units is done concurrently with and adjacent to the burial or test unit, the Native American responsible for that burial or test unit will also monitor the screening. If the screening is done at another location, a separate monitor shall be required. • All mechanical excavation conducted in deposits that may contain human remains(i.e., all areas not completely within undisturbed soil profiles) shall be monitored by a Native American. Notification Procedures for New Discoveries • When possible burials are identified during monitoring of mechanical excavation, or excavation of test units, the excavation shall be temporarily halted while the find is assessed in consultation with the lead field archaeologist. If the find is made during mechanical excavation, the archaeologist or Native American monitoring the activity shall have the authority to direct the equipment operator to stop while the find is assessed. If it is determined that the find does not constitute a burial, the mechanical excavation shall continue. • If the find is determined to be a human burial, the lead archaeologist shall immediately notify the Site Supervisor for the developer, as well as the Principal Investigator. The Principal Investigator shall immediately notify the MLD and the Director of Development Services for the City of Seal Beach. Identification of Additional Burials • For all discovered human burials, attempts shall continue to be made to locate additional burials nearby through hand excavation techniques. This shall be done through the excavation of 1 x 1 meter exploratory test units (ETUs) placed along transects extending radially from each identified burial or burial cluster. The spacing of the ETUs shall be determined upon consultation with the Project Page 18 Archaeologist and the MLD. The radial transects shall be designed to test areas within 50 feet (15 meters) from the edge of each burial or burial cluster. Excavation of these units shall be limited to areas containing intact cultural deposit (i.e., areas that have not been graded to the underlying undisturbed soil profiles) and shall be excavated until the undisturbed soil profiles are encountered, or to the excavation depth required for the approved grading plan. The soil from the ETUs along the radial transects shall be screened only if human remains are found in that unit. • Controlled grading shall be conducted within these 50-foot heightened investigation areas with a wheeled motor grader.The motor grader shall use an angled blade that excavates 1 to 2 inches at a pass, pushing the soil to the side to form a low windrow. Monitors shall follow about 20 feet behind the motor grader, examining the ground or evidence of burials. • When a burial is identified during controlled grading, the soil in windrows that may contain fragments of bone from that burial shall be screened. At a minimum this shall include the soil in the windrow within 50 feet of the burial in the direction of the grading. • If additional burials are found during controlled grading, additional ETUs will be hand excavated in the radial patterns described above. Burial Removal and Storage • Consultation with the MLD shall occur regarding the treatment of discovered human burials. If the MLD determines it is appropriate to have discovered human remains pedestaled for removal, that activity shall be conducted in a method agreed to by the MLD. • After pedestaling or other agreed upon burial removal program is completed, the top of a burial shall be covered with paper towels to act as a cushion, and then a heavy ply plastic will be placed over the top to retain surface moisture. Duct tape shall be wrapped around the entire pedestal, securing the plastic bag and supporting the pedestal. Labels shall be placed on the plastic indicating the burial number and the direction of true north in relation to the individual burial. Sections of rebar shall be hammered across the bottom of the pedestal and parallel to the ground. When a number of parallel rebar sections have been placed this way, they shall be lifted simultaneously, cracking the pedestal loose from the ground. The pedestal shall then be pushed onto a thick plywood board and lifted onto a pallet.A forklift shall carry the pallet to a Page 19 Resolution Number 6273 secure storage area or secure storage containers located on the subject property. • If another agreed upon burial removal program is utilized, that method shall be carried out in a manner agreed upon after consultation with the MLD and concurrence by the Director of Development Services. Study of Burial Remains • If the burials are removed in pedestal and are incompletely exposed, osteological studies are necessarily limited to determination (if possible) of age, sex, position, orientation, and trauma or pathology. After consultation, and only upon written agreement by the MLD, additional studies that are destructive to the remains may be undertaken, including radiocarbon dating of bone or DNA studies. If the MLD determines that only non-destructive additional studies may be allowed, one shell may be removed from each burial and submitted for radiocarbon dating. The assumption here is that the shell would have been part of the fill for the burial pit, and therefore would provide a maximum age for the burial. • The MLD may indicate a willingness to consider some additional exposure and study of the skeletal material removed from the sites. Such study would not involve removal of the remains from the project area, but rather would be undertaken near the storage area. To the extent allowed by the MLD, the bones would be further exposed within the existing pedestals or other medium containing the human remains and additional measurements taken. Consultation with the MLD regarding the feasibility of these additional studies prior to reburial would occur. Repatriation of Burials and Associated Artifacts • Once all portions of the project area have been graded to the underlying culturally sterile marine terrace deposits, or to the excavation depth required for the approved grading plan, the repatriation process shall be initiated for all recovered human remains and associated artifacts. Once a reburial site has been identified and prepared, the remains and associated artifacts shall be transported from the secure storage area to the site for reburial. Appropriate ceremony will be undertaken during this process at the discretion of the MLD. Additional Studies Considerable additional data relating to regional research issues may be uncovered if substantial Page 20 numbers of human burials and other archaeological features are encountered during the construction monitoring for the development. If this occurs, additional analysis shall be conducted. The analysis shall be designed to more completely address the research issues discussed in the approved "Research Design," and to provide additional mitigation of impacts to the sites in light of the new finds. The following studies would be potentially applicable: • Radiocarbon Dating. In considering the implications of the burials in interpreting site use and regional settlement, it is critical to assess the time range represented by the interments. Do they correspond to the full temporal range of site use, or only a limited timeframe?Although direct dating of the bones may not be possible due to the destructive nature of the radiocarbon technique, the MLD may approve the removal of a single shell from the interior of each burial for dating. Although this shall not provide a direct date of the burial, assuming the shell was part of the burial fill it should provide a maximum age (that is, the burial should not be older than the shell). In addition, an equivalent number of additional samples from non-burial contexts would also be taken for comparative purposes. These data would provide a more secure measure of the intensity of occupation during different periods. • Animal Interments. Animal interments may be discovered within the project area. Because these are not human remains, somewhat more intensive study is possible. Because these features are uncommon and represent very culture-specific religious practices, they are useful in reconstructing cultural areas during certain times in prehistory. Analysis of animal interments will include: (1) exposure to determine burial position; (2) photo documentation; (3) examination of skeleton for age/sex; traumatic injury, pathology, butchering, or other cultural modification; (4) radiocarbon dating; and (5) examination of grave dirt for evidence of grave goods or stomach contents. Curation Cultural materials recovered from the cultural resources monitoring and mitigation program for the development shall be curated either at an appropriate facility in Orange County, or, in consultation with the City,at the San Diego Archaeological Center. Preparation of Final Report The final technical report shall be prepared and submitted to the City within 12 months of the completion of the archeological field work. The report shall conform to the guidelines developed by the California Office of Historic Preservation for Page 21 Resolution Number 6273 Archaeological Resource Management Reports (ARMR). It will be prepared in sufficient quantity to distribute to interested regional researchers and Native American groups. It shall thoroughly document and synthesize all of the findings from all phases of the cultural resources program. Funding shall be provided by the landowner. b. Facts in Support of Findings The Native American scoping indicated the Project area is highly sensitive for cultural resources important to Native Americans. Although there are no known Native American burial sites occurring at the Project site, the proposed Project does have the potential to impact previously unrecorded human remains during ground disturbances. Should any human bone be encountered during any earth removal or disturbance activities, all activity shall cease immediately and the City selected archaeologist and Native American monitor shall be immediately contacted, who shall then immediately notify the Director of Development Services pursuant to Mitigation Measure CUL-3. The Director of Development Services shall contact the Coroner pursuant to Sections 5097.98 and 5097.99 of the Public Resources Code relative to Native American remains. Should the Coroner determine the human remains to be Native American, the Native American Heritage Commission shall be contacted pursuant to Public Resources Code Section 5097.98. Also, if more than one Native American burial is encountered during any earth removal or disturbance activities, a "Mitigation Plan" would be required to be prepared and subject to approval by the City of Seal Beach Development Services Department as specified in Mitigation Measure CUL-4. Upon implementation of the recommended Mitigation Measures CUL-3 and CUL-4, potential impacts resulting from the alteration of human remains would be reduced to less than significant levels. 4. Cumulative Impacts to Archeological Resources, Paleontological Resources,and Unknown Burial Sites The Project, combined with other related cumulative projects, has the potential to cause a cumulative impact on archeological resources, paleontological resources, and unknown burial sites. However, project specific mitigation will ensure that any potential cumulative impact is reduced to a level of insignificance. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential cumulative impact. Specifically, the following mitigation measures are imposed upon the Project to ensure a less than significant impact: • CUL-1 An archaeologist and a Native American Monitor appointed by the City of Seal Beach shall be present during earth removal or disturbance activities related to rough grading and other excavation for utilities. If any earth removal or disturbance activities result in the discovery of cultural resources, the Project proponent's contractors shall cease all earth removal or disturbance activities in the vicinity and immediately notify the City selected archaeologist and/or Native American Monitor, who shall immediately notify the Director of Development Services. The City selected archaeologist shall evaluate all potential cultural findings in accordance with standard practice, the requirements of the City of Page 22 Seal Beach Cultural Resources Element, and other applicable regulations. Consultation with the Native American Monitor, the Native American Heritage Commission, and data/artifact recovery, if deemed appropriate, shall be conducted. CUL-2 An Orange County Certified Paleontologist appointed by the City of Seal Beach shall prepare a Paleontological Resource Monitoring and Mitigation Program prior. to earth removal or disturbance activities at the project site. The City selected paleontologist shall be present during earth removal or disturbance activities related to rough grading and other excavation for utilities. Paleontological monitoring shall include inspection of exposed rock units during active excavations within sensitive geologic sediments. If any earth removal or disturbance activities result in the discovery of paleontological resources, the Project proponent's contractors shall cease all earth removal or disturbance activities in the vicinity and immediately notify the City selected paleontologist who shall immediately notify the Director of Development Services. The City selected paleontologist shall evaluate all potential paleontological findings in accordance with the Paleontological Resource Monitoring and Mitigation Program Monitoring, standard practice, the requirements of the City of Seal • Beach Cultural Resources Element, and other applicable regulations. Upon completion of the fieldwork, the City selected paleontologist shall prepare a Final Monitoring and Mitigation Report to be filed with the City and the repository to include, but not be limited to, a discussion of the results of the mitigation and monitoring program, an evaluation and analysis of the fossils collected (including an assessment of their significance, age, geologic context), an itemized inventory of fossils collected, a confidential appendix of locality and specimen data with locality maps and photographs, and an appendix of curation agreements and other appropriate communications. CUL-3 Should any human bone be encountered during any earth removal or disturbance activities, all activity shall cease immediately and the City selected archaeologist and Native American monitor shall be immediately contacted, who shall then immediately notify the Director of Development Services. The Director of Development Services shall contact the Coroner pursuant to Sections 5097.98 and 5097.99 of the Public Resources Code relative to Native American remains. Should the Coroner determine the human remains to be Native American, the Native American Heritage Commission shall be contacted pursuant to Public Resources Code Section 5097.98. CUL-4 If more than one Native American burial is encountered during any earth removal or disturbance activities, a "Mitigation Plan" shall be prepared and subject to approval by the City of Seal Beach Development Services Department. The Mitigation Plan shall include the following procedures: Page 23 Resolution Number 6273 Continued Native American Monitoring • All ground disturbance in any portions of the project area with the potential to contain human remains or other cultural material shall be monitored by a Native American representative of the Most Likely Descendant (MLD). Activities to be monitored shall include rough grading and grading of previously undisturbed deposit, with the exception of contexts that are clearly within undisturbed soil profiles. • Exposure and removal of each burial shall be monitored by a Native American. Where burials are clustered and immediately adjacent, one monitor is sufficient for excavation of two adjoining burials. • Excavation of test units shall be monitored. Simultaneous excavation of two test units if less than 20 feet apart may be monitored by a single Native American. • If screening of soil associated with burials or test units is done concurrently with and adjacent to the burial or test unit, the Native American responsible for that burial or test unit will also monitor the screening. If the screening is done at another location, a separate monitor shall be required. • All mechanical excavation conducted in deposits that may contain human remains(i.e., all areas not completely within undisturbed soil profiles) shall be monitored by a Native American. Notification Procedures for New Discoveries • When possible burials are identified during monitoring of mechanical excavation, or excavation of test units,the excavation shall be temporarily halted while the find is assessed in consultation with the lead field archaeologist. If the find is made during mechanical excavation, the archaeologist or Native American monitoring the activity shall have the authority to direct the equipment operator to stop while the find is assessed. If it is determined that the find does not constitute a burial, the mechanical excavation shall continue. • If the find is determined to be a human burial, the lead archaeologist shall immediately notify the Site Supervisor for the developer, as well as the Principal Investigator. The Principal Investigator shall immediately notify the MLD and the Director of Development Services for the City of Seal Beach. Page 24 Identification of Additional Burials • For all discovered human burials, attempts shall continue to be made to locate additional burials nearby through hand excavation techniques. This shall be done through the excavation of 1 x 1 meter exploratory test units (ETUs) placed along transects extending radially from each identified burial or burial cluster. The spacing of the ETUs shall be determined upon consultation with the Project Archaeologist and the MLD. The radial transects shall be designed to test areas within 50 feet (15 meters) from the edge of each burial or burial cluster. Excavation of these units shall be limited to areas containing intact cultural deposit (i.e., areas that have not been graded to the underlying undisturbed soil profiles) and shall be excavated until the undisturbed soil profiles are encountered, or to the excavation depth required for the approved grading plan. The soil from the ETUs along the radial transects shall be screened only if human remains are found in that unit. • Controlled grading shall be conducted within these 50-foot heightened investigation areas with a wheeled motor grader. The motor grader shall use an angled blade that excavates 1 to 2 inches at a pass, pushing the soil to the side to form a low windrow. Monitors shall follow about 20 feet behind the motor grader, examining the ground or evidence of burials. • When a burial is identified during controlled grading, the soil in windrows that may contain fragments of bone from that burial shall be screened. At a minimum this shall include the soil in the windrow within 50 feet of the burial in the direction of the grading. • If additional burials are found during controlled grading, additional ETUs will be hand excavated in the radial patterns described above. Burial Removal and Storage • Consultation with the MLD shall occur regarding the treatment of discovered human burials. If the MLD determines it is appropriate to have discovered human remains pedestaled for removal, that activity shall be conducted in a method agreed to by the MLD. • After pedestaling or other agreed upon burial • removal program is completed, the top of a burial shall be covered with paper towels to act as a cushion, and then a heavy ply plastic will be placed over the top to retain surface moisture. Duct tape shall be wrapped around the entire pedestal, securing the plastic bag • and supporting the pedestal. Labels shall be Page 25 Resolution Number 6273 placed on the plastic indicating the burial number and the direction of true north in relation to the individual burial. Sections of rebar shall be hammered across the bottom of the pedestal and parallel to the ground. When a number of parallel rebar sections have been placed this way, they shall be lifted simultaneously, cracking the pedestal loose from the ground. The pedestal shall then be pushed onto a thick plywood board and lifted onto a pallet.A forklift shall carry the pallet to a secure storage area or secure storage containers located on the subject property. • If another agreed upon burial removal program is utilized, that method shall be carried out in a manner agreed upon after consultation with the MLD and concurrence by the Director of Development Services. Study of Burial Remains • If the burials are removed in pedestal and are incompletely exposed, osteological studies are necessarily limited to determination (if possible) of age, sex, position, orientation, and trauma or pathology. After consultation, and only upon written agreement by the MLD, additional studies that are destructive to the remains may be undertaken, including radiocarbon dating of bone or DNA studies. If the MLD determines that only non-destructive additional studies may be allowed, one shell may be removed from each burial and submitted for radiocarbon dating. The assumption here is that the shell would have been part of the fill for the burial pit, and therefore would provide a maximum age for the burial. • The MLD may indicate a willingness to consider some additional exposure and study of the skeletal material removed from the sites. Such study would not involve removal of the remains from the project area, but rather would be undertaken near the storage area. To the extent allowed by the MLD, the bones would be further exposed within the existing pedestals or other medium containing the human remains and additional measurements taken. Consultation with the MLD regarding the feasibility of these additional studies prior to reburial would occur. Repatriation of Burials and Associated Artifacts • Once all portions of the project area have been graded to the underlying culturally sterile marine terrace deposits, or to the excavation depth required for the approved grading plan, the repatriation process shall be initiated for all recovered human remains and associated artifacts. Once a reburial site has been Page 26 identified and prepared, the remains and associated artifacts shall be transported from the secure storage area to the site for reburial. Appropriate ceremony will be undertaken during this process at the discretion of the MLD. Additional Studies Considerable additional data relating to regional research issues may be uncovered if substantial numbers of human burials and other archaeological features are encountered during the construction monitoring for the development. If this occurs, additional analysis shall be conducted. The analysis shall be designed to more completely address the research issues discussed in the approved'Research Design," and to provide additional mitigation of impacts to the sites in light of the new finds. The following studies would be potentially applicable: Radiocarbon Dating. In considering the implications of the burials in interpreting site use and regional settlement, it is critical to assess the time range represented by the interments. Do they correspond to the full temporal range of site use, or only a limited timeframe?Although direct dating of the bones may not be possible due to the destructive nature of the radiocarbon technique, the MLD may approve the removal of a single shell from the interior of each burial for dating. Although this shall not provide a direct date of the burial, assuming the shell was part of the burial fill it should provide a maximum age (that is, the burial should not be older than the shell). In addition, an equivalent number of additional samples from non-burial contexts would also be taken for comparative purposes.These data would