4. Environmental Setting, Impacts, Standard Conditions of Approval, and Mitigation Measures

4.8 Geology, Soils, and Geohazards

This section describes geologic and seismic conditions in the project vicinity to provide relevant background information of the physical characteristics of the project site with respect to soils and potential geologic hazards. The following information is compiled from geologic maps and reports available from the City of Oakland, the California Geological Survey (CGS; formerly California Division of Mines and Geology), the ABAG, two geotechnical reports prepared by Geomatrix in 2008, and a third geotechnical report prepared by AMEC Geomatrix in 2009.

This section identifies any potentially significant geologic impacts and, if necessary, appropriate mitigation measures or standard conditions of approval. Pursuant to the City’s amendment to the Oakland General Plan (City of Oakland, 2005), as well as Section 15358(b) of the CEQA Guidelines, mitigation measures are proposed only to address physical impacts that may result from the project.

4.8.1 Environmental Setting The project site is situated within the Coast Ranges geomorphic province of California. The Coast Ranges is the largest of the state’s geomorphic provinces extending approximately 400 miles from the Klamath Mountains (near northern Humboldt County) to the Santa Ynez River in Santa Barbara County. The province lies between the Pacific Ocean and the Great Valley (Sacramento and San Joaquin valleys) provinces and is characterized by a series of northwest trending mountain ridges and valleys, running generally parallel to the San Andreas Fault zone. These mountain ridges and valleys have been formed by tectonic forces that compressed ancient sedimentary deposits over the course of millions of years.

San Francisco Bay is located in a broad depression in the Franciscan bedrock resulting from an east-west expansion between the San Andreas and the Hayward fault systems. The bedrock surface can be found at elevations of 200 to 2,000 feet below mean sea level across the Bay Area. Sedimentary deposits that overlie the Franciscan bedrock originated from millions of years of erosion, deposition, and changes in sea level. Geologists categorize these sedimentary deposits into geologic formations based on the period of deposition and material type, as described below for the San Francisco Bay region.

• The Alameda Formation is the deepest and oldest of these sedimentary deposits and consists of a mixture of clay, silt, sand, gravel, and some shells with predominantly silt and clay sediments surrounding discontinuous layers of sand and gravel;

• Overlying the Alameda Formation is the San Antonio Formation, which consists of sandy clays, gravelly clays, clayey sands and gravels with interbedded silty clay deposits.

• Younger alluvial deposits once referred to as the Temescal Formation are deposited on top of the San Antonio and consist of sandy clays, clayey sands, sands and gravels. The source material for these alluvial deposits comes from the Berkeley Hills.

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The geotechnical report conducted for the project site describe the subsurface conditions of the site as thick alluvial sediments (approximately 325 feet thick) overlying Franciscan Complex sedimentary bedrock units (Geomatrix, 2008). The alluvial materials consist primarily of stiff clays interbedded with dense silty sands and gravel lenses (Geomatrix, 2008).

Seismicity Seismic hazards include those hazards that could reasonably be expected to occur in the area during a major earthquake on any of the active faults in the region. Some hazards can be more severe than others, depending on the location, underlying materials, and level of ground shaking. The project site, like the entire Bay Area, lies within an area that contains many active and potentially active faults and is considered to be an area of high seismic activity.1 The USGS Working Group on California Earthquake Probabilities evaluated the probability of one or more earthquakes of Richter magnitude 6.7 or higher occurring in the San Francisco Bay Area within the next 30 years (USGS, 2008).2 The result of the evaluation indicated a 63 percent likelihood that such an earthquake event will occur in the Bay Area between 2007 and 2037 (USGS, 2008).

Ground movement during an earthquake can vary depending on the overall magnitude, distance to the fault, focus of earthquake energy, and type of geologic material. The composition of underlying soils, even those relatively distant from faults, can intensify ground shaking. For this reason, earthquake intensities are also measured in terms of their observed effects at a given locality. The Modified Mercalli (MM) intensity scale (Table 4.8-1) is commonly used to measure earthquake damage due to ground shaking. The MM values for intensity range from I (earthquake not felt) to XII (damage nearly total), and intensities ranging from IV to X can cause moderate to significant structural damage.3 The intensities of an earthquake will vary over the region of a fault and generally decrease with distance from the epicenter of the earthquake.

