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HomeMy WebLinkAboutCell Genesys Development Initial Study and Proposed MND 10-2001INITIAL STUDY AND PROPOSED MITIGATED NEGATIVE DECLARATION Application Number 01-032 CITY OF SOUTH SAN FRANCISCO CELL GENESYS DEVELOPMENT PREPARED BY LAMPHIER-GREGORY 1944 EMBARCADERO WAY OAKLAND, CA 94606 OCTOBER 2001 LAMPHIER -GREGORY Errata Lamphier-Gregory received utility infrastructure information subsequent to printing and binding of the Cell Genesys Initial Study/Proposed Mitigated Negative Declaration. A consultant under contract to the City of South San Francisco is currently completing a study of the sewage collection and transport system for the area, and will provide input for sewage treatment plant upgrades. The results of this study will help provide definitive information about any required improvements to utility infrastructure which would be required for the Cell Genesys Project. When this information is available, it will be possible to determine if the Project would have a significant impact on the City's infrastructure. The Project's requirements are shown on the following page. Any infrastructure improvement requirements shall be paid for on a pro rata basis by the proponents of the the Cell Genesys development in order to reduce their impact to a less than significant level. Lamphier -Gregory • 1944 Embarcadero Oakland, CA 94606 • Phone 510-535-6690 • FAX 510-535-6699 10/02/2001 15:21 6506296639 SSF PLANNING DRAWBRIDGElFORBES, October 1, 2001 1vlr. Thomas C. Sparks Chief Planner Department Of Economic And Community Development 400 Grand Avenue P.O. Box 711 South San Francisco, California 94083 o~ r ° ~ Zoos p~ANJVI/yG RE: Cell. Genesys Corporate Headquarters and Research facility, located at 500 Forbes Boulevard, South San Francisco, California. Dear Mr. Sparks: In response to the Planning Department's request for the sewage load requirements for Cell Genesys's new headquarters acrd research faciliry, I have prepared the following updated summary. Forbes Wing: • 190 gpm with 3" water meter, 4" water service, and 6" sanitary sewer to the Forbes Wing. • Natural Gas estimate - 10 million btu's at 3psi pressure downstream of gas meter. Allerton Wiag: • 21 S gpm with 3" water meter, 4" water service, and 6" sanitary sewer to the Allerton Wing. Natural gas estimate - 12 million btu's at 3-psi pressure downstream of gas ureter. Sewage Discharge Volumes: • 2 million gallons per month discharge. PAGE 02 LLC 2O L.A FERRERA TERRACE • SAN FRANCISCO. CA 94133 PHONE: 415-391.44J0 • FAx.: 415-391-4430 10/02/2001 15:21 650B296639 SSF PLANNING PAGE 03 I hope this helps clarify Cel] Ger~esy's requirements for the 500 Forbes Boulevazd site. If you have any questions or need additional information, please give me a call. Sincerely, Mark Pearson ~ Partner Cc: Steve Carlson Barbara Hawkins TABLE OF CONTENTS Page MITIGATED NEGATIVE DECLARATION ...............................................................................................5 APPLICATION ................................................................................................................................................. .. 5 APPLICANT ..................................................................................................................................................... .. 5 PROJECT OBJECTIVE ....................................................................................................................................... .. 5 LOCATION ..................................... 5 ................................................................................................................. .. PROJECT DESCRIPTION ................................................................................................................................... .. 5 POTENTIALLY SIGNIFICANT IMPACTS REQUIRING MITIGA'I'ION .................................................................... .. 5 MITIGATION MEASURES FOR POTENIIALLY SIGNIFICANT IMPACTS ............................................................... .. 7 ENVIRONMENTAL FACTORS POTENTIALLY AFFECTED .................................................................................. 10 CHIEF PLANNER'S DE'I'ERIviINATION .............................................................................................................. 10 PUBLIC REVIEW ............................................. 11 .................................................................................................. LEAD AGENCY ............................................ . 12 .. ................................................................................................. DETERMINATION ..................................................................................................... 13 ....................................... INITIAL STUDY ........................................................................................................... 14 .............................. GENERAL INFORMATION ................................................................................................................................ 14 PROJECT SITE DESCRrnTIOIV ........................................................................................................................... 14 Location and Setting ............................................................................................ 14 ....................................... Circulation Characteristics ......................................................................................................................... 14 Zoning ....................................... ................................................................................................................ 14 Site Ownership ......................................................................................................... . 15 . ................................ PROJECT CONTEXT AND DESCRII'TION .......................................................................................................... 15 Required Discretionary Approvals ............................................................................................................. 15 INITIAL STUDY CHECKLIST ..................................................................................................................19 AESTHETICS ........................................................................................................................................... 19 AGRICULTURE RESOURCES ................................................................................................................... 25 AIR QUALITY ......................................................................................................................................... 26 BIOLOGICAL RESOURCES ....................................................................................................................... 32 CULTURAL R.ESOI.IRCES ......................................................................................................................... 37 GEOLOGY AND SOIIS ............................................................................................................................ 39 HAZARDS AND HAZARDOUS MATERIALS .............................................................................................. 53 HYDROLOGY AND WATER QUALITY .................................................................................................... 58 INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT • PAGE I LAND USE AND PLANNING ................................................................................................................... 63 MINERAL RESOURCES ............................................................................................................................ 68 NOISE .................................................................................................................................................... 69 POPULATION AND HOUSING ................................................................................................................ 74 PUBLIC SERVICES ................................................................................................................................... 75 RECREATION ......................................................................................................................................... 76 TRANSPORTATION/TRAFFIC ................................................................................................................. 77 UTII.I'TIES AND SERVICE SYSTEMS ........................................................................................................... 86 MANDATORY FINDINGS OF SIGNIFICANCE ........................................................................................... 89 REFERENCES ..................................................................... .............91 BIBLIOGRAPHY ................................................................................................................................................ 91 PERSONAL COMMUNICATIONS ....................................................................................................................... 92 REPORT AUTHORS .......................................................................................................................................... 92 APPENDICES .............................................................................................................................................93 INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT • PAGE II TABLE OF CONTENTS (continued) Page LIST OF FIGURES 1. PROJECT LOCATION ...................................................................................................................................16 2. PROJECT SITE PLAN .....................................................................................................................................17 3. FRONT OF EXISTING BUII.DING ..................................................................................................................21 4. EXTERIOR OF EXLSTING BUII,DING ..............................................................................................................21 5. INTERIOR OF EXLSTING BUII.DnvG ...............................................................................................................22 b. SOUTHERN PORTION OF EXISTING BUII.DING .............................................................................................22 7. BUII.DING ADJACENT TO PROJECT $TTE ...................................................................................................... 23 8. VEGETATION ON NORTHEAST CORNER OF PROJECT $TTE ......................................................................... 34 9. VEGETATION ON EAST END OF PROJECT STTE ............................................................................................35 10. VEGETATION ALONG FORBES BOUI.EVARD .................................................................................................35 11. VEGETATION AT FORBES /ALLERTON INTERSECTION ................................................................................36 12. VEGETATION AT NORTHWEST CORNER OF PROJECT $TTE .......................................................................... 36 13. TEST BORING LOCATION$ ...........................................................................................................................42 LIST of TABI.Es 1. COMPACTION REQUIItEMENTS ................................................................................................ 46 2. GRADATION REQUIREMENTS FOR CAPII.LARY BREAK AND $AND ................................................... 48 3. PAVEMENT SECTION DESIGN .....................................................................................................................49 INRIAL STUDY / MRIGATED NEGATNE DECLARATION CELL GENESYS DEVELOPMENT • PAGE III This page was intentionally left blank. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT • PAGE IV MITIGATED NEGATIVE DECLARATION APPLICATION This Mitigated Negative Declaration (Application Number 01-032) is for the proposed Cell Genesys corporate headquarters office development. APPLICANT The Project Applicant is Cell Genesys, Inc. PROJECT OBJECTIVE The Project objective is to establish a corporate headquarters complex for Cell Genesys, Inc. on the site of an abandoned airline storage facility. LOCATION The Project site is located in an eastern portion of South San Francisco, east of Highway 101, at 500 Forbes Boulevard, where Forbes Boulevard intersects with Allerton Avenue. PROJECT DESCRIPTION The Project would involve demolition of an existing building at the Project site and construction of a new 154,000 square foot corporate headquarters and biotechnology research building with 435 open at grade parking spaces. POTENTIALLY SIGNIFICANT IMPACTS REQUIRING MITIGATION The following is a summary of potential Project impacts. Refer to the Initial Study Checklist and/or Appendix A of this document for a more detailed discussion of these impacts. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE) SITE OWNERSHII' Drawbridge Forbes, LLC is the property owner. PROJECT CONTEXT AND DESCRIPTION The Project Site Platt is shown in Figure 2. REQUIRED DISCRETIONARY APPROVALS The Project would require a use permit and a tree removal permit. 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I, O ~, ~ ~~ ~ ~~ ~ ~ I I ~~ ~~ 3 , ~ • ~okA~~ 001 AM =+"OOZ ~~ Gt,~ ~ ~ ~ 4f~~J~ ~~ "~~~~ a0flbtlH ~ ~` r I ~ ^ rf ~ ~ -+ I I ~ / lea Q . v -~s=~~, a,`~ d~~ ~ ~,~,~er~ '~ b 31b~ s~aadr~~ ~ ~~ ~ = Q ~" ~~ z • ~ '~il~i o ~ ~ tlm o, Q ~~ °Ln>> ~ ssj ~ a~vs~ ~ t N O~ ~ v! 2. ~ v ~ y ,y vp ~~ - Q- ~ u« _, j ~ ~ ~ F ~~ ~ - Q ~ ~ CV c'') INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE ~ 6 -~ 25'-0" 14 PKG. SPACES ®B'-6" = 119'-0` 5'- " 10 PKG. SPACES ®8'-6"=B5'-0" 5i- " 11 PKG. SPACES ®8'-6"=102'-0" 5'- " 15 PKG. SPACES ®8'-6'=136'-0" 1'-1"_ 88'-0" o - - a, N 40'00'00" W 526.43' - .._ Uo °°• °' . of o a ~" 1 5~-0" ~ 5'-8 I /2" 4 I I j ~ 5'-0~ 9 PKG. ACE ®6'-6"=76'-6 _ 13 PKG. SPACES ®B'-6"=110'-6" - ' 30'-0' IS'-0" 25'-6" 2 '-0" 18'-0' IB'-2" 25'-0' 1B'-0" 1B'-0' 25'-0" I w z' g ~ ~ ~ g 1 o ce _ I _ I Iv m ~ _-- -- ------' ~ - -.o ---------------- ----- ~ I l o ~ --- I I Iv 4 I ' ~ j ~ ° ~ j ~ ' I I I "I I I I I ~' ~ I ~ I ° I I 1 I s I ~ -I I x i~ __ I - . + . - . + . + . - . + . - . + . - . + . . 4 I I I I I -~ I' ~ I I I I I I A I I I I I I I II iJ u ~ I r ~ I ~ ~ I ~ I I z3o'_d. I I I ; ~ it ~I 'I it - 20'-0' _ 25' a" i _ ~ ~ _ ~ _ ~ _ ~ _ ~ _ ~ I' - I I 1 ~1 I - , 1 1 1 I Im w i~ r I~ I o I I Ilo'-b" I _ 'I II % 1~1 n D r I r ....~ ° I i ' I ' ~~ r i I m I I li 'i ~~~ ~ ~~ / ' c ` I I \ / ~` r ~ \ I ~ \ \\ q r ~ / 1\ 0 19 _0 \ \ / I I \\ \ $ -0 25.E \\ 1 o- i_ \\ 25_0" 10`0 ` '~- o -"\ Z~Im, \\ I \ '~ • ~\ I ~ b, \ I \ ~• \ \ ~ ~ ~ o. \ ~ o \\ ~ _ \ ~ -\ \ \ \a ~ y '~~~. A ~~ ~ \ 1\5~~` 1\ \ \1 a R \ ~ ~ ~ k ~ \ \ \ 1 `s~s\ ~ ~ \~ ~ ~ 130 0 i~k~/ ~" 1\ /\\ i ~ \ ~ ~ k I g ~ ~ ti5a ~ ~ ko \ k ' •-16.6 \ \ \ 9GF ~ tid'0 `~~ ~ ~ \ `~ _d PKG acES ®$ ,~ a ~ "~ ~ \ ~.k Q 9 0, ~ ~ \v' I 4 ~~ ~ ~~ i ~GESaO_fi'1p2_ '/-'~~~~ya~r 1p 9,1?15 6 5;0 .-~, ~ ; " ~- ~ S®0 6 ~ - ~" \ 6 -j6 - \ - ° ~ ~ \ SP pCE ~ f ~= 5 ', / 9 PKG. m ~ \ ~ ~ ~ ~ SPACES 5 -0 ®® ~~ ~ SPp o. ~ 9 PKG. _ a m ~// J <121''6 5 ~0 ~ AGES 9 6 ,6" $ \ 15 PKG ~' n 26 } ~ z apt{ "°- ~ 3 H ~ N N ~ b ~ ,¢py ~ R7 11''~~ ~ ~ ~ ~ F.~ N o "gyp ~ j ~ ~l ~iv~~ ~ ~ ~ ~ br'J G~ ~ ~ in ~ ~ Rp a ro q ao ~ ~ 1~~~~ ~~~~ Z ~ ~ ~ ~ ~ g~ ~~ ~ ~° 2 S a cn ~ ~ ~r ~~ INITIAL STUDY CHECKLIST The Checklist portion of the Initial Study begins below, with explanations of each answer. A "no impact" response indicates, for example, that no displacement of existing housing would occur due to the Project, because no housing units now exist within the Project site which might need to be removed to enable the Project to proceed. A "less than significant" response indicates that while there may be potential for an environmental impact, there are standard procedures or regulations in place, or other features of the Project as proposed, which would limit the extent of this impact to a level of "less than significant." Responses that indicate that the impact of the project would be "less than significant with mitigation" indicate that mitigation measures, identified in the subsequent discussion, will be required as a condition of Project approval in order to effectively reduce potential Project-related environmental effects to a level of "less than significant." Environmental Factors and Focused Questions for potentially Less Than Less Than Determination of Environmental Impact Significant Significant with Significant No Impact Mkigation Impact Impact I. AESTHETICS -Would the Project: a) Have a substantial adverse effect on a scenic ( ~ ( ~ ( ~ (/ vista? b) Substantially damage scenic resources, ( ~ ( ~ ( ~ (/~ including, but not limited to, trees, rock outcroppings, and historic buildings within a state scenic highway? c) Substantially degrade the existing visual ( ~ ( ~ ( ~ (/ character or quality of the site and its surroundings? d) Create a new source of substantial light or ( ~ ( ~ (/~ glare, which would adversely affect day or nighttime views in the area? INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 'I 9 Setting' South San Francisco's urban character is one of contrasts within a visually well defined setting. San Bruno Mountain to the north, the ridge along Skyline Boulevard to the west, and the San Francisco Bay to the east provide the City with distinctive edges. The City is contained in almost a bowl like fashion by hills on three sides. The City's terrain ranges from the flatlands along the water to hills east and north. Hills are visible from all parts of the City, and Sign Hill and San Bruno Mountain (which is outside City limits) in the distance are visual landmarks. Much of the City's topography is rolling, resulting in distant views from many neighborhoods. Geographically, the City is relatively small, extending approximately two miles in a north-south direction and about five miles from east to west. South San Francisco's industrial roots are reflected in its urban character, especially in its eastern parts. Almost two fifths of South San Francisco's land is occupied by industrial and warehousing uses. The Project site is located in the East of 101 planning sub-area of South San Francisco. The East of 101 area was part of the first industrial development in South San Francisco about 100 years ago. Since then, the area has undergone many transformations. Pioneering industrial uses, such as steel manufacturing, and meat packaging gave way to industrial park and warehousing and distribution uses that came to dominate the area in the SOs and 60s. The recent emergence of modern office buildings marks the third major wave of land use change in the area. The newly emerging office areas are unique in their uses of consistent and conscious street tree planting, while the rest of the City, including downtown, is almost bereft of street trees. Older manufacturing uses, industrial park structures and tilt-up warehousing buildings can all be found in the area. Blocks are generally very large in size and the area has a very stark industrial look. Numerous abandoned railroad spurs are present. The Project site is located at 500 Forbes Boulevard, where Forbes Boulevard intersects with Allerton Avenue. The shell of an abandoned building currently exists on the site. Site Description. The existing building's front entrance along Forbes Boulevard is shown in Figure 3, while Figures 4 and 5 show exterior and interior portions of the remaining structure. Figure 6 illustrates a southern portion of the Project site. The cyclone fencing located where the asphalt in the picture ends is the Project site boundary. On the other side of the fence is an abandoned railroad right-of--way that is the site of a proposed recreational trail. Figure 7 is a picture of the See's Candies facility adjacent to the Project site. Additional pictures of the Project site are included in the Biological Resources section of this document. Dyett & Bhatia, South San Francisco General Plan: Existing Conditions and Planning Issues, 1997, p.42, 410, 4 15. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE ZO Figure 3 ~"'' "'.~: ~'= ;x_w~.-_ --- -- Front of Existing Building Figure 4 Exterior of Existing Building ~in)innil:uuii . ,,,,, 1 INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 2'I Figure 5 • ~ ' iY1 _ ., Interior of Existing Building ~` - .. - - -, ~ _ ~. __ _ _ ~ ~~ \ ~ i - }* _. Figure 6 Southern Portion of Project Site ~., 4 '~ Yt {/ ..~ ~i 1 ~ '• V' G. ~`?a.. ! p c ~•~ ~=~ a ar. ~a _- -- ') ~. ',i "'ri ~' ~Y. '.si ;y _ } .. r O ~' L S L•? ~ ~ ~ r~i• j 4' -'4 ~.i ~1 NCI .n t ,~ ~~, ;~~~_: t .:: INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE ZZ Figure 7 Building Adjacent to Project Site ~- yf.~ -1 ~~ a) Scenic Vistas Impact Threshold of Significance: For the purpose of assessing impacts of a proposed project on scenic vistas, the threshold of significance is exceeded when a project would result in the obstruction of a designated public vista, or in the placement Of an arguably offensive or negative-appearing object within such a vista. Any clear conflict with a General Plan policy or other adopted planning policy regarding scenic vistas would also be considered a potentially significant adverse environmental impact. The Project site is not located within any formally designated scenic vista. Therefore, the proposed Project would have no impact on a scenic vista. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 23 b) Scenic Resources Impact Threshold of Significance: Any Project-related action that would substantially damage scenic resources (i.e., trees, rock outcroppings, and historic buildings within a state scenic highway), would be regarded as a significant environmental impact. The Project would have no impact on scenic resources within a state scenic highway since it is not located on a state scenic highway. c) Visual Character Impact Threshold of Significance.• The Project would have a significant environmental impact if it were to substantially degrade the existing visual character or quality of the site and its surroundings. The proposed Project would be located in an area whose visual characteristics primarily consist of large industrial and business park uses. The Project, as a large office complex would improve the visual character of the site or its surroundings. It would replace a vacant structure with an updated building and provide additional landscaping. Therefore the Project would have no negative impact on visual character. d) Light or Glare Impact Threshold of Significance: The Project related creation of any new source of substantial light or glare that would adversely affect day or nighttime views in the area would. be regarded as a significant environmental impact. Establishment of the Cell Genesys Development and its surrounding grounds would involve installation of light standards at various locations on the site. Specific lighting design features have not been determined as of yet. However, lighting designs should employ fixtures that would cast light in a downward direction, and building materials should not be sources of substantial glare. If this is done, the amount of light and glare emanating from the Project site would be considered less than significant. No sources of daytime glare would be associated with the Project. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE Z4 Environmental Factors and Focused Questions for Potentially Less Than Less Than Determination of Environmental Impact Significant Sign~caM with Significant No Impact Mitigation Impact Impact II. AGRICULTURE RESOURCES: In determining whether impacts to agricultural resources are significant environmental effects, lead agencies may refer to the California Agricultural Land Evaluation and Site Assessment Model (1997) prepared by the California Dept. of Conservation as an optional model to use in assessing impacts on agriculture and farmland. Would the Project: a) Convert Prime Farmland, Unique Farmland, or ~ ~ ~ ~ ( ~ ~ /~ Farmland of Statewide Importance (Farmland), as shown on the maps prepared pursuant to the Farmland Mapping and Monitoring Program of the California Resources Agency, to non- agricultural use? b) Conflict with existing zoning for agricultural use, ~ ~ ( ~ ~ ~ ~ /~ or a Williamson Act contract? c) Involve other changes in the existing ( ~ ~ ~ ~ ~ ~ / environment which, due to their location or nature, could result in conversion of Farmland, tonon-agricultural use? a) Converting Prime Farmland The Project area is in the midst of an urban area that has already been developed in a mix of residential and commercial uses. No Prime Farmlands, Unique Farmlands or Farmlands of Statewide Importance have been identified at the Project site. Project development would not result in the conversion of any Prime Farmlands, Unique Farmlands or Farmlands of Statewide Importance to non-agricultural uses. b) Conflict with Agricultural Zoning There are no areas in the vicinity of the Project site that have been zoned for agricultural uses and no parcels near the Project site are currently under Williamson Act contracts. Project development would not result in the conversion of any land currently zoned for agricultural use or in Williamson Act contracts to non-agricultural uses. c) Non-Agricultural Use Farmland Conversion The Project involves no activities that would result in conversion of farmland or other land in agricultural to non-agricultural uses. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 2rJ Environmental Factors and Focused Questions for Determination of Environmental Impact AIR QUALIN -Where available, the significance criteria established by the applicable air quality management or air pollution control district maybe relied upon to make the following determinations. Would the project: a) Conflict with or obstruct implementation of the applicable air quality plan? b) Violate any air quality standard or contribute substantially to an existing or projected air quality violation? c) Result in a cumulatively considerable net increase of any criteria pollutant for which the project region is non-attainment under an applicable federal or state ambient air quality standard (including releasing emissions, which exceed quantitative thresholds for ozone precursors)? d) Expose sensitive receptors to substantial pollutant concentrations? e) Create objectionable odors affecting a substantial number of people? Potentially Less Than Less Than Significant Significant with Significant No Impact Mitigation Impact Impact /~ /~ /~ /~ /~ a) Conflict with Air Quality Plan Settingz The analysis of the air quality characteristics of South San Francisco, including its climate and meteorological patterns are derived from the City of South San Francisco General Plan prepared in 1997, supplemented by the Bay Area Air Quality Management District (BAAQMD) CEQA Guidelines.' Additional information, such as air quality data for the years 1993 through 1996, and the current status of Bay Area air quality with regard to federal standards, was obtained from the BAAQMD Office of Public Information, and its Education Division.4 Where available, the significance criteria established by the applicable air quality management or air pollution control district may be relied upon to make determinations regarding specific air quality impacts. Bay Area Air Quality Management District, April 1996, BAAQMD CEQA Guidelines: Assessing the Air Quality Impacts of Projects and Plans. Bay Area Air Quality Management District: Summary of Air Pollution in the Bay Area, individual sheets for 1995-1999; and various Press Releases, Office of Public Information, Education Division, August 1997 through January 2001. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 26 Impact The project is not in conflict with nor obstructs implementation of any applicable air quality plan. Therefore, there would be no impact from the project on those plans. b) Air Quality Standards Setting The San Francisco Bay Air Basin is currently designated as an "attainment" area for federal standards for carbon monoxide (CO), sulfur dioxide (S02), nitrogen dioxide (N02), and is designated as "non-attainment-unclassified" for federal ozone and particulate matter (PM-10) standards. Under state standards, the region also has "attainment" status for CO, S02, and N02, but is "non-attainment" for the state PM-10 standard. For fine-particulate matter (PM-2.5) national standards, the Bay Area is also "non-attainment-unclassified.i5 The BAAQMD operates several air quality monitoring stations throughout the Bay Area to measure air quality and to assess progress on meeting the state and federal standards. Impact Threshold of Significance: The BAAQMD considers projects which generate over 550 pounds per day of CO, or 80 pounds per day of reactive organic gases (ROG, which contributes to the formation of ozone), nitrogen oxides (NOx, such as N02), or PM-10 as having significant direct and cumulative air quality impacts (i.e., contributing substantially to the current exceedances of air quality standards for ozone and PM-10). Consistent with CEQA, BAAQMD requires all phases of a project to be evaluated for potential impacts, including impacts associated with construction activity (grading, exhaust from construction equipment, and any required demolition) and with the operation of the completed project (related to vehicle exhaust or stationary sources such as from industrial sources). BAAQMD regards emissions of PM-10 and other pollutants from construction activity to be less than significant if dust and particulate control measures are implemented, instead of requiring quantitative analysis of construction activity to determine significance. ^ IMPACT 1: Generation of Particulate Matter. Construction of the proposed Cell Genesys Development would have short-term air quality effects, primarily due to the generation of particulate matter (PM-10). PM-10 is normally generated by diesel construction vehicles .and equipment, the~isturbance of soils ..through excavation and grading, construction vehicle travel on unpaved surfaces and the tracking of soils onto paved roads. Failure to implement appropriate dust control measures would be a s Bay Area Air Quality Management District, "Bay Area Attainment Status" April 1999 (obtained at BAAQMD website: www.baagmd.gov). INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 27 potentially significant environmental impact, and would be inconsistent with the current Clean Air Plan. ^ MITIGATION MEASURE 1: Dust Control Measures. The BAAQMD's CEQA Guidelines (1999) acknowledges that construction activity emissions vary markedly from project to project, from day to day, and from one contractor to another. Rather than focus on a quantification of project-related emissions, the BAAQMD has developed a menu of mitigation options to control construction activity dust emissions. The BAAQMD (1999) considers implementation of all applicable dust control measures (which vary according to project magnitude) as reducing project- related particulate (PMio) emissions to less-than-significant levels. These measures are grouped into three categories as follows: • "Basic Control Measures" apply to all construction sites. • "Enhanced Control Measures" apply to sites greater than four acres. • "Optional Control Measures" apply to larger sites near sensitive receptors. Based on the project's 6.74-acre size, implementation of the Basic and Enhanced Control Measures listed below would maintain project construction-related impacts at a less than significant level. Construction equipment emits carbon monoxide and ozone precursors during combustion of diesel fuel. The BAAQMD's determination, however, is that these emissions have been included in the emissions inventory, which was the basis for the 1997 Clean Air Plan and subsequent air quality plans. Since the BAAQMD does not consider construction-related exhaust emissions to be "new" emissions, they would not impede attainment or maintenance of ozone or CO standards in the air basin (BAAQMD, 1999). Therefore, temporary increases in exhaust emissions would be considered less than significant. The following measure will be required during project construction to reduce construction emissions to a less than significant level: Construction activities must comply with the "Basic Control Measures" and "Enhanced Control Measures" for dust emissions as outlined in the BAAQMD CEQA Guidelines. These requirements are listed as follows: INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE ZS 1. Basic Control Measures • Water all active construction areas at least twice daily. • Cover all trucks hauling soil, sand, and other loose debris or require all trucks to maintain at least two feet of freeboard. • Pave, apply water three times daily, or apply (non-toxic) soil stabilizers on all unpaved access roads, parking areas, and staging areas at construction sites. • Sweep daily (with water sweepers) all paved access roads, parking areas, and staging areas at construction sites. • Sweep streets daily (with water sweepers) if visible soil material is carried onto adjacent public streets. 2. Enhanced Control Measures • Hydroseed or apply (non-toxic) soil stabilizers to inactive construction areas (previously graded areas inactive for ten days or more). • Enclose, cover, water twice daily or apply (non-toxic) soil binders to exposed stockpiles (dirt, sand, etc.). • Limit traffic speeds on unpaved roads to 15 mph. • Install sandbags or other erosion control measures to prevent silt runoff to public roadways. • Replant vegetation in disturbed areas as quickly as possible. The implementation of Mitigation Measure 1 would reduce the impact of dust from construction of the Project to a level of less than significant with mitigation. c) Cumulative Air Quality Effects Impact Threshold of Signifzcance: The Project's impact would be significant if it would result in a cumulatively considerable net increase of any criteria pollutant for which the project region is non-attainment under an applicable federal or state ambient air quality standard (including releasing emissions that exceed quantitative thresholds for ozone precursors). The proposed 159,949 square-foot office/Research & Development Project would result in a net traffic increase of 193 daily trips, with 100 a.m. peak hour trips and 9b p.m. peak hour trips. Air emissions increases associated with the proposed project would be considered less than significant since the size of the proposed project would not exceed the Bay Area Air INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 29 Quality Management District's (BAAQMD) threshold levels for potential significance. The BAAQMD threshold level for potential significance for office park use is 210,000 square feet or 2,000 vehicle trips per day for any use. Under this project size or traffic volume, a detailed air quality analysis is not required unless warranted by the specific nature of the project or project setting. Based on the project size and project-related traffic increases, an air quality impact assessment would not need to be prepared and submitted to the BAAQMD for review. d) Exposure of Sensitive Receptors to Substantial Pollution Concentrations Setting The BAAQMD defines exposure of sensitive receptors to toxic air contaminants and risk of accidental releases of acutely hazardous materials (AHMs) as potential adverse environmental impacts. Examples of sensitive receptors include schools, hospitals, residential areas with children, and convalescent facilities. Impact Threshold of Significance: The threshold of significance for toxic air contaminants is reached if the probability of contracting cancer for the Maximally Exposed Individual (MEI) exceeds 10 in one million. The presence of AHMs near sensitive receptors may be considered a significant impact if the potential exposure exceeds state guidelines as determined by the Lead Agency in consultation with the City of South San Francisco Health Services Department. The impact may also be cumulative if it contributes to a potential exposure to sensitive receptors. Disturbance of soil contaminated with AHMs as a result of construction may also be significant. Construction-related air quality impacts are highly localized in nature. Thus, a one-block radius is an adequate distance within which to consider potential impacts to sensitive receptors due to construction. The implementation of Mitigation Measure 1 (Dust Control Measures) to minimize disturbance of the on-site soils and generation of dust from the site during construction, combined with any other requirements of a Site Management Plan for controlling airborne dust, would reduce the potential for exposure of sensitive receptors to airborne particles or pollutants during construction activity to a level of less than significant with mitigation. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 3O e) Odors Setting There are currently no odor-generating activities at the Project site. Impact Threshold of Significance: The BAAQMD defines public exposure to offensive odors as a potentially significant impact. Potential odor impacts are based on a list of specific types of facilities, such as wastewater treatment plants, landfills, refineries, etc. There are no existing sources of offensive odors located in the vicinity of the Project site and none would be expected to exist as part of the Project. Therefore, the Project would have no impact related to the creation of odors. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 3'I Environmental Factors and Focused Questions for potentialy Less Than Less Than Determination of Environmental Impact Significant Significant with Sign cant No Impact Mitigation Impact Impact IV. BIOLOGICAL RESOURCES -Would the Project: a) Have a substantial adverse effect, either directly ( ] [ ] [ ] [ /] or through habitat modifications, on any species identified as a candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by the Califomia Department of Fish and Game or U.S. Fish and Wildlife Service? b) Have a substantial adverse effect on any [ ] ( ] ( ] (/] riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations or by the California Department of Fish and Game or US Fish and Wildlife Service? c) Have a substantial adverse effect on federally [ ] [ ] ( ] (/ ] protected wetlands as defined by Section 404 of the Clean Water Act (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means? d) Interfere substantially with the movement of any [ ] [ ] [ ] (/] native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites? e) Conflict with any local policies or ordinances ( ] [ / ] [ ] ( ] protecting biological resources, such as a tree preservation policy or ordinance? f) Conflict with the provisions of an adopted ( ] [ /] [ ] ( ] Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan? Items a) through d) Impact Cell Genesys' facility would be located in a largely industrial area, on a site that has already been developed. The-Project would have-no-impact on-any endangered, threatened or rare species or their habitats, or to any federally protected wetlands or wildlife corridors. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 32 Items e) and f) Setting The Project site is surrounded by various types of landscaping, including low ground covers, assorted shrub types and small to large trees. Figures 8 to 12 display examples of landscaping found around the Project site's perimeter, including some trees that are classified as protected trees under the City of South San Francisco's Tree Preservation Ordinance due to their large circumference measurements. The tree in the foreground of Figure 8, a protected tree, is located on the northeast corner of the Project site. Figure 9 shows a group of trees located along the site's eastern edge, while Figure 10 is a picture of two relatively unhealthy trees located along Forbes Boulevard. Figure 11 shows a tree located at the intersection of Forbes Boulevard and Allerton Avenue. Figure 12 displays a few protected trees that are located at the Project site's northwest corner. Impact Threshold of Significance: The Project would have a significant environmental impact if it were to conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance, Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan. ^ IMPACT 2: Removal of Protected Trees. Construction of the Cell Genesys Development would require cutting down thirty-three (33) trees and several extensively shrubbed areas located on the Project site. Eight (8) of the trees on the site are considered protected trees under Section 13.30.020(f)(1) of the City of South San Francisco Municipal Code relating to tree preservation (Tree Ordinance). According to the Ordinance, a protected tree is defined as the following: 1. Any tree with a circumference of 48 inches or more when measured 54 inches above natural grade; or 2. A tree or stand of trees so designated by the Director based upon findings that it is unique and of importance to the public due to its unusual appearance, location, historical significance or other factor; or 3. A stand of trees in -which the Director-has determined-each tree independent upon the others for survival. The eight protected trees on the site are considered protected because their trunk circumferences measure more than 48 inches above natural grade. Cutting down these trees would be a potentially significant impact of the Project. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 33 • MITIGATION MEASURE 2: Tree Replacement. According to the Tree Ordinance, no protected tree shall be removed, pruned, or otherwise materially altered without a permit except as provided in Section 13.30.030. A tree cutting permit requires replacement of a tree with three 24-inch box or two 36-inch box minimum size landscape trees for each tree removed, as described in Section 13.30.080 of the Tree Ordinance. Adherence to the provisions of the City of South San Francisco Tree Ordinance would reduce the impact of cutting down eight protected trees on the Project site to a level of less than significant with mitigation. Figure 8 Vegetation on Northeast Corner of Project Site ~_ --~ ~~,<~= ~.; .: ~;. .`~~Y~.. ~. -. fJ+.-.. ~~-i =" ._...~ INITIAL STUDY /MITIGATED NEGATIVE DECLAR,4TION CELL GENESYS DEVELOPMENT PAGE 34 Figure 11 Vegetation at Forbes/Allerton Intersection Figure 12 Vegetation at Northwest Corner of Project Site '~ ~ -~- ,-~ ,i INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENE$YS DEVELOPMENT PAGE 36 Figure 9 Vegetation on Eastern Edge of Project Site Figure 10 ~+-. „ ~k Vegetation Along Forbes Boulevard INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 35 ~..~ _. .;# ' ,.~ Y ---. ~. _ Environmental Factors and Focused Duestions for Potentially Less Than Less Than Determination of Environmental Impact Significant Significant with Significant No Impact Mitigation Impact Impact V. CULTURAL RESOURCES -Would the Project: a) Cause a substantial adverse change in the [ ] [ ] [ / ] [ ] significance of a historical resource as defined in §15064.5? b) Cause a substantial adverse change in the [ ] [ /] [ ] [ ] significance of an archaeological resource pursuant to §15064.5? c) Directly or indirectly destroy a unique [ ] [ ] [ ] [ / ] paleontological resource or site or unique geologic feature? d) Disturb any human remains, including those [ ] [ ] [ ] [ / ] interred outside of formal cemeteries? a) Historical Resources Impact Threshold of Significance: The Project would have a significant environmental impact if it were to cause a substantial adverse change in the significance of a historical resource as defined in § 15064.5. The project would not cause a substantial adverse change in the significance of a historical resource as defined in ~ 15064.5, since the existing building shell on site has no historical value. The project would have a no impact. b) Archaeological Resources Impact Threshold of Significance: The Project would have a significant environmental impact if it were to cause a substantial adverse change in the significance of an archaeological .resource as defined in ~ 15064.5. ^ IMPACT 3: Potential Disturbance of Archaeological Resources. The Project site is a previously disturbed, developed site where no known archaeological sites are located. However, given that archaeological remains have been found in the Project's vicinity, the presence of archaeological remains underneath the Project site cannot be discounted. The Project could have a significant impact on any archaeological remains discovered at the Project site. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 37 ^ MITIGATION MEASURE 3: Monitoring of Grading Process. A certified archaeologist shall be present at the Project site during the initial grading process to monitor grading activities and ensure the protection and preservation of any archaeological resources discovered at the Project site. This would reduce the impact of the Project on archaeological resources to a level of less than significant with mitigation. c) Paleontological Resources/Unique Geologic Features Impact Threshold of Significance: The Project would have a significant environmental impact if it were to directly or indirectly destroy a unique paleontological resource or site or unique geologic feature. No unique paleontological or geologic features have been nor are expected to be identified at the Project site. Therefore, the Project would be expected to have no impact on paleontological resources and unique geologic features. d) Disturbance of Human Remains Impact Threshold of Significance: The Project would have a significant environmental impact if it were to result in the disturbance of any human remains. No human remains have been identified at the Project site. However, if such remains are encountered during site preparation associated with the construction of the Cell Genesys Development, all work shall be halted in the vicinity, and the San Mateo County Coroner shall be informed to determine if an investigation of the cause of death is required, and to determine if the remains are of Native American origin. If such remains are of Native American origin, the nearest tribal relatives as determined by the state Native American Heritage Commission shall be contacted to obtain recommendations for treating or removal of such remains, including grave goods, with appropriate dignity, as required under Public Resources Code Section 5097.98. This would reduce the potential impact associated with the discovery of human remains at the Project site to a level of less than significant. It is expected that there would be no impact from the Project related to the disturbance of human remains. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 3S Environmental Factors and Focused Questions for Potentially Less Than Less Than Determination of Environmental Impact Significant Sign cant with Significant No Impact Mkiaation Impact Impact VI. GEOLOGY AND SOILS -Would the Project: a) Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving: i) 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? Refer to Division of Mines and Geology Special Publication 42. ii) Strong seismic ground shaking? [ ] [ /] ( ] ( ] iii) Seismic-related ground failure, including [ ] [ ] ( ] (/] liquefaction? iv) Landslides? ( ] ( ] (/ ] ( ] b) Result in substantial soil erosion or the loss of [ ] [ ] ( ] (/ ] topsoil? c) Be located on a geologic unit or soil that is ( ] [ ] (/ ] [ ] unstable, or that would become unstable as a result of the Project, and potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction or collapse? d) Be located on expansive soil, as defined in ( ] [ ] (/] ( ] Table 18-1-B of the Uniform Building Code (1994), creating substantial risks to life or property? e) Have soils incapable of adequately supporting [ ] ( ] ( ] (/ ] the use of septic tanks or alternative waste water disposal systems where sewers are not available for the disposal of waste water? Setting6 The relative stability and composition of different types of soils can contribute to hazard risks by amplifying earthquake waves, increasing susceptibility to liquefaction and landslides, and affecting flood levels. South San Francisco occupies three general topographic zones: the lowland zone, the upland zone and the hillside zone.' The Project site is located within the Upland Zone, at an altitude of about 125 feet mean sea level. b Most of the information in this section is derived from: Treadwell & Rollo, Geotechnicallnvestigation: Cell Generys, Inc. Corporate Headquarters fr Research Center, S00 Forbes Avenue, August 8, 2001. Dyett & Bhatia, South San Francisco General Plan: Existing Conditions and Planning Issues, 1997. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 8J EPLAN.DWG (D CD 7 n CD D r -1 D D C7 to \. o W . .. _~ __ _ 3 o N ~~ J ~ ~ / ~~ ,,~ ca d - ~ \ / _~ 8 ~~~ /~F J \ / ~ ~e `~~ ~t_ • ~ ~ O ~ N m v ~ ~~ ~ ;, c ._.~ + r ~ ~ __., •. 1. .J VI T~ ~ I N W ~ W O 0 C r r~ < ~ D ~ ~ .,.~.~ m ~„ r~ T ~" s No > o N • ~ ~> '~ 1 -• F m x -1 Z G1 C r v z L7 z 0 m ~ O O _x w m ~ o. ~ ~~ w ~ ~ o m N _. ~~ ~ -~ w ~ ~ ~ m ~ ~ ~. o m m ~~~"~ CD ~ Q N p O N ~ ~ ~ • < w ~ ~ . ~, o 0 O X ~ ~~ v . -P cn7 ~ D- ~ C ~ a' v - - - -77.09_ - - ~- ~ I-: 1 . v 1° J o i v m I W . ~ s a W -i D ~ -~ D m a ~ ~ ~ ~~ ~ O O- O x _ C O- O x o ' ~ ~ . o N c ° Z N~~ ~~ o D O 000 0o Z -°ow on~i ~ ~ o' a~~ ~ o' ~~ o Tv - o ~ Q ~ ~ C O ~1 O 1 N `~ (Q (Q O O ~ ,Q' 0 0 Subsurface Conditions. Approximately 1.5 to 5.0 feet of fill blankets the site around the perimeter of the existing building. the fill is primarily aggregate base material and sand placed for the pavement section or utility trench backfill. Residual soil and bedrock underlie the fill. Residual soil consists of very stiff to hard sandy clay and was encountered in borings B-1, B-6, B-7, B-8, B-10, SB-1, SB-2, SB-5, SB-6 and SB-8. Atterberg limits test results indicate the residual soil is moderately expansive, undergoing volume changes with changes in moisture content. Bedrock consisting of weathered shale and sandstone of the Franciscan Complex was encountered beneath the fill and residual soil in each of the borings to the maximum depths explored. The bedrock is generally gray to black, depending on the extent of weathering. The weathering and decomposition of the rock vary greatly, and the bedrock ranges from friable to moderately hard, with the moderately hard rock generally occurring as sandstone inclusions in a softer shale matrix. Groundwater was encountered only in boring B-7 at a depth of 27 feet at the time of drilling. Groundwater beneath the site is likely confined to fractures and pervious zones within the bedrock. The boring was immediately backfilled after completion. It should be noted that this may not be the stabilized groundwater level. a)(i) Exposure of People or Structures to Known Earthquake Fault Setting The major active faults in the area are the San Andreas and Hayward Faults, at distances of about five and 28 kilometers from the site respectively. In 1868 an earthquake with an estimated Moment magnitude of 7.0 on the Richter scale occurred on the southern segment of the Hayward Fault between San Leandro and Fremont. Since 1800, four major earthquakes have been recorded on the San Andreas Fault with Moment magnitudes ranging from 6.25 to 7.9. in 1999, the Working Group on California Earthquake Probabilities at the United States Geologic Survey predicted a 70 percent probability of a magnitude 6.7 or greater earthquake occurring in the San Francisco Bay Area by 2030. Impact Threshold of Signifzcance: The Project would have a sign cant environmental impact if it were to expose people or structures to potential substantial adverse effects associated with the rupture of a known earthquake fault. The Project site is not within an Earthquake Fault Zone, as defined by the Alquist-Priolo Earthquake Fault Zoning Act, and no known active or potentially active faults exist on the site. Therefore, the risk of surface faulting is considered to be less than significant. INITIAL STUDY /MITIGATED NEGATNE DECLARATION CELL GENESYS DEVELOPMENT PAGE ~ a)(ii) Exposure of People or Structures to Strong Seismic Shaking Impact Threshold of Significance: The Project would have a significant environmental impact if it were to expose people or structures to potential substantial adverse effects associated with strong seismic ground shaking. ^ IMPACT 4: Adverse Effects of Seismic Related Ground Shaking. The .proposed Cell Genesys Development would be occupied by Cell Genesys staff, who could be exposed to adverse effects related to seismic ground shaking. This would be a potentially significant impact of the Project. ^ MITIGATION MEASURE 4: Adherence to Geotechnical Engineering Recommendations. Treadwell and Rollo judge the soil and bedrock conditions at the Project site to be suitable from a geotechnical standpoint for the proposed construction, provided that their recommendations are incorporated into the Project plans and implemented during construction. Their recommendations are the following: Site Preparation and Grading. Grading operations should commence after demolition and removal of the existing building, pavements, floor slabs and underground utilities within the development area. Following demolition, all areas to receive improvements should be stripped of vegetation and organic topsoil. The pavement material, including asphalt, may be segregated from organic topsoil and used as compacted fill, provided it meets the fill requirements presented in a subsequent section of this report and is acceptable from an environmental standpoint. The stripped organic soil can be stockpiled for later use in landscaped areas, if approved by the architect. Organic topsoil should not be used as compacted fill. The surface exposed by stripping should be scarified to a depth of at least six inches, moisture-conditioned to above the optimum moisture content and compacted to at least 90 percent relative compaction.'Z If soft or loose soil is encountered, the unsuitable material should be overexcavated and replaced with suitable fill material and similarly compacted and moisture conditioned. The exposed ground surface should be kept moist during subgrade preparation. 'Z Relative compaction refers to the in-place dry density of soil expressed as a percentage of the maximum dry density of the same material, as determined by the ASTM D1557-91 laboratory compaction procedure. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 45 Select fill should consist of on-site or imported soil that is non-corrosive, free of organic matter, contains no rocks or lumps larger than three inches in greatest dimension, has a liquid limit less than 40 and plasticity index less than 12, and is approved by the geotechnical engineer. In addition, the select fill should contain between 10 and 25 percent fines (particles passing the No. 200 sieve) to reduce potential for surface water infiltration. It is likely the surface sand and gravel fill will meet the select fill criteria. Based on the plasticity and liquid limit criteria, the near- surface residual soil is not expected to meet the criteria for select fill. A sample of the on-site and import material to be used as select fill should be submitted to the geotechnical engineer for testing at least three business days prior to use at the site. Fill should be placed in horizontal layers not exceeding eight inches in loose thickness, moisture-conditioned to above the optimum moisture content, and compacted as presented in Table 1. TABLE 1 COMPACTION REQUIREMENTS LOCATION REQUIRED COMPACTION (PERCENT); MOISTURE REQUIREMENT Building pad -select fill 95+ Above optimum General fill -native soil backflll 90 - 93 3% above optimum General fill -select fill 90 + Above optimum Utility trench -native soil backflll 90 - 93 3% above optimum Utility trench -select fill 90 + Above optimum Utility trench -clean sand or gravel 95 + Above optimum AC pavement subgrade -native soil 95 Above optimum AC pavement subgrade -select fill 95+ Above optimum AC pavement -aggregate base 95+ Above optimum Concrete paving Same as AC pavement Same as AC pavement Concrete Flatwork -native soil 90 - 93 3% above optimum Concrete Flatwork -select fill/AB 90+ Above optimum Utility Trenches. Excavations for utility trenches can generally be made with a backhoe. Despite careful site preparation, obstructions and hard rock may be encountered rendering some of the trenching operations difficult. All trenches should conform to the current CAL-OSHA requirements. Backfill for utility trenches and other excavations is also considered fill, and should be compacted according to the recommendations presented in Table 1. Special care INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 46 should be taken when backfilling utility trenches in pavement areas. Poor compaction may cause excessive settlements, resulting in damage to the pavement section. When necessary, trench excavations should be shored and braced to prevent cave-ins in accordance with all safety regulations. Where sheet piling is used as shoring, and is to be removed after backfilling, it should be placed a minimum of two feet away from the pipes or conduits to prevent disturbance to them as the sheet piles are extracted. Where trenches extend below the groundwater level, it will be necessary to temporarily dewater them to allow for placement of the pipe and/or conduits, and backfill. To provide uniform support, pipes or conduits should be bedded on a minimum of four inches of sand or fine gravel. After the pipes and conduits are tested, inspected (if required) and approved, they should be covered to a depth of six inches with sand or fine gravel, which should be mechanically tamped. Building Foundations. Provided that settlement of up to 1/z inch is acceptable, the building may be supported on conventional spread footings bearing on native residual soil (sandy clay) or the shale and sandstone bedrock. Individual spread footings should be at least 36 inches square and continuous footings should be at least 24 inches wide and bottomed in the residual soil or bedrock. All footings should be founded a minimum of 24 inches below the lowest adjacent soil subgrade and 12 inches into residual soil or bedrock. The footings may be designed for allowable bearing pressures of 6,000 pounds per square foot (psf) for dead plus live loads and 8,000 psf for total design loads, including wind or seismic forces. Lateral loads can be resisted by a combination of passive pressure on the vertical faces of the footings and friction along the bases of the footings. Passive resistance may be calculated using a rectangular distribution of 1,500 psf; the upper one-foot of soil should be ignored unless it is confined by slabs or pavement. Frictional resistance should be computed using a base friction coefficient of 0.35. If a waterproofing system is used beneath the footings, the frictional resistance should be reduced to a value of 0.2. These values include a factor of safety of at least 1.5. The footing excavations should be free of standing water, debris, and disturbed materials prior to placing concrete. We should check the excavations prior to placement of reinforcing steel to confirm the exposed residual soil or bedrock is suitable to support the design bearing pressure encountered in the excavations, it should backfilled with lean or structural concrete. . If loose soil or undesirable material is be removed and the overexcavation INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 47 Concrete Slab-On-Grade. The slab-on-grade floor should be supported on at least 12 inches of select fill placed as described above in the Site Preparation and Grading section. As a minimum, a moisture barrier should be installed beneath the slab-on-grade floor. The moisture barrier may be included as part of the select fill thickness. Atypical moisture prevention barrier includes a capillary moisture break consisting of at least a six-inch-thick layer of clean, free-draining gravel or crushed rock (1/2 to 3/a-inch gradation) overlain by a moisture-proof membrane at least 10 millimeters thick. The membrane should be covered with two inches of sand for protection against puncturing or tearing during construction and to aid in curing the concrete slab. If the previously compacted soil subgrade is disturbed during footing and utility excavation, the subgrade should be re-compacted to provide a firm, unyielding surface prior to placement of the capillary break material. The crushed rock and sand layers should conform to the gradation requirements presented in Table 2. TABLE 2 GRADATION REQUIREMENTS FOR CAPILLARY BREAK AND SAND SIEVE SIZE PERCENTAGE PASSING SIEVE GRAVEL OR CRUSHED ROCK 1 inch 100 314 inch 30-75 1l2inch 5-10 3/flinch 0-2 SAND No. 4 100 No. 200 0-5 If water vapor moving through the slab is considered detrimental, in lieu of the moisture barrier, a waterproofing membrane should be installed. The membrane should consist of apre-applied, self-adhering high-density polyethylene (HDPE). Seismic Design. The buildings would be designed using the 1997 Uniform Building Code (UBC). - For design in accordance with the 1997 UBC, Treadwell & Rollo recommend the following: • Seismic Zone Factor 4 • Soil profile Type Sa • Near Source Factors Na and N~ of 1.14 and 1.48, respectively. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 48 Flexible Pavement Design. The State of California flexible pavement design method was used to develop the recommended asphalt concrete pavement sections. The geotechnical engineers expect the final soil subgrade in asphalt-paved areas would generally consist of residual soil comprised of sandy clay. On the basis of laboratory test results of this soil, Treadwell & Rollo selected an R-value of 20 for design. If the existing subgrade would be raised in the paved areas, the fill material should have an equivalent or higher R-value than the native soil. Additional R-value tests should be performed on any proposed fill to verify its R-value. The pavement design may need to be revised if material with an adequate R-value cannot be found. Treadwell & Rollo presented design alternatives for three traffic indices (TI), 5.0, 5.5, and 6.0. For comparison, a TI of 5.0 assumes passenger car traffic with occasional trucks. Selection of the appropriate TI for design should be confirmed by the project civil engineer. If additional traffic indexes (TIs) are required for the project, the geotechnical engineers could assist the design team with the associated pavement recommendations. Table 3 presents flexible pavement section recommendations for the three TI values. TABLE 3 PAVEMENT SECTION DESIGN TRAFFIC INDEX ASPHALTIC CONCRETE INCHES CLASS 2 AGGREGATE. BASE R = 78 INCITES 5.0 2.5 8.5 5.5 3.0 9.0 6.0 3.0 10.5 Pavement components should conform to the current Caltrans Standard Specifications. The upper six inches of the soil subgrade in pavement areas should be moisture-conditioned to above optimum moisture content and compacted to at least 95 percent relative compaction where either native soil or imported fill is exposed at subgrade level. Aggregate base should be compacted to at least 95 percent relative compaction. To prevent irrigation water from entering the pavement section, vertical curbs adjacent to landscaped areas should extend at least three inches into the underlying clay. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 49 Corrosivity Evaluation. Based on the resistivity measurements, 1,000 to 1,400 ohms- cm, the soil samples tested are classified as "corrosive". All buried iron, steel, cast iron, ductile iron, galvanized steel and dielectric coated steel or iron placed at the site should be properly protected against corrosion depending upon the critical nature of the structures. In addition, all buried metallic pressure piping such as ductile iron firewater pipelines should be protected against corrosion. Both the chloride and sulfate ion concentrations, with ranges of none detected to 31 milligrams per kilogram (mg/kg) and 120 to 190 mg/kg, respectively, were determined to be insufficient to attack steel embedded in a concrete mortar coating. The hydrogen ion activity (pH) of the soil samples tested is not corrosive to buried iron, steel, mortar-coated steel and reinforced concrete structures. The redox potential of the soil samples tested indicates potentially "slightly corrosive" soils resulting from anaerobic soil conditions. Treadwell & Rollo should review the final foundation plans and specifications to check that they are in general conformance with the intent of their recommendations. They should observe fill placement and compaction, and perform field density test to check that adequate fill compaction has been achieved. During construction, the geotechnical engineers should observe the installation of the foundation system. Footing excavations should be checked to verify the foundation soil and rock are as anticipated. These observations would allow comparison of actual and anticipated soil conditions, check that the contractor's work conforms to the geotechnical aspects of the plans and specifications, and ensure that the building would perform as planned. These mitigation measures would reduce the impact of seismic ground shaking to people who would occupy the Cell Genesys Development to a level of less than significant with mitigation. a)(iii) Seismic-Related Ground Failure, Including Liquefaction Impact Threshold of Significance: The Project would have a significant environmental impact if it were to expose people or structures to potential substantial adverse effects associated with seismic- related ground failure, including liquefaction. Soil liquefaction is typically caused by strong vibratory motion due to earthquakes. Research and historical data indicate that soil liquefaction occurs in saturated, loose granular soil (primarily fine to medium grained clean sand deposits) during or after strong seismic ground INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 5O shaking. Liquefaction is typified by a near total loss of shear strength in the affected soil layer, thereby causing the soil to flow as a liquid. The potential hazards associated with soil liquefaction below or near a structure are loss of foundation support, lateral spreading, sand boils and areal and differential settlements. Saturated, cohesionless soil can liquefy as it experiences a temporary loss of shear strength due to a transient rise in excess pore pressure generated by strong ground motion. Treadwell & Rollo found clean sand at random locations around the site (B-2, B-7, B-10, SB-3, SB-5, SB-6 and SB-8). These deposits were judged to be localized fill deposits placed during initial site grading. In addition, the groundwater level is below this material. Therefore, there would be no impact related to liquefaction induced settlement and lateral spreading at the Project site. a)(iv) Exposure of People or Structures to Landslides Impact Threshold of Significance: The Project would have a significant environmental impact if it were located on a geologic unit or soil that is unstable, or that would become unstable as a result of the Project, and potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction or collapse. The Project site is located on land that is relatively flat, but that is sloped slightly near its northwestern corner. The risk of landsliding on the Project site is considered less than signi fzcant. There is a hill located off site along the site's eastern side. Treadwell & Rollo did not study the hill's landslide potential since it was not within the scope of their analysis. However, according to Treadwell & Rollo, the hill appears to be stable. b) Substantial Soil Erosion or Loss of Topsoil Impact Threshold of Significance: The Project would result in a significant environmental impact if it were to result in substantial soil erosion or in the loss of topsoil. Site soils are covered with either asphalt paving or concrete and have no exposure to water or wind erosion forces, though temporary erosion may occur during construction. However, standard erosion control measures can be employed to reduce this erosion to negligible levels during construction. Local jurisdictional rules governing erosion protection should be followed during construction in order to ensure no impact from the Project. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 5'I c) Unstable Geological Conditions Impact Threshold of Significance: The Project would have a significant environmental impact if located on a geologic unit or soil that is unstable, or that would become unstable as a result of the Project, and potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction or collapse. Strong ground shaking can cause unsaturated sand above the groundwater table to densify and settle. Treadwell & Rollo believes that only portions of streets, parking lots and sidewalks, which rest on loose sands could have earthquake induced settlements, and that these could be on the order of one inch. The residual soil, consisting of sandy clay, and the weathered shale and sandstone bedrock that are present beneath the proposed building location are capable of supporting moderate foundation loads. Shallow, spread type footings may be used. Properly installed footings gaining support in residual soil and bedrock should experience settlement of less that 0.5 inches.g This would be a less than significant impact of the Project. The potential for subsidence to occur at the site is considered to be low, as the site has not been subject to fluid withdrawal. d) Expansive Soils Impact Threshold of Significance: The Project would have a significant environmental impact if located on expansive soil, creating substantial risks to life or property. The Project site is subject to expansive surface soil due to volume changes during seasonal fluctuations in moisture content. These volume changes can cause foundation and floor slab cracking. Therefore, foundations and slabs should be designed and constructed to resist the effects of moderately expansive residual soil. The nature of design and construction at the Project site is discussed in more detail above in section a) ii). Adherence to recommended design and construction techniques would reduce the impact of expansive soils to a level of less than significant. a Treadwell & Rollo, Geotechnical Investigation: Cell Generys, Inc. Corporate Headquarters ~ Research Center, p.10, August 8, 2001. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 5Z Setting Colma Creek, the City's main natural drainage system, is a perennial stream with a water shed of about 16.3 square miles that trends in a roughly southeasterly direction through the center of the City. The Colma Creek watershed is one of the three largest in the County. The basin is bounded on the northeast by San Bruno Mountain and on the west by a ridge traced by Skyline Boulevard. Dominant topographic features of the drainage basin include two relatively straight mountain ridges that diverge toward the southeast that are connected by a low ridge at the northern boundary of the area. The valley enclosed by the ridges widens toward the southeast where it drains into San Francisco Bay. a) Violation of Water Quality Standards or Waste Discharge Requirements Impact Threshold of Significance: The Project would have a significant environmental impact if it were to result in any violation of existing water quality standards or waste discharge requirements. The Project would not violate any water quality standards or waste discharge requirements, thereby presenting no impact. b) Deplete or Interfere Substantially with Groundwater Impact Threshold of Significance: The Project would have a significant environmental impact if it substantially depletes 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. The proposed Project would be located in an urban area and would receive its water supply from existing local infrastructure, thereby not depleting the local groundwater supply. The proposed building structure would be an impervious surface over the land that would to some degree impede recharging of local groundwater. However, since groundwater resources are not used in this area, this impact would be less than significant. c) Alter Existing Drainage Patterns/Erosion and Siltation Effects Impact Threshold of Significance: The Project would have a significant environmental impact if it were to substantially alter the existing drainage pattern of the site in a manner which would result in substantial erosion or siltation. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE ~J9 The Cell Genesys Development would be built on an already developed site in an urban area. There would be no impact related to altered drainage patterns or siltation at the Project site. d) Alter Existing Drainage Patterns/Flooding Effects Impact Threshold of Significance: The Project would have a significant environmental impact if it were to substantially alter the existing drainage pattern of the site or area or substantially increase the rate or amount of surface runoff in a manner that would result in flooding on- or off-site. It is not expected that the proposed Project would alter the existing drainage pattern of the site, nor would it increase the amount of surface runoff, since the site is currently developed with impervious surfaces. Because the Cell Genesys Development would not be built on an undeveloped, pervious surface there would be no impact related to increased surface runoff. e) Runoff Exceeding Drainage System Capacity/Increase Polluted Runoff Impact Threshold of Significance: The Project would have a significant environmental impact if it were to create or contribute runoff water which would exceed the capacity of existing or planned storm water drainage systems or provide substantial additional sources of polluted runoff. ^ IMPACT 7: Increased Erosion During Construction. The soils at the Project site may be susceptible to erosion during construction activities when soils are disturbed. This represents a potentially signifzcant impact associated with the proposed Project. ^ MITIGATION MEASURE 7: Erosion Control Measures. The applicant shall submit a Storm Water Pollution Prevention Plan (SWPPP) and an Erosion Control Plan to the City Engineer prior to the commencement of any grading or construction of the proposed Project. The SWPPP shall include storm water pollution control devices and filters to be installed to prevent pollutants from entering the City's storm drain system and San Francisco Bay. The Plan shall be subject to review and approval of the City Engineer and the City's Storm Water Coordinator. The Project applicant shall be responsible for ensuring that all contractors are aware of all storm water quality measures, and for the implementation of such measures. Failure to comply with the approved construction Best Management Practices (BMPs) will result in the issuance of correction notices, citations or a project stop order. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE GO Plans for the Project shall include erosion control measures to prevent soil, dirt and debris from entering the storm drain system, in accordance with the regulations outlined in the Association of Bay Area Governments Erosion and Sediment Control Handbook. Implementation of the above mitigation measures would reduce the Project's impact to a level of less than significant with mitigation. f) Otherwise Degrade Water Quality Impact Threshold of Significance: The Project would have a significant environmental impact if it were to degrade water quality. The proposed Cell Genesys Development would not increase the amount of impervious surface area on the Project site, since the site is already developed. Therefore, there would be no impact on water quality from point source water pollution at the Project site. g) Place Housing Within A 100-Year Flood Hazard Area Impact Threshold of Significance: The Project would have a significant environmental impact if it were to place any housing units within a designated 100-year flood hazard area. No impact would occur from placing housing within a 100-year flood hazard area, since the Project does not entail the construction of any housing units. h) Place Structures Which Would Impede or Redirect Flood Flows Impact Threshold of Significance: The Project would have a significant environmental impact if it placed any structures in a manner, which would impede or redirect flood flows. The Project site is not located in a 100-year_flood hazard zone12 _and therefore would have no impact related to the placement of a structure in such a way that it would impede or redirect flood flows. 1z Brady and Associates, East of 101 Area Plan, adopted July 1994, p.106. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE G1 i) Expose People or Structures to Flooding Hazards Impact Threshold of Significance: The Project would have a significant environmental impact if it were to result in the exposure of people or structures to flooding hazards. Development of the Cell Genesys Development at the Project site would not expose any people or structures to flooding hazards and therefore would have no impact. j) Inundation by Seiche, Tsunami or Mudflow Impact Threshold of Significance: The Project would have a significant environmental impact if it were to result in the exposure of people or structures to hazards from Seiche, tsunami or mudflow. Development of the Cell Genesys Development at the Project site would not expose any people or structures to hazards from Seiche, tsunami or mudflow and therefore would have no impact. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 62 Environmental Factors and Focused I]uestions for Potentialy Less Than Less Than Determination of Environmental Impact Significant Significant with Sign cant No Impact Mitigation Impact Impact IX. LAND USE AND PLANNING -Would the Project: a) Physically divide an established community? b) Conflict with any applicable land use plan, policy, or regulation of an agency with jurisdiction over the Project (including, but not limited to the general plan, specific plan, local coastal program, or zoning ordinance) adopted for the purpose of avoiding or mitigating an environmental effect? /~ /~ c) Conflict with any applicable habitat conservation ~ ~ (~/ plan or natural community conservation plan? Setting13 South San Francisco has a distinctive land use pattern that reflects the decision to initially locate industrial areas east of supporting homes and businesses in order to take advantage of topography and winds on Point San Bruno. Another development trend that shaped the arrangement of uses was the extensive residential development that occurred during the 1940s and 1950s, creating large areas almost entirely developed with single-family housing. As a result, South San Francisco is largely comprised of single-use areas, with industry in the eastern and southeastern portions of the City, single family homes to the north and west, commercial uses along a few transportation corridors, and multiple family housing clustered in those same corridors. and on hillsides. During the 1950s, the City of South San Francisco converted previously unused marshlands into areas usable for industrial development, drastically reshaping the shoreline and attracting light industry to the City for the first time. Plans were announced in 1963 fora 600-acre industrial park adjacent to the newly developed Oyster Point Marina. This industrial park was South San Francisco's first industrial development to incorporate comprehensive planning, integrated design and performance provisions, and featured a 0.5 Floor Area Ratio. It supplied ample parking and consistent landscaping and building design. In some ways a microcosm of American industry, South San Francisco has been making a slow industrial transformation for the past 30 years. Steel production and other heavy industries have largely been replaced by warehousing, research, development and biotechnology. Because the City's industrial base has continued to evolve as the context for " City of South San Francisco, South San Francisco Genera! Plan, 1999. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 63 industry has changed, industry will continue to play and important role in South San Francisco's future. The City's continued status as a goods transportation hub, stemming mainly from proximity to San Francisco International Airport, is reflected in the presence of large tracts of land, formerly used for heavy industry, east of US 101. As high technology businesses have moved into many of these older industrial areas, conflicts, such as between automobile and truck traffic, and land use and visual character have become increasingly pronounced. The needs of business centers include, smaller blocks, more through street connections, ancillary facilities such as restaurants, easier connections to transit, sidewalks and bikeways and higher landscape standards. These needs are much different than those of warehousing and industrial areas. The City attempts to balance regional growth objectives with conservation of residential and industrial neighborhoods. The East of 101 Area Plan, adopted in 1994, was prepared to maximize the potential of undeveloped or underused properties in the City's traditional industrial east of U.S. 101. Upgrading of existing uses and provisions for quality design are important components of the Plan. In addition to policies relating to land use dispersion, intensities, and transportation, the Plan includes a Design Element to help achieve high standard development. a) Dividing an Established Community The proposed Project would have no impact related to the division of an established community. b) Conflict with Land Use Plan The Project site is currently zoned Planned Industrial (P-1) and is part of the "East of 101" Planning Sub-Area as defined by the City of South San Francisco General Plan. The site's General Plan designation is Business and Technology Park. This designation accommodates campus-like environments for corporate headquarters, research and development facilities, and offices. All development is subject to high design and landscape standards.14 The proposed Project is consistent with the following General Plan policies: Policy 3.5-G-3 Promote campus style biotechnology, high technology and research and development uses. Policy 3.5-I-3 Do not permit any residential uses in the East of 101 area. " Ibid , p.43. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 64 Policy 3.5-I-11 Do not permit any new warehousing and distribution north of East Grand Avenue or in areas designated Business Commercial. The proposed Project is consistent with the following East of 101 Area Plan policies: Policy DE-13 New construction projects shall be required to supply and install street trees and landscaping to meet the City's specifications for their frontages. Streetscape planting, irrigation and hardscape should be designed for minimum maintenance by City staff. Selection and spacing of street trees shall be approved by the City Landscape Architect and the Director of Parks, Recreation and Community Services. Medians should be cobbled and grouted or landscaped with low maintenance plants with automatic irrigation. Policy DE-15 Site design should de-emphasize the visual prominence of parking areas by separating parking areas into relatively small components and locating parking behind buildings whenever possible. The standard practice of placing the majority of the parking between the building and the main street frontage should be avoided when possible. Policy DE-22 Developments in the Planned Industrial categories should include on-site open space as a unifying element and as areas for employee use. Policy DE-25 The design of front yard landscaped buffers should be integrated with that of adjacent sites. Policy DE-27 Parking lots should be shaded with trees and should also include shrubs in most cases. Trees should be planted along parking lot edges and in planters among stalls. Design policies for the number of trees and amount in shrubbery in parking lots are contained in Section D of the Design Element for the individual land use categories. Policy DE-28 Plant species chosen for the area should include low maintenance plants and plants adaptive to the extremes of climate in the area. In addition, plant species and planting design should complement the development's design. Policy DE-29 Lighting on the exteriors of buildings should be incorporated into the overall building and landscape design. Security and entry lights should align with, be centered on, or otherwise coordinate with the building elements. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 65 Policy DE-34 All activities and stored materials in loading, service, storage and trash disposal areas should be screened from views from public streets, trails, adjacent properties, and overhead views from adjacent properties, by planting, berms and/or decorative walls. The screening should be integrated into the design of structures or the site landscaping, so it does not appear as an appendage added to the outside of the structure. This policy applies to all types of outdoor storage areas containing materials, supplies, or equipment, including autos, trucks and trailers. Policy DE-37 The installation or replacement of exposed chain link fences, barbed wire, razor wire or similar material shall not be allowed in those parts of the East of 101 Area that are visible from public rights-of-way, including roads and trails. Policy DE-38 The form and location of structures, the use of building colors and materials and the selection of landscape materials and street furniture shall consider the overall context of the Project and promote the development of a sense of identity for the East of 101 area. Policy DE-43 Retail, flex and industrial buildings should not exceed 35 feet in height. Landmark design elements should not exceed 50 feet in height. Office buildings are not subject to a height limit other than that of the ALUC, as outlined in Policy LU-23. Additional restrictions on building height in the Coastal Commercial category are included in Section D of the Design Element. Exceptions to this policy may be made if warranted by a specific proposed use, or if taller building heights are included in an approved Master Plan. Policy DE-52 Rooftop mechanical equipment should be screened from view by integral architectural elements such as pitched roofs, ornamental parapets, mansards or low towers. Policy DE-56 The following additional design policies apply in Planned Industrial areas: Street Trees: Street trees should be planted within at least 30 feet of each other and should be selected to match or complement the existing pines on Allerton Avenue and portions of East Grand Avenue. Landscape Buffer: Landscape buffers along major arterial streets should be at least 20 feet wide and along other streets at least 10 feet wide. On side and rear property lines, they should be six feet wide. All landscaping shall provide a clear connection between the street and buildings for pedestrians. Blank Walls: Blank building walls should be no more than 30 feet long. Longer lengths of wall should conform with Policy DE-39. Pedestrian scale is of particular importance for campus-like developments and settings. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 66 Building Orientation: Buildings should be oriented with a clear relationship to the street to create a sense of continuity along it. Inviting pedestrian linkages from individual buildings shall be provided. Design Guidelines: New development plans for larger campus-like projects should include specific design guidelines, developed as an integral part of master planning efforts. Parking Lot Shrubs: Medians and bulbs inside the perimeters of a parking lot shall be planted. A minimum of five percent of the total parking lot area required to be landscaped shall be planted with shrubs. Therefore, the proposed Cell Genesys Development would be consistent with and would not conflict with the above applicable City of South San Francisco General Plan land use policies, thereby constituting no adverse impact. ^ IMPACT 8: Inconsistency with East of 101 Area Plan. The Project as proposed would be inconsistent with the following provision of East of 101 Area Plan policy DE-56: Parking Lot Trees: Cars should not be parked more than twelve in a row without a planting island that contains at least one tree. This inconsistency would be a potentially significant impact of the proposed Project. ^ MITIGATION MEASURE 8: Parking Lot Reconfiguration. The proposed Project parking lot shall be reconfigured in a way that conforms to all provisions of East of 101 Area Plan policy DE-56. This would reduce the impact to a level of less than significant with mitigation. c) Conflict with Conservation Plan Construction of the Cell Genesys Development would require cutting down thirty-three (33) trees and several extensively shrubbed areas located on the Project site. Eight (8) of the trees on the site are considered protected trees under Section 13.30.020(f)(1) of the City of South San Francisco Municipal Code relating to tree preservation (Tree Ordinance). More information on this topic is included in the Biological Resources section of this report. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 67 Environmental Factors and Focused Questions for Potentially Less Than Less Than Determination of Environmental Impact Significant Significant with Significant No Impact Mkiaation Impact Impact X. MINERAL RESOURCES -Would the Project: a) 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? b) 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? Setting No mineral resources of value to the region and the residents of the state have been identified at the Project site. The Project site has not been delineated as a locally important mineral recovery site on the City of South San Francisco General Plan, on any specific plan, or on any other land use plan. Impact Threshold of Significance: The Project would have a significant environmental impact if it were to 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, or if it were to 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. The development of the Cell Genesys Development at the Project site would not affect the availability of and would have no impact on any known mineral resource, or result in the loss of availability of any locally important resource recovery site. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE ('J8 Environmental Factors and Focused Questions for Potentialy Less Than Less Than Determination of Environmental Impact Signifcanrt Signficant with Significant No Impact Mitigation Impact lmaact XI. NOISE -Would the Project: a) Exposure of persons to or generation of noise [ ] [ ] [ / ] [ ] levels in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies? b) Exposure of persons to or generation of [ ] [ ] [ ] [ ./ ] excessive groundbome vibration or groundbome noise levels? c) A substantial permanent increase in ambient [ ] [ ] [ ] [ / ] noise levels in the Project vicinity above levels existing without the Project? d) A substantial temporary or periodic increase in [ ] [ /] [ ] [ ] ambient noise levels in the Project vicinity above levels existing without the Project? e) For a Project located within an airport land use [ ] ( ] [ ] [ ./] plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, would the Project expose people residing or working in the Project area to excessive noise levels? f) For a Project within the vicinity of a private [ ] [ ] [ ] [ / ] airstrip, would the Project expose people residing or working in the Project area to excessive noise levels? Setting Noise is generally defined as unwanted sound. Whether a sound is unwanted depends on when and where it occurs, what the listener is doing when it occurs, characteristics of the sound (loudness, pitch and duration, speech or music content, irregularity) and how intrusive it is above background sound levels. In determining the daily level of environmental noise, it is important to account for the difference in response of people to daytime and nighttime noises. During nighttime, exterior background noises are generally lower than daytime levels. However, most household noise also decreases at night and exterior noise becomes more noticeable. Further, most people sleep at night and are very sensitive to noise intrusion. Residential and open space recreational uses are generally considered to be noise-sensitive uses or sensitive receptors. There are no residential uses in the project vicinity, but there is a planned recreational trail designated along the railroad easement immediately south of the site. The trail could be located as close as approximately 150 feet from the proposed buildings and trail users would be subject to noise increases associated with project operation. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 69 However, it is anticipated that project construction would be completed prior to trail construction. Therefore, trail users would not be affected by project construction. In South San Francisco, the Noise Element of the City's General Plan (1999) contains land use criteria for noise-impacted areas. These criteria define the desirable maximum noise exposure of various land uses in addition to certain conditionally acceptable levels contingent upon the implementation of noise reduction measures. These criteria indicate that noise levels of less than 75 dBA (CNEL)15 are acceptable noise levels for industrial and open space uses. The South San Francisco Noise Ordinance (Chapter 8.32, Noise Regulations, Section 8.32.030) specifies the maximum permissible sound levels for residential, commercial and industrial land uses. The project site is zoned "M-1, Industrial," and the noise level standard for this zone is 70 dBA (Lso).16 Shorter periods of noise levels higher than these limits are allowed, but only for specified periods of time. Specifically, the standard + 5 dB for more than 15 minutes, the standard + 10 dB for more than 5 minutes, and the standard + 15 dB for more than one minute in any hour are used. The standard + 20 dB cannot be exceeded for any period of time. However, where the existing ambient noise level already exceeds the above noise limits, the ambient noise level becomes the standard. The South San Francisco Noise Ordinance (Chapter 8.32, Section 8.32.050) restricts construction activities to the hours of 8:00 a.m. to 8:00 p.m. on weekdays, 9:00 a.m. to 8:00 p.m. on Saturdays, and 10:00 a.m. to 6:00 p.m. on Sundays and holidays. This ordinance also limits noise generation of any individual piece of equipment to 90 dBA at 25 feet or at the property line. 15 The decibel (dB) is a logarithmic unit used to quantify sound intensity. Since the human ear is not equally sensitive to all sound frequencies within the entire spectrum, human response is factored into sound descriptions in a process called "A-weighting" written as "dBA". CNEL: Community Noise Equivalent Level. Because community receptors are more sensitive to unwanted noise intrusion during the evening and at night, state law requires that for planning purposes, an artificial dB increment be added to quiet time noise levels in a 24-hour noise descriptor called the Community Noise Equivalent Level (CNEL). 