provide a more secure measure of the intensity of occupation during different periods. G Animal Interments. Animal interments may be discovered within the project area. Because these are not human remains, somewhat more intensive study is possible. Because these features are uncommon and represent very culture-specific religious practices, they are useful in reconstructing cultural areas during certain times in prehistory. Analysis of animal interments will include: (1) exposure to determine burial position; (2) photo documentation; (3) examination of skeleton for age/sex; traumatic injury, pathology, butchering, or other cultural modification; (4) radiocarbon dating; and (5) examination of grave dirt for evidence of grave goods or stomach contents. Curation Cultural materials recovered from the cultural resources monitoring and mitigation program for the Page 27 Resolution Number 6273 development shall be curated either at an appropriate facility in Orange County, or, in consultation with the City, at the San Diego Archaeological Center. Preparation of Final Report The final technical report shall be prepared and submitted to the City within 12 months of the completion of the archeological field work. The report shall conform to the guidelines developed by the California Office of Historic Preservation for Archaeological Resource Management Reports (ARMR). It will be prepared in sufficient quantity to distribute to interested regional researchers and Native American groups. It shall thoroughly document and synthesize all of the findings from all phases of the cultural resources program. Funding shall be provided by the landowner. b. Facts in Support of Findings Due to the location of the cumulative projects and the high sensitivity for cultural resources to occur within the cities of Seal Beach and Long Beach, there is the potential that unknown archeological resources, including burial sites, and paleontological resources could occur at one or more of the cumulative project sites. The potential destruction of unknown archaeological resources associated with ground disturbance activities at the Project site and cumulative project sites could be cumulatively considerable, due to the collective loss of historical artifacts and knowledge regarding the culture of the people who lived at the respective sites. Additionally, the destruction of paleontological resources could be cumulatively considerable, as fossils provide biological information of ancient life, which would no longer be available for study. However, individual projects would be evaluated on a project by project basis to determine the extent of potential impacts to archeological and paleontological resources. Adherence to State and Federal statutes, as well as Project-specific mitigation measures, cumulative impacts to archaeological and paleontological resources would be reduced to less than significant levels. With implementation of Mitigation Measures CUL-1, CUL-2, CUL-3, and CUL-4, the Project would not cumulatively contribute to substantial impacts related to archaeological resources, burial sites, and paleontological resources. As such, a less than significant impact would occur in this regard. D. TRAFFIC AND CIRCULATION 1. Construction Traffic—Project Specific and Cumulative Impact Project construction has the potential to cause a significant increase in traffic for existing conditions when compared to the traffic capacity of the street system. This Project specific impact also has the potential to be cumulative considerable when coupled with cumulative projects in the area. Nevertheless, mitigation is imposed on the Project to ensure that any project specific and cumulative impact is less than significant. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative construction traffic impact. Specifically, the following mitigation measure is imposed upon the Project to ensure a less than significant impact: • TRA-1 Prior to Issuance of any grading and/or demolition permits, whichever occurs first, a Page 28 Construction Management Plan shall be submitted for review and approval by the Director of Development Services. The Construction Management Plan shall, at a minimum, address the following: • Traffic control for any street closure, detour, or other disruption to traffic circulation. • Identify the routes that construction vehicles will utilize for the delivery of construction materials (i.e., lumber, tiles, piping, windows, etc.), to access the site, traffic controls and detours, and proposed construction phasing plan for the project. • Specify the hours during which transport activities can occur and methods to mitigate construction-related impacts to adjacent streets. • Require the Applicant to keep all haul routes clean and free of debris, including but not limited to gravel and dirt as a result of its operations. The Applicant shall clean adjacent streets, as directed by the City Engineer (or representative of the City Engineer), of any material which may have been spilled, tracked, or blown onto adjacent streets or areas. • Hauling or transport of oversize loads shall be allowed between the hours of 9:00 AM and 3:00 PM only, Monday through Friday, unless approved otherwise by the City Engineer. No hauling or transport will be allowed during nighttime hours, weekends, or Federal holidays. • Use of local streets shall be prohibited. • Haul trucks entering or exiting public streets shall at all times yield to public traffic. • If hauling operations cause any damage to existing pavement, streets, curbs, and/or gutters along the haul route, the applicant shall be fully responsible for repairs. The repairs shall be completed to the satisfaction of the City Engineer. • All constructed-related parking and staging of vehicles shall be kept out of the adjacent public roadways and shall occur on-site or in public parking lots. • This Plan shall meet standards established in the current California Manual on Uniform Traffic Control Device(MUTCD) as well as City of Seal Beach requirements. b. Facts in Support of Findings As indicated in Table 5.5-12 in the EIR, site preparation is expected to generate 10 daily trips with 5 trips (5 inbound and 0 outbound) produced during Page 29 Resolution Number 6273 the AM peak hour and 5 trips (0 inbound and 5 outbound) produced during the PM peak hour. Site grading is expected to generate 308 daily trips with 42 trips (26 inbound and 16 outbound) produced during the AM peak hour and 42 trips (16 inbound and 26 outbound) produced during the PM peak hour. Construction related trips associated with trucks and employees traveling to and from the Project site may result in minor traffic delays within the project area. However, the potential traffic interference caused by construction vehicles would only be a temporary, short-term impact to vehicles using Marina Drive and 1st Street in the morning and afternoon hours. Further, the number of construction workers would vary depending on the specific construction activities over time. In order to reduce the impact of construction-related traffic, implementation of a construction management plan would be required in order to implement a variety of measures to minimize traffic and parking impacts upon the local circulation system (Mitigation Measure TRA-1). The construction management plan would include: prohibiting construction worker parking along local streets, identifying appropriate haul routes to avoid traffic disruptions, and limiting hauling activities to off-peak hours. Implementation of a construction management plan would ensure potential impacts associated with construction related traffic would be reduced to a less than significant level. With regard to cumulative impacts, the Marina Park Development would be the most likely project that would cumulatively contribute to construction traffic impacts in the area due to the proximity to the Project site. The Marina Park Development is anticipated to begin construction in 2014 at the earliest. The proposed Project anticipates that 24 homes would be constructed in 2014. Therefore, construction activities would likely overlap by one year in a worst case scenario. Construction activities within the overlapping year could result in traffic impacts to local roadways. However, the Project would be required to prepare a construction management plan in order to reduce the impact of construction- related traffic upon the local circulation system within the Project area. The Marina Park Development would also be required to reduce construction traffic impacts on the local circulation system and implement any required mitigation measures that may be prescribed pursuant to CEQA provisions. Therefore, the Project's contribution to cumulative construction traffic impacts would be less than significant with the implementation of Project specific Mitigation Measure TRA-1. In short, both the Project specific and cumulative construction traffic impact will be reduced to a level of insignificance with the implementation of a construction management.plan as required by Mitigation Measure TRA-1. 2. Hazardous Traffic Conditions — Project Specific and Cumulative Impact Project implementation has the potential to cause significant hazardous traffic conditions either on-site or in the surrounding area. Additionally, the • Project, coupled with other cumulative projects has the potential to create a cumulatively considerable hazardous traffic impact. With the implementation of various mitigation measures, any potential impact will be eliminated and will be less than significant. a. Findings • Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative hazardous traffic condition impact. Specifically, the following mitigation measures are imposed upon the Project to ensure a less than significant impact: Page 30 TRA-2 Prior to issuance of any grading permits, a Landscape Plan shall be submitted to the City Engineer verifying that all landscaping and/or hardscapes shall be designed such that a driver's clear line of sight is not obstructed and does not threaten vehicular or pedestrian safety consistent with Figure 10-1a, Site Distance Analysis Project Access Points at Marina Drive, and Figure 10-2a, Site Distance Analysis Project Access Points at First Street, of the Supplemental Traffic Assessment Ocean Place Residential Project — Alternative Plan (Traffic Impact Analysis), prepared by Linscott, Law& Greenspan Engineers (June 14, 2012). The Traffic Impact Analysis is incorporated by reference into this mitigation measure. TRA-3 Prior to the issuance of any building permits, a "STOP" sign and stop bar shall be installed at the project driveway ('A' Street) and alley (Alley `E') on Marina Drive and at the project driveway ('B' Street) and alley (Alley 'D') on 1st Street. Appropriate striping, signage, and/or pavement legends shall also be installed in accordance with Seal Beach standards. These improvements shall be indicated on the grading plan and Final Tentative Tract Map and shall be submitted to the City Engineer for review and approval. TRA-4 South of Marina Drive, the project applicant shall restripe 1st Street within the proposed 40-foot paved cross section to provide one 16-foot southbound departure lane, a 10-foot northbound left- turn lane, and a 14-foot northbound shared through/right-turn lane. South of Marina Drive, the project applicant shall modify the existing median and roadway cross section to minimize the offset through the intersection and realign the southbound approach with the proposed northbound approach on 1st Street. Within a recommended paved cross section of 40- feet, the project applicant shall provide one 16-foot northbound departure lane, a 10-foot southbound left- turn lane, and a 14-foot southbound through lane; a separate southbound right-turn lane. shall be maintained. These improvements shall be installed prior to the issuance of any building permits, and shall also be indicated on the grading plan and Final Tentative Tract Map and shall be submitted to the City Engineer for review and approval. b. Facts in Support of Findings Hazardous traffic conditions may be created by the Project with regard to sight distance for drivers at the proposed driveways and alleys, and access and egress to the Project site. Additionally, the Project, along with the Marina Park Development project has the potential to cause a similar cumulative level impact. As further detailed below, with the implementation of mitigation, any project specific hazardous traffic condition impact, and any cumulative impact, would be reduced to a less than significant level. With regard to sight distances, at intersections, a substantially clear line of sight should be maintained between the driver of a vehicle waiting at the crossroad and the driver of an approaching vehicle. Adequate time must be provided for the waiting vehicle to either cross all lanes of through traffic, cross Page 31 Resolution Number 6273 the near lanes and turn left, or turn right, without requiring through traffic to radically alter their speed. A sight distance evaluation was performed at the proposed Project driveways/alleys to determine if adequate sight distance would be provided, including an analysis of the revised tract map included with the Applicant's proposed refinements to the Project as discussed in Section III of these findings. As more fully described in the Draft EIR and the Supplemental Traffic Assessment Ocean Place Residential Project —Alternative Plan (Traffic Impact Analysis), prepared by Linscoft, Law& Greenspan Engineers (June 14, 2012), a motorist's sight distance may be obstructed by future project landscapes and/or hardscapes along the Project frontage. Figure 10-la and Figure 10-2a of the June 14, 2012 report, which report is hereby incorporated by this reference, indicate that sight distances at the Project driveways and alleys in the second revised tract map are expected to be adequate if obstructions within the sight triangles are minimized. Any landscaping and/or hardscapes would be required to be designed such that a driver's clear line of sight is not obstructed and does not threaten vehicular or pedestrian safety, as determined by the City Engineer (Mitigation Measure TRA-2). With implementation of Mitigation Measure TRA-2, potential sight distance impacts associated with the proposed Project would be reduced to a less than significant level. With regard to adequate access and egress, stop signs and stop bars would be required at the Project driveways and alleys, including appropriate striping, signage, and/or pavement legends in accordance with Seal Beach standards. These items would be implemented through the imposition of Mitigation Measure TRA-3, which has been revised from the Draft EIR to refer to the street names indicated on the second revised tract map. In conjunction with the proposed vacation of 1st Street, south of Manna Drive, 1st Street would be required to be restriped within the proposed 40-foot paved cross section to provide one 16-foot southbound departure lane, a 10-foot northbound left-turn lane, and a 14-foot northbound shared through/right-turn lane. In order to accommodate the proposed Project improvements on 15t Street, south of Marina Drive, the existing median and roadway cross section would be required to be modified to minimize the offset through the intersection and realign the southbound approach with the proposed northbound approach on 1st Street. Within a recommended paved cross section of 40-feet, the proposed Project would be required to provide one 16-foot northbound departure lane, a 10-foot southbound left-turn lane, and a 14-foot southbound through lane; a separate southbound right-turn lane would also be required to be maintained. Implementation of Mitigation Measure TRA-4 would ensure these improvements are put in place. Overall, with implementation of recommended mitigation, the proposed Project would not result in a hazardous condition either on-site or in the surrounding area,and impacts would be less than significant. With regard to cumulative impacts, the Marina Park Development is located to the northeast of the Project site and proposes an approximate 3.0-acre expansion of the existing park. The concept level site plan for the Marina Park Development anticipates conversion of two northbound lanes on 1St Street. The proposed Project would vacate a portion of 1st Street at the intersection of Marina Drive, which would be realigned as part of the proposed Project. It is anticipated that proposed intersection/roadway modifications associated with the proposed Project and Marina Park would be coordinated to ensure cumulative hazardous conditions would not occur. Mitigation is imposed on the Project to ensure both safe ingress and egress, and to ensure adequate sight distances exist. With mitigation, project impacts would not be cumulatively considerable and would be less than significant. Page 32 E. AIR QUALITY 1. Construction Emissions—Protects Level and Cumulative Short-term construction activities associated with the proposed Project could result in air pollutant emission impacts or expose sensitive receptors to substantial pollutant concentrations. Additionally, the Project could contribute to • a cumulatively considerable construction air emissions impact. However, with the implementation of mitigation, any potential impacts will be reduced to a less than significant level. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative construction air emissions impact. Specifically, the following mitigation measures are imposed upon the Project to ensure a less than significant impact: AQ-1 Prior to issuance of any Grading Permit, the Director of Public Works and the Building Official shall confirm that the Grading Plan, Building Plans, and • specifications stipulate that, in compliance with SCAQMD Rule 403, excessive fugitive dust emissions shall be controlled by regular watering or other dust prevention measures, as specified in the SCAQMD's Rules and Regulations. In addition, SCAQMD Rule 402 requires implementation of dust suppression techniques to prevent fugitive dust from creating a nuisance off-site. Implementation of the following measures would reduce short-term fugitive dust impacts on nearby sensitive receptors: • All active portions of the construction site shall be watered at least twice daily to prevent excessive amounts of dust; • On-site vehicle speed shall be limited to 15 miles per hour; • All on-site roads shall be paved where feasible, watered as needed (to maintain a moisture content of 12 percent), or chemically stabilized; • Visible dust beyond the property line which emanates from the project shall be prevented to the maximum extent feasible; • All material transported off-site shall be either sufficiently watered or securely covered to prevent excessive amounts of dust prior to . departing the job site; • Track-out devices shall be used at all construction site access points; • All delivery truck tires shall be watered down and/or scraped down prior to departing the job site; • Replace ground cover on disturbed areas quickly; and Page 33 Resolution Number 6273 Y Implement street sweeping program with Rule 1186-compliant PM10 efficient vacuum units. AQ-2 All trucks that are to haul excavated or graded material on-site shall comply with State Vehicle Code Section 23114 (Spilling Loads on Highways), with special attention to Sections 23114(b)(F) and (e)(4) as amended, regarding the prevention of such material spilling onto public streets and roads. Prior to the issuance of grading permits, the Applicant shall coordinate with the appropriate City of Seal Beach Engineer on hauling activities compliance. b. Facts in Support of Findings Short-term air quality impacts are predicted to occur during grading and construction operations associated with implementation of the proposed Project. Temporary air emissions would result from particulate (fugitive dust) emissions from grading and building construction; and exhaust emissions from the construction equipment and the motor vehicles of the construction crew. Fugitive dust emissions are not anticipated to cause any potential significant impacts as more fully detailed in the EIR. •Further, ROG emissions associated with asphalt and surface coatings would also not pose any potential significant impact. Lastly, construction equipment and worker vehicle exhaust likewise would not pose a potentially significant impact. However, PM10 and PM2.5, although not exceeding the South Coast Air Quality Management District's (SCAQMD)thresholds, will require the imposition of mitigation as the air basin is in nonattainment status for those two criteria pollutants. With the implementation of Mitigation Measures AQ-1 and AQ-2, that require compliance with SCAQMD's Rule 403 and compliance with State Vehicle Code Section 23114, the already less than significant PM10 and PM2.5 impact would be even further reduced. With regard to cumulative impacts, the SCAQMD neither recommends quantified analyses of cumulative construction emissions, nor does it provide separate methodologies or thresholds of significance to be used to assess cumulative construction impacts. As the Project Applicant has no control over the timing or sequencing of the related projects, any quantitative analysis to ascertain the daily construction emissions that assumes multiple, concurrent construction would be speculative. However, the Marina Park Development would be the project that would cumulatively contribute most to short-term air quality impacts in the area due to the proximity to the Project site. The Marina Park Development is anticipated to begin construction in 2014 at the earliest. The proposed Project, as analyzed in the Final EIR, anticipates that 24 homes would be constructed and painted in 2014.Therefore, construction activities would likely overlap by one year in a worst case scenario. The year of overlap would be the . proposed Project's final and lowest year of construction emissions. Construction- related criteria pollutant emissions are temporary in nature and cease following Project completion. Project compliance with SCAQMD rules and regulations and Mitigation Measures AQ-1 and AQ-2 would reduce construction-related impacts to less than significant levels. Per SCAQMD rules and mandates, as well as the CEQA requirement that significant impacts be mitigated to the extent feasible, these same requirements would also be imposed on construction projects throughout the Basin, which would include each of the related projects. Thus, it can be reasonably inferred that the Project-related construction activities, in combination with those from other cumulative projects in the area, would not deteriorate the local air quality and would not result in cumulative construction- related impacts. 2. Consistency with Regional Plans — Project Specific and Cumulative Development associated with the proposed Project would not be inconsistent with the 2007 SCAQMD Air Quality Management Plan (AQMP). Page 34 However, as articulated in the section above regarding construction air emissions, AQ-1 and AQ-2 are imposed upon the project as the air basin is in nonattainment for PM10 and PM2.5. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen the already less than significant impact associated with consistency with the 2007 AQMP. Specifically, the following mitigation measures are imposed upon the Project: AQ-1 Prior to issuance of any Grading Permit, the Director of Public Works and the Building Official shall confirm that the Grading Plan, Building Plans, and specifications stipulate that, in compliance with SCAQMD Rule 403, excessive fugitive dust emissions shall be controlled by regular watering or other dust prevention measures, as specified in the SCAQMD's Rules and Regulations. In addition, SCAQMD Rule 402 requires implementation of dust suppression techniques to prevent fugitive dust from creating a nuisance off-site. Implementation of the following measures would reduce short-term fugitive dust impacts on nearby sensitive receptors: • All active portions of the construction site shall be watered at least twice daily to prevent excessive amounts of dust; • On-site vehicle speed shall be limited to 15 miles per hour; • All on-site roads shall be paved where feasible, watered as needed (to maintain a moisture content of 12 percent), or chemically stabilized; • Visible dust beyond the property line which emanates from the project shall be prevented to the maximum extent feasible; • All material transported off-site shall be either sufficiently watered or securely covered to prevent excessive amounts of dust prior to departing the job site; • Track-out devices shall be used at all construction site access points; • All delivery truck tires shall be watered down and/or scraped down prior to departing the job site; • Replace ground cover on disturbed areas quickly; and • Implement street sweeping program with Rule 1186-compliant PM10 efficient vacuum units. AQ-2 All trucks that are to haul excavated or graded material on-site shall comply with State Vehicle Code Section 23114 (Spilling Loads on Highways), with special attention to Sections 23114(b)(F) and (e)(4) as amended, regarding the prevention of such Page 35 Resolution Number 6273 material spilling onto public streets and roads. Prior to the issuance of grading permits, the Applicant shall coordinate with the appropriate City of Seal Beach Engineer on hauling activities compliance. b. Facts in Support of Findings As more fully described in the EIR, the proposed Project would be consistent with the 2007 AQMP as it would satisfy the two key indicators of consistency identified by the SCAQMD's CEQA Handbook. The proposed Project would not contribute to the exceedance of an air pollutant concentration standard, as its localized impacts would be below significance thresholds. Additionally, the Project would not induce growth beyond what was assumed in the 2007 AQMP. Therefore, the Project would be consistent with the assumptions in the 2007 AQMP. As a result, the proposed Project would be consistent with the 2007 AQMP and impacts would be less than significant. Nevertheless, Mitigation Measures AQ-1 and AQ-2 are imposed upon the Project as the air basin is in nonattainment status for PM10 and PM2.5. F. NOISE 1. Construction Noise—Project Specific and Cumulative Grading and construction within the Project area could result in significant temporary noise impacts to nearby sensitive receptors. Additionally, the Project construction, coupled with other cumulative project construction, could contribute to a cumulative construction noise impact. With the implementation of mitigation, these impacts will be reduced to a level of insignificance. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative construction noise impact. Specifically, the following mitigation measure is imposed upon the Project to ensure a less than significant impact: N-1 Prior to Grading Permit issuance, the project shall demonstrate, to the satisfaction of the Seal Beach Development Services Department that the project complies with the following: • Construction contracts specify that all construction equipment, fixed or mobile, shall be equipped with properly operating and maintained mufflers and other,State required noise attenuation devices. • The Applicant shall provide, to the satisfaction of the City of Seal Beach Development Services Department, a qualified "Noise Disturbance Coordinator." The Disturbance Coordinator shall be responsible for responding to any local complaints about construction noise. When a complaint is received, the Disturbance Coordinator shall notify the City within 24-hours of the complaint and determine the cause of the noise complaint (e.g., starting too early, bad muffler, etc.) and shall implement reasonable measures to resolve the complaint, as deemed acceptable by the City Development Services Department. The contact name and the Page 36 telephone number for the Disturbance Coordinator shall be clearly posted on-site. Solid noise attenuation barriers (temporary barriers or noise curtains) with a sound transmission coefficient (STC) of at least 20 shall be used along the eastern project boundary (along 1st Street) during the construction grading phase only Noise attenuation barriers constructed at the property lines to a height of 10 feet with an STC rating of at least 20 are capable of reducing noise levels by 7.7 dBA. When feasible, construction haul routes shall be designed to avoid noise sensitive uses (e.g., residences, convalescent homes, etc.). During construction, stationary construction equipment shall be placed such that emitted noise is directed away from sensitive noise receivers. Construction activities shall not take place outside of the allowable hours specified by the City's Municipal Code Section 7.15.025 (7:00 a.m. and 8:00 p.m. on weekdays, 8:00 a.m. and 8:00 p.m. on Saturdays, and 9:00 a.m. and 8:00 p.m. on Sundays or holidays). b. Facts in Support of Findings. High groundborne noise levels and other miscellaneous noise levels can be created by the operation of heavy-duty trucks, backhoes, bulldozers, excavators, front-end loaders, scrapers, and other heavy duty construction equipment. The grading phase would include mostly site preparation activities with rough grading followed by fine grading. Construction equipment utilized during this phase would include graders, scrapers, excavators, bulldozers, and tractors. The paving phase would involve asphalt laydown activities which would utilize pavers, rollers, and other paving equipment. The building construction phase would utilize cranes, tractors, and forklifts. As more fully detailed in the EIR, construction noise associated with the proposed.Project would not expose surrounding sensitive receptors to noise levels in excess of the Speech Interference Criteria (65 dBA) during four of five stages of construction.The Speech Interference Criteria '(65 dBA) would be exceeded by approximately 1.9 dBA during the grading phase at residential uses to the east of the Project site. Municipal Code Section 7.15.025 Exemptions, exempts construction activities from the provisions of the Noise Ordinance provided that they take place between the hours of 7:00 a.m. and 8:00 p.m. on weekdays, between 8:00 a.m. and 8:00 p.m. on Saturdays, and between 9:00 a.m. and 8:00 p.m. on Sundays or holidays. The Project would be required to comply with these limitations, and construction activities would not take place outside of the exempted times. However, Mitigation Measure N-1 would require the use of solid construction noise barriers along the eastern boundary of the Project site during the grading phase only to ensure the Speech Interference Criteria(65 dBA)would not be exceeded. As some of the homes in the Project are likely to be constructed prior to other homes, there is a potential for construction noise impacts to those already residing in fully constructed homes. However, it is likely that the greatest noise impacts would occur during the initial grading, and not during building construction, thereby minimizing impacts on any individuals already residing in fully constructed homes. Implementation of Mitigation Measure N-1 would also Page 37 Resolution Number 6273 require mobile equipment to be muffled and placed such that emitted noise is directed away from these sensitive noise receptors. In short, implementation of Mitigation Measure N-1 would minimize any impacts from construction noise and would ensure that impacts are reduced to a less than significant level. With regard to cumulative impacts, the Marina Park Development would be the only project that would cumulatively contribute to short-term noise impacts in the area due to the proximity to the Project site and the type of development. The Marina Park Development is anticipated to begin construction in 2014 at the earliest. The proposed Project, as analyzed in the Final EIR, anticipates that 24 homes would be constructed and painted in 2014. Therefore, construction activities would likely overlap by one year in a worst case scenario. Construction activities within the overlapping year could result in excessive noise impacts to surrounding residential uses. However, as stated above, the proposed Project would comply with the City's Municipal Code's limitations on allowable hours of construction and would implement Mitigation Measure N-1 to reduce construction noise impacts to less than significant levels. The Marina Park Development construction activities would also be required to comply with the City's Municipal Code's limitations on allowable hours of construction and would also be exempt from the noise standards of the Municipal Code. Additionally, the Marina Park . Development project would be required to implement any other required mitigation measures that may be prescribed pursuant to CEQA provisions. Therefore, the Project's contribution to cumulative noise impacts would be less than significant. G. GEOLOGY AND SOILS 1. Liquefaction, Lateral Spreading, Landslides. Settlement and/or Ground Lurching -Project Specific and Cumulative The Project has the potential to expose people or structures to potential substantial adverse effects associated with seismically induced liquefaction, lateral spreading, landsliding, settlement, and/or ground lurching. Further, the Project has the potential to also cause a cumulative impact in this regard. With the implementation of various mitigation measures, any potential impact and cumulative impact will be reduced to a level of insignificance. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative impact Specifically, the following mitigation measures are imposed upon the Project to ensure a less than significant impact: GEO-1 Prior to issuance of any grading permit, the project applicant shall prepare a Final Soils/Geotechnical Engineering Report for review and approval by the City's Engineer. The Final Soils Geotechnical Engineering Report shall be prepared by a professional engineer and certified engineering geologist licensed by the State of California, in consultation with a corrosion engineer, and demonstrate compliance with the following recommendations identified in the Preliminary Geotechnical Evaluation for Proposed Residential Development, prepared by GeoTek, Inc., dated September 12, 2005, and the Geology, Soils, and Seismicity Report in Support of DWP Specific Plan Amendment EIR, Seal Beach California, prepared by D. Scott Magorien, C.E.G. Consulting Engineering Geologist, dated June 27, 2011, and any additional recommendations identified by the City's Engineer. The Preliminary Geotechnical Evaluation and Page 38 Geology Report are included in Appendix 11.8, Geology, Soils, and Seismicity Data of this EIR and are incorporated by reference into this mitigation measure. The following recommendations shall be addressed and incorporated into the Final Soils Geotechnical Engineering Report: Earthwork Considerations Earthwork and grading shall be performed in accordance with the applicable grading ordinances of the current California Building Code (CBC), and the following recommendations. The Grading Guidelines included in Appendix D of the Preliminary Geotechnical Evaluation for Proposed Residential Development, prepared by GeoTek, Inc., dated September 12, 2005 outline general procedures and do not anticipate all site-specific situations. In the event of conflict, the following recommendations shall supersede those contained in Appendix D of the Preliminary Geotechnical Evaluation for Proposed Residential Development. • Site Clearing. In areas of planned grading or improvements, the site shall be cleared of vegetation, roots, and debris, and properly disposed of offsite. Any holes resulting from site clearing, tree removal, and/or the backhoe trenches excavated shall be replaced with properly compacted fill materials. • Fills. Any import fill shall consist of relatively low-expansive soils (EI<50) and shall be evaluated by a Registered Civil Engineer/Geotechnical Engineer, approved by the City, prior to arrival at the project site. The fill materials shall be compacted in layers no thicker than 8 inches to at least 90 percent of maximum dry density with a moisture content of at least optimum, as determined in accordance with American Society for Testing and Materials (ASTM) Test Method D1557-00. Those areas to receive fill shall be scarified to a depth of 8 inches; moisture conditioned to at least optimum moisture content and recompacted to at least 90 percent of maximum dry density. • Removals. Existing fill materials shall be subject to complete removal and recompaction within the limits of grading. In those areas where the depth of existing fill materials extends below the groundwater table, the upper eight to 10 feet of soil, along with organic and other deleterious materials, shall be removed. If saturated and yielding subgrade conditions are encountered upon removal of the upper soils within those areas exhibiting a shallow ground water surface, the contractor shall place uniform sized,%- inch crushed rock within the area exhibiting the "pumping" conditions. The crushed rock shall be properly tracked into the underlying soils such that it is Page 39 Resolution Number 6273 adequately intruded into and interlocks with the soils. The necessary thickness of the crushed rock shall be evaluated during construction. Following the placement and tracking of the gravel layer into the underlying"pumping"soils, Mirafi 600X stabilization fabric (or approved equivalent) shall be placed upon the gravel layer. Fill soils shall then be placed upon the fabric and compacted to a minimum 90 percent relative compaction (based on ASTM test method D1557) until finished grades .are reached. The gravel and stabilization fabric shall extend at least 5 feet laterally beyond the limits of the"pumping"areas.These operations shall be performed under the observation and testing of a professional engineer or a certified engineering geologist licensed by the State of California, approved by the City in order to evaluate the effectiveness of these measures and to provide additional recommendations, as • warranted. Following the completion of rough grading at the site, settlement monuments shall be installed at finish rough grade. These monuments shall be established based on a known bench mark and their elevations shall be monitored by a licensed land surveyor on a weekly basis. The surveyor's settlement monument data shall be reviewed weekly by the Registered Civil Engineer/Geotechnical Engineer, approved by the City. This monitoring shall continue until the consolidation is deemed to have sufficiently stabilized. Once it has been concluded that the remaining settlement is within acceptable levels, the settlement monuments may be destroyed and fine grading may proceed. • Excavation Characteristics. All temporary excavations for grading purposes and installation of underground utilities shall be constructed in accordance with Occupational Safety and Health Administration (OSHA) guidelines. • Expansive Soils. Placement of any clayey soils within three feet of finish grade shall be avoided. Foundation Support • Conventional Foundation Recommendations. In the areas where complete removal and recompaction of the upper soils can be accomplished, the proposed residential structures shall be supported on conventional continuous or isolated spread footings bearing entirely upon properly compacted fill materials. Foundations supporting single story structures shall be constructed with an embedment of at least 12 inches below finish grade, while those supporting two story structures shall be constructed with an embedment of at least 18 Page 40 inches below finish grade. At these depths, footings shall be designed for an allowable soil bearing value of 2,000 pounds per square foot (psf). This value shall be increased by one- third for loads of short duration, such as wind and seismic forces. Continuous footings supporting single-story structures shall have a minimum width of 12 inches, while those supporting two-story structures shall have a minimum width of 15 inches. Based on geotechnical considerations, footings shall be provided with reinforcement consisting of two No. 4 rebars, one top and one bottom. A minimum width of 24 inches for isolated spread footings shall be provided. Passive resistance to lateral loads shall be computed as an equivalent fluid pressure having a density of 250 psf per foot of depth to a maximum earth pressure of 3,000 psf. A coefficient of friction between soil and concrete of 0.30 shall be used with dead load forces. When combining passive and frictional resistance, the passive pressure component shall be reduced by one- third. • Special Foundation Systems. In the areas where incomplete removals are performed and/or the potential for seismically induced differential settlement exists,special foundation systems such as mat foundations, post- tensioned slabs, or drilled pier foundation systems shall be considered for support of the proposed residential structures. If mat foundations are used to support the proposed residential structures,the mat foundations shall be designed to bridge over voids that may develop under the slab due to differential settlement. The mat foundation shall be founded within compacted fill materials, with a minimum embedment of 18 inches below finish grade. For mats founded on soft, wet, or cohesionless soils, special preparation of the bottom shall be required to support construction traffic. Mat foundations shall be properly reinforced to form a relatively rigid structural unit in accordance with the structural engineers design. For preliminary design purposes, an uncorrected modulus of subgrade reaction of 100 pounds per cubic inch (pci) shall be assumed. For large foundations, the modulus shall be reduced by 75 percent (i.e., to 25 pci). Actual geotechnical design parameters shall be provided upon completion of a more complete geotechnical evaluation of the proposed building site. If post-tensioned slabs are used to support the proposed residential structures, the structural design of post-tensioned slabs shall follow the recommendations of the Post-Tensioning Institute (PTI) Method and Section 1819 of the 2001 California Building Code (i.e., 1808 [Foundations] and 1808.6.2 [ Slab on Ground Page 41 Resolution Number 6273 Foundations]). Based on the geotechnical data acquired during the subsurface exploration, an allowable bearing capacity of 1,500 psf, and a slab-subgrade friction coefficient of 0.75 shall be used for design of post-tensioned slabs. Final design shall be verified based upon actual soil conditions encountered and results of laboratory testing performed during or at the completion of site grading. If drilled piers are used to support the proposed residential structures, the drilled piers shall be designed utilizing either end-bearing or skin friction design. Drilled piers shall be embedded at least 5 feet within the alluvial materials or 14 feet below the existing ground surface (whichever is deeper). Design of drilled piers subjected to earthquake loading shall consider the effects of downdrag, due to the potential for liquefaction within portions of the fill. Because of the relatively high ground water level, along with the presence of poorly graded sands within the fill and alluvium, temporary casing or bentonite slurry shall be utilized to support the walls of the shaft prior to the placement of concrete. Further, the cleaning of loose slough from the bottom of the shaft excavation shall be warranted for drilled piers that will derive their support from end-bearing conditions. • Seismic Design Parameters. Seismically resistant structural design in accordance with local building ordinances shall be followed during the design of all structures. For the purpose of seismic design, a Type B seismic source (L.A. Basin segment of the Newport- Inglewood Fault) located less than 2 kilometers from the site shall be used. • Foundation Setbacks. Where applicable, the following setbacks shall apply to all foundations: o The outside bottom edge of all footings shall be set back a minimum of HI3 (where H is the slope height) from the face of any descending slope. The setback shall be at least seven feet and need not exceed 20 feet. o The bottom of all footings for structures near retaining walls shall be deepened so as to extend below a 1:1 projection upward from the bottom inside edge of the wall stem. o The bottom of any existing foundations for structures shall be deepened so as to extend below a 1:1 projection upward from the bottom of the nearest excavation. Page 42 • Slab-On-Grade. Where applicable, concrete slabs (including the mat foundations recommended above) shall be a minimum of four inches thick and reinforced as per • structural engineer requirements. Control joints shall be provided to help reduce random cracking. Slabs shall be underlain by a four inch thick capillary break layer consisting of clean sand (S.E. of 30 or greater). Where moisture condensation is undesirable, all slabs shall be underlain with a minimum six mil polyvinyl chloride membrane, sandwiched between two layers of clean sand (S.E. 30 or greater), each being at least two inches thick. Care shall be taken to adequately seal all seams and not puncture or tear the membrane. The sand shall be proof rolled. This recommendation is based on soil support characteristics only. The structural engineer shall design the actual slab and beam reinforcement based on expansion indices of the finish grade soils, actual loading conditions, and possible concrete shrinkage. • Soil Corrosivity. A corrosion engineer shall be consulted to provide recommendations for proper protection of buried metal pipes at this site. • Utilities. Due to the project site's susceptibility to liquefaction and a considerable amount of seismically-induced settlement and lateral spreading, consideration shall be given to "flexible" design for on-site utility lines and connections. Except where extending perpendicular to/under proposed foundations, utility trenches shall be constructed outside a 1:1 projection from the base-of foundations. Trench excavations for utility lines which extend under structural areas shall be properly backfilled and compacted. Utilities shall be bedded and backfilled with clean sand or approved granular soil to a depth of at least one foot over the pipe. This backfill shall be uniformly watered and compacted to a firm condition for pipe support. The remainder of the backfill shall be typical on-site soil or imported soil which shall be placed in lifts not exceeding eight inches in thickness,watered or aerated to 0 to 3 percent above the optimum moisture content, and mechanically compacted to at least 90 percent of maximum dry density (based on ASTM D1557). Concrete Construction Concrete construction shall follow the California Building Code and American Concrete Institute guidelines regarding design, mix placement and curing of the concrete. Page 43 Resolution Number 6273 • Cement Type.Type 11 cement or an equivalent shall be used in those concrete elements that will be in contact with the upper soils. • Control Flatwork. Control joints shall be provided in accordance with American Concrete Institute Guidelines to control cracking of exterior concrete flatwork (patios, walkways, driveways, etc.). Other methods to control cracking shall include careful control of water/cement ratios in the concrete, along with taking appropriate curing precautions during the placement of concrete in hot or windy weather. Retaining Wall Design and Construction Recommendations presented herein apply to typical masonry or concrete vertical retaining walls to a maximum height of 10 feet. Additional review and recommendations shall be required for higher walls. Foundations for retaining walls embedded a minimum of 18 inches into compacted fill shall be designed using a net allowable bearing capacity of 2,000 psf. An increase of one-third shall be applied when considering short-term live loads (e.g., seismic and wind loads). The passive earth pressure shall be computed as an equivalent fluid having a density of 250 psf per foot of depth, to a maximum earth pressure of 3,000 psf. A coefficient of friction between soil and concrete of 0.30 shall be used with dead load forces. When combining passive pressure and frictional resistance, the passive pressure component shall be reduced by one-third. An equivalent fluid pressure approach shall be used to compute the horizontal active pressure against the wall. The appropriate fluid unit weights are provided below for specific slope gradients of retained materials. _. :Surface°Slope of - :, • . Equivalent , .