According to the Association of Bay Area Governments (ABAG) Shaking Intensity Maps and Information, the project site is located in an area subject to “moderate” ground shaking (Modified Mercalli Intensity VI) from earthquakes along the entire San Andreas (similar to the 1906 Earthquake), and “strong” ground shaking (Modified Mercalli Intensity VIII) from the Northern and Southern segments of the Hayward Fault (ABAG, 2009c).

1 An “active” fault is defined by the State of California as a fault that has had surface displacement within Holocene time (approximately the last 11,000 years). A “potentially active” fault is defined as a fault that has shown evidence of surface displacement during the Quaternary (last 1.6 million years), unless direct geologic evidence demonstrates inactivity for all of the Holocene or longer. This definition does not, of course, mean that faults lacking evidence of surface displacement are necessarily inactive. “Sufficiently active” is also used to describe a fault if there is some evidence that Holocene displacement occurred on one or more of its segments or branches (Hart, 1997). 2 Richter magnitude is a measure of the size of an earthquake as recorded by a seismograph. Richter magnitudes vary logarithmically, with each whole number step representing a ten-fold increase in the amplitude of the recorded seismic waves. Earthquake magnitudes are also measured by their Moment Magnitude (Mw) which is related to the physical characteristics of a fault including the rigidity of the rock, the size of fault rupture, and movement or displacement across a fault. 3 The damage level represents the estimated overall damage that will occur for various MM intensity levels. Damage, however, is not uniform, as the age, material, type, method of construction, size, and shape of a building all affect its performance.

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TABLE 4.8-1 MODIFIED MERCALLI INTENSITY SCALE

Average Peak Intensity Acceleration Value Intensity Description (% ga)

I Not felt except by a very few persons under especially favorable circumstances. < 0. 17 g

II Felt only by a few persons at rest, especially on upper floors on buildings. Delicately 0.17-1.4 g suspended objects may swing.

III Felt noticeably indoors, especially on upper floors of buildings, but many people do 0.17-1.4 g not recognize it as an earthquake. Standing motor cars may rock slightly, vibration similar to a passing truck. Duration estimated.

IV During the day felt indoors by many, outdoors by few. At night, some awakened. 1.4–3.9g Dishes, windows, doors disturbed; walls make cracking sound. Sensation like heavy truck striking building. Standing motor cars rocked noticeably.

V Felt by nearly everyone, many awakened. Some dishes and windows broken; a few 3.5 – 9.2 g instances of cracked plaster; unstable objects overturned. Disturbances of trees, poles may be noticed. Pendulum clocks may stop.

VI Felt by all, many frightened and run outdoors. Some heavy furniture moved; and fallen 9.2 – 18 g plaster or damaged chimneys. Damage slight.

VII Everybody runs outdoors. Damage negligible in buildings of good design and 18 – 34 g construction; slight to moderate in well-built ordinary structures; considerable in poorly built or badly designed structures; some chimneys broken. Noticed by persons driving motor cars.

VIII Damage slight in specially designed structures; considerable in ordinary substantial 34 – 65 g buildings, with partial collapse; great in poorly built structures. Panel walls thrown out of frame structures. Fall of chimneys, factory stacks, columns, monuments, walls. Heavy furniture overturned. Sand and mud ejected in small amounts. Changes in well water. Persons driving motor cars disturbed.

IX Damage considerable in specially designed structures; well-designed frame structures 65 – 124 g thrown out of plumb; great in substantial buildings, with partial collapse. Buildings shifted off foundations. Ground cracked conspicuously. Underground pipes broken.