16 The noise limit that cannot be exceeded for more than 30 minutes in any hour (50 percent of any given hour). INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 7O a) Exposure of Persons To or Generation of Noise Levels in Excess of Standards Impact Threshold of Significance: The Project would have a significant environmental impact if it were to result in exposure of persons to or generation of noise levels in excess of standards established in the City of South San Francisco General Plan or the City's Noise Ordinance. Traffiic. Implementation of the proposed project would increase traffic noise levels along local streets due to project-generated traffic. It is anticipated that traffic-related noise increases associated with the project would be less than significant due to the low level of project- related traffic increases on local roadways. In general, a doubling of traffic volumes would be required to result in a 3-dBA noise increase in atraffic-dominated noise environment, and a 3- dBA noise increase is barely perceptible to most people. Project-related traffic increases on local roadways (well below a 100 percent increase) would result in traffic noise increases well below 3 dBA. Mechanical Equipment. Implementation of the proposed project would increase ambient noise levels in the project vicinity due to operation of rooftop mechanical equipment. The noise level from a single, roof-mounted "package" HVAC (heating, ventilation, and air conditioning) unit is typically rated at a sound power level of 8.4 bets. The proposed complex could require a distributed system of perhaps ten (10) such units, plus smaller heat pumps, fans and other mechanical equipment. Assuming there is a direct line-of--sight between the HVAC unit and planned trail and a 180-foot separation is maintained, noise levels could reach 50 dBA (Lso or Leq)," which would be well below the City Noise Ordinance 70-dBA noise limit (no noise attenuation assumed from proposed equipment screens and roof edge or parapet). Even if this unit were assumed to operate 24 hours per day, the 24-hour noise level generated by the HVAC unit would not exceed the City's 75-dBA (CNEL) land use criteria for industrial and open space uses. It is anticipated that roof parapets could reduce noise levels by at least 5 dBA. The impact of the HVAC system would be considered less than significant. b) Exposure of Persons To or Generation of Excessive Groundborne Vibrations or Groundborne Noise Levels Impact Threshold of Significance: The Project would have a significant environmental effect if it were to expose people to, or generate, excessive groundborne vibrations or groundborne noise levels. " Leq: The energy equivalent noise level; asteady-state energy level which represents the acoustical energy of a given measurement period that is equal to the actual time-varying sound level measured during the same period. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 7'I The development and operation of the Cell Genesys Development at the Project site would not involve the generation of excessive groundborne vibration or groundborne noise. It would have no impact related to the exposure of those closest to the Project site to excessive groundborne vibration or excessive groundborne noise levels. c) Substantial Permanent Increase in Ambient Noise Levels Impact Threshold of Signif cance: The Project would have a significant environmental impact if it were to result in a substantial permanent increase in ambient noise levels in the Project vicinity above levels existing without the Project. Although site preparation and the construction of the proposed Cell Genesys Development would be expected to result in a temporary increase in ambient noise levels in the Project vicinity, the on-going-operation of the Cell Genesys Development at the Project site would not result in a substantial permanent increase in ambient noise levels, thereby representing no impact. d) Substantial Temporary or Periodic Increase in Ambient Noise Levels Impact Threshold of Significance.• The Project would have a significant environmental impact if it were to result in a substantial temporary or periodic increase in ambient noise levels in the Project vicinity above levels existing without the Project. During site preparation and construction of the Cell Genesys Development at the Project site, the operation of heavy equipment could result in a substantial temporary increase in ambient noise levels in the vicinity of the Project site. ^ IMPACT 9: Construction Related Noise. Project construction would result in temporary short-term noise increases due to the operation of heavy equipment. This would represent a potentially significant impact associated with Project development. Construction noise sources range from about 82 to 90 dBA at 25 feet for most types of construction equipment, and slightly higher levels of about 94 to 97 dBA at 25 feet for certain types of earthmoving and impact equipment. ^ MITIGATION MEASURE 9: Limitation of Construction Hours/Noise Abatement. There are no existing noise-sensitive receptors in the project vicinity that would be affected by project-generated construction noise. However, neighboring INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 7Z businesses would be subjected to high noise levels during site preparation and construction. Although the highest noise levels would be generated by rock drills and pile drivers (which can generate noise peaks of approximately 98 and 101 dBA at 50 feet, respectively), such equipment would not be used for this project. If noise controls are installed on construction equipment, the noise levels could be reduced to 80 to 85 dBA at 25 feet, depending on the type of equipment. Assuming construction noise levels comply with the 90-dBA noise limit and hourly restrictions specified in the City Noise Ordinance, construction-related noise impacts could be reduced to a level of less than significant with mitigation. e/f) Location in Vicinity of a Public Airport or Private Airstrip Impact Threshold of Significance: The Project would have a significant environmental impact if it were located within an airport land use plan (or, where such a plan has not been adopted, within two miles of a public airport or public use airport) if it would expose people residing or working in the Project area to excessive noise levels, or if it were located within the vicinity of a private airstrip, if it would expose people residing or working in the Project area to excessive noise levels. The South San Francisco Noise Element (1999) contains existing and future (2006) airport noise contours associated with San Francisco International Airport, located south of the site. These contours indicate the project site is located outside the 65-dBA (CNEL) existing and future airport noise contours. Projected contours for road and railroad noise are also included in the Noise Element. These contours indicate that the project site is located in an area where noise levels generated by major road and railroad noise sources will continue to be less than 60 dBA (CNEL). Based on the City's land use criteria, the proposed Project's research and development type land use would be compatible with future noise level projections in the project vicinity of less than 60 to 65 dBA (CNEL), thereby representing no impact. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 73 Environmental Factors and Focused Questions for Potentially Less Than Less Than Determination of Environmental Impact Significant Significant with Significant No Impact Mkigation Impact Impact XII. POPULATION AND HOUSING -Would the Project: a) Induce substantial population growth in an area, ( ~ ( ~ ( ~ (/ either directly (for example, by proposing new homes and businesses) or indirectly (for example, through extension of roads or other infrastructure)? b) Displace substantial numbers of existing ( ~ ( ~ ( ~ (/ housing, necessitating the construction of replacement housing elsewhere? c) Displace substantial numbers of people, ( ~ ( ~ ( ~ (/ necessitating the construction of replacement housing elsewhere? Impact Threshold of Significance: The Project would have a significant environmental impact if it were to induce substantial population growth, or if it were to result in the displacement of substantial numbers of existing housing units, or in the displacement of substantial numbers of people living at the Project site. Development of the Cell Genesys Development at the Project site would not entail the extension of infrastructure that could support additional residential or commercial development. It would not involve the construction of any new housing, and would not require the displacement of any existing residential units or persons living on-site. Therefore, the Project would have no impact on population and housing in the area. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 74 Environmental Factors and Focused Questions for Potentially Less Than Less Than Determination of Environmental Impact Sign cant Significant with Significant No Imaad Mkination Impact Imoad XIII. PUBLIC SERVICES a) Would the Project result in substantial adverse physical impacts associated with the provision of new or physically altered govemmental facilities, need for new or physically altered governmental facilities, the construction of which could cause significant environmental impacts, in order to maintain acceptable service ratios, response times or other performance objectives for any of the public services: i) Fire protection? ii) Police protection? iii) Schools? iv) Parks? v) Other public facilities? /~ /~ /~ /~ /~ Impact Threshold of Significance: The Project would have a significant environmental impact if it were to result in substantial adverse physical impacts associated with the provision of new or physically altered governmental facilities, the construction of which could cause significant environmental impacts, in order to maintain acceptable service ratios, response times or other performance objectives for fire protection, police protection, schools, parks and recreational facilities, or other government facilities. The proposed Project would place a less than signiftcant increased demand on City of South San Francisco public services. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE T5 Environmental Factors and Focused Questions for Potentialy Less Than Less Than Determination of Environmental Impact Significant Significant with Significant No Impact Mkigation Impact Impact XIV. RECREATION - a) Would the Project increase the use of existing ( ] [ ] ( ] (~/ ] neighborhood and regional parks or other recreational facilities such that substantial physical deterioration of the facility would occur or be accelerated? b) Does the Project include recreational facilities ( ] ( ] [ ] [ ~/] or require the construction or expansion of recreational facilities, which might have an adverse physical effect on the environment? Impact Threshold of Signifzcance: The Project would have a significant environmental impact if it were to result in an increase in the use of existing parks or recreational facilities such that substantial physical deterioration of these facilities could be anticipated, or if it were to include recreational facilities, the construction of which might have adverse physical effects on the environment. The Project would have no impact on parks or recreational facilities since it does not involve any development that would result in an increase in the use of existing parks or recreational facilities, and does not incorporate their construction. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 76 Environmental Factow and Focused Questions for Potentially Less Than Less Than Determination of Environmental Impact Significant Significant with Significant No Impact Mitigation Impact Impact XV. TRANSPORTATIONITRAFFIC -Would the Project: a) Cause an increase in traffic, which is substantial ( ] ( ] (/] ( ] in relation to the existing traffic load and capacity of the street system (i.e., result in a substantial increase in either the number of vehicle trips, the volume to capacity ratio on roads, or congestion at intersections)? b) Exceed, either individually or cumulatively, a ( ] ( ] ( ] (/ ] level of service standard established by the county congestion management agency for designated roads or highways? c) 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? d) Substantially increase hazards due to a design ( ] (/] ( ] ( ] feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment)? e) Result in inadequate emergency access? [ ] [ ] ( ] (/ ] f) Result in inadequate parking capacity? ( ] ( ] (/] ( ] g) Conflict with adopted policies, plans, or ( ] ( ] ( ] (/ ] programs supporting alternative transportation (e.g., bus turnouts, bicycle racks)? Setting ROADWAYS The project site is served directly by Forbes Boulevard and Allerton Avenue. Additional local area access is also provided by Eccles Avenue, as shown in Figure 1 of the traffic analysis included as Appendix B. Each roadway is briefly described below while a schematic presentation of intersection approach lanes and intersection control are presented in Figure 2 of Appendix B. Forbes Boulevard is a four-lane roadway running in a general east-west direction along the north side of the project site. Each travel lane is 12 feet wide. It has a raised landscaped median with median breaks at intersections and driveways. The posted speed limit is 35 miles per hour and on-street parking is prohibited (there is no room for on-street parking within the existing lane widths). Forbes Boulevard is all-way-stop controlled at Eccles Avenue, but is not signal or stop sign controlled on the approaches to Allerton Avenue. Left turn deceleration INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE TT lanes are not provided on the approaches to Allerton Avenue or driveways in the vicinity of the project site. Curb, gutter and sidewalk are provided along the north side of the street while curb and gutter only are provided on the south (Project) side of the street. Allerton Avenue is a two-lane, 40-foot-wide roadway extending southerly from Forbes Boulevard for about half a mile before ending at East Grand Avenue. The Allerton Avenue approaches to both Forbes Avenue and East Grand Avenue are stop sign controlled while the posted speed limit is 30 miles per hour. Curb, gutter and sidewalk are provided along the west side of the street while curb and gutter only are provided along the east (project) side of the street. Left turn lanes are not provided on the approach to any intersection or driveway. On-street parking is prohibited along both sides of the street in the vicinity of the project. Eccles Avenue is a two-lane, 40-foot-wide roadway extending northerly from Forbes Boulevard for about half a mile to a connection with Oyster Point Boulevard. It has an all- way-stop intersection with Forbes Boulevard and a signalized intersection with Oyster Point Boulevard. A single track industrial spur railroad line extends through the Eccles Avenue/Forbes Boulevard intersection. VOLUMES Weekday AM and PM peak period (7:00-9:00 AM and 4:00-6:00 PM) vehicle, pedestrian and bicycle counts were conducted by Crane Transportation Group on June 27, 2001 at the Forbes Boulevard/Allerton Avenue and Forbes Boulevard/Eccles Avenue intersections. The peak hours were determined to be 7:45 to 8:45 AM and 4:45 to 5:45 PM. Resultant AM and PM peak hour traffic volumes are presented in Figure 3 of the traffic analysis included as Appendix B. Only minor levels of pedestrians and bike riders were observed at either intersection during either survey period. During the two-hour AM peak period seven bike riders passed through both the Forbes Boulevard/Allerton Avenue and Forbes Boulevard/Eccles Avenue intersections, while only one pedestrian crossed Forbes Boulevard at Allerton Avenue. During the two-hour PM peak period six bike riders passed through the Forbes Boulevard/Allerton Avenue intersection while 13 bike riders passed through the Forbes Boulevard/Eccles Avenue intersection. Only one pedestrian crossed Forbes Boulevard at Allerton Avenue during the PM peak period. INTERSECTION OPERATION INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE TS 1. Analysis Methodology Signalized Intersections. Intersections, rather than roadway segments between intersections, are almost always the capacity controlling locations for any circulation system. Signalized intersection operation is graded based upon two different scales. The first scale employs a grading system called Level of Service (LOS) which ranges from Level A, indicating uncongested flow and minimum delay to drivers, down to Level F, indicating significant congestion and delay on most or all intersection approaches. The Level of Service scale is also associated with an average vehicle delay tabulation (1994 Highway Capacity Manual [HCM] operations method) at each intersection. The vehicle delay designation allows a more detailed examination of the impacts of a particular project. Greater detail regarding the LOS/delay relationship is provided in the Appendix of Crane Transportation Group's traffic analysis. Unsignalized Intersections. Unsignalized intersection operation is also typically graded using the Level of Service A through F scale. LOS ratings for all-way stop intersections are determined using a methodology outlined in the 1994 update of the Highway Capacity Manual (TRB Circular 209). Under this methodology, all-way stop intersections receive one LOS designation reflecting operation of the entire intersection. Average vehicle delay values are also calculated. Intersections with side streets only stop sign controlled are also evaluated using the LOS and delay scales using a methodology outlined in the 1994 Highway Capacity Manual. However, unlike signalized or all-way stop analysis where the LOS and delay designations pertain to the entire intersection, in side street stop sign control analysis LOS and delay designations are computed for stop sign controlled approaches or individual turn and through movements rather than for the entire intersection. The Appendix provides greater detail about unsignalized analysis methodologies. 2. Standards The City of South San Francisco considers Level of Service D (LOS D) to be the poorest acceptable operation for signalized and all-way-stop intersections and LOS E to be the poorest acceptable operation for unsignalized city street intersection turn movements. The City has no standards for turn movements from private driveways. 3. Existing Operating Conditions Table 1 of the traffic analysis included as Appendix B shows that currently the all-way-stop Forbes Boulevard/Eccles Avenue intersection is operating at acceptable levels of service during both commute periods (LOS C during both the AM and PM peak traffic hours). At the Forbes Boulevard/Allerton Avenue intersection, movements from the stop sign INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 79 controlled Allerton Avenue approach are also operating acceptably during both commute periods (LOS B during both the AM and PM peak traffic hours). D. INTERSECTION SIGNALIZATION REQUIREMENTS Traffic signals are used to provide an orderly flow of traffic through an intersection. Many times they are needed to offer side street traffic an opportunity to access a major road where high volumes and/or high vehicle speeds block crossing or turn movements. They do not, however, increase the capacity of an intersection (i.e., increase the overall intersection's ability to accommodate additional vehicles) and, in fact, often slightly reduce the number of total vehicles that can pass through an intersection in a given period of time. Signals can also cause an increase in traffic accidents if installed at inappropriate locations. There are 11 possible tests for determining whether a traffic signal should be considered for installation. These tests, called "warrants", consider criteria such as actual traffic volume, pedestrian volume, presence of school children, and accident history. Usually, two or more warrants must be met before a signal is installed. In this report, the test for Peak Hour Volumes (Warrant #11) has been applied. When Warrant 11 is met there is a strong indication that a detailed signal warrant analysis covering all possible warrants is appropriate. These rigorous analyses are described in Chapter 9 of the Caltrans Traffic Manual while Warrant 11 is presented in the Appendix within Crane Transportation Group's traffic analysis. Currently, neither the Forbes Boulevard/Allerton Avenue nor the Forbes Boulevard/Eccles Avenue intersections have AM or PM peak hour volumes meeting peak hour signal warrant criteria levels. E. OBSERVED SAFETY CONCERNS The Forbes Boulevard pavement is deteriorated in several locations. In addition, uneven pavement covering past trenching in the eastbound and westbound curb travel lanes creates uncomfortable driving conditions and a safety hazard for bicycle riders. The lack of an exclusive left turn lane on the Forbes Boulevard westbound approach to Allerton Avenue increases the chances for rear-end accidents between a vehicle slowing or stopped waiting to turn left and a higher speed through vehicle. The wide median break along Forbes Boulevard at this location does, however, provide an informal storage (refuge) area for turning vehicles. F. PLANNED IMPROVEMENTS INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE SO There are plans to repave Forbes Boulevard by the end of August, 200118 and the Forbes Boulevard/Eccles Avenue intersection is programmed to be signalized by the end of 2002.19 a) Cause an Increase in Traffic, Which is Substantial in Relation to Existing Traffic Load and Capacity of the Street System Impact Threshold of Significance: City of South San Francisco policy defines a significant impact as one where signalized and all-way-stop intersections operate below Level of Service D (LOS D) or below LOS E for unsignalized City street intersection turn movements. The City has no standards for turn movements from private driveways. Existing + Approved Development (Base Case) Operating Conditions Volumes. AM and PM peak hour trip generation and distribution projections were developed for currently approved or under construction developments in South San Francisco to the east of the U.S.101 freeway. Approved projects and their expected trip generation are presented in Table 2 of the traffic analysis included as Appendix B. Both trip rates and regional distribution patterns applied to each approved development are contained in the April 2001 Draft Supplemental EIR for the South San Francisco General Plan Amendment and Transportation Demand Management Ordinance. At the request of City Planning staff, peak hour trip generation from each approved project has been reduced by 35% to reflect implementation of Transportation Demand Management (TDM) measures.20 Resultant existing + approved development (Base Case) AM and PM peak hour volumes are presented in Figure 4 of the traffic analysis included as Appendix B. Intersection Operation. For Base Case analysis purposes, the Forbes Boulevard/Eccles Avenue intersection has been assumed to be signalized. Table 1 of the traffic analysis shows that a signalized Forbes Boulevard/Eccles Avenue intersection would operate at good levels of service as an all-way-stop with Base Case volumes (LOS A during both the AM and PM peak traffic hours). At the Forbes Boulevard/Allerton Avenue intersection, the stop sign controlled Allerton Avenue approach would continue to operate at acceptable levels of service during both commute periods (LOS B during both the AM and PM peak traffic hours). 1e Steve Carlson, Senior Planner, City of South San Francisco Planning Department. 19 Richard Harmon, Development Review Coordinator, South San Francisco Public Works Department. 20 Measures could include (but not be limited to) provision of birycle lockers and racks as well as showers and changing rooms, operation of a shuttle to BART and Caltrain, subsidizing transit tickets for employees, creation of preferential parking for car and vanpoolers, implementation of a vanpool program, facilitating employee telecommuting, flexible work hours, provision of child care services, etc. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE H'I Volumes at this location would not be increased to meet peak hour signal warrant criteria levels with the addition of approved development traffic. Trip Generation. Table 3 of the traffic analysis shows that the Project's 154,000 square feet of research and development space (in two buildings) would be expected to generate 83 inbound and 17 outbound trips during the AM peak hour, with 14 inbound and 79 outbound trips during the PM peak hour. These projections are based upon trip rates from existing research and development facilities in the East of 101 area and do not include any significant reduction in peak hour trip generation due to TDM measures. Should Cell Genesys develop a significant TDM program and reach the City's desired goal of 35 percent reduction in peak hour traffic, trip generation would be reduced to 54 inbound and 11 outbound trips during the AM peak hour with 9 inbound and 52 outbound trips during the PM peak hour. Trip Distribution. Project traffic was distributed to the subregional roadway network based upon East of 101 development traffic patterns contained in the April 2001 Draft SEIR for the South San Francisco General Plan Amendment and Transportation Demand Ordinance. Overall, about 62 percent of Project traffic should be destined to/from south and southwest of the site, with 38 percent destined to/from the north and northwest. However, it is likely that some Project drivers destined to/from the south on the U.S. 101 freeway would choose to access the freeway via Oyster Point Boulevard, which is north of the site. Project traffic is shown distributed to the local roadway network with Base Case volumes in Figure 4 for AM and PM peak hour conditions, while Figure 5 of the traffic analysis included as Appendix B presents expected Project traffic turn movements at each of the site driveways. Intersection Impacts. Table 1 of the traffic analysis shows that a signalized Forbes Boulevard/Eccles Avenue intersection would continue to operate at good levels of service as an all-way-stop with Base Case + project volumes (LOS A during both the AM and PM peak traffic hours). Project traffic would increase average vehicle delay about two tenths of a second during the AM peak hour and not produce a measurable change in delay during the PM peak hour. At the Forbes Boulevard/Allerton Avenue intersection, the stop sign controlled Allerton Avenue approach would continue to operate at acceptable levels of service during both commute periods (LOS B during the AM peak hour and changing from LOS B to an acceptable LOS C during the PM peak hour). The Forbes Boulevard/Allerton Avenue intersection would not have volumes increased to meet peak hour signal warrant criteria levels with the addition of Project traffic to Base Case volumes. The Project would place a less than signftcant demand on the existing street system. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE HZ b) Direct or Cumulative Increase in Traffic Which Causes a Congestion Management Agency Standard to be Exceeded Impact Threshold of Significance: The Project would have a significant environmental impact if it were to result in a direct increase in traffic that would cause a Congestion Management Agency standard to be exceeded, or contribute substantially to a cumulative increase in traffic that would cause a Congestion Management Agency standard to be exceeded. The Project would have no impact related to an exceedance of a Congestion Management Agency level of service standard. c) Change in Air Traffic Patterns Impact Threshold of Significance: The Project would have a significant environmental impact if it were to result in a change in air traffic patterns that results in substantial safety risks. The Project would have no impact on air traffic patterns. d) .Hazards Due to Design Features Impact Threshold of Significance: The Project would have a significant environmental impact if it were to substantially increase hazards due to a design feature or incompatible uses. ^ IMPACT 10: Blocked Sight Lines. Access to the Project site would be provided via one driveway connection to Forbes Boulevard about 25 feet from the east end of the Project frontage and one driveway connection to Allerton Avenue about 25 feet from the south end of the Project frontage. At the Forbes Boulevard driveway intersection the sight line to the west to see eastbound traffic is about 450 feet, while the sight line to the east to see westbound traffic is greater than 500 feet. However, the height of the berm and landscaping in the two 75-foot-long raised medians just east of the proposed site driveway along Forbes Boulevard could partially block sight lines between drivers leaving the Project site and westbound traffic on Forbes Boulevard, particularly for cars riding low to the ground. This would be a potentially significant impact of the Project. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE H3 ^ MITIGATION MEASURE 10: Berm Height Reduction. The height of the berm in the two median islands along Forbes Boulevard should be reduced just east of the proposed Project driveway. Landscaping should be replaced as required. This would reduce the impact of blocked sight lines to a level of less than significant with mitigation. At the Allerton Avenue driveway, the sight line to the north extends about 375 feet to the Forbes Boulevard intersection, while the sight line to the south extends more than 500 feet. Observed vehicle speeds on Forbes Boulevard ranged as high as 45 miles per hour. An acceptable stopping sight distance at this speed is 360 feet.21 Along Allerton Avenue, observed speeds ranged as high as 40 miles per hour. An acceptable stopping sight distance at this speed is 305 feet. Therefore, sight lines at both driveways should be adequate, with the concern detailed above that the height of the two raised medians along Forbes Boulevard just east of the Project driveway could partially block sight lines for low riding vehicles. ^ IMPACT 11: Forbes Boulevard Median. Figure 6 of the traffic analysis included as Appendix B shows that a 75 foot-long landscaped median is in place along Forbes Boulevard at the location of the proposed Project driveway. The driveway and/or the island's location would preclude direct left turn movements to/from the Project driveway and would result in a significant number of U-turns at either end of the island. This would create significant traffic safety and operational concerns as Project drivers would slow to conduct U-turns in the higher speed through travel lanes of Forbes Boulevard. In addition, the island's 12-foot width would not be great enough to provide refuge for the entire length of most U-turning vehicles. This would be a potentially significant impact of the Project. ^ MITIGATION MEASURE 11: Street Re-Configuration. The raised median along Forbes Boulevard at the location of the proposed Project driveway should be removed. In addition, a continuous two-way left turn lane should be striped that would extend easterly from the Project driveway to serve the existing driveway on the adjacent property about 50 feet to the east. This would reduce the impact to a level of less than significant with mitigation. In addition, in Base Case (without Project) conditions, a left turn deceleration lane on the westbound Forbes Boulevard approach to Allerton Avenue should be provided. This would require removal of the 75-foot long raised median that starts about 30 feet east of the Allerton Avenue intersection. 21 A policy on geometric Design of Highways and Streets, Fourth Edition, AASHTO, 2001. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE H4 e) Emergency Access Impact Threshold of Significance: The Project would have a significant environmental impact if it were to provide inadequate emergency access to the Project site. The Cell Genesys Development would be built in a manner consistent with City of South San Francisco building codes. There would be no impact related to inadequate emergency access to the site. f) Parking Capacity Impact Threshold of Significance: the Project's impact on parking shall be considered significant if the Project does not meet the City of South San Francisco's parking space requirements and/or the proposed parking plan is not adequate in number or design to serve the proposed Project. The Project would provide 1 parking space per 360 square feet of building space, based on the Project's 154,000 of building space and 427 planned parking spaces. The City requirement for this type of building is one space per 354 square feet of building space. The Project is not in compliance with the City requirement. However, even a marginal compliance with the City's Transportation Demand Management Ordinance would offset the shortfall in required parking spaces on site by reducing the demand for parking, thereby representing a less than significant impact. g) Alternative Transportation Impact Threshold of Significance: The Project would have a significant environmental impact if it were to conflict with adopted policies, plans, or programs supporting alternative transportation. The Project would have no impact on alternative transportation. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 8rJ Environmental Factors and Focused Questions for Potentially Less Than Less Than Determination of Environmental Impact Significant Significant with Significant No Impact Mitigation Impact Impact XVI. UTI LITIES AND SERVICE SYSTEMS -Would the Project: a) Exceed wastewater treatment requirements of (~ ] ( ] [ ] [ / ] the applicable Regional Water Quality Control Board? b) Require or result in the construction of new ( ] [ ] [ ] [ / ] water or wastewater treatment facilities or expansion of existing facilities, the construction of which could cause significant environmental effects? c) Require or result in the construction of new [ ] [ ] [ ] [ / ] storm water drainage facilities or expansion of existing facilities, the construction of which could cause significant environmental effects? d) Have sufficient water supplies available to serve [ ] [ ] [ ] [ / ] the Project from existing entitlements and resources, or are new or expanded entitlements needed? e) Result in a determination by the wastewater [ ] ( ] [ / ] [ ] treatment provider, which serves or may serve the Project that it has adequate capacity to serve the Project's Projected demand in addition to the provider's existing commitments? f) Be served by a landfill with sufficient permitted [ ] [ ] (/ ] ( ] capacity to accommodate the Project's solid waste disposal needs? g) Comply with federal, state, and local statutes [ ] [ ] [ ] [ /] and regulations related to solid waste? a) Regional Wastewater Treatment Standards Impact Threshold of Signifzcance: The Project would have a significant environmental impact if it were to exceed wastewater treatment requirements of the applicable Regional Water Quality Control Board. The project would have no impact related to an exceedance of wastewater treatment requirements of the Regional Water Quality Control Board. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE H6 b) Water and Wastewater Treatment Facilities Impact Threshold of Significance: The Project would have a significant environmental impact if it were to require the construction of new water or wastewater treatment facilities or expansion of existing facilities, the construction of which could cause significant environmental effects. The Project would have no impact .related to the construction or expansion of water or wastewater treatment facilities. c) Storm Water Drainage Facilities Impact Threshold of Significance: The Project would have a significant environmental impact if it were to require or result in the construction of new storm water drainage facilities or in the expansion of existing facilities, the construction of which could cause significant environmental effects. The Project would have no impact related to the construction of new storm water drainage facilities or their expansion. d) Water Supply Impact Threshold of Significance: The Project would have a significant environmental impact if it were to require additional water supply beyond that available from existing entitlements and resources. The Project would utilize existing water entitlements and resources, having no impact on other water resources. e) Wastewater Treatment Facility Capacity Impact Threshold of Significance: The Project would have a significant environmental impact if it were to result in a determination by the wastewater treatment provider which may serve the Project that it has inadequate capacity to serve the Project's projected demand in addition to the provider's existing commitments. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE H7 The Project would place a less than significant demand on the area's wastewater treatment provider and would not prevent it from fulfilling its existing commitments. f) Solid Waste Disposal Capacity Impact Threshold of Significance: The Project would have a significant environmental impact if it were to be served by a landfill with inadequate permitted capacity to accommodate the Project's solid waste disposal needs. The construction and operation of the Cell Genesys Development at the Project site would generate a less than signifzcant amount of solid waste. g) Compliance With Solid Waste Regulations Impact Threshold of Significance: The Project would have a significant environmental impact if it were to fail to fully comply with federal, state, and local statutes and regulations related to solid waste. The operation of the proposed Cell Genesys Development at the Project site would be expected to be in full compliance with all federal, state and local statutes and regulations related to solid waste, thereby having no impact. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 8H Environmental Factors and focused Questions for Fotentialy Less Than Less Than Determination of Environmental Impact Significant Significant with Signficant No Impact Mkiaation Impact Impact XVII. MANDATORY FINDINGS OF SIGNIFICANCE - a) Does the Project have the potential to degrade [ ] [ /] [ ] [ ] the quality of the environment, substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below self-sustaining levels, threaten to eliminate a plant or animal community, reduce the number or restrict the range of a rare or endangered plant or animal or eliminate important examples of the major periods of California history or prehistory? b) Does the Project have impacts that are ( ] [ ] ( ] (/] individually limited, but cumulatively considerable? ("Cumulatively considerable" means that the incremental effects of a Project are considerable when viewed in connection with the effects of past Projects, the effects of other current Projects, and the effects of probable future Projects.) c) Does the Project have environmental effects, ( ] [ /] [ ] [ ] which will.cause substantial adverse effects on human beings, either directly or indirectly? a) Quality of the Environment Implementation of the Project does not have the potential to degrade the quality of the environment, substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below self-sustaining levels, threaten to eliminate a plant or animal community, reduce the number or restrict the range of a rare or endangered plant or animal or eliminate important examples of major periods of California history or prehistory. There are no Project-related environmental impacts that would not be reduced to a level of less than significant through the implementation of the mitigation measures identified above. b) Cumulative Impacts The Project does not involve environmental impacts that are individually limited, but cumulatively considerable when viewed in connection with the effects of past projects, the effects of other current projects, and the effects of probable future projects. There are no Project-related cumulative impacts. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE H9 c) Adverse Environmental Effects on Human Beings The Project would not have environmental effects, which will cause substantial adverse effects on human beings, either directly or indirectly, because the Project is consistent and compatible with agricultural land uses in the surrounding area. The implementation of the mitigation measures identified above would reduce potentially significant Project-related environmental impacts to a level of less than significant. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 9O REFERENCES BIBLIOGRAPHY Bay Area Air Quality Management District, BAAQMD CEQA Guidelines: Assessing the Air Quality Impacts of Projects and Plans, April 1996. Bay Area Air Quality Management District, BAAQMD CEQA Guidelines, p.23,24. Bay Area Air Quality Management District, "Bay Area Attainment Status" April 1999 (obtained at BAAQMD website: www.baagmd.gov). Bay Area Air Quality Management District, Summary of Air Pollution in the Bay Area, individual sheets for 1995-1999; and various Press Releases, Office of Public Information, Education Division, August 1997 through January 2001. Brady and Associates, East of 101 Area Plan, adopted July 1994. City of South San Francisco, South San Francisco Municipal Code Relating to Tree Preservation, adopted June 28, 2000. Crane Transportation Group, Tra~c Impact Study: Cell Genesys RFSD Off ce Building in South San Francisco, August 2, 2001. Dyett &Bhatia, City of South San Francisco General Plan, adopted October 1999. Dyett &Bhatia, South San Francisco General Plan: Existing Conditions and Planning Issues, prepared for the City of South San Francisco, September 1997. Geier & Geier Consulting, Air and Noise Analyses for Cell Genesys Development, August 2001. Treadwell & Rollo, Environmental Site Characterization: Cell Genesys, Inc. Corporate Headquarters and Research Center, S00 Forbes Boulevard, August 8, 2001. INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 9'I Treadwell & Rollo, Geotechnical Investigation: Cell Genesys, Inc. Corporate Headquarters ~ Research Center, S00 Forbes Boulevard, August 8, 2001. PERSONAL COMMUNICATIONS Steve Carlson, Senior Planner, City of South San Francisco. John Cavanaugh, Project Manager, Cell Genesys, Inc. Theresa Eckert and Tahee Lee, WHL Architects. Paul Reed, Reed Associates Landscape Architecture. REPORT AUTHORS Joan Lamphier, Principal John Courtney, Senior Planner Rudy Calderon, Planner INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 92 APPENDICES Appendix A List of Mitigation Measures ..........................................................................A-1 Appendix B Traffic Analysis ............................................................................................. B-1 INITIAL STUDY /MITIGATED NEGATIVE DECLARATION CELL GENESYS DEVELOPMENT PAGE 93 APPENDIX A LIST OF MITIGATION MEASURES ,~ ^ IMPACT 1: Generation of Particulate Matter. Construction of the proposed Cell Genesys Development would have short-term air quality effects, primarily due to the generation of particulate matter (PM-10). PM-10 is normally generated by diesel construction vehicles and equipment, the disturbance of soils through excavation and grading, construction vehicle travel on unpaved surfaces and the tracking of soils onto paved roads. Failure to implement appropriate dust control measures would be a potentially significant environmental impact, and would be inconsistent with the current Clean Air Plan. ^ MITIGATION MEASURE 1: Dust Control Measures. The BAAQMD's CEQA Guidelines (1999) acknowledges that construction activity emissions vary markedly from project to project, from day to day, and from one contractor to another. Rather than focus on a quantification of project-related emissions, the BAAQMD has developed a menu of mitigation options to control construction activity dust emissions. The BAAQMD (1999) considers implementation of all applicable dust control measures (which vary according to project magnitude) as reducing project- related particulate (I'Mio) emissions to less-than-significant levels. These measures are grouped into three categories as follows: • "Basic Control Measures" apply to all construction sites. • "Enhanced Control Measures" apply to sites greater than four acres. • "Optional Control Measures" apply to larger sites near sensitive receptors. Based on the project's 6.74-acre size, implementation of the Basic and Enhanced Control Measures listed below would maintain project construction-related impacts at a less than significant level. Construction equipment emits carbon monoxide and ozone precursors during combustion of diesel fuel. The BAAQMD's determination, however, is that these emissions have been included in the emissions inventory, which was the basis for the 1997 Clean Air Plan and subsequent air quality plans. Since the BAAQMD does not consider construction-related exhaust emissions to be "new" emissions, they would not impede attainment or maintenance of ozone or CO standards in the air basin (BAAQMD, 1999). Therefore, temporary increases in exhaust emissions would be considered less than significant. The following measure will be required during project construction to reduce construction emissions to a less than significant level: Construction activities must comply with the "Basic Control Measures" and "Enhanced Control Measures" for dust emissions as outlined in the BAAQMD CEQA Guidelines. These requirements are listed as follows: 1. Basic Control Measures • Water all active construction areas at least twice daily. • Cover all trucks hauling soil, sand, and other loose debris or require all trucks to maintain at least two feet of freeboard. • Pave, apply water three times daily, or apply (non-toxic) soil stabilizers on all unpaved access roads, parking areas, and staging areas at construction sites. • Sweep daily (with water sweepers) all paved access roads, parking areas, and staging areas at construction sites. • Sweep streets daily (with water sweepers) if visible soil material is carried onto adjacent public streets. 