• • ., Retained. . • - Fluid , - • Materials Pressure (H:V): . ., : (PCF) •.. Level 35 2:1 55 The above equivalent fluid weights do not include other superimposed loading conditions such as expansive soil, vehicular traffic, structures, seismic conditions or adverse geologic conditions. • Wall Backfill and Drainage. The onsite sandy materials possessing a low expansion potential that are used for backfill shall be screened of greater than three inch size gravels. If other materials are present the parameters provided shall be reviewed and if necessary, modification to the wall designs shall be made. The backfill materials shall be placed in lifts no greater than eight inches in thickness and compacted at 90 percent relative compaction in accordance with ASTM Test Method D1557- Page 44 00. Proper surface drainage shall be provided and maintained. Retaining walls shall be provided with an adequate pipe and gravel back drain system to prevent buildup of hydrostatic pressures. Backdrains shall consist of a 4-inch diameter perforated PVC pipe embedded in a minimum of one cubic foot per lineal foot of 3/8 to one inch clean crushed rock or equivalent, wrapped in filter fabric (Mirafi 140N or an approved equivalent). The drain system shall be connected to a suitable outlet. A minimum of two outlets shall be provided for each drain section. Walls from two to four feet in height shall be drained using localized gravel packs behind weep holes at 10 feet maximum spacing (e.g., approximately 1.5 cubic feet of gravel in a woven plastic bag). Weep holes shall be provided or the head joints omitted in the first course of block extended above the ground surface. Post Construction • Landscape Maintenance and Planting. Positive surface drainage away from graded slopes shall be maintained and only the amount of irrigation necessary to sustain plant life shall be provided for planted slopes. Plants selected for landscaping shall be lightweight, deep-rooted types that require little water and are capable of surviving the prevailing climate. Over watering shall be avoided. The soils shall be maintained in a solid to semisolid state as defined by the materials'Atterberg Limits. Care shall be taken when adding soil amendments to avoid excessive watering. Leaching as a method of soil preparation prior to planting shall not occur. Planting placed adjacent to structures in planter or lawn areas shall be avoided. If used, waterproofing of the foundation and/or subdrains shall occur. • Drainage. Positive site drainage shall be maintained at all times. Drainage shall not flow uncontrolled down any descending slope. Water shall be directed away from foundations and not allowed to pond or seep into the ground. Pad drainage shall be directed toward approved area(s). Positive drainage shall not be blocked by other improvements. A de- watering system shall be implemented if below- grade construction (i.e., basements, etc.) is planned to extend down to or below depths of between nine and 15 feet below existing site grades Implementation and operation (as deemed necessary) of de-watering procedures/equipment both during subterranean construction (if planned) and throughout the lifetime of the structure(s) shall occur. A contractor specializing in the design and implementation of de-watering systems Page 45 Resolution Number 6273 shall be consulted prior to the beginning of construction activities. Plan Review and Construction Observations Site grading, specifications, and foundation plans shall be reviewed by a Geotechnical Engineer, approved by the City, prior to construction to verify conformance with the above recommendations. It is recommended that a Geotechnical Engineer be present during site grading and foundation construction to check for proper implementation of the geotechnical recommendations. The Geotechnical Engineer shall perform at least the following duties: • Observe site clearing and grubbing operations for proper removal of all unsuitable materials. • Observe and test bottom of removals prior to fill placement. • Evaluate the suitability of onsite and import materials for fill placement, and collect soil samples for laboratory testing where necessary. • Observe the fill for uniformity during placement including utility trenches. Also, test the fill for field density and relative compaction. • Observe and probe foundation materials to confirm suitability of bearing materials and proper footing dimensions. GEO-2 Prior to issuance of any grading permit, the Grading Plan shall incorporate all engineering recommendations contained within the Final Soils/Geotechnical Engineering Report for the proposed project during project site design and construction, in order to reduce any potential soil and geotechnical hazards at the project site. These recommendations shall be stipulated in the construction contracts and specifications. GEO-3 Prior to issuance of any building permit for development of each residential lot, the building and engineering plans shall incorporate all engineering recommendations contained within the Final Soils/Geotechnical Engineering Report for the proposed project during lot site design and construction, in order to reduce any potential soil and geotechnical hazards at the residential lots. These recommendations shall be stipulated in the building and engineering plans and specifications. b. Facts in Support of Findings Liquefaction. Saturated paralic soils are subject to varying amounts of liquefaction-induced settlement resulting from strong seismically-induced ground motions. The impacts to structures having footings or structural. elements founded in these soils could be significant unless mitigated. Additionally, the susceptibility of paralic soils, as well as non-engineered (i.e., loose) fill soils to seismically-induced settlement presents a significant impact to the Project site. Page 46 Lateral Spreading. Due to the presence of underlying liquefaction-prone soils and the Project site's proximity to the San Gabriel River, there is high potential for seismically-induced lateral spreading to occur at the Project site. Significant distress to above- and below-ground structures would occur in the event of this form of seismically-induced landsliding. Lateral spreading could impact a majority(approximately 80 percent)of the proposed residential area, as well as the southern (approximately 25 percent) and western central portion of the Project site.The impact could be significant unless mitigated. Landslidinq. Given the perceived, weak nature of the soils underlying the levee of the San Gabriel River, the levee and portions of the Project site along the eastern side of the levee are subject to landsliding during a moderate to strong seismic event in the area. Further, ground lurching may occur where deposits of loose alluvium and/or artificial fill soils exist adjacent to the San Gabriel River levee.The impact could be significant unless mitigated. Settlement. Holocene-age paralic soils, as well as non-engineered (i.e., loose) fill soils located within the Project site, are subject to seismically-induced settlement.The impact could be significant unless mitigated. Ground Lurching. Ground lurching may occur where deposits of loose alluvium and/or artificial fill soils exist adjacent to the San Gabriel River. The impact could be significant unless mitigated. The City regulates geotechnical hazards associated with site development through its Municipal Code, including compliance with the California Building Code. Municipal Code Section 10.55.020, Soils Reports, requires a preliminary soils report concurrent with submittal of the subdivision's improvement plans, prepared by a registered civil engineer and based upon adequate test borings. The preliminary soils report is required to identify hazards and problems related to soils and include methods of eliminating or reducing the hazards or problems. The preliminary soils report is also required to include a field investigation and laboratory tests for grading and design recommendations, including corrective actions to prevent structural damages. In compliance with Municipal Code Section 10.55.020, the Preliminary Geotechnical Evaluation and Geology Report have been prepared to identify existing soils and geotechnical conditions that occur within the Project site, including preliminary recommendations pertaining to design and construction. The Preliminary Geotechnical Evaluation and Geology Report provide recommendations regarding earthwork, foundation support, concrete construction, retaining wall design and construction, and post construction guidelines, among other recommendations, that would be required to be incorporated into the design and construction phases of the proposed Project. According to Municipal Code Section 10.55.020, if the preliminary soils report indicates the presence of critically expansive soils or other soil problems that could potentially lead to structural defects if not corrected, the City Engineer or Building Official may require the subdivider to submit a subsequent soils investigation of each parcel in the subdivision prior to approval of Final Tract Map. Municipal Code Section 10.55.020 also requires submittal of a final soils report to ensure compliance with the recommendations of the preliminary soils report and specifications for the Project, and to provide information relative to soils conditions that may differ from those described in the preliminary soils reports, along with any corrections, additions, or modifications not shown on the approved plans. As concluded in the Preliminary Geotechnical Evaluation and Geology Report, soil conditions exist that could potentially lead to structural defects if not corrected. Therefore, as part of the Final Tract Map, a Final Soils/Geotechnical Engineering Report would be required to ensure compliance with the recommendations of the Preliminary Geotechnical Evaluation and Geology Report and any recommendations identified by the City's Engineer pursuant to Mitigation Measure GEO-1. In addition, the Final Grading Plan for the tentative tract map and building and engineering plans for the future residential developments would be required to incorporate all engineering recommendations within the Final Soils/Geotechnical Engineering Report as specified in Mitigation Measures GEO-2 and GEO-3. With implementation of Page 47 Resolution Number 6273 • Mitigation Measure GEO-1, GEO-2, and GEO-3, potential impacts associated with seismically induced hazards would be reduced to a less than significant level. With regard to cumulative impacts,with the incorporation of GEO-1, GEO- 2, and GEO-3, the Project would not contribute to cumulative impacts. Therefore,with mitigation, any cumulative impact would be less than significant. 2. Unstable Soils—Project Specific and Cumulative Development of the Project could be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the Project. In addition, the Project has the potential to contribute to a cumulative impact in this regard. However, mitigation is imposed to ensure a less than significant impact. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative impact. Specifically, the following mitigation measures are imposed upon the Project to ensure a less than significant impact: GEO-1 Prior to issuance of any grading permit, the project applicant shall prepare a Final Soils/Geotechnical Engineering Report for review and approval by the City's Engineer. The Final Soils Geotechnical Engineering Report shall be prepared by a professional engineer and certified engineering geologist licensed by the State of California, in consultation with a corrosion engineer, and demonstrate compliance with the following recommendations identified in the Preliminary Geotechnical Evaluation for Proposed Residential Development, prepared by GeoTek, Inc., dated September 12, 2005, and the Geology, Soils, and Seismicity Report in Support of DWP Specific Plan Amendment EIR, Seal Beach California, prepared by D. Scott Magorien, C.E.G. Consulting Engineering Geologist, dated June 27, 2011, and any additional recommendations identified by the City's Engineer. The Preliminary Geotechnical Evaluation and Geology Report are included in Appendix 11.8, Geology, Soils, and Seismicity Data of this EIR and are incorporated by reference into this mitigation measure. The following recommendations shall be addressed and incorporated into the Final Soils Geotechnical Engineering Report: Earthwork Considerations Earthwork and grading shall be performed in accordance with the applicable grading ordinances of the current California Building Code (CBC), and the following recommendations. The Grading Guidelines included in Appendix D of the Preliminary Geotechnical Evaluation for Proposed Residential Development, prepared by GeoTek, Inc., dated September 12, 2005 outline general procedures and do not anticipate all site-specific situations. In the event of conflict, the following recommendations shall supersede those contained in Appendix D of the Preliminary Geotechnical Evaluation for Proposed Residential Development. • Page 48 • Site Clearing. In areas of planned grading or improvements, the site shall be cleared of vegetation, roots, and debris, and properly disposed of offsite. Any holes resulting from site clearing, tree removal, and/or the backhoe trenches excavated shall be replaced with properly compacted fill materials. • Fills. Any import fill shall consist of relatively low-expansive soils (EI<50) and shall be evaluated by a Registered Civil Engineer/Geotechnical Engineer, approved by the City, prior to arrival at the project site. The fill materials shall be compacted in layers no thicker than 8 inches to at least 90 percent of maximum dry density with a moisture content of at least optimum, as determined in accordance with American Society for Testing and Materials (ASTM) Test Method D1557-00. Those areas to receive fill shall be scarified to a depth of 8 inches; moisture conditioned to at least optimum moisture content and recompacted to at least 90 percent of maximum dry density. • Removals. Existing fill materials shall be subject to complete removal and recompaction within the limits of grading. In those areas where the depth of existing fill materials extends below the groundwater table, the upper eight to 10 feet of soil, along with organic and other deleterious materials, shall be removed. If saturated and yielding subgrade conditions are encountered upon removal of the upper soils within those areas exhibiting a shallow ground water surface, the contractor shall place uniform sized, '/<-inch crushed rock within the area exhibiting the "pumping" conditions. The crushed rock shall be properly tracked into the underlying soils such that it is adequately intruded into and interlocks with the soils. The necessary thickness of the crushed rock shall be evaluated during construction. Following the placement and tracking of the gravel layer into the underlying "pumping"soils, Mirafi 600X stabilization fabric (or approved equivalent) shall be placed upon the gravel layer. Fill soils shall then be placed upon the fabric and compacted to a minimum 90 percent relative compaction (based on ASTM test method D1557) until finished grades are reached. The gravel and stabilization fabric shall extend at least 5 feet laterally beyond the limits of the"pumping"areas. These operations shall be performed under the observation and testing of a professional engineer or a certified engineering geologist licensed by the State of California, approved by the City in order to evaluate the effectiveness of these measures and to provide additional recommendations, as warranted. Following the completion of rough grading at the site, settlement monuments shall Page 49 Resolution Number 6273 be installed at finish rough grade. These monuments shall be established based on a known bench mark and their elevations shall be monitored by a licensed land surveyor on a weekly basis. The surveyor's settlement monument data shall be reviewed weekly by the Registered Civil Engineer/Geotechnical Engineer, approved by the City. This monitoring shall continue until the consolidation is deemed to have sufficiently stabilized. Once it has been concluded that the remaining settlement is within acceptable levels, the settlement monuments may be destroyed and fine grading may proceed. • Excavation Characteristics. All temporary excavations for grading purposes and installation of underground utilities shall be constructed in accordance with Occupational Safety and Health Administration (OSHA) guidelines. • Expansive Soils. Placement of any clayey soils within three feet of finish grade shall be avoided. Foundation Support • Conventional Foundation Recommendations. In the areas where complete removal and recompaction of the upper soils can be accomplished, the proposed residential structures shall be supported on conventional continuous or isolated spread footings bearing entirely upon properly compacted fill materials. Foundations supporting single story structures shall be constructed with an embedment of at least 12 inches below finish grade, while those supporting two story structures shall be constructed with an embedment of at least 18 inches below finish grade. At these depths, footings shall be designed for an allowable soil bearing value of 2,000 pounds per square foot (psf). This value shall be increased by one- third for loads of short duration, such as wind and seismic forces. Continuous footings supporting single-story structures shall have a minimum width of 12 inches, while those supporting two-story structures shall have a minimum width of 15 inches. Based on geotechnical considerations, footings shall be provided with reinforcement consisting of two No. 4 rebars, one top and one bottom. A minimum width of 24 inches for isolated spread footings shall be provided. Passive resistance to lateral loads shall be computed as an equivalent fluid pressure having a density of 250 psf per foot of depth to a maximum earth pressure of 3,000 psf. A coefficient of friction between soil and concrete of 0.30 shall be used with dead load forces. When combining passive and frictional resistance, the passive Page 50 pressure component shall be reduced by one- third. Special Foundation Systems. In the areas where incomplete removals are performed and/or the potential for seismically induced differential settlement exists, special foundation systems such as mat foundations, post- tensioned slabs, or drilled pier foundation systems shall be considered for support of the proposed residential structures. If mat foundations are used to support the proposed residential structures,the mat foundations shall be designed to bridge over voids that may develop under the slab due to differential settlement. The mat foundation shall be founded within compacted fill materials, with a minimum embedment of 18 inches below finish grade. For mats founded on soft, wet, or cohesionless soils, special preparation of the bottom shall be required to support construction traffic. Mat foundations shall be properly reinforced to form a relatively rigid structural unit in accordance with the structural engineers design. For preliminary design purposes, an uncorrected modulus of subgrade reaction of 100 pounds per cubic inch (pci) shall be assumed. For large foundations, the modulus shall be reduced by 75 percent (i.e., to 25 pci). Actual geotechnical design parameters shall be provided upon completion of a more complete geotechnical evaluation of the proposed building site. If post-tensioned slabs are used to support the proposed residential structures, the structural design of post-tensioned slabs shall follow the recommendations of the Post-Tensioning Institute (PTI) Method and Section 1819 of the 2001 California Building Code (i.e., 1808 [Foundations] and 1808.6.2 [ Slab on Ground Foundations]). Based on the geotechnical data acquired during the subsurface exploration, an allowable bearing capacity of 1,500 psf, and a slab-subgrade friction coefficient of 0.75 shall be used for design of post-tensioned slabs. Final design shall be verified based upon actual soil conditions encountered and results of laboratory testing performed during or at the completion of site grading. If drilled piers are used to support the proposed residential structures, the drilled piers shall be designed utilizing either end-bearing or skin friction design. Drilled piers shall be embedded at least 5 feet within the alluvial materials or 14 feet below the existing ground surface (whichever is deeper). Design of drilled piers subjected to earthquake loading shall consider the effects of downdrag, due to the potential for liquefaction within portions of the fill. Because of the relatively high ground water level, along with the presence of poorly graded sands within the fill and alluvium, temporary casing or Page 51 Resolution Number 6273 bentonite slurry shall be utilized to support the walls of the shaft prior to the placement of concrete. Further, the cleaning of loose slough from the bottom of the shaft excavation shall be warranted for drilled piers that will derive their support from end-bearing conditions. • Seismic Design Parameters. Seismically resistant structural design in accordance with local building ordinances shall be followed during the design of all structures. For the purpose of seismic design, a Type B seismic source (L.A. Basin segment of the Newport- Inglewood Fault) located less than 2 kilometers from the site shall be used. • Foundation Setbacks. Where applicable, the following setbacks shall apply to all foundations: o The outside bottom edge of all footings shall be set back a minimum of Hl3 (where H is the slope height) from the face of any descending slope. The setback shall be at least seven feet and need not exceed 20 feet. o The bottom of all footings for structures near retaining walls shall be deepened so as to extend below a 1:1 projection upward from the bottom inside edge of the wall stem. o The bottom of any existing foundations for structures shall be deepened so as to extend below a 1:1 projection upward from the bottom of the nearest excavation. • Slab-On-Grade. Where applicable, concrete slabs (including the mat foundations recommended above) shall be a minimum of four inches thick and reinforced as per structural engineer requirements. Control joints shall be provided to help reduce random cracking. Slabs shall be underlain by a four inch thick capillary break layer consisting of clean sand (S.E. of 30 or greater). Where moisture condensation is undesirable, all slabs shall be underlain with a minimum six mil polyvinyl chloride membrane, sandwiched between two layers of clean sand (S.E. 30 or greater), each being at least two inches thick. Care shall be taken to adequately seal all seams and not puncture or tear the membrane. The sand shall be proof rolled. This recommendation is based on soil support characteristics only. The structural engineer shall design the actual slab and beam reinforcement based on expansion indices of the finish grade soils, actual loading conditions, and possible concrete shrinkage. Page 52 • Soil Corrosivity. A corrosion engineer shall be consulted to provide recommendations for proper protection of buried metal pipes at this site. • Utilities. Due to the project site's susceptibility to liquefaction and a considerable amount of seismically-induced settlement and lateral spreading, consideration shall be given to "flexible" design for on-site utility lines and connections. Except where extending perpendicular to/under proposed foundations, utility trenches shall be constructed outside a • 1:1 projection from the base-of foundations. Trench excavations for utility lines which extend under structural areas shall be properly backfilled and compacted. Utilities shall be bedded and backfilled with clean sand or approved granular soil to a depth of at least one foot over the pipe. This backfill•shall be uniformly watered and compacted to a firm condition for pipe support. The remainder of the backfill shall be typical on-site soil or imported soil which shall be placed in lifts not exceeding eight inches in thickness,watered or aerated to 0 to 3 percent above the optimum moisture content, and mechanically compacted to at least 90 percent of maximum dry density (based on ASTM D1557). Concrete Construction Concrete construction shall follow the California Building Code and American Concrete Institute guidelines regarding design, mix placement and curing of the concrete. • Cement Type. Type 11 cement or an equivalent shall be used in those concrete elements that will be in contact with the upper soils. • Control Flatwork. Control joints shall be provided , in accordance with American Concrete Institute Guidelines to control cracking of exterior concrete flatwork (patios, walkways, driveways, etc.). Other methods to control cracking shall include careful control of water/cement ratios in the concrete, along with taking appropriate curing precautions during the placement of concrete in hot or windy weather. Retaining Wall Design and Construction Recommendations presented herein apply to typical masonry or concrete vertical retaining walls to a maximum height of 10 feet. Additional review and recommendations shall be required for higher walls. • Foundations for retaining walls embedded a minimum of 18 inches into compacted fill shall be designed using a net allowable bearing capacity of 2,000 psf. An increase of one-third shall be applied when considering short-term live loads (e.g., seismic and Page 53 Resolution Number 6273 wind loads). The passive earth pressure shall be computed as an equivalent fluid having a density of 250 psf per foot of depth, to a maximum earth pressure of 3,000 psf. A coefficient of friction between soil and concrete of 0.30 shall be used with dead load forces. When combining passive pressure and frictional resistance, the passive pressure component shall be reduced by one-third. An equivalent fluid pressure approach shall be used to compute the horizontal active pressure against the wall. The appropriate fluid unit weights are provided below for specific slope gradients of retained materials. • Surface Slope of Equivalent Retained• = , Fluid . Materials•. Pressure' (H:V) (PCF) Level 35 2:1 55 The above equivalent fluid weights do not include other superimposed loading conditions such as expansive soil, vehicular traffic, structures, seismic conditions or adverse geologic conditions. • Wall Backfill and Drainage. The onsite sandy materials possessing a low expansion potential that are used for backfill shall be screened of greater than three inch size gravels. If other materials are present the parameters provided shall be reviewed, and if necessary, modification to the wall designs shall be made. The backfill materials shall be placed in lifts no greater than eight inches in thickness and compacted at 90 percent relative compaction in accordance with ASTM Test Method D1557- 00. Proper surface drainage shall be provided and maintained. Retaining walls shall be provided with an adequate pipe and gravel back drain system to prevent buildup of hydrostatic pressures. Backdrains shall consist of a 4-inch diameter perforated PVC pipe • embedded in a minimum of one cubic foot per lineal foot of 3/8 to one inch clean crushed rock or equivalent, wrapped in filter fabric (Mirafi 140N or an approved equivalent). The drain system shall be connected to a suitable outlet. A minimum of two outlets shall be provided for each drain section. Walls from two to four feet in height shall be drained using localized gravel packs behind weep holes at 10 feet maximum spacing (e.g., approximately 1.5 cubic feet of • gravel in a woven plastic bag). Weep holes shall be provided or the head joints omitted in the first course of block extended above the ground surface. Post Construction • Landscape Maintenance and Planting. Positive surface drainage away from graded slopes shall be maintained and only the amount of irrigation necessary to sustain plant life shall be Page 54 provided for planted slopes. Plants selected for landscaping shall be lightweight, deep-rooted types that require little water and are capable of surviving the prevailing climate. Over watering shall be avoided. The soils shall be maintained in a solid to semisolid state as defined by the materials'Atterberg Limits. Care shall be taken when adding soil amendments to avoid excessive watering. Leaching as a method of soil preparation prior to planting shall not occur. Planting placed adjacent to structures in planter or lawn areas shall be avoided. If used, waterproofing of the foundation and/or subdrains shall occur. • Drainage. Positive site drainage shall be maintained at all times. Drainage shall not flow uncontrolled down any descending slope. Water shall be directed away from foundations and not allowed to pond or seep into the ground. Pad drainage shall be directed toward approved area(s). Positive drainage shall not be blocked by other improvements. A de- watering system shall be implemented if below- grade construction (i.e., basements, etc.) is planned to extend down to or below depths of between nine and 15 feet below existing site grades Implementation and operation (as deemed necessary) of de-watering procedures/equipment both during subterranean construction (if planned) and throughout the lifetime of the structure(s) shall occur. A contractor specializing in the design and implementation of de-watering systems shall be consulted prior to the beginning of construction activities. Plan Review and Construction Observations Site grading, specifications, and foundation plans shall be reviewed by a Geotechnical Engineer, approved by the City, prior to construction to verify conformance with the above recommendations. It is recommended that a Geotechnical Engineer be present during site grading and foundation construction to check for proper implementation of the geotechnical recommendations. The Geotechnical Engineer shall perform at least the following duties: • Observe site clearing and grubbing operations for proper removal of all unsuitable materials. • Observe and test bottom of removals prior to fill placement. • Evaluate the suitability of onsite and import materials for fill placement, and collect soil samples for laboratory testing where necessary. • Observe the fill for uniformity during placement including utility trenches. Also, test the fill for field density and relative compaction. Page 55 Resolution Number 6273 • Observe and probe foundation materials to confirm suitability of bearing materials and proper footing dimensions. GEO-2 Prior to issuance of any grading permit, the Grading Plan shall incorporate all engineering recommendations contained within the Final Soils/Geotechnical Engineering Report for the proposed project during project site design and construction, in order to reduce any potential soil and geotechnical hazards at the project site. These recommendations shall be stipulated in the construction contracts and specifications. GEO-3 Prior to issuance of any building permit for development of each residential lot, the building and engineering plans shall incorporate all engineering recommendations contained within the Final Soils/Geotechnical Engineering Report for the proposed project during lot site design and construction, in order to reduce any potential soil and geotechnical hazards at the residential lots. These recommendations shall be stipulated in the building and engineering plans and specifications. b. Facts in Support of Findings Shallow Groundwater Saturated soils and caving conditions would likely be encountered during remedial grading associated with removal and re-compaction of soils within several feet above, or at any depth below the groundwater table. Depending upon the construction methods employed, dewatering may be required in order to safely excavate the Project site just above and below groundwater, which would likely require some form of lateral support. Compliance with Mitigation Measures GEO-1 and GEO-2 would ensure that potential impacts associated with shallow groundwater would be reduced to a less than significant level. Sloughing or Caving of Excavations During construction of the proposed Project, excavations associated with remedial grading/ground stabilization and underground utilities would encounter unconsolidated/noncohesive artificial fill, as well as saturated paralic soils. If unsupported, these soils would be subject to sloughing and caving, creating a short-term hazard to construction workers and equipment. Compliance with Mitigation Measures GEO-1 and GEO-2 would ensure that potential impacts associated with sloughing or caving of excavations would be reduced to a less than significant level. With regard to cumulative impacts, with the incorporation of GEO-1, GEO- 2, and GEO-3, the Project would not contribute to cumulative impacts. Therefore,with mitigation, any cumulative impact would be less than significant. 3. Expansive Soils—Project Specific and Cumulative The Project may be located on expansive soils creating substantial risks to life or property. In addition, the Project has the potential to contribute to a cumulative impact in this regard. Mitigation is being imposed to ensure any potential expansive soils Project specific or cumulative impact is reduced to a less than significant level. Page 56 a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative impact. Specifically, the following mitigation measures are imposed upon the Project to ensure a less than significant impact: GEO-1 Prior to issuance of any grading permit, the project applicant shall prepare a Final Soils/Geotechnical Engineering Report for review and approval by the City's Engineer. The Final Soils Geotechnical Engineering Report shall be prepared by a professional engineer and certified engineering geologist licensed by the State of California, in consultation with a corrosion engineer, and demonstrate compliance with the following recommendations identified in the Preliminary Geotechnical Evaluation for Proposed Residential Development, prepared by GeoTek, Inc., dated September 12, 2005, and the Geology, Soils, and Seismicity Report in Support of DWP Specific Plan Amendment EIR, Seal Beach California, prepared by D. Scott Magorien, C.E.G. Consulting Engineering Geologist, dated June 27, 2011, and any additional recommendations identified by the City's Engineer. The Preliminary Geotechnical Evaluation and Geology Report are included in Appendix 11.8, Geology, Soils, and Seismicity Data of this EIR and are incorporated by reference into this mitigation measure. The following recommendations shall be addressed and incorporated into the Final Soils Geotechnical Engineering Report: Earthwork Considerations Earthwork and grading shall be performed in accordance with the applicable grading ordinances of the current California Building Code (CBC), and the following recommendations. The Grading Guidelines included in Appendix D of the Preliminary Geotechnical Evaluation for Proposed Residential Development, prepared by GeoTek, Inc., dated September 12, 2005 outline general procedures and do not anticipate all site-specific situations. In the event of conflict, the following recommendations shall supersede those contained in Appendix D of the Preliminary Geotechnical Evaluation for Proposed Residential Development. • Site Clearing. In areas of planned grading or improvements, the site shall be cleared of vegetation, roots, and debris, and properly disposed of offsite. Any holes resulting from site clearing, tree removal, and/or the backhoe trenches excavated shall be replaced with properly compacted fill materials. • Fills. Any import fill shall consist of relatively low-expansive soils (EI<50) and shall be evaluated by a Registered Civil Engineer/Geotechnical Engineer, approved by the City, prior to arrival at the project site. The fill materials shall be compacted in layers no Page 57 Resolution Number 6273 thicker than 8 inches to at least 90 percent of maximum dry density with a moisture content of at least optimum, as determined in accordance with American Society for Testing and Materials (ASTM) Test Method D1557-00. Those areas to receive fill shall be scarified to a depth of 8 inches; moisture conditioned to at least optimum moisture content and recompacted to at least 90 percent of maximum dry density. • Removals. Existing fill materials shall be subject to complete removal and recompaction within the limits of grading. In those areas where the depth of existing fill materials extends below the groundwater table, the upper eight to 10 feet of soil, along with organic and other deleterious materials, shall be removed. If saturated and yielding subgrade conditions are encountered upon removal of the upper soils within those areas exhibiting a shallow ground water surface, the contractor shall place uniform sized, '/.- inch crushed rock within the area exhibiting the "pumping" conditions. The crushed rock shall be properly tracked into the underlying soils such that it is adequately intruded into and interlocks with the soils. The necessary thickness of the crushed rock shall be evaluated during construction. Following the placement and tracking of the gravel layer into the underlying "pumping"soils, Mirafi 600X stabilization fabric (or approved equivalent) shall be placed upon the gravel layer. Fill soils shall then be placed upon the fabric and compacted to a minimum 90 percent relative compaction (based on ASTM test method D1557) until finished grades are reached. The gravel and stabilization fabric shall extend at least 5 feet laterally beyond the limits of the"pumping"areas.These operations shall be performed under the observation and testing of a professional engineer or a certified engineering geologist licensed by the State of California, approved by the City in order to evaluate the effectiveness of these measures and to provide additional recommendations, as warranted. Following the completion of rough grading at the site, settlement monuments shall be installed at finish rough grade. These monuments shall be established based on a known bench mark and their elevations shall be monitored by a licensed land surveyor on a weekly basis. The surveyor's settlement monument data shall be reviewed weekly by the Registered Civil Engineer/Geotechnical Engineer, approved by the City. This monitoring shall continue until the consolidation is deemed to have sufficiently stabilized. Once it has been concluded that the remaining settlement is within acceptable levels, the settlement monuments may be destroyed and fine grading may proceed. Page 58 • Excavation Characteristics. All temporary excavations for grading purposes and installation of underground utilities shall be constructed in accordance with Occupational Safety and Health Administration (OSHA) guidelines. • Expansive Soils. Placement of any clayey soils within three feet of finish grade shall be avoided. Foundation Support • Conventional Foundation Recommendations. In the areas where complete removal and recompaction of the upper soils can be accomplished, the proposed residential structures shall be supported on conventional continuous or isolated spread footings bearing entirely upon properly compacted fill materials. Foundations supporting single story structures shall be constructed with an embedment of at least 12 inches below finish grade, while those supporting two story structures shall be constructed with an embedment of at least 18 inches below finish grade. At these depths, footings shall be designed for an allowable soil bearing value of 2,000 pounds per square foot (psf). This value shall be increased by one- third for loads of short duration, such as wind and seismic forces. Continuous footings supporting single-story structures shall have a minimum width of 12 inches, while those supporting two-story structures shall have a minimum width of 15 inches. Based on geotechnical considerations, footings shall be provided with reinforcement consisting of two No. 4 rebars, one top and one bottom. A minimum width of 24 inches for isolated spread footings shall be provided. Passive resistance to lateral loads shall be computed as an equivalent fluid pressure having a density of 250 psf per foot of depth to a maximum earth pressure of 3,000 psf. A coefficient of friction between soil and concrete of 0.30 shall be used with dead load forces. When combining passive and frictional resistance, the passive pressure component shall be reduced by one- third. • Special Foundation Systems. In the areas where incomplete removals are performed and/or the potential for seismically induced differential settlement exists,special foundation systems such as mat foundations, post- tensioned slabs, or drilled pier foundation systems shall be considered for support of the proposed residential structures. If mat foundations are used to support the proposed residential structures,the mat foundations shall be designed to bridge over voids that may develop under the slab due to differential Page 59 Resolution Number 6273 settlement. The mat foundation shall be founded within compacted fill materials, with a minimum embedment of 18 inches below finish grade. For mats founded on soft, wet, or cohesionless soils, special preparation of the bottom shall be required to support construction traffic. Mat foundations shall be properly reinforced to form a relatively rigid structural unit in accordance with the structural • engineers design. For preliminary design purposes, an uncorrected modulus of subgrade reaction of 100 pounds per cubic inch (pci) shall be assumed. For large foundations, the modulus shall be reduced by 75 percent (i.e., to 25 pci). Actual geotechnical design parameters shall be provided upon completion of a more complete geotechnical evaluation of the proposed building site. If post-tensioned slabs are used to support the proposed residential structures, the structural design of post-tensioned slabs shall follow the recommendations of the Post-Tensioning Institute (PTI) Method and Section 1819 of the 2001 California Building Code (i.e., 1808 [Foundations] and 1808.6.2 [ Slab on Ground Foundations]). Based on the geotechnical data acquired during the subsurface exploration, an allowable bearing capacity of 1,500 psf, and a slab-subgrade friction coefficient of 0.75 shall be used for design of post-tensioned slabs. Final design shall be verified based upon actual soil conditions encountered and results of laboratory testing performed during or at the completion of site grading. If drilled piers are used to support the proposed residential structures, the drilled piers shall be designed utilizing either end-bearing or skin friction design. Drilled piers shall be embedded at least 5 feet within the alluvial materials or 14 feet below the existing ground surface (whichever is deeper). Design of drilled piers subjected to earthquake loading shall consider the effects of downdrag, due to the potential for liquefaction within portions of the fill. Because of the relatively high ground water level, along with the presence of poorly graded sands within the fill and alluvium, temporary casing or bentonite slurry shall be utilized to support the walls of the shaft prior to the placement of concrete. Further, the cleaning of loose slough from the bottom of the shaft excavation shall be warranted for drilled piers that will derive their support from end-bearing conditions. • Seismic Design Parameters. Seismically resistant structural design in accordance with local building ordinances shall be followed during the design of all structures. For the purpose of seismic design, a Type B seismic source (L.A. Basin segment of the Newport- Inglewood Fault) located less than 2 kilometers from the site shall be used. Page 60 • Foundation Setbacks. Where applicable, the following setbacks shall apply to all foundations: o The outside bottom edge of all footings shall be set back a minimum of HI3 (where H is the slope height) from the face of any descending slope. The setback shall be at least seven feet and need not exceed 20 feet. o The bottom of all footings for structures near retaining walls shall be deepened so as to extend below a 1:1 projection upward from the bottom inside edge of the wall stem. o The bottom of any existing foundations for structures shall be deepened so as to extend below a 1:1 projection upward from the bottom of the nearest excavation. • Slab-On-Grade. Where applicable, concrete slabs (including the mat foundations recommended above) shall be a minimum of four inches thick and reinforced as per structural engineer requirements. Control joints shall be provided to help reduce random cracking. Slabs shall be underlain by a four inch thick capillary break layer consisting of clean sand (S.E. of 30 or greater). Where moisture condensation is undesirable, all slabs shall be underlain with a minimum six mil polyvinyl chloride membrane, sandwiched between two layers of clean sand (S.E. 30 or greater), each being at least two inches thick. Care shall be taken to adequately seal all seams and not puncture or tear the membrane. The sand shall be proof rolled. This recommendation is based on soil support characteristics only. The structural engineer shall design the actual slab and beam reinforcement based on expansion indices of the finish grade soils,actual loading conditions, and possible concrete shrinkage. • Soil Corrosivity. A corrosion engineer shall be consulted to provide recommendations for proper protection of buried metal pipes at this site. • Utilities. Due to the project site's susceptibility to liquefaction and a considerable amount of seismically-induced settlement and lateral • spreading, consideration shall be given to "flexible" design for on-site utility lines and connections. Except where extending perpendicular to/under proposed foundations, utility trenches shall be constructed outside a 1:1 projection from the base-of foundations. Trench excavations for utility lines which Page 61 Resolution Number 6273 extend under structural areas shall be properly backfilled and compacted. Utilities shall be bedded and backfilled with clean sand or approved granular soil to a depth of at least one foot over the pipe. This backfill shall be uniformly watered and compacted to a firm condition for pipe support. The remainder of the backfill shall be typical on-site soil or imported soil which shall be placed in lifts not exceeding eight inches in thickness, watered or aerated to 0 to 3 percent above the optimum moisture content, and mechanically compacted to at least 90 percent of maximum dry density (based on ASTM D1557). Concrete Construction Concrete construction shall follow the California • Building Code and American Concrete Institute guidelines regarding design, mix placement and curing of the concrete. • Cement Type.Type 11 cement or an equivalent shall be used in those concrete elements that will be in contact with the upper soils. • Control Flatwork. Control joints shall be provided in accordance with American Concrete Institute Guidelines to control cracking of exterior concrete flatwork (patios, walkways, driveways, etc.). Other methods to control cracking shall include careful control of water/cement ratios in the concrete, along with taking appropriate curing precautions during the placement of concrete in hot or windy weather. Retaining Wall Design and Construction Recommendations presented herein apply to typical masonry or concrete vertical retaining walls to a maximum height of 10 feet. Additional review and recommendations shall be required for higher walls. Foundations for retaining walls embedded a minimum of 18 inches into compacted fill shall be designed using a net allowable bearing capacity of 2,000 psf. An increase of one-third shall be applied when considering short-term live loads (e.g., seismic and wind loads). The passive earth pressure shall be computed as an equivalent fluid having a density of 250 psf per foot of depth, to a maximum earth pressure of 3,000 psf. A coefficient of friction between soil and concrete of 0.30 shall be used with dead load forces. When combining passive pressure and frictional resistance, the passive pressure component shall be reduced by one-third. An equivalent fluid pressure approach shall be used to compute the horizontal active pressure against the wall. The appropriate fluid unit weights are provided below for specific slope gradients of retained materials. Surface„.;Slope, ;•; EquiJatent •_ Retained: ".