2. Enhanced Control Measures • Hydroseed or apply (non-toxic) soil stabilizers to inactive construction areas (previously graded areas inactive for ten days or more). • Enclose, cover, water twice daily or apply (non-toxic) soil binders to exposed stockpiles (dirt, sand, etc.). • Limit traffic speeds on unpaved roads to 15 mph. • Install sandbags or other erosion control measures to prevent silt runoff to public roadways. • Replant vegetation in disturbed areas as quickly as possible. The implementation of Mitigation Measure 1 would reduce the impact of dust from construction of the Project to a level of less than significant with mitigation. ^ IMPACT 2: Removal of Protected Trees. _Construction of the Cell Genesys Development would require cutting down thirty-three (33) trees and several extensively shrubbed areas located on the Project site. Eight (8) of the trees on the site are considered protected trees under Section 13.30.020(f)(1) of the City of South San Francisco Municipal Code relating to tree preservation (Tree Ordinance). According to the Ordinance, a protected tree is defined as the following: 1. Any tree with a circumference of 48 inches or more when measured 54 inches above natural grade; or 2. A tree or stand of trees so designated by the Director based upon findings that it is unique and of importance to the public due to its unusual appearance, location, historical significance or other factor; or 3. A stand of trees in which the Director has determined each tree is dependent upon the others for survival. The eight protected trees on the site are considered protected because their trunk circumferences measure more than 48 inches above natural grade. Cutting down these trees would be a potentially significant impact of the Project. ^ MITIGATION MEASURE 2: Tree Replacement. According to the Tree Ordinance, no protected tree shall be removed, pruned, or otherwise materially altered without a permit except as provided in Section 13.30.030. A tree cutting permit requires replacement of a tree with three 24-inch box or two 36-inch box minimum size landscape trees for each tree removed, as described in Section 13.30.080 of the Tree Ordinance. Adherence to the provisions of the City of South San Francisco Tree Ordinance would reduce the impact of cutting down eight protected trees on the Project site to a level of less than significant with mitigation. ^ IMPACT 3: Potential Disturbance of Archaeological Resources. The Project site is a previously disturbed, developed site where no known archaeological sites are located. However, given that archaeological remains have been found in the Project's vicinity, the presence of archaeological remains underneath the Project site cannot be discounted. The Project could have a significant impact on any archaeological remains discovered at the Project site. ^ MITIGATION MEASURE 3: Monitoring of Grading Process. A certified archaeologist shall be present at the Project site during the initial grading process to monitor grading activities and ensure the protection and preservation of any archaeological resources discovered at the Project site. This-would reduce the impact of the Project on archaeological resources to a level of less than significant with mitigation. ^ IMPACT 4: Adverse Effects of Seismic Related Ground Shaking. The proposed Cell Genesys Development would be occupied by Cell Genesys staff, who could be exposed to adverse effects related to seismic ground shaking. This would be a potentially significant impact of the Project. ^ MITIGATION MEASURE 4: Adherence to Geotechnical Engineering Recommendations. Treadwell and Rollo judge the soil and bedrock conditions at the Project site to be suitable from a geotechnical standpoint for the proposed construction, provided that their recommendations are incorporated into the Project plans and implemented during construction. Their recommendations are the following: Site Preparation and Grading. Grading operations should commence after demolition and removal of the existing building, pavements, floor slabs and underground utilities within the development area. Following demolition, all areas to receive improvements should be stripped of vegetation and organic topsoil. The pavement material, including asphalt, may be segregated from organic topsoil and used as compacted fill, provided it meets the fill requirements presented in a subsequent section of this report and is acceptable from an environmental standpoint. The stripped organic soil can be stockpiled for later use in landscaped areas, if approved by the architect. Organic topsoil should not be used as compacted fill. The surface exposed by stripping should be scarified to a depth of at least six inches, moisture-conditioned to above the optimum moisture content and compacted to at least 90 percent relative compaction.12 If soft or loose soil is encountered, the unsuitable material should be overexcavated and replaced with suitable fill material and similarly compacted and moisture conditioned. The exposed ground surface should be kept moist during subgrade preparation. Select fill should consist of on-site or imported soil that is non-corrosive, free of organic matter, contains no rocks or lumps larger than three inches in greatest dimension, has a liquid limit less than 40 and plasticity index less than 12, and is approved by the geotechnical engineer. In addition, the select fill should contain between 10 and 25 percent fines (particles passing the No. 200 sieve to reduce potential for surface water infiltration. It is likely the surface sand and gravel fill will meet the select fill criteria. Based on the plasticity and liquid limit criteria, the near- 1z Relative compaction refers to the in-place dry density of soil expressed as a percentage of the maximum dry density of the same material, as determined by the ASTM D1557-91 laboratory compaction procedure. surface residual soil is not expected to meet the criteria for select fill. A sample of the on-site and import material to be used as select fill should be submitted to the geotechnical engineer for testing at least three business days prior to use at the site. Fill should be placed in horizontal layers not exceeding eight inches in loose thickness, moisture-conditioned to above the optimum moisture content, and compacted as presented in Table 1. TABLE 1 COMPACTION REQUIREMENTS LOCATION REQUIRED COMPACTION (PERCENT) MOISTURE REQUIREMENT`:. Building pad -select fill 95+ Above optimum General fill -native soil backfill 90 - 93 3% above optimum General fill -select fill 90 + Above optimum Utility trench -native soil backfill 90 - 93 3% above optimum Utility trench -select fill 90 + Above optimum Utility trench -clean sand or gravel 95 + Above optimum AC pavement subgrade -native soil 95 Above optimum AC pavement subgrade -select fill 95+ Above optimum AC pavement -aggregate base 95+ Above optimum Concrete paving Same as AC pavement Same as AC pavement Concrete Flatwork -native soil 90 - 93 3% above optimum Concrete Flatwork -select fill/AB 90+ Above optimum Utility Trenches. Excavations for utility trenches can generally be made with a backhoe. Despite careful site preparation, obstructions and hard rock may be encountered rendering some of the trenching operations difficult. All trenches should conform to the current CAL-OSHA requirements. Backfill for utility trenches and other excavations is also considered fill, and should be compacted according to the recommendations presented in Table 1. Special care should be taken when backfilling utility trenches in pavement areas. Poor compaction may cause excessive settlements, resulting in damage to the pavement section. When necessary, trench excavations should be shored and braced to prevent cave-ins in accordance with all safety regulations. Where sheet piling is used as shoring, and is to be removed after backfilling, it should be placed a minimum of two feet away from the pipes or conduits to prevent disturbance to them as the sheet piles are extracted. Where trenches extend below the groundwater level, it will be necessary to temporarily dewater them to allow for placement of the pipe and/or conduits, and backfill. To provide uniform support, pipes or conduits should be bedded on a minimum of four inches of sand or fine gravel. After the pipes and conduits are tested, inspected (if required) and approved, they should be covered to a depth of six inches with sand or fine gravel, which should be mechanically tamped. Building Foundations. Provided that settlement of up to 'k inch is acceptable, the building may be supported on conventional spread footings bearing on native residual soil (sandy clay) or the shale and sandstone bedrock. Individual spread footings should be at least 36 inches square and continuous footings should be at least 24 inches wide and bottomed in the residual soil or bedrock. All footings should be founded a minimum of 24 inches below the lowest adjacent soil subgrade and 12 inches into residual soil or bedrock. The footings may be designed for allowable bearing pressures of 6,000 pounds per square foot (psf) for dead plus live loads and 8,000 psf for total design loads, including wind or seismic forces. Lateral loads can be resisted by a combination of passive pressure on the vertical faces of the footings and friction along the bases of the footings. Passive resistance may be calculated using a rectangular distribution of 1,500 psf; the upper one-foot of soil should be ignored unless it is confined by slabs or pavement. Frictional resistance should be computed using a base friction coefficient of 0.35. If a waterproofing system is used beneath the footings, the frictional resistance should be reduced to a value of 0.2. These values include a factor of safety of at least 1.5. The footing excavations should be free of standing water, debris, and disturbed materials prior to placing concrete. We should check the excavations prior to placement of reinforcing steel to confirm the exposed residual soil or bedrock is suitable to support the design bearing pressure. If loose soil or undesirable material is encountered in the excavations, it should be removed and the overexcavation backfilled with lean or structural concrete. Concrete Slab-On-Grade. The slab-on-grade floor should be supported on at least 12 inches of select fill placed as described above in the Site Preparation and Grading section. As a minimum, a moisture barrier should be installed beneath the slab-on-grade floor. The moisture barrier may be included as part of the select fill thickness. Atypical moisture prevention barrier includes a capillary moisture break consisting of at least a six-inch-thick layer of clean, free-draining gravel or crushed rock (1/2 to 3/a-inch gradation) overlain by a moisture-proof membrane at least 10 millimeters thick. The membrane should be covered with two inches of sand for protection against puncturing or tearing during construction and to aid in curing the concrete slab. If the previously compacted soil subgrade is disturbed during footing and utility excavation, the subgrade should be re-compacted to provide a firm, unyielding surface prior to placement of the capillary break material. The crushed rock and sand layers should conform to the gradation requirements presented in Table 2. TABLE 2 GRADATION REQUIREMENTS FOR CAPILLARY BREAK AND SAND SIEVE SIZE PERCENTAGE. PASSING SIEVE GRAVEL OR CRUSHED ROCK 1 inch 100 3/4 inch 30-75 1/2inch 5-10 3/flinch 0-2 SAND No. 4 100 No. 200 0-5 If water vapor moving through the slab is considered detrimental, in lieu of the moisture barrier, a waterproofing membrane should be installed. The membrane should consist of apre-applied, self-adhering high-density polyethylene (HDPE). Seismic Design. The buildings would be designed using the 1997 Uniform Building Code (UBC). For design in accordance with the 1997 UBC, Treadwell & Rollo recommend the following: • Seismic Zone Factor 4 • Soil profile Type Ss • Near Source Factors Na and N~ of 1.14 and 1.48, respectively. Flexible Pavement Design. The State of California flexible pavement design method was used to develop the recommended asphalt concrete pavement sections. The geotechnical engineers expect the final soil subgrade in asphalt-paved areas would generally consist of residual soil comprised of sandy clay. On the basis of laboratory test results of this soil, Treadwell & Rollo selected an R-value of 20 for design. If the existing subgrade would be raised in the paved areas, the fill material should have an equivalent or higher R-value than the native soil. Additional R-value tests should be performed on any proposed fill to verify its R-value. The pavement design may need to be revised if material with an adequate R-value cannot be found. Treadwell & Rollo presented design alternatives for three traffic indices (TI), 5.0, 5.5, and 6.0. For comparison, a TI of 5.0 assumes passenger car traffic with occasional trucks. Selection of the appropriate TI for design should be confirmed by the project civil engineer. If additional traffic indexes (TIs) are required for the project, the geotechnical engineers could assist the design team with the associated pavement recommendations. Table 3 presents flexible pavement section recommendations for the three TI values. TABLE 3 PAVEMENT SECTION DESIGN TRAFFIC INDEX ASPHALTIC CONCRETE. INCHES CLASS 2 AGGREGATE BASE R°= 78 INCHES 5.0 2.5 8.5 5.5 3.0 9.0 6.0 3.0 10.5 Pavement components should conform to the current Caltrans Standard Specifications. The upper six inches of the soil subgrade in pavement areas should be moisture-conditioned to above optimum moisture content and compacted to at least 95 percent relative compaction where either native soil or imported fill is exposed at subgrade level. Aggregate base should be compacted to at least 95 percent relative compaction. To prevent irrigation water from entering the pavement section, vertical curbs adjacent to landscaped areas should extend at least three inches into the underlying clay. Corrosivity Evaluation. Based on the resistivity measurements, 1,000 to 1,400 ohms- cm, the soil samples tested are classified as "corrosive". _ All- buried iron, steel, cast iron, ductile iron, galvanized steel and dielectric coated steel or iron placed at the site should be properly protected against corrosion depending upon the critical nature of the structures. In addition, all buried metallic pressure piping such as ductile iron firewater pipelines should be protected against corrosion. Both the chloride and sulfate ion concentrations, with ranges of none detected to 31 milligrams per kilogram (mg/kg) and 120 to 190 mg/kg, respectively, were determined to be insufficient to attack steel embedded in a concrete mortar coating. The hydrogen ion activity (pH) of the soil samples tested is not corrosive to buried iron, steel, mortar-coated steel and reinforced concrete structures. The redox potential of the soil samples tested indicates potentially "slightly corrosive" soils resulting from anaerobic soil conditions. Treadwell & Rollo should review the final foundation plans and specifications to check that they are in general conformance with the intent of their recommendations. They should observe fill placement and compaction, and perform field density test to check that adequate fill compaction has been achieved. During construction, the geotechnical engineers should observe the installation of the foundation system. Footing excavations should be checked to verify the foundation soil and rock are as anticipated. These observations would allow comparison of actual and anticipated soil conditions, check that the contractor's work conforms to the geotechnical aspects of the plans and specifications, and ensure that the building would perform as planned. These mitigation measures would reduce the impact of seismic ground shaking to people who would occupy the Cell Genesys Development to a level of less than significant with mitigation. ^ IMPACT 5: Use, Transport and Disposal of Hazardous Materials. Normal Cell Genesys operations at the Project site upon occupancy of the proposed buildings would involve use, transport and disposal of materials that would be considered hazardous if not handled appropriately. This would be a potentially signiftcant impact of the Project. ^ MITIGATION MEASURE 5: Adherence to Established Handling Protocols. The proposed Project would adhere to the Uniform Building Code's regulations applicable to office-type land uses. The use of potentially hazardous materials would follow established safety protocols, and materials to be disposed of would be collected in appropriate containers. These materials would then be transported away from the Project site by licensed waste collection agencies. This would reduce the impact of use, transport and disposal of hazardous materials to a level of less than significant with mitigation. ^ IMPACT 6: Asbestos Exposure. Excavation at the Project site during construction of the proposed buildings could expose construction workers to asbestos. This would be a potentially significant impact of the Project. ^ MITIGATION MEASURE 6: Use of Health and Safety Plan. Based on the results of asbestos testing, the bedrock that would be disturbed along the northern perimeter of the Project site should be removed, stockpiled appropriately and sampled and tested before off-site disposal. A health and safety plan should be written by the site excavation contractor with contingencies if more asbestos is encountered. The plan should include air and rock sampling and testing. This would reduce the impact of asbestos exposure to a level of less than significant with mitigation. ^ IMPACT 7: Increased Erosion During Construction. The soils at the Project site may be susceptible to erosion during construction activities when soils are disturbed. This represents a potentially significant impact associated with the proposed Project. ^ MITIGATION MEASURE 7: Erosion Control Measures. The applicant shall submit a Storm Water Pollution Prevention Plan (SWPPP) and an Erosion Control Plan to the City Engineer prior to the commencement of any grading or construction of the proposed Project. The SWPPP shall include storm water pollution control devices and filters to be installed to prevent pollutants from entering the City's storm drain system and San Francisco Bay. The Plan shall be subject to review and approval of the City Engineer and the City's Storm Water Coordinator. The Project applicant shall be responsible for ensuring that all contractors are aware of all storm water quality measures, and for the implementation of such measures. Failure to comply with the approved construction Best Management Practices (BMPs) will result in the issuance of correction notices, citations or a project stop order. Plans for the Project shall include erosion control measures to prevent soil, dirt and debris from entering the storm drain system, in accordance with the regulations outlined in the Association of Bay Area Governments Erosion and Sediment Control Handbook. Implementation of the above mitigation measures would reduce the Project's impact to a level of less than significant with mitigation. ^ IMPACT 8: Inconsistency with East of 101 Area Plan. The Project as proposed would be inconsistent with the following provision of East of 101 Area Plan policy DE-56: Parking Lot Trees: Cars should not be parked more than twelve in a row without a planting island that contains at least one tree. This inconsistency would be a potentially significant impact of the proposed Project. ^ MITIGATION MEASURE 8: Parking Lot Reconfiguration. The proposed Project parking lot shall be reconfigured in a way that conforms to all provisions of East of 101 Area Plan policy DE-56. This would reduce the impact to a level of less than significant with mitigation. ^ IMPACT 9: Construction Related Noise. Project construction would result in temporary short-term noise increases due to the operation of heavy equipment. This would represent a potentially significant impact associated with Project development. Construction noise sources range from about 82 to 90 dBA at 25 feet for most types of construction equipment, and slightly higher levels of about 94 to 97 dBA at 25 feet for certain types of earthmoving and impact equipment. ^ MITIGATION MEASURE 9: Limitation of Construction Hours/Noise Abatement. There are no existing noise-sensitive receptors in the project vicinity that would be affected by project-generated construction noise. However, neighboring businesses would be subjected to high noise levels during site preparation and construction. Although the highest noise levels would be generated by rock drills and pile drivers (which can generate noise peaks of approximately 98 and 101 dBA at 50 feet, respectively), such equipment would not be used for this project. If noise controls are installed on construction equipment, the noise levels could be reduced to 80 to 85 dBA at 25 feet, depending on the type of equipment. Assuming construction noise levels comply with the 90-dBA noise limit and hourly restrictions specified in the City Noise Ordinance, construction-related noise impacts could be reduced to a level of less than significant with mitigation. ^ IMPACT 10: Blocked Sight Lines. Access to the Project site would be provided via one driveway connection to Forbes Boulevard about 25 feet from the east end of the Project frontage and one driveway connection to Allerton Avenue about 25 feet from the south end of the Project frontage. At the Forbes Boulevard driveway intersection the sight line to the west to see eastbound traffic is about 450 feet, while the sight line to the east to see westbound traffic is greater than 500 feet. However, the height of the berm and landscaping in the two 75-foot-long raised medians just east of the proposed site driveway along Forbes Boulevard could partially block sight lines between drivers leaving the Project site and westbound traffic on Forbes Boulevard, particularly for cars riding low to the ground. This would be a potentially significant impact of the Project. ^ MITIGATION MEASURE 10: Berm Height Reduction. The height of the berm in the two median islands along Forbes Boulevard should be reduced just east of the proposed Project driveway. Landscaping should be replaced as required. This would reduce the impact of blocked sight lines to a level of less than significant with mitigation. ^ IMPACT 11: Forbes Boulevard Median. Figure 6 of the traffic analysis included as Appendix B shows that a 75 foot-long landscaped median is in place along Forbes Boulevard at the location of the proposed Project driveway. The driveway and/or the island's location would preclude direct left turn movements to/from the Project driveway and would result in a significant number of U-turns at either end of the island. This would create significant traffic safety and operational concerns as Project drivers would slow to conduct U-turns in the higher speed through travel lanes of Forbes Boulevard. In addition, the island's 12-foot width would not be great enough to provide refuge for the entire length of most U-turning vehicles. This would be a potentially significant impact of the Project. ^ MITIGATION MEASURE 11: Street Re-Configuration. The raised median along Forbes Boulevard at the location of the proposed Project driveway should be removed. In addition, a continuous two-way left turn lane should be striped that would extend easterly from the Project driveway to serve the existing driveway on the adjacent property about 50 feet to the east. This would reduce the impact to a level of less than significant with mitigation. APPENDIX B TRAFFIC ANALYSIS TRAFFIC IMPACT STUDY CELL GENESYS R&D OFFICE BUILDING IN SOUTH SAN FRANCISCO August 2, 2001 Prepared For: City of South San Francisco Prepared By: Crane Transportation Group 545 Burnett Avenue, Suite 101 San Francisco, California 94131 (415) 282-9656 I. INTRODUCTION This report details the circulation impacts due to the proposed 154,000-square-foot Cell Genesys biotechnology office complex to be located on the southeast corner of the Forbes Boulevazd/ Allerton Avenue intersection in South San Francisco. Existing, existing + approved development (Base Case) and Base Case + project AM and PM peak hour operating conditions have been evaluated at major intersections near the project site. In addition, safety and operations evaluation has been conducted at each proposed project driveway connection to Forbes Boulevard and Allerton Avenue. II. SUMMARY OF FINDINGS Both the Forbes Boulevazd/Allerton Avenue and Forbes Boulevazd/Eccles Avenue intersections aze currently operating at acceptable levels of service during AM and PM peak hour traffic conditions. Both intersections would maintain acceptable operation with the addition of traffic from approved local azea developments (Base Case conditions). This assumes programmed signalization of the Forbes Boulevazd/Eccles Avenue intersection by the end of 2002. The Forbes Boulevazd/Allerton Avenue intersection would not have Base Case volumes meeting peak hour signal wanrant criteria levels. 2. The proposed Cell Genesys project would be expected to generate 83 inbound and 17 outbound AM peak hour trips, with 14 inbound and 79 outbound PM peak hour trips. These projections assume no significant TDM program in operation. 3. All major intersections along Forbes Boulevazd neaz the project site would maintain acceptable AM and PM peak hour operation with the addition of project traffic to Base Case volumes. The Forbes Boulevazd/Allerton Avenue intersection would not have Base Case volumes increased to meet peak hour signal warrant criteria levels with the addition of project traffic. 4. The project's proposed Forbes Boulevard driveway would experience operational and safety concerns. An existing 75-foot-long raised median island would block direct left turn in and outbound access at the proposed driveway location. This would result in numerous U-turn movements at either end of the island by project traffic. In addition, berms and landscaping in two median islands along Forbes Boulevazd just east of the proposed driveway could restrict sight lines between westbound drivers on Forbes Boulevazd and drivers exiting the project site. No significant operational or safety concerns would be expected at the project's proposed Allerton Avenue driveway. 