•. .. Fluid .. Page 62 • Materials Pressure (H:V) (PCF) Level 35 2:1 55 The above equivalent fluid weights do not include other superimposed loading conditions such as expansive soil, vehicular traffic, structures, seismic conditions or adverse geologic conditions. • Wall Backfill and Drainage. The onsite sandy materials possessing a low expansion potential that are used for backfill shall be screened of greater than three inch size gravels. If other materials are present the parameters provided shall be reviewed and if necessary, modification to the wall designs shall be made. The backfill materials shall be placed in lifts no greater than eight inches in thickness and compacted at 90 percent relative compaction in accordance with ASTM Test Method D1557- 00. Proper surface drainage shall be provided and maintained. Retaining walls shall be provided with an adequate pipe and gravel back drain system to prevent buildup of hydrostatic pressures. Backdrains shall consist of a 4-inch diameter perforated PVC pipe embedded in a minimum of one cubic foot per lineal foot of 3/8 to one inch clean crushed rock or equivalent, wrapped in filter fabric (Mirafi 140N or an approved equivalent). The drain system shall be connected to a suitable outlet. A minimum of two outlets shall be provided for each drain section. Walls from two to four feet in height shall be drained using localized gravel • packs behind weep holes at 10 feet maximum spacing (e.g., approximately 1.5 cubic feet of gravel in a woven plastic bag). Weep holes shall be provided or the head joints omitted in the first course of block extended above the ground surface. Post Construction • Landscape Maintenance and Planting. Positive surface drainage away from graded slopes • shall be maintained and only the amount of irrigation necessary to sustain plant life shall be provided for planted slopes. Plants selected for landscaping shall be lightweight, deep-rooted types that require little water and are capable of surviving the prevailing climate. Over watering shall be avoided. The soils shall be maintained in a solid to semisolid state as defined by the materials'Atterberg Limits. Care shall be taken when adding soil amendments to avoid excessive watering. Leaching as a method of soil preparation prior to planting shall not occur. Planting placed adjacent to structures in planter or lawn areas shall be Page 63 Resolution Number 6273 avoided. If used, waterproofing of the foundation and/or subdrains shall occur. • Drainage. Positive site drainage shall be maintained at all times. Drainage shall not flow uncontrolled down any descending slope. Water shall be directed away from foundations and not allowed to pond or seep into the ground. Pad drainage shall be directed toward approved area(s). Positive drainage shall not be blocked by other improvements. A de- watering system shall be implemented if below- grade construction (i.e., basements, etc.) is planned to extend down to or below depths of between nine and 15 feet below existing site grades Implementation and operation (as deemed necessary) of de-watering procedures/equipment both during subterranean construction Of planned) and throughout the lifetime of the structure(s) shall occur. A contractor specializing in the design and implementation of de-watering systems shall be consulted prior to the beginning of construction activities. Plan Review and Construction Observations Site grading, specifications, and foundation plans shall be reviewed by a Geotechnical Engineer, approved by the City, prior to construction to verify conformance with the above recommendations. It is recommended that a Geotechnical Engineer be present during site grading and foundation construction to check for proper implementation of the geotechnical recommendations. The Geotechnical Engineer shall perform at least the following duties: • Observe site clearing and grubbing operations for proper removal of all unsuitable materials. • Observe and test bottom of removals prior to fill placement. • Evaluate the suitability of onsite and import materials for fill placement, and collect soil samples for laboratory testing where necessary. • Observe the fill for uniformity during placement including utility trenches. Also, test the fill for field density and relative compaction. • Observe and probe foundation materials to confirm suitability of bearing materials and proper footing dimensions. GEO-2 Prior to issuance of any grading permit, the Grading Plan shall incorporate all engineering recommendations contained within the Final Soils/Geotechnical Engineering Report for the proposed project during project site design and construction, in order to reduce any potential soil and geotechnical hazards at the project site. These Page 64 recommendations shall be stipulated in the construction contracts and specifications. GEO-3 Prior to issuance of any building permit for development of each residential lot, the building and engineering plans shall incorporate all engineering recommendations contained within the Final Soils/Geotechnical Engineering Report for the proposed project during lot site design and construction, in order to reduce any potential soil and geotechnical hazards at the residential lots. These recommendations shall be stipulated in the building and engineering plans and specifications. b. Facts in Support of Findings The laboratory tests performed for the Project site indicate that the soils encountered are anticipated to exhibit "low to medium" expansion potential. The potential for expansive soils to impact new development is considered low. The Preliminary Geotechnical Evaluation recommends that placement of any clayey (expansive) soils imported to the Project site be avoided within three feet of finish grades. Compliance with Mitigation Measures GEO-1 and GEO-2 would ensure that potential impacts associated with expansive soils imported to the Project site would be reduced to a less than significant level. With regard to cumulative impacts, with the incorporation of GEO-1, GEO- 2, and GEO-3, .the Project would not contribute to cumulative impacts. Therefore,with mitigation, any cumulative impact would be less than significant. 4. Corrosive Soils—Project Specific and Cumulative Development of the Project could encounter corrosive soils potentially resulting in damage to foundations and buried pipelines. The Project has the potential to also contribute to a cumulative impact in this regard. However, with the implementation of mitigation, any potential impact will be reduced to a level of insignificance. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative impact. Specifically, the following mitigation measures are imposed upon the Project to ensure a less than significant impact: GEO-1 Prior to issuance of any grading permit, the project applicant shall prepare a Final Soils/Geotechnical Engineering Report for review and approval by the City's Engineer. The Final Soils Geotechnical Engineering Report shall be prepared by a professional engineer and certified engineering geologist licensed by the State of California, in consultation with a corrosion engineer, and demonstrate compliance with the following recommendations identified in the Preliminary Geotechnical Evaluation for Proposed Residential Development, prepared by GeoTek, Inc., dated September 12, 2005, and the Geology, Soils, and Seismicity Report in Support of DWP Specific Plan Amendment EIR, Seal Beach California, prepared by D. Scott Magorien, C.E.G. Consulting Engineering Geologist, dated June 27, 2011, and any additional recommendations identified by the City's Engineer. The Preliminary Geotechnical Evaluation and Page 65 Resolution Number 6273 Geology Report are included in Appendix 11.8, Geology, Soils, and Seismicity Data of this EIR and are incorporated by reference into this mitigation measure. The following recommendations shall be addressed and incorporated into the Final Soils Geotechnical Engineering Report: Earthwork Considerations Earthwork and grading shall be performed in accordance with the applicable grading ordinances of the current California Building Code (CBC), and the following recommendations. The Grading Guidelines included in Appendix D of the Preliminary Geotechnical Evaluation for Proposed Residential Development, prepared by GeoTek, Inc., dated • September 12, 2005 outline general procedures and do not anticipate all site-specific situations. In the event of conflict, the following recommendations shall supersede those contained in Appendix D of the Preliminary Geotechnical Evaluation for Proposed Residential Development. • Site Clearing. In areas of planned grading or improvements, the site shall be cleared of vegetation, roots, and debris, and properly disposed of offsite. Any holes resulting from site clearing, tree removal, and/or the backhoe trenches excavated shall be replaced with properly compacted fill materials. • Fills. Any import fill shall consist of relatively low-expansive soils (EI<50) and shall be evaluated by a Registered Civil Engineer/Geotechnical Engineer, approved by the City, prior to arrival at the project site. The fill materials shall be compacted in layers no thicker than 8 inches to at least 90 percent of maximum dry density with a moisture content of at least optimum, as determined in accordance with American Society for Testing and Materials (ASTM) Test Method D1557-00. Those areas to receive fill shall be scarified to a depth of 8 inches; moisture conditioned to at least optimum moisture content and recompacted to at least 90 percent of maximum dry density. • Removals. Existing fill materials shall be subject to complete removal and recompaction within the limits of grading. In those areas where the depth of existing fill materials extends below the groundwater table, the upper eight to 10 feet of soil, along with organic and other deleterious materials, shall be removed. If saturated and yielding subgrade conditions are encountered upon removal of the upper soils within those areas exhibiting a shallow ground water surface, the contractor shall place uniform sized,' - inch crushed rock within the area exhibiting the "pumping" conditions. The crushed rock shall be properly tracked into the underlying soils such that it is Page 66 adequately intruded into and interlocks with the soils. The necessary thickness of the crushed rock shall be evaluated during construction. Following the placement and tracking of the gravel layer into the underlying"pumping"soils, Mirafi 600X stabilization fabric (or approved equivalent) shall be placed upon the gravel layer. Fill soils shall then be placed upon the fabric and compacted to a minimum 90 percent relative compaction (based on ASTM test method D1557) until finished grades are reached. The gravel and stabilization fabric shall extend at least 5 feet laterally beyond the limits of the"pumping"areas. These operations shall be performed under the observation and testing of a professional engineer or a certified engineering geologist licensed by the State of California, approved by the City in order to evaluate the effectiveness of these measures and to provide additional recommendations, as warranted. Following the completion of rough grading at the site, settlement monuments shall be installed at finish rough grade. These monuments shall be established based on a known bench mark and their elevations shall be monitored by a licensed land surveyor on a weekly basis. The surveyor's settlement monument data shall be reviewed weekly by the Registered Civil Engineer/Geotechnical Engineer, approved by the City. This monitoring shall continue until the consolidation is deemed to have sufficiently stabilized. Once it has been concluded that the remaining settlement is within acceptable levels, the settlement monuments may be destroyed and fine grading may proceed. • Excavation Characteristics. All temporary excavations for grading purposes and installation of underground utilities shall be constructed in accordance with Occupational Safety and Health Administration (OSHA) guidelines. • Expansive Soils. Placement of any clayey soils within three feet of finish grade shall be avoided. Foundation Support • Conventional Foundation Recommendations. In the areas where complete removal and recompaction of the upper soils can be accomplished, the proposed residential structures shall be supported on conventional continuous or isolated spread footings bearing entirely upon properly compacted fill materials. Foundations supporting single story structures shall be constructed with an embedment of at least 12 inches below finish grade, while those supporting two story structures shall be constructed with an embedment of at least 18 Page 67 Resolution Number 6273 inches below finish grade. At these depths, footings shall be designed for an allowable soil bearing value of 2,000 pounds per square foot (psf). This value shall be increased by one- third for loads of short duration, such as wind and seismic forces. Continuous footings supporting single-story structures shall have a minimum width of 12 inches, while those supporting two-story structures shall have a minimum width of 15 inches. Based on geotechnical considerations, footings shall be provided with reinforcement consisting of two No. 4 rebars, one top and one bottom. A minimum width of 24 inches for isolated spread footings shall be provided. Passive resistance to lateral loads shall be computed as an equivalent fluid pressure having a density of 250 psf per foot of depth to a maximum earth pressure of 3,000 psf. A coefficient of friction between soil and concrete of 0.30 shall be used with dead load forces. When combining • passive and frictional resistance, the passive pressure component shall be reduced by one- third. • Special Foundation Systems. In the areas where incomplete removals are performed and/or the potential for seismically induced differential settlement exists, special foundation systems such as mat foundations, post- tensioned slabs, or drilled pier foundation systems shall be considered for support of the proposed residential structures. If mat foundations are used to support the proposed residential structures, the mat foundations shall be designed to bridge over voids that may develop under the slab due to differential settlement. The mat foundation shall be founded within compacted fill materials, with a minimum embedment of 18 inches below finish grade. For mats founded on soft, wet, or cohesionless soils, special preparation of the bottom shall be required to support construction traffic. Mat foundations shall be properly reinforced to form a relatively rigid structural unit in accordance with the structural engineers design. For preliminary design purposes, an uncorrected modulus of subgrade reaction of 100 pounds per cubic inch (pci) shall be assumed. For large foundations, the modulus shall be reduced by 75 percent (i.e., to 25 pci). Actual geotechnical design parameters shall be provided upon completion of a more complete geotechnical evaluation of the proposed building site. If post-tensioned slabs are used to support the proposed residential structures, the structural design of post-tensioned slabs shall follow the recommendations of the Post-Tensioning Institute (PTI) Method and Section 1819 of the 2001 California Building Code (i.e., 1808 [Foundations] and 1808.6.2 [ Slab on Ground Page 68 Foundations]). Based on the geotechnical data acquired during the subsurface exploration, an allowable bearing capacity of 1,500 psf, and a slab-subgrade friction coefficient of 0.75 shall be used for design of post-tensioned slabs. Final design shall be verified based upon actual soil conditions encountered and results of laboratory testing performed during or at the completion of site grading. If drilled piers are used to support the proposed residential structures, the drilled piers shall be designed utilizing either end-bearing or skin friction design. Drilled piers shall be embedded at least 5 feet within the alluvial materials or 14 feet below the existing ground surface (whichever is deeper). Design of drilled piers subjected to earthquake loading shall consider the effects of downdrag, due to the potential for liquefaction within portions of the fill. Because of the relatively high ground water level, along with the presence of poorly graded sands within the fill and alluvium, temporary casing or bentonite slurry shall be utilized to support the walls of the shaft prior to the placement of concrete. Further, the cleaning of loose slough • from the bottom of the shaft excavation shall be warranted for drilled piers that will derive their support from end-bearing conditions. • Seismic Design Parameters. Seismically resistant structural design in accordance with local building ordinances shall be followed during the design of all structures. For the purpose of seismic design, a Type B seismic source (L.A. Basin segment of the Newport- Inglewood Fault) located less than 2 kilometers from the site shall be used. • Foundation Setbacks. Where applicable, the following setbacks shall apply to all foundations: o The outside bottom edge of all footings shall be set back a minimum of H13 (where H is the slope height) from the face of any descending slope. The setback shall be at least seven feet and need not exceed 20 feet. o The bottom of all footings for structures near retaining walls shall be deepened so as to extend below a 1:1 projection upward from the bottom inside edge of the wall stem. o The bottom of any existing foundations for structures shall be deepened so as to extend below a 1:1 projection upward from the bottom of the nearest excavation. Page 69 Resolution Number 6273 • Slab-On-Grade. Where applicable, concrete slabs (including the mat foundations recommended above) shall be a minimum of four inches thick and reinforced as per structural engineer requirements. Control joints shall be provided to help reduce random cracking. Slabs shall be underlain by a four inch thick capillary break layer consisting of clean sand (S.E. of 30 or greater). Where moisture condensation is undesirable, all slabs shall be underlain with a minimum six mil polyvinyl chloride membrane, sandwiched between two layers of clean sand (S.E. 30 or greater), each being at least two inches thick. Care shall be taken to adequately seal all seams and not puncture or tear the membrane. The sand shall be proof rolled. This recommendation is based on soil support characteristics only. The structural engineer shall design the actual slab and beam • reinforcement based on expansion indices of the finish grade soils, actual loading conditions, and possible concrete shrinkage. • Soil Corrosivity. A corrosion engineer shall be consulted to provide recommendations for proper protection of buried metal pipes at this site. • Utilities. Due to the project site's susceptibility to liquefaction and a considerable amount of seismically-induced settlement and lateral spreading, consideration shall be given to "flexible" design for on-site utility lines and connections. Except where extending perpendicular to/under proposed foundations, utility trenches shall be constructed outside a 1:1 projection from the base-of foundations. Trench excavations for utility lines which extend under structural areas shall be properly backfilled and compacted. Utilities shall be bedded and backfilled with clean sand or approved granular soil to a depth of at least one foot over the. pipe. This backfill shall be uniformly watered and compacted to a firm condition for pipe support. The remainder of the backfill shall be typical on-site soil or imported soil which shall be placed in lifts not exceeding eight inches in thickness,watered or aerated to 0 to 3 percent above the optimum moisture content, and mechanically compacted to at least 90 percent of maximum dry density (based on ASTM D1557). Concrete Construction Concrete construction shall follow the California Building Code and American Concrete Institute guidelines regarding design, mix placement and curing of the concrete. Page 70 • Cement Type. Type 11 cement or an equivalent shall be used in those concrete elements that will be in contact with the upper soils. • Control Flatwork. Control joints shall be provided in accordance with American Concrete Institute Guidelines to control cracking of exterior concrete flatwork (patios, •walkways, driveways, etc.). Other methods to control cracking shall include careful control of water/cement ratios in the concrete, along with taking appropriate curing precautions during the placement of concrete in hot or windy weather. Retaining Wall Design and Construction Recommendations presented herein apply to typical masonry or concrete vertical retaining walls to a maximum height of 10 feet. Additional review and recommendations shall be required for higher walls. Foundations for retaining walls embedded a minimum of 18 inches into compacted fill shall be designed using a net allowable bearing capacity of 2,000 psf. An increase of one-third shall be applied when considering short-term live loads (e.g., seismic and wind loads). The passive earth pressure shall be computed as an equivalent fluid having a density of 250 psf per foot of depth, to a maximum earth pressure of 3,000 psf.A coefficient of friction between soil and concrete of 0.30 shall be used with dead load forces. When combining passive pressure and frictional resistance, the passive pressure component shall be reduced by one-third. An equivalent fluid pressure approach shall be used to compute the horizontal active pressure against the wall. The appropriate fluid unit weights are provided below for specific slope gradients of retained materials. • • • Surface-Slope • Equivalent :Retained•. Fluid Materials • Pressure.' (H:1). . (PCF) Level 35 2:1 55 The above equivalent fluid weights do not include other superimposed loading conditions such as expansive soil, vehicular traffic, structures, seismic conditions or adverse geologic conditions. • Wall Backfill and Drainage. The onsite sandy materials possessing a low expansion potential that are used for backfill shall be screened of • greater than three inch size gravels. If other materials are present the parameters provided shall be reviewed and if necessary, modification to the wall designs shall be made. The backfill materials shall be placed in lifts no greater than eight inches in thickness and compacted at 90 percent relative compaction in accordance with ASTM Test Method D1557- Page 71 Resolution Number 6273 00. Proper surface drainage shall be provided and maintained. Retaining walls shall be provided with an adequate pipe and gravel back drain system to prevent buildup of hydrostatic pressures. Backdrains shall consist of a 4-inch diameter perforated PVC pipe embedded in a minimum of one cubic foot per lineal foot of 3/8 to one inch clean crushed rock or equivalent, wrapped in filter fabric (Mirafi 140N or an approved equivalent). The drain system shall be connected to a suitable outlet. A minimum of two outlets shall be provided for each drain section. Walls from two to four feet in height shall be drained using localized gravel packs behind weep holes at 10 feet maximum spacing (e.g., approximately 1.5 cubic feet of gravel in a woven plastic bag). Weep holes shall be provided or the head joints omitted in the first course of block extended above the ground surface. Post Construction • Landscape Maintenance and Planting. Positive surface drainage away from graded slopes shall be maintained and only the amount of irrigation necessary to sustain plant life shall be provided for planted slopes. Plants selected for landscaping shall be lightweight, deep-rooted types that require little water and are capable of surviving the prevailing climate. Over watering shall be avoided. The soils shall be maintained in a solid to semisolid state as defined by the materials'Atterberg Limits. Care shall be taken when adding soil amendments to avoid excessive watering. Leaching as a method of soil preparation prior to planting shall not occur. Planting placed adjacent to structures in planter or lawn areas shall be avoided. If used, waterproofing of the foundation and/or subdrains shall occur. • Drainage. Positive site drainage shall be maintained at all times. Drainage shall not flow uncontrolled down any descending slope. Water shall be directed away from foundations and not allowed to pond or seep into the ground. Pad drainage shall be directed toward approved area(s). Positive drainage shall not be blocked by other improvements. A de- watering system shall be implemented if below- grade construction (i.e., basements, etc.) is planned to extend down to or below depths of between nine and 15 feet below existing site grades Implementation and operation (as deemed necessary) of de-watering procedures/equipment both during subterranean construction (if planned) and throughout the lifetime of the structure(s) shall occur. A contractor specializing in the design and implementation of de-watering systems Page 72 shall be consulted prior to the beginning of construction activities. Plan Review and Construction Observations Site grading, specifications, and foundation plans shall be reviewed by a Geotechnical Engineer, approved by the City, prior to construction to verify conformance with the above recommendations. It is recommended that a Geotechnical Engineer be present during site grading and foundation construction to check for proper implementation of the geotechnical recommendations. The Geotechnical Engineer shall perform at least the following duties: • Observe site clearing and grubbing operations for proper removal of all unsuitable materials. • Observe and test bottom of removals prior to fill placement. • Evaluate the suitability of onsite and import materials for fill placement, and collect soil samples for laboratory testing where necessary. • Observe the fill for uniformity during placement including utility trenches. Also, test the fill for field density and relative compaction. • Observe and probe foundation materials to confirm suitability of bearing materials and proper footing dimensions. GEO-2 Prior to issuance of any grading permit, the Grading Plan shall incorporate all engineering recommendations contained within the Final Soils/Geotechnical Engineering Report for the proposed project during project site design and construction, in order to reduce any potential soil and geotechnical hazards at the project site. These recommendations shall be stipulated in the construction contracts and specifications. GEO-3 Prior to issuance of any building permit for development of each residential lot, the building and engineering plans shall incorporate all engineering recommendations contained within the Final Soils/Geotechnical Engineering Report for the proposed project during lot site design and construction, in order to reduce any potential soil and geotechnical hazards at the residential lots. These recommendations shall be stipulated in the building and engineering plans and specifications. b. Facts in Support of Findings Corrosive soils contain chemical constituents that can react with construction materials, such as concrete and ferrous metals, that may cause damage to foundations and buried pipelines. According to the Preliminary Geotechnical Report and Geology Report contained in the Appendices to the EIR, near surface soils within the Project site are considered highly corrosive to ferrous metals in contact with these soils. Building Code Subsection 313.13 Page 73 Resolution Number 6273 requires steel or galvanized steel to be protected by at least double spiral wrapping, half overlapping with 10 mil plastic tape (total 40 mils cover) or approved equal. The Preliminary Geotechnical Report also recommends, at a minimum, that buried metal piping be protected with suitable coatings, wrapping, or seals. Mitigation Measure GEO-1 requires a corrosion engineer to be consulted during preparation of the Final Soils/Geotechnical Engineering Report. Compliance with the Building Code and Mitigation Measure GEO-1 would reduce potential impacts associated with corrosive soils to a less than significant level. With regard to cumulative impacts,with the incorporation of GEO-1, GEO- 2, and GEO-3, the Project would not contribute to cumulative impacts. Therefore,with mitigation, any cumulative impact would be less than significant. H. HAZARDS AND HAZARDOUS MATERIALS 1. Potential Release of Hazardous Materials During Construction — Prolect Specific and Cumulative Short-term construction activities have the potential to create a significant hazard to the public or environment through accident conditions involving the release of hazardous materials. This impact has the potential to also contribute to a cumulative impact. However, mitigation is imposed to ensure any impact is reduced to a level of insignificance. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative construction related hazardous release impact. Specifically, the following mitigation measures are imposed upon the Project to ensure a less than significant impact: HAZ-1 Prior to demolition activities, an asbestos survey shall be conducted by an Asbestos Hazard Emergency Response Act (AHERA) and Cal OSHA certified building inspector to determine the presence or absence of asbestos containing-materials (ACMs). If ACMs are located, abatement of asbestos shall be completed prior to any activities that would disturb ACMs or create an airborne asbestos hazard. Asbestos removal shall be performed by a State certified asbestos containment contractor in accordance with the South Coast Air Quality Management District(SCAQMD) Rule 1403. HAZ-2 If paint is separated from building materials (chemically or physically) during demolition of the structures, the paint waste shall be evaluated independently from the building material by a qualified Environmental Professional. If lead-based paint is found, abatement shall be completed by a qualified Lead Specialist prior to any activities that would create lead dust or fume hazard. Lead-based paint removal and disposal shall be performed in accordance with California Code of Regulation Title 8, Section 1532.1, which specifies exposure limits, exposure monitoring and respiratory protection, and mandates good worker practices by workers exposed to lead. Contractors performing lead-based paint removal shall provide evidence of abatement activities to the City Engineer. Page 74 HAZ-3 The Applicant shall confirm whether or not utilities are present on-site. Should utilities be present and would need to be removed, the Applicant shall remove on-site utilities in consultation with the City Engineer. Should hazardous materials be anticipated in association with utility removal, the Applicant and the City Engineer shall further consult with the Orange County Health Care Agency regarding proper utility removal and worker safety protections. HAZ-4 Prior to site disturbance within the 1st Street right-of-way, the contractor shall contact Dig Alert (Underground Service Alert of Southern California) in order to confirm the location of the existing oil pipe lines. The contractor shall coordinate with the owner(s) of the existing oil pipe lines in order to ensure that a rupture during disturbance activities does not occur. HAZ-5 If unknown wastes or suspect materials are discovered during construction by the contractor that are believed to involve hazardous waste or materials, the contractor shall comply with the following: • Immediately cease work in the vicinity of the suspected contaminant, and remove workers and the public from the area; • Notify the City Engineer of the City of Seal Beach; • Secure the area as directed by the City Engineer; and • Notify the Orange County Health Care Agency's Hazardous Materials Division's Hazardous Waste/Materials Coordinator (or other appropriate agency specified by the City Engineer). The Hazardous Waste/Materials Coordinator shall advise the responsible party of further actions that shall be taken, if required. HAZ-6 The contractor shall verify that all imported soils, and on-site soils proposed for fill, are not contaminated with hazardous materials above regulatory thresholds in consultation with a Phase II/Site Characterization Specialist. If soils are determined to be contaminated above regulatory thresholds, these soils shall not be used as fill material within the boundaries of the project site, unless otherwise specified by a regulatory agency that has jurisdiction to oversee hazardous substance cleanup (e.g., Department of Toxic Substances Control, Regional Water Quality Control Board, Orange County Health Care Agency,etc.). b. Facts in Support of Findings One of the means through which human exposure to hazardous substances could occur is through accidental release. Incidents that result in an accidental release of hazardous substances into the environment can cause contamination of soil, surface water, and groundwater, in addition to any toxic Page 75 Resolution Number 6273 fumes that might be generated. Human exposure of contaminated soil or water can have potential health effects based on a variety of factors, such as the nature of the contaminant and the degree of exposure. Construction activities associated with development of the project could release hazardous materials into the environment through reasonably foreseeable upset and accident conditions. Site disturbance/demolition activities could expose workers to a variety of potentially hazardous materials. Implementation of Mitigation Measures HAZ-1 through HAZ-4 would reduce potential impacts from site disturbance/demolition activities that would result in accidental conditions at the Project site. In particular, HAZ-1 would require that an asbestos survey be conducted to determine the presence or absence of asbestos containing materials. HAZ-2 would require paint waste to be evaluated to determine if lead based paint is present, and require compliance with the California Code of Regulation provision on the removal and disposal of lead based paint. HAZ-3 would require certain procedures be followed in the removal of any on-site utilities. HAZ-4 would require contact with Dig Alert to confirm the location of the existing oil pipe line. Finally, if unknown wastes or suspect materials are discovered during construction by the contractor, which he/she believes may involve hazardous wastes/materials, the contractor would be required to complete the following components of Mitigation Measure HAZ-5: • Immediately stop work in the vicinity of the suspected contaminant, removing workers and the public from the area; • Notify the City Engineer of the City of Seal Beach; • Secure the areas as directed by the City Engineer; and • Notify the Orange County Health Care Agency's Hazardous Waste/Materials Coordinator. Further, implementation of the proposed Project would require the import of fill materials, which could include contaminated soils. With implementation of the recommended Mitigation Measure HAZ-6, the contractor, in consultation with a Phase II/Site Characterization Specialist, would be required to verify that all imported fill materials and on-site materials that are used for fill, do not include hazardous substances above regulatory thresholds. With implementation of Mitigation Measures HAZ-1 through HAZ-6 and compliance with applicable Federal, State, and local regulatory requirements pertaining to hazardous materials, potential impacts would be reduced to less than significant levels. Lastly, with regard to cumulative impacts, cumulative projects are not anticipated to result in a cumulatively considerable hazardous materials impact, as other projects propose recreation, mixed use (residential, retail, hotel, restaurant, theater, and a marine/science learning center), as well as a grocery store use (Fresh 'n Easy). The Project could contribute, cumulatively (although not significantly), to a hazard involving the transport of hazardous materials during construction. Other cumulative projects could result in the transport of hazardous materials during site disturbance/demolition/remedial activities. Handling, transport, and disposal of these materials are regulated by the DTSC, CaIEPA, CaIOSHA, HCA, and OCFA. The construction contractor, on a project- by-project basis, would be subject to the requirements of the DTSC goveming removal actions. DISC regulations require specific hazardous materials handling methods, truck haul routes, and schedules to minimize potential exposure during hazardous materials removal actions. Compliance with all applicable Federal and State laws related to the transportation of hazardous materials would reduce the likelihood and severity of accidents during transit, thereby ensuring that a less than significant cumulatively considerable impact would occur as a result of implementation of the proposed Project. Page 76 HYDROLOGY AND WATER QUALITY 1. Construction Water Quality Impact — Project Specific and Cumulative Grading, excavation, and construction activities associated with the proposed Project could impact water quality. Additionally, the Project, coupled with other cumulative projects has the potential to cause a cumulative impact in this regard. With the imposition of mitigation, any potential construction water quality impact will be eliminated. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative construction related water quality impact. Specifically, the following mitigation measures are imposed upon the Project to ensure a less than significant impact: HWQ-1 Prior to Grading Permit issuance and as part of the project's compliance with the NPDES requirements, a Notice of Intent (NOI) shall be prepared and submitted to the State Water Resources Quality Control Board (SWRCB), providing notification and intent to comply with the State of California General Permit. HWQ-2 The proposed project shall conform to the requirements of an approved Storm Water Pollution Prevention Plan (SWPPP) (to be applied for during the Grading Plan process) and the NPDES Permit for General Construction Activities No. CAS000002, Order No, 2009-0009-DWQ, including implementation of all recommended Best Management Practices (BMPs), as approved by the State Water Resources Quality Control Board (SWRCB). HWQ-3 The range of Best Management Practices (BMPs) outlined in Section 5.0 of the Department of Water and Power Specific Plan Amendment Environmental Impact Report Hydrology and Water Quality Technical Appendix (Hydrology Study), prepared by RBF Consulting (November 2011), and/or equivalent and related provisions shall be incorporated into the project's Storm Water Pollution Prevention Plan (SWPPP). The Hydrology Study is included in Appendix 11.10, Hydrology and Water Quality Technical Study of this EIR and is incorporated by reference into this mitigation measure. HWQ-4 Upon completion of project construction, the project applicant shall submit a Notice of Termination (NOT) to the State Water Resources Quality Control Board (SWRCB) to indicate that construction is completed. b. Facts in Support of Findings In order to reduce the amount of on-site exposed soil that will occur during Project construction, graded areas would be protected against erosion once they are brought to final grade through the implementation of Best Management Practices(i.e., hydraulic mulching, hydroseeding, soil binders, etc.). Furthermore, Page 77 Resolution Number 6273 • the Project would be required to prepare and submit a Notice of Intent(Mitigation Measure HWQ-1) and a Storm Water Pollution Prevention Plan (SWPPP) (Mitigation Measure HWQ-2) to the State Water Resources Control Board (SWRCB) demonstrating compliance with the Construction General NPDES Permit. Construction activities for the proposed Project would be subject to inspection by the City Department of Public Works. The General Permit requires that non-storm water discharges from construction sites be eliminated or reduced to the maximum extent practicable, that a SWPPP be developed governing construction activities for the proposed Project, and that routine inspections be performed of all storm water pollution prevention measures and control practices being used at the site, including inspections before and after storm events. The Hydrology Study in the Appendices of the EIR identifies potential BMPs that may be outlined in the Project's SWPPP, required as part of Mitigation Measure HWQ-3. These BMPs include, but are not limited to, minimizing the removal of trees, hydraulic mulching, hydroseeding, silt fencing, sediment trapping, and construction road stabilization. Upon completion of the Project, the applicant would be required to submit a Notice of Termination• to the State Water Resources Control Board (SWRCB) (Mitigation Measure HWQ-4) to indicate that construction is completed. Construction activities associated with the proposed Project would have a less than significant impact on surface water quality and would not significantly impact the beneficial uses of receiving waters with compliance with Mitigation Measures HWQ-1 through HWQ-4, which would ensure adherence to construction requirements per the State. With implementation of Mitigation Measures HWQ-1 through HWQ-4, short-term water quality impacts would be reduced to less than significant levels. With regard to cumulative impacts, cumulative projects have the potential to affect water quality during construction. Development of the Project, along with related cumulative projects, would result in increased potential for short-term construction water quality impacts within the area. However, the proposed Project would be required to implement various mitigation measures that would ensure that the Project impacts would not be cumulatively considerable and thus less than significant. 2. Operational Water Quality Impact — Project Specific and Cumulative Implementation of the Project could potentially result in increase run-off amounts that may degrade water quality. Further, the Project, coupled with other cumulative projects, has the potential to cause a cumulative impact in this regard. However, mitigation will be imposed to ensure a less than significant impact. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative operational water quality impact. Specifically, the following mitigation measures are imposed upon the Project to ensure a less than significant impact: HWQ-5 Prior to issuance of a grading permit for Tentative Tract Map 17425, the project applicant shall provide detailed basin sizing calculations and design drawings demonstrating the detention basins adequately mitigate the 2-year and 25-year storm events, consistent with the hydrology analysis provided in Section 5.0 of the Department of Water and Power Specific Plan Amendment Environmental Impact Report Hydrology and Water Quality Technical Appendix (Hydrology Study), prepared by RBF Consulting, (November 2011).The Hydrology Study is included in Appendix 11.10, Hydrology and Water Page 78 Quality Technical Study of this EIR and is incorporated by reference into this mitigation measure. HWQ-6 In conjunction with final project design and when precise engineering occurs, the project- applicant shall demonstrate no adverse flooding impacts would occur at the intersection of Marina Drive and 1st Street during the 100-year storm event. The analysis shall be submitted to the City Engineer prior to recordation of the Final Tentative Tract Map 17425 and prior to issuance of the grading permit. HWQ-7 Prior to issuance of a grading permit for Tentative Tract Map 17425, the project applicant shall submit a Final Water Quality Management Plan for approval by the City Engineer that complies with the requirements of the latest Orange County Public Works Drainage Area Management Plan. HWQ-8 Prior to initiation of grading activities for the open space/passive park, the City shall prepare a • Water Quality Management Plan for approval by the City Engineer that complies with the requirements of the latest Orange County Public Works Drainage Area Management Plan. b. Facts in Support of Findings As indicated in Table 5.11-2 in the EIR, the increase in imperviousness associated with implementation of the tentative tract map would increase peak flow rates in both the 2-year and 25-year storm events at the Marina Drive storm drain and San Gabriel River outlet structure above existing conditions. The increase in peak flow rates is considered a significant impact unless mitigated. As a result of the increased flow rates, measures would be required to reduce the proposed Project flow rates to equal to or less than existing conditions. Mitigation Measure HWQ-5 would require the Applicant to provide detailed basin sizing calculations and design drawings demonstrating the detention basins adequately mitigate the 2-year and 25-year storm events. Further, as indicated in Table 5.11-3 of the EIR,with implementation of the detention facilities, runoff during the 2-year and 25-year storm events associated with the proposed Project would be less than or equal to existing conditions. No additional mitigation of the 2-year and 25-year storm events would be required, and impacts would be less than significant in this regard. However, verification that no adverse flooding impacts would occur at the intersection of Marina Drive and 1st Street during the 100-year storm event would be required pursuant to Mitigation Measure HWQ-6. Compliance with Mitigation Measure HWQ-6 would ensure that any adverse impacts associated with the 100-year storm event would be mitigated to a less than significant level. The SWRCB Municipal NPDES Storm Water Permit for the County of Orange and the incorporated cities of Orange County requires applicants to prepare a Water Quality Management Plan (WQMP) to manage post construction storm water runoff associated with development. The proposed Project is considered a"Priority Project"in accordance with the 2011 Countywide Model WQMP, as it represents a "New development project that creates 10,000 square feet or more of impervious surface." A Preliminary Water Quality Management Plan (PWQMP) has been prepared for the Project. The PWQMP describes the development and its operations, identifies potential sources of storm water pollution, and recommends appropriate Best Management Practices (BMPs) or pollution control measures to reduce the discharge of pollutants in storm water runoff. Recommended BMPs include site design, source control, Page 79 Resolution Number 6273 and low impact development. The Final WQMP, approved by the City, would provide the final BMPs applicable to the proposed project (Mitigation Measure HWQ-7). Implementation of the Final WQMP would ensure that post construction water quality impacts, including impacts to beneficial uses of receiving waters, associated with the Project and future residential development would be reduced to the Maximum Extent Practicable. Post-construction water quality impacts within the northern portion of the Project site would be reduced to a less than significant level with implementation of Mitigation Measure HWQ-7. The southern portion of the Project site would involve open space/passive park and existing private driveway. It is assumed the private driveway would continue to generate general pollutants, such as suspended solids/sediments, nutrients, heavy metals, pathogens, pesticides, oil and grease, toxic organic compounds, and trash and debris. The City would be required to prepare a WQMP to address post-construction operations associated with future development of the passive park through Mitigation Measure HWQ-8. Compliance with the WQMP and Mitigation Measure HWQ-8 would reduce potential water quality impacts associated with the passive park to a less than • significant level. With regard to cumulative impacts, cumulative projects have the potential to affect water quality. Development of the Project, along with related cumulative projects, would result in increased potential for long-term operational water quality impacts within the area. However, the proposed Project would be required to implement various mitigation measures that would ensure that the Project impacts would not be cumulatively considerable and thus less than significant. In response to the Planning Commission recommendations, the Applicant proposed refinements to the Project as discussed in Section III of these findings. As discussed in Environmental Analysis of the Alternative Site Plan: Department of Water and Power Specific Plan Amendment dated June 15, 2012, which is hereby incorporated by this reference, the modifications to the drainage improvements in the second revised tract map would not result in additional hydrology or water quality impacts. The refinements include an extended detention basin large enough to mitigate the 25 year storm event to pre- development levels and storm drain alignments within the project have been realigned closer to the detention basin. Primary project entrances are still located on the 1st Street side across from Central Way and on the north Marina Drive side, across and slightly westerly from the existing Riverbeach entry located on the north side of Marina Drive. The relocation of the entries does not affect the drainage of the project. J. PUBLIC SERVICES AND UTILITIES 1. Fire Protection—Project Specific and Cumulative Project implementation could result in the need for additional fire protection facilities and personnel. The Project, coupled with other cumulative projects could also contribute to a cumulative impact in this regard. With the imposition of mitigation,this impact will be reduced to a level of insignificance. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative fire protection services impact. Specifically, the following mitigation measure is imposed upon the Project to ensure a less than significant impact: PSU-1 The following conditions required by the Orange County Fire Authority (OCFA) shall be incorporated into the plans and specifications for the proposed Tentative Tract Map No. 17425, and Page 80 submitted to OCFA for approval prior to the issuance of building permits: • All traffic signals on public access ways shall include optical preemption devices. • All electrically operated gates shall include emergency opening devices, as approved by OCFA. • Project plans shall adhere to OCFA standard conditions with regards to water supply, built-in fire protection systems, road grades, road width, access, and building materials. b. Facts in Support of Findings As more fully detailed in the EIR, the Orange County Fire Authority (OCFA) has indicated that staffing levels are currently adequate to serve the project site. Due to the stations' close proximity to the project site, OCFA has indicated the response time from the nearest fire station (Station #44) would be within the goal time measurement of seven minutes and 20 seconds.At this time, there is no facility or staffing needs at the fire station's that would be required in order to serve the Project site. After reviewing the proposed Project, OCFA has specified requirements related to traffic signals, electric gates, and other standard conditions to be implemented as part of the Project as specified in Mitigation Measure PSU-1. Therefore,with implementation of Mitigation Measure PSU-1, impacts related to fire protection would be reduced to less than significant levels. With regard to cumulative impacts, three of the four cumulative projects would be in OCFA's jurisdiction,while the fourth would be under that of the Long Beach Fire Department. These projects propose additional recreational and commercial uses that would require fire protection services from OCFA. These projects would be required to comply with all applicable laws, ordinances, and development codes related to fire protection and emergency services. OCFA has indicated that implementation of the proposed Project would not require the expansion of fire protection facilities or services, and that adequate services exist to serve the Project site. However, OCFA has specified standard conditions that the Project must adhere to, which are contained within Mitigation Measure PSU- 1. It is anticipated that existing OCFA fire protection services would be adequate to serve the proposed Project as well as the two cumulative projects within OCFA's jurisdiction. However, as service level needs increase due to increased population or other factors affecting the community, OCFA would determine • whether or not additional fire protection staff is needed. Therefore, overall cumulative impacts would be less than significant with the implementation of mitigation. 2. Wastewater Services—Project Specific and Cumulative Project implementation could result in significant impacts to wastewater services. The Project, along with other cumulative projects, also has the potential to pose a cumulative impact. Mitigation will be implemented to reduce any potential impact to the extent feasible, and to a less than significant level. a. Findings Changes or alterations have been required in, or incorporated into, the Project that avoid or substantially lessen any potential project specific and cumulative wastewater services impact. Specifically, the following mitigation measure is imposed upon the Project to ensure a less than significant impact: Page 81 Resolution Number 6273 PSU-2 The Utility Plan for Tentative Tract Map No. 17425 shall include the following sewer pipeline provisions, which shall be subject to the review and approval of the City's Public Works Engineer: • A new eight-inch sewer pipeline from the project site, across 1st Street, connecting to the existing six-inch pipeline shall be constructed within the alley to the east of the project site between 1st and 2nd Streets; and • The northern portion (from Central Way to the alley parallel to and southwest of Central Avenue) of the existing pipeline within the alley to the east of the project site between 1st and 2nd Streets shall be upgraded to an eight-inch pipeline. The new and upgraded sewer pipeline dimensions and locations shall be determined in consultation with the City's Public Works Engineer. b. Facts in Support of Findings The Project would result in increased wastewater generation from the proposed 48 single family units proposed as part of the Project. However, this increase will not constrain the capacity of the existing wastewater infrastructure with implementation of Mitigation Measure PSU-2. In particular, Mitigation Measure PSU-2 will require the Applicant to install a new eight inch sewer pipeline and upgrade an existing pipeline. The proposed Project would also not exceed wastewater treatment requirements of the Santa Ana Regional Water Quality Control Board. The project would be required to pay applicable sewer connection fees to the Orange County Sewer District (OCSD) as required by OCSD Ordinance No. OCSD-31 (average of$4,671 per single-family residence). In sum, project compliance with the Mitigation Measure PSU-2, the City's Municipal Code, and OCSD Ordinance No. OCSD-31 would ensure the Project would have less than significant impacts on the existing sewer system. As such, impacts regarding wastewater associated with Project implementation would be reduced to less than significant levels. With regard to cumulative impacts, the cumulative projects within Seal Beach would also result in minimal wastewater generation as they involve a park expansion and grocery store. The 2nd Street and Pacific Coast Highway project would be served by the Long Beach Water Department and would not contribute to the proposed Project's cumulative wastewater impacts. The proposed Project as well as cumulative projects would be required to comply with wastewater treatment requirements of the Santa Ana and Los Angeles RWQCBs. The Project and cumulative projects would also be required to pay applicable sewer connection fees to OCSD as required by OCSD Ordinance No. OCSD-31. Therefore, the Project's contribution to cumulative impacts to wastewater facilities would be less than significant with implementation of Mitigation Measure PSU-2. VII. Project Alternatives The City of Seal Beach considered a range of reasonable alternatives for the proposed Project including, Alternative 1 — No Project/No Build Alternative, Alternative 1.2 —No Project/1996 Department of Water and Power Specific Plan Alternative,and Alternative 2—Modified Layout Alternative. In addition to the alternatives cited above and discussed below, an Alternative Location Alternative was considered by rejected as infeasible and Page 82 was not studied in the EIR. The basis for rejecting this Alternative Location Alternative as infeasible stems from the fact that the Project Applicant own the land on which the proposed Project is proposed to be built. The Project Applicant is not anticipated to acquire another property solely for the purpose of developing this Project. Rather, developing the proposed Project on the proposed Project site is the objective of the Applicant. Therefore, alternative locations not already owned by the Applicant were not analyzed in the EIR. Alternatives 1, 1.2 and 2 that were analyzed in the EIR are discussed below. A. ALTERNATIVE 1 —NO PROJECT/NO BUILD ALTERNATIVE The No Project/No Build Alternative would retain the Project site in its current condition. With this. Alternative, the DWP Specific Plan Area would remain vacant and unimproved. The landscaping and sidewalk on the sewer parcel would be retained.The single-family dwelling and boat parking area on the California Everglades property, and the 1st Street Right-of-Way would not be demolished or removed, but would rather remain. as they exist. Under this Alternative, the driveway parcel would continue to provide access to the River End Staging Area and public beach, and the bike trail/river parcel would continue to be used for regional recreational and drainage purposes, as with the proposed Project. Under the No Project/No Build Alternative, the DWP Specific Plan boundaries and land use categories would not be amended. The Specific Plan Area boundaries would not be modified to include the California Everglades parcel and the 1st Street Right-of-Way parcel, or to exclude the small triangular parcel. The California Everglades parcel would not be dedicated to the City for public Right-of-Way use. None of the proposed amendments to the Seal Beach General Plan (General Plan) or Official Zoning Map/Zoning Code would be • implemented. The sewer and park/open space parcels would not be utilized for open space/passive park uses. None of the improvements proposed as part of the tentative tract map would be constructed. The northern portion of the Property would not be subdivided into 48 single-family lots. A new network of public local streets and alleys, and the proposed drainage and water quality improvements would not be constructed. Additionally, the proposed hardscape (i.e., sidewalks and entrance driveways) and landscape improvements would not be installed. In general, impacts over the proposed Project would be reduced with the No Project/No Build Alternative. However, the No Project/No Build Alternative would not attain most of the project's basic objectives. A residential project that preserves the public views of the water and extends the existing urban form of the Old Town Neighborhood would not be constructed. Open space and recreational opportunities for the residents of Seal Beach would not be enhanced. Additionally, sustainable design and construction practices would not be incorporated. The No Project/No Build Alternative would attain one project objective: to preserve public access to the beach through continued use of the San Gabriel River Bike Trail and 1st Street beach parking lot(i.e.,the RESA). • As the Project, as refined, would reduce the number of residential homes from 48 to 32, and would avoid the previous significant and unavoidable aesthetic impacts, the City Council finds this as a basis for selecting the Project, as refined, over this Alternative. Under CEQA, findings on alternatives are not required if all of the project's impacts are mitigated to less than significant levels. See Mira Mar Mobile Community v. City of Oceanside, 119 Cal. App. 4th 477, 497 (2004); Rio Vista Farm Bureau Center v. County of Solano, 5 Cal. App. 4th 351, 379 (1992). Page 83 Resolution Number 6273 B. NO PROJECT/1996 DWP SPECIFIC PLAN ALTERNATIVE The No Project/1996 DWP Specific Plan Alternative proposes development of what would be reasonably expected to occur in the foreseeable future if the project were not approved, based on the property's current adopted entitlement,which is the DWP Specific Plan. Under this Alternative,the project's proposed changes to the Specific Plan boundaries and land use categories would not occur. The boundaries would not be modified to include the California Everglades parcel and the 1st Street Right- of-Way parcel, or to exclude the small triangular parcel. The area within the Specific Plan would not increase to 10.9 acres, rather would remain 10.7 acres. As indicated in Table 7-1 of the EIR, this Alternative varies from the proposed Project in that it proposes an additional 1.1 acres of Open Space, no Residential uses, and approximately 3.2 acres of Visitor Serving uses (i.e., a 150-room hotel). None of the improvements proposed as part of the tentative tract map would be constructed. The northern portion of the property would not be subdivided into 48 single-family lots, and a new network of public local streets and alleys would not be constructed with this Alternative. With this Alternative, the California Everglades parcel would not be dedicated to the City for public Right-of-Way use. As with the proposed Project, the sewer and park/open space parcels would be utilized for open space/passive park uses under this Alternative. As with the proposed Project, drainage and water quality improvements would be constructed. Additionally, hardscape (i.e_, sidewalks and entrance driveways) and landscape improvements would be installed. Due to a similar development footprint, the grading and excavation proposed for this Alternative would be similar to the proposed Project. In general, impacts would be worse under this Alternative as compared to the proposed Project. In particular, the No Project/1996 DWP Specific Plan Alternative would be environmentally inferior to the proposed Project as it would result in a new significant and unavoidable long-term impact from new hotel related light sources. It would also fail to eliminate the existing significant and unavoidable visual character and quality impact, and the existing light and glare impact associated with Project traffic. This Alternative may also result in increased traffic impacts, long-term air quality impacts form mobile emissions, increased greenhouse gas emissions impacts from mobile sources, and potentially greater noise impacts. The remaining impacts would be similar under this Alternative as compared to the proposed Project. The No Project/1996 DWP Specific Plan Alternative would not attain the project's fundamental objective to construct a residential project that preserves the public views of the water and extends the existing urban form of the Old Town Neighborhood. The Alternative would attain the remaining Project objectives to enhance the open space and recreational opportunities for the residents of Seal Beach, and incorporate sustainable design and construction practices. The No Project/1996 DWP Specific Plan Alternative would also preserve public access to the beach through continued use of the San Gabriel River Bike Trail and 1st Street beach parking lot. As the Project, as refined, would reduce the number of residential homes from 48 to 32, and would avoid the previous significant and unavoidable aesthetic impacts, the City Council finds this as a basis for selecting the Project, as refined, over this Alternative. Under CEQA, findings on alternatives are not required if all of the project's impacts are mitigated to less than significant levels. See Mira Mar Mobile Community v. City of Oceanside, 119 Cal.App. 4th 477, 497 (2004); Rio Vista Farm Bureau Center v. County of Solano, 5 Cal.App. 4th 351,379(1992). C. MODIFIED LAYOUT ALTERNATIVE Under the Modified Layout Alternative, the DWP Specific Plan boundaries and land use categories would be amended, similar to the proposed Project. The Specific Plan Area boundaries would be modified to include a portion of the California Everglades parcel (Area 7) and the it Street Right-of-Way parcel (Area Page 84 8), and to exclude the small triangular parcel (Area 6). A portion of the California Everglades parcel would be dedicated to the City for public Right-of-Way use. All of the proposed amendments to the General Plan and Official Zoning Map/Zoning Code would be implemented. The sewer and park/open space parcels would be utilized for open space/passive park uses. Most of the improvements proposed as part of the tentative tract map analyzed by the Draft EIR would be constructed under the Modified Layout Alternative. However, under this Alternative, the northern portion of the property would be subdivided into 41 single-family lots, as opposed to the 48 single-family lots initially proposed.. Comparatively, this seven (7) unit reduction would represent an approximately 15 percent reduction in dwellings. Under this Alternative, the orientation of the residential lots would be modified to provide front yards along 1st Street, as opposed to the side yards initially proposed. Additionally, the Central Way Right-of-Way prolongation proposed under this Alternative would be relocated approximately 50 feet to the south, to align with the existing Central Way Right-of-Way (located east of 1u Street), as opposed to the Right-of-Way ('B' Street) initially proposed. These modifications to the lot layout are proposed in an effort to avoid the initial project's significant and unavoidable long-term impacts involving visual character and light/glare from vehicle headlights. A new network of public local streets and alleys, and the proposed drainage and water quality improvements would be constructed under this Alternative, similar to the proposed Project. Additionally, the proposed hardscape (i.e., sidewalks and entrance driveways) and landscape improvements would be installed. The Project's proposed grading would similarly occur under this Alternative. Most, if not all of the features of the Modified Layout Alternative have been incorporated into the Project, as refined. For instance, the proposed Central Way Right-of-Way prolongation would align with the existing Central Way Right-of- Way(located east of 1st Street). In addition, the orientation of_residential lots would be modified to provide front yards along 1n Street. These refinements eliminate all of the initial project's significant and unavoidable long-term impacts, including visual character and light/glare from vehicle headlights. Moreover, density has been reduced to 32 residential lots. In general, impacts would be reduced under this Alternative over the proposed Project. For example, the significant and unavoidable light and glare impact associated with traffic headlights would be avoided with this Modified Layout Alternative. Additionally, traffic, air quality, and greenhouse gas emissions would be reduced over the proposed Project. All.other impact areas would remain the same. The Modified Layout Alternative would attain all of the Project's objectives. A residential project that preserves the public views of the water and extends the existing urban form of the Old Town Neighborhood would be constructed. Open space and recreational opportunities for the residents of Seal Beach would be enhanced. Additionally, sustainable design and construction practices would be incorporated. The Modified Layout Alternative would also preserve public access to the beach through continued use of the San Gabriel River Bike Trail and 1st Street beach parking lot. As the Project, as refined, would reduce the number of residential homes from 48 to 32, and would avoid the previous significant and unavoidable aesthetic impacts, the City Council finds this as a basis for selecting the Project, as refined, over this Alternative. Under CEQA, findings on alternatives are not required if all of the project's impacts are mitigated to less than significant levels. See Mira Mar Mobile Community v. City of Oceanside, 119 Cal. App. 4th 477, 497 (2004); Rio Vista Farm Bureau Center v. County of Solano, 5 Cal.App.4th 351, 379(1992). D. ENVIRONMENTALLY SUPERIOR ALTERNATIVE The No Project/No Build Alternative would be the environmentally superior alternative because it would avoid or lessen the majority of impacts associated Page 85 Resolution Number 6273 with the proposed Project. CEQA Guidelines 15126.6(e)(2) requires, however, that when the No Project Alternative is the environmentally superior alternative, another environmentally superior alternative must be identified. The Draft BR therefore identified the Modified Layout Alternative as the environmentally superior alternative because it reduced the number of residential homes from the 48 included in the project as originally proposed to 41 homes while avoiding the significant and unavoidable aesthetic impacts. The Project as refined in response to the Planning commission's recommendations, however, would reduce the number of residential homes even further from 48 to 32 while avoiding the previously identified significant and unavoidable aesthetic impacts associated with the project as originally proposed and without creating any new impacts. Moreover, because the Project, as refined in response to the Planning commission's recommendations, would result in 9 fewer homes than the Modified Layout Alternative, it will likely result in impacts that are incrementally lesser in number or degree than those caused by the Modified Layout Alternative. The City Council therefore finds that the Project, as refined in response to the Planning commission's recommendations, is less impactful than the Modified Layout Alternative. Page 86 EXHIBIT B MITGATION MONITORING AND REPORTING PROGRAM (SEE ATTACHMENT 8 TO THE JUNE 25, 2012 CITY COUNCIL AGENDA STAFF REPORT)