8/16/01 CTG Page 1 Cell Genesys 6. Recommended improvements aze as follows: A) Base Case (Without Project) Conditions: Provide a left turn deceleration lane on the westbound Forbes Boulevazd approach to Allerton Avenue. This would require removal of the 75-foot-long raised median that starts about 30 feet east of the Allerton Avenue intersection. B) Project Remove the raised median along Forbes Boulevazd at the location of the proposed project driveway. In addition, stripe a continuous two-way-left turn lane extending easterly from the project driveway to serve the existing driveway on the adjacent property (about 50 feet to the east). Reduce the height of the berms and landscaping in the two median islands along Forbes Boulevard just east of the proposed project driveway. Replace landscaping as required. III. SETTING This section describes the existing circulation system that will serve the proposed Cell Genesys project. A. ROADWAYS The project site is served directly by Forbes Boulevard and Allerton Avenue. Additional local area access is also provided by Eccles Avenue-see Figure 1. Each roadway is briefly described below while a schematic presentation of intersection approach lanes and intersection control are presented in Figure 2. Forbes Boulevard is a four-lane roadway running in a general east-west direction along the north side of the project site. Each travel lane is 12 feet wide. It has a raised landscaped median with median breaks at intersections and driveways. The posted speed limit is 35 miles per hour and on-street parking is prohibited (nor is there room for on-street parking within the existing lane widths). Forbes Boulevazd is all-way-stop controlled at Eccles Avenue, but is not signal or stop sign controlled on the approaches to Allerton Avenue. Left turn deceleration lanes aze not provided on the approaches to Allerton Avenue or driveways in the vicinity of the project site. Curb, gutter and sidewalk are provided along the north side of the street while curb and gutter only are provided on the south (project) side of the street. Allerton Avenue is a two-lane, 40-foot-wide roadway extending southerly from Forbes Boulevazd for about half a mile before ending at East Grand Avenue. The Allerton Avenue approaches to both Forbes Avenue and East Grand Avenue aze stop sign controlled while the 8/16/01 CTG Page 2 Cell Genesys posted speed limit is 30 miles per hour. Curb, gutter and sidewalk are provided along the west side of the street while curb and gutter only aze provided along the east (project) side of the street. Left turn lanes are not provided on the approach to any intersection or driveway. On- street parking is prohibited along both sides of the street in the vicinity of the project. Eccles Avenue is atwo-lane, 40-foot-wide roadway extending northerly from Forbes Boulevazd for about half a mile to a connection with Oyster Point Boulevazd. It has anal]-way-stop intersection with Forbes Boulevazd and a signalized intersection with Oyster Point Boulevazd. A single track industrial spur railroad line extends through the Eccles Avenue/Forbes Boulevazd intersection. B. VOLITMES Weekday AM and PM peak period (7:00-9:00 AM and 4:00-6:00 PM) vehicle, pedestrian and bicycle counts were conducted by Crane Transportation Group on June 27, 2001 at the Forbes Boulevard/Allerton Avenue and Forbes Boulevazd/Eccles Avenue intersections. The peak hours were determined to be 7:45 to 8:45 AM and 4:45to 5:45 PM. Resultant AM and PM peak hour traffic volumes aze presented in Figure 3. Only minor levels of pedestrians and bike riders were observed at either intersection during either survey period. During the two-hour AM peak period seven bike riders passed through both the Forbes Boulevazd/Allerton Avenue and Forbes Boulevard/Eccles Avenue intersections, while only one pedestrian crossed Forbes Boulevard at Allerton Avenue. During the two-hour PM peak period six bike riders passed through the Forbes Boulevazd/Allerton Avenue intersection while 13 bike riders passed through the Forbes BoulevazdlEccles Avenue intersection. Only one pedestrian crossed Forbes Boulevazd at Allerton Avenue during the PM peak period. C. INTERSECTION OPERATION 1. Analysis Methodology Signalized Intersections. Intersections, rather than roadway segments between intersections, aze almost always the capacity controlling locations for any circulation system. Signalized intersection operation is graded based upon two different scales. The first scale employs a grading system called Level of Service (LOS) which ranges from Level A, indicating uncongested flow and minimum delay to drivers, down to Level F, indicating significant congestion and delay on most or all intersection approaches. The Level of Service scale is also associated with an average vehicle delay tabulation (1994 Highway Capacity Manual [HCM] operations method) at each intersection. The vehicle delay designation allows a more detailed examination of the impacts of a particular project. Greater detail regarding the LOS/delay relationship is provided in the Appendix. Unsignalized Intersections. Unsignalized intersection operation is also typically graded using the Level of Service A through F scale. LOS ratings for all-way stop intersections aze determined using a methodology outlined in the 1994 update of the Highway Capacity Manual (TRB Circular 209). Under this methodology, all-way stop intersections receive one LOS designation reflecting operation of the entire intersection. Average vehicle delay values aze also 8/l6/0l CTG Page 3 Cell Genesys calculated. Intersections with side streets only stop sign controlled are also evaluated using the LOS and delay scales using a methodology outlined in the 1994 Highway Capacity Manual. However, unlike signalized or all-way stop analysis where the LOS and delay designations pertain to the entire intersection, in side street stop sign control analysis LOS and delay designations aze computed for stop sign controlled approaches or individual turn and through movements rather than for the entire intersection. The Appendix provides greater detail about unsignalized analysis methodologies. 2. Standards The City of South San Francisco considers Level of Service D (LOS D) to be the poorest acceptable operation for signalized and all-way-stop intersections and LOS E to be the poorest acceptable operation for unsignalized city street intersection turn movements. The City has no standazds for turn movements from private driveways. 3. Existing Operating Conditions Table 1 shows that currently the all-way-stop Forbes Boulevazd/Eccles Avenue intersection is operating at acceptable levels of service during both commute periods (LOS C during both the AM and PM peak traffic hours). At the Forbes Boulevazd/Allerton Avenue intersection, movements from the stop sign controlled Allerton Avenue approach aze also operating acceptably during both commute periods (LOS B during both the AM and PM peak traffic hours). D. INTERSECTION SIGNALIZATION REQUIREMENTS Traffic signals are used to provide an orderly flow of traffic through an intersection. Many times they aze needed to offer side street traffic an opportunity to access a major road where high volumes and/or high vehicle speeds block crossing or turn movements. They do not, however, increase the capacity of an intersection (i.e., increase the overall intersection's ability to accommodate additional vehicles) and, in fact, often slightly reduce the number of total vehicles that can pass through an intersection in a given period of time. Signals can also cause an increase in traffic accidents if installed at inappropriate locations. There are 11 possible tests for determining whether a traffic signal should be considered for installation. These tests, called "warrants", consider criteria such as actual traffic volume, pedestrian volume, presence of school children, and accident history. Usually, two or more warrants must be met before a signal is installed. In this report, the test for Peak Hour Volumes (Warrant #11) has been applied. When Warrant 11 is met there is a strong indication that a detailed signal warrant analysis covering all possible warrants is appropriate. These rigorous analyses are described in Chapter 9 of the Caltrans Traffic.Manual_ while Warrant 11 is presented in the Appendix of this report. Currently, neither the Forbes Boulevazd/Allerton Avenue nor the Forbes Boulevazd/Eccles Avenue intersections have AM or PM peak hour volumes meeting peak hour signal warrant criteria levels. 8/16/01 CTG Page 4 Cell Genesys 8/16/01 CTG Page 5 Cell Genesys E. OBSERVED SAFETY CONCERNS The Forbes Boulevazd pavement is deteriorated in several locations. In addition, uneven pavement covering past trenching in the eastbound and westbound curb travel lanes creates uncomfortable driving conditions and a safety hazazd for bicycle riders. The lack of an exclusive left turn lane on the Forbes Boulevazd westbound approach to Allerton Avenue increases the chances for rear-end accidents between a vehicle slowing or stopped waiting to turn left and a higher speed through vehicle. The wide median break along Forbes Boulevard at this location does, however, provide an informal storage (refuge) azea for turning vehicles. F. PLANNED IMPROVEMENTS Forbes Boulevard is planned to be repaved by the end of August, 2001' and the Forbes Boulevazd/Eccles Avenue intersection is programmed to be signalized by the end of 2002.2 IV. EXISTING + APPROVED DEVELOPMENT (BASE CASE) OPERATING CONDITIONS A. VOLUMES AM and PM peak hour trip generation and distribution projections were developed for currently approved or under construction developments in South San Francisco to the east of the U.S.101 freeway. Approved projects and their expected trip generation aze presented in Table 2. Both trip rates and regional distribution patterns applied to each approved development aze contained in the Apri12001 Draft Supplemental EIR for the South San Francisco General Plan Amendment and Transportation Demand Management Ordinance. At the request of City Planning staff, peak hour trip generation from each approved project has been reduced by 35% to reflect implementation of Transportation Demand Management (TDM) measures.3 Resultant existing + approved development (Base Case) AM and PM peak hour volumes aze presented in Figure 4. B. INTERSECTION OPERATION ' Mr. Steve Carlson, South San Francisco Planning Department. 2 Mr. Richard Harmon, South San Francisco Public Works Department. 3 Measures could include (but not be limited to) provision of bicycle lockers and racks as well as showers and changing rooms, operation of a shuttle to BART and Caltrain, subsidizing transit tickets for employees, creation of preferential pazking for caz and vanpoolers, implementation of a vanpool program, facilitating employee telecommuting, flexible work hours, provision of child caze services, etc. 8/16/01 CTG Page 6 Cell Genesys For Base Case analysis purposes, the Forbes Boulevazd/Eccles Avenue intersection has been assumed signalized. Table 1 shows that a signalized Forbes Boulevazd/Eccles Avenue intersection would operate at good levels of service with Base Case volumes (LOS A during both the AM and PM peak traffic hours). At the Forbes Boulevazd/Allerton Avenue intersection, the stop sign controlled Allerton Avenue approach would continue to operate at acceptable levels of service during both commute periods (LOS B during both the AM and PM peak traffic hours). Volumes at this location would not be increased to meet peak hour signal warrant criteria levels with the addition of approved development traffic. V. PROJECT IMPACTS A. TRIP GENERATION Table 3 shows that the Cell Genesys 154,000 squaze feet of reseazch and development (in two buildings) would be expected to generate 83 inbound and 17 outbound trips during the AM peak hour, with 14 inbound and 79 outbound trips during the PM peak hour. These projections are based upon trip rates from existing research and development facilities in the East of 101 azea and do not include any significant reduction in peak hour trip generation due to TDM measures. Should Cell Genesys develop a significant TDM program and reach the City's desired goal of 35 percent reduction in peak hour traffic, trip generation would be reduced to 54 inbound and 11 outbound trips during the AM peak hour with 9 inbound and 52 outbound trips during the PM peak hour. B. TRIP DISTRIBUTION Project traffic was distributed to the subregional roadway network based upon East of 101 development traffic patterns contained in the Apri12001 Draft SEIR for the South San Francisco General Plan Amendment and Transportation Demand Ordinance. Overall, about 62 percent of project traffic should be destined to/from south and southwest of the site, with 38 percent destined to/from the north and northwest. However, it is likely that some project drivers destined to/from the south on the U.S. 101 freeway would choose to access the freeway via Oyster Point Boulevazd, which is north of the site. Project traffic is shown distributed to the local roadway network with Base Case volumes in Figure 4 for AM and PM peak hour conditions, while Figure 5 presents expected project traffic turn movements at each of the site driveways. C. INTERSECTION IMPACTS Table 1 shows that a signalized Forbes Boulevazd/Eccles Avenue intersection would continue to operate at good levels of service with Base Case + project volumes (LOS A during both the AM and PM peak traffic hours). Project traffic would increase average vehicle delay about two- tenths of a second during the AM peak hour and not produce a measurable change in delay during the PM peak hour. At the Forbes Boulevazd/Allerton Avenue intersection, the stop sign controlled Allerton Avenue approach would continue to operate at acceptable levels of service during both commute periods (LOS B during the AM peak hour and changing from LOS B to an acceptable LOS C during the PM peak hour). The Forbes Boulevazd/Allerton Avenue 8/16/0] CTG Page 7 Cell Genesys intersection would not have volumes increased to meet peak hour signal warrant criteria levels with the addition of project traffic to Base Case volumes. D. ACCESS IMPACTS Sight Lines Access to the project site would be provided via one driveway connection to Forbes Boulevard (about 25 feet from the east end of the project frontage) and one driveway connection to Allerton Avenue (about 25 feet from the south end of the project frontage). At the Forbes Boulevard driveway intersection the sight line to the west (to see eastbound traffic) is about 450 feet, while the sight line to the east (to see westbound traffic) is greater than 500 feet. However, the height of the berm and landscaping in the two (75-foot-long) raised medians just east of the proposed site driveway along Forbes Boulevard could partially block sight lines between drivers leaving the project site and westbound traffic on Forbes Boulevard (particularly for cars riding low to the ground). This would create traffic safety concerns. At the Allerton Avenue driveway, the sight line to the north extends about 375 feet to the Forbes Boulevard intersection, while the sight line to the south extends more than 500 feet. Observed vehicle speeds on Forbes Boulevard ranged as high as 45 miles per hour. An acceptable stopping sight distance at this speed is 360 feet.4 Along Allerton Avenue, observed speeds ranged as high as 40 miles per hour. An acceptable stopping sight distance at this speed is 305 feet. Therefore, sight lines at both driveways should be adequate, with the concern detailed above that the height of the two raised medians along Forbes Boulevard just east of the project driveway could partially block sight lines for low riding vehicles. 2. Forbes Boulevard Median Figure 6 shows that a 75-foot-long landscaped median is in place along Forbes Boulevard at the location of the proposed project driveway. The driveway and/or the island's location would preclude direct left turn movements to/from the project driveway and would result in a significant number of U-turns at either end of the island. This would create significant traffic safety and operational concerns as project drivers would be slowing to conduct U-turns in the higher speed through travel lanes of Forbes Boulevard. Also, the island's 12-foot width would not be great enough to provide refuge for the entire length of most U-turning vehicles. VI. RECOMMENDED IMPROVEMENTS A. BASE CASE (WITHOUT PROJECT) CONDITIONS 4 A Policy on Geometric Design of Highways and Streets, Fourth Edition, AASHTO, 2001. 8/16/01 CTG Page 8 Cell Genesys • Provide a left turn deceleration lane on the westbound Forbes Boulevard approach to Allerton Avenue. This would require removal of the 75-foot-long raised median that starts about 30 feet east of the Allerton Avenue intersection. B. PROJECT Remove the raised median along Forbes Boulevard at the location of the proposed project driveway. In addition, stripe a continuous two-way-left turn lane extending easterly from the project driveway to serve the existing driveway on the adjacent property (about 50 feet to the east). Reduce the height of the berms and landscaping in the two median islands along Forbes Boulevard just east of the proposed project driveway. Replace landscaping as required. 8/16/01 CTG Page 9 Cell Genesys Not To Scale' ~~ NORTH Cell Genesys Tragic Study --, Figure 1 Area Map CRANE TRANSPORTATION GROUP Not To Scale ~O NORTH Q V W Parking Lot '~~ -r Forbes Blvd r ~<< Parking :~:<>:<::;:«:::: ~ Lot ........P.R~OJECT Q SITE -r =Stop Sign Q Cell Genesys Traffic Study --~ Figure 2 Existing Lane Geometrics and Intersection Control CRANE TRANSPORTATION GROUP ~ Not/To~Sple V Nonni ~m Q '~ 50 60 0 103 ~- 140 0 130 ~ ,1 710-~ 0 0 0 1 ~. Forbes Blvd '~ s 3 0 0 <--- 130 45 16~ -__ 540 -~ 20 O 46 PROJECT SITE AM Peak Hour (7:45-8:45) Q ~' W '~ 215 130 0 45 E- 520 ~- 1 Forbes Blvd '~ 7 11 1 2 F- 430 ~~~ ~ 45 _ 90 ,' ~~~ 235--?- q 6 0 0 PM Peak Hour (4:45-5:45) Cell Ger~esys Traffic Study --~ Figure 3 Existing Volumes AM & PM Peak Hour -June 27, 2001 CRANE TRANSPORTATION GROUP Not/To~Scale V NORTH ~~ Q ~I U W ® '~ 56 ® '~ 8 67 0 147 E- 1 ~ ® 3 0 0 ~- 139 0 Forbes Blvd ~ ~ ~ ~ 8502 130 ~~~ ®0 745-~ 0 0 0 1 ~. AM Peak Hour (7:45-8:45) `~~~~~~~ =Project Site `: 3 -Base Case (Existing + Approved Projects) 03 .Project Increment (Without TDM Program) m Q ~l 2 '~ 258 19 132 0 1409 E- 555 18 I ~ 1 Fnrhnc Rlvr~ 95 ~ ~~~ 03 240 4 6 0 0 ~. PM Peak Hour (4:45-5:45) Cell Genesys Traffic Study 16~ O ~ ~ ~ 14 576 _~ . 27 0 56 ,_.:. 14 77 ~, •,4® PROJECT SITE '~ 7 T 1 l 1 2 ~- 467 19 ~~~ ~ 49 3 ~ ~ `~ 3 201 ~• ~ ~ ~ `' :> 77 0 101'•.:: 28 ~, _> 18 02 l{ e t~.PROJ~EC r SITE -~ Figure 4 Base Case and Project Volumes AM & PM Peak Hour CRANE TRANSPORTATION GROUP Q O •~ 402 F- 4 20 E- 4 ~ Forbes Blvd I ~ 2 0_ ...: 13 20 -~ `~;~~~, 09 14 ,j 4 w...ti :~w~.... _ Project Site 3 .Without TDM Program ~ . 35% reduction due to TDM Program AM Peak Hour (7:45-8:45) ~m Q ~I U W tL 1s t2 (~ t-- 18 12 20 3 -~ ~ 1s 12 Forbes Blvd Project Site 3 =Without TDM Program Q . 35% reduction due to TDM Program PM Peak Hour (4:45-5:45) Cell Genesys Traffic Study Not To Scale ~O NORTH -~ Figure 5 Project Trip Generation ~ AM & PM Peak Hour CRANE TRANSPORTATION GROUP Not To Scale ~~ NORTH ~ ~ 75~ ~. ~ ~ f- 75' -~ ~ ~ •--- 75' ' ~ Q 0 m Q I I ~ ~ ~ I _.:>:; Forbes Blvd 285' PROJECT SITE = Raised Median Islands Cell Genesys Traffic Study 28y '~ If -- 25 125 Proposed ' ~ to Existing Driveway Project ~m~ Driveway I~ 0 I= .Q -' Figure 6 Existing Medians Along Project's Forbes Boulevard Frontage CRANE TRANSPORTATION GROUP J Table 1 INTERSECTION LEVEL OF SERVICE AM PEAK HOUR EXISTING + APPROVED DEVELOPMENT BASE CASE + INTERSECTION EXISTING BASE CASE PROJECT* Forbes Blvd./Eccles Ave. C-17.2~'~ A-9.5~2~ A-9.7 Forbes Blvd./Allerton Ave. B-7.4~3~ B-9.4 B-9.9 PM PEAK AniTR EXISTING + APPROVED DEVELOPMENT BASE CASE + INTERSECTION EXISTING ASE CASE PROJECT* Forbes Blvd./Eccles Ave. C-18.4"~ A-8.9~Z~ A-8.9 Forbes Blvd./Allerton Ave. B-6.6'3 B-9.2 C-11.2 * Assumes no reduced project trip generation due to TDM measwes. ~'~ All way stop level of service-average vehicle delay in seconds. 'Z~ Signalized level ofservice-average vehicle delay in seconds. (3) Unsignalized level of service-average vehicle delay in seconds. Allerton Avenue stop sign controlled approach to Forbes Boulevard. 1994 Highway Capacity Manual analysis methodology. Source: Crane Transportation Group Table 2 TRIP GENERATION APPROVED PROJECTS THAT MAY CONTRIBUTE TRAFFIC TO FORBES BOULEVARD, ALLERTON AVENUE AND ECCLES AVENUE NEAR THE CELL GENESYS PROJECT AM PEAK HOUR TRIPS PM PEAK HOUR TRIPS INBOUND OUTBOUND INBOUND OUTBOUND PROJECT SIZE RATE VOL RATE VOL RATE VOL RATE VOL Genentech Bldg. 6 120,000 SQ.FT. .54 65 .11 13 .09 11 .51 61 (East end Forbes Blvd.) R&D Genentech Bldg. 7 90,000 SQ.FT. .54 49 .11 10 .09 8 .51 46 (East end Forbes Blvd.) R&D Founders Research Center 287,444 SQ.FT. .54 155 .11 32 .09 26 .51 147 (East end Forbes Blvd.) R&D Gateway Tech Center Bldg. 3 50,000 SQ.FT. .54 27 .11 6 .09 5 .51 26 (Forbes Blvd. near East Grand) R&D Sand Hill Property Company 200,000 SQ.FT. .92 184 .13 26 .16 32 .80 160 (345 East Gtand Ave.) Office Britannia East 785,000 SQ.FT. .72 565 .13 102 .12 94 .66 518 (East end of East Grand Ave.) OfficelR&D 8,000 SQ.FT. 6.7 54 6.0 48 6.2 50 7.0 56 Child Care 5,000 SQ.FT. .14 1 .16 ] 2.62 13 1.68 9 Fitness Center 5,000 SQ.FT. .60 3 .21 1 5.02 25 2.47 12 Restaurant 3,000 SQ.FT. .72 2 .48 2 1.8 6 1.8 6 Retail Peak hour trip rates do not include any reduction due to TDM measures. Project List Source: City of South San Francisco Planning Department. Trip Rate Source: Draft SEIR South San Francisco General Plan Amendment and Transportation Demand Management Ordinance, April 2001. Compiled b}~• Crane Transportation Group Table 3 TRIP GENERATION CELL GENESYS AM PEAK HOUR TRIPS PM PEAK HOUR TRII'S INBOUND OUTBOUND INBOUND OUTBOUND USE SIZE RATE VOL RATE VOL RATE VOL RATE VOL Biotechnology Office 154,000 SQ.FT. .54 83 .11 17 .09 14 .51 79 With 35% Reduction in Peak Hour Trips Due to TDM Pro m 54 11 9 52 Trip Rate Sowce: Draft SEIR, South San Francisco General Plan Amendment and Transportation Demand Management Ordinance, April 2001. Compiled by: Crane Transportation Group DESCRIPTION OF LEVEL OF SERVICE FOR MINOR MOVEMENTS AT UNSIGNALIZED INTERSECTIONS Level of Service Average Total Delay (seconds per vehicle) A s5 g > 5 and s 10 C > 10 and < ZO D > 20 ands 30 g > 30 ands 45 F > 45 Total delay is defined as the total elapsed time from when a vehicle stops at the end of the queue until the vehicle departs from the stop line; this time includes the time required for the vehicle to travel from the last-in-queue position to the first-in-queue position. Source: 1994 Highway Capacity Manual ALL-WAY STOP LEVEL OF SERVICE -AVERAGE DELAY RELATIONSHIP Level of Service Average Total Delay (seconds per vehicle) A s5 B > 5 and s 10 C > 10 and < 20 D > 20 ands 30 g > 30 ands 45 p > 45 Total delay is defined as the total elapsed time from when a vehicle stops at the end of the queue until the vehicle departs from the stop line; this time includes the time required for the vehicle to travel from the last-in-queue position to the first-in-queue position. Source: 1994 Highway Capacity Manual SIGNALIZED INTERSECTION LEVEL OF SERVICE DEFINTfIONS Level of Service Description p Very low delay, less than 5.0 seconds per vehicle. Progression is extremely favorable, and most vehicles arrive during the green phase. Most vehicles do not stop at all. Short cycle lengths contribute to low delay. B Delay in the range of 5.1 to 15.0 seconds per vehicle. Good progression and/or short cycle lengths. More vehicles stop causing higher levels of average delay. C Delay in the range of 15.1 to 25.0 seconds per vehicle. Fair progression and/or longer cycle lengths. Individual cycle failures, resulting in drivers having to wait through more than one red signal indication, begin to appear. The number of vehicles stopping is significant, although many still pass through the intersection without stopping. D Delay in the range of 25.1 to 40.0 seconds per vehicle. The influence of congestion becomes more noticeable. Unfavorable progression, long cycle lengths, or high volumes. Many vehicles stop, the proportion of vehicles not stopping declines. Individual cycle failures noticeable. E Delay in the range of 40.1 to 60.0 seconds per vehicle. The limit of acceptable delay. Poor progression, long cycle lengths, and high volumes. Individual cycle failures are frequent. F Delay in excess of 60.0 seconds per vehicle. Unacceptable to most drivers. Oversaturation, arrival flow rates exceed the capacity of the intersection. Many individual cycle failures. Poor progression and long cycle lengths. Source: 1994 Highway Capacity Manual 9.14 TRAFFIC SIGNALS AND LIGHTING Traffic Manual s-»s~ Figure 9-8 PEAK HOUR VOLUME WARRANT (Urban Areas) 600 x '. 500 x F- U p 400 y a a o W 300 z ~ ~ ~ 0 200 x c~ = 100 0 2 OR MORE LANES (MAJOR) & 2 OR MORE LANES (MINOR) I I I ~ I ~}-2 OR MORE LANES (MAJOR) & 1 LANE (MINOR) I ~ I OR 1 LANE (MAJOR) & 2 OR MORE LANES (MINOR) 1 LANE (MAJOR) & 1 LANE (MINOR) 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 MAJOR STREET -TOTAL OF BOTH APPROACHES -VPH 4 * NOTE: 150 VPH APPLIES AS THE LOWER THRESHOLD VOLUME FOR A MINOR STREET APPROACH WITH TWO OR MORE LANES AND 100 VPH APPLIES AS THE LOWER THRESHOLD VOWME FOR A MINOR STREET APPROACHING WITH ONE LANE. ~; This Report is intended for presentation and use in its entirety, together with all of its supporting exhibits, schedules, and appendices. 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