X Some well-built wooden structures destroyed; most masonry and frame structures > 124 g destroyed with foundations; ground badly cracked. Rails bent. Landslides considerable from riverbanks and steep slopes. Shifted sand and mud. Water splashed (slopped) over banks.

XI Few, if any, (masonry) structures remain standing. Bridges destroyed. Broad fissures > 1.24 g in ground. Underground pipelines completely out of service. Earth slumps and land slips in soft ground. Rails bent greatly.

XII Damage total. Practically all works of construction are damaged greatly or destroyed. > 1.24 g Waves seen on ground surface. Lines of sight and level are distorted. Objects are thrown upward into the air.

a g (gravity) = 980 centimeters per second squared. 1.0 g of acceleration is a rate of increase in speed equivalent to a car traveling 328 feet from rest in 4.5 seconds.

SOURCE: (ABAG, 2003)

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The project area is not in an Alquist-Priolo Earthquake Fault Zone4, and no known active fault exists on or in the project area boundaries. The closest active fault is the Hayward-Rodgers Creek fault approximately 3 miles east of the project area (Jennings, 1994). Like the entire Bay Area, the project site is subject to ground shaking in the event of an earthquake on the regional faults.

Regional Faults The San Andreas, Hayward-Rodgers Creek, and Calaveras faults pose the greatest threat of significant damage in the Bay Area according to the USGS Working Group (USGS, 2008). These three faults exhibit strike-slip orientation and have experienced movement within the last 150 years (see Table 4.8-2).5 Other principal faults capable of producing significant ground shaking in the Bay Area include the San Gregorio, Concord-Green Valley and the Marsh Creek-Greenville faults. These faults are all considered active. Many other potentially active and inactive faults are also located throughout the Bay Area. Considerable seismic events can occur on faults with a long period of inactivity, although it is generally considered less likely. Occasionally, faults classified as inactive can exhibit secondary movement during a major event on another active fault.

TABLE 4.8-2 ACTIVE FAULTS IN THE PROJECT SITE VICINITY

Maximum Moment Distance and Magnitude Direction from Recency of Fault Historical Earthquake Fault Project Movement Classificationa Seismicityb (Mw)c

Historic (1868 M 6.8, 1868 Hayward 2.4 miles east Active 7.3 rupture) Many

Historic (1861 M 5.6–M 6.4, 1861 Calaveras 21 miles east Active 6.9 1911, 1984) M 6.2, 1911, 1984 Concord- 18 miles east Historic (1955) Active Historic active creep 6.7 Green Valley M 7.1, 1989

Historic (1906; M 8.25, 1906 San Andreas 15 miles west Active 7.9 1989 ruptures) M 7.0, 1838 Many

a See footnote 1. b Richter magnitude (M) and year for recent and/or large events. The Richter magnitude scale reflects the maximum amplitude of a particular type of seismic wave. c Moment Magnitude (Mw) is related to the physical size of a fault rupture and movement across a fault. Moment magnitude provides a physically meaningful measure of the size of a faulting event (CGS, 2002). The Maximum Moment Magnitude Earthquake, derived from the joint CGS/USGS Probabilistic Seismic Hazard Assessment for the State of California, 1996 (Peterson, 1996).

SOURCES: (1) Hart, 1997; (2) Jennings, 1994; (3) Peterson, 1996; (4) USGS, 2003; (5) Geomatrix, 2008.

4 An Alquist-Priolo Earthquake Fault Zone is an established regulatory zone around the surface traces of active faults. Local agencies must regulate most development projects within the zones. 5 A strike-slip fault is a fault in which movement is horizontal, parallel to the strike of the fault plane.

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Hayward Fault The Hayward Fault Zone is the southern extension of a fracture zone that includes the Rodgers Creek fault (north of San Pablo Bay), the Healdsburg fault (Sonoma County), and the Maacama fault (Mendocino County). The Hayward fault trends to the northwest within the East Bay, extending from San Pablo Bay in Richmond, 60 miles south to east San José. The Hayward fault in San José converges with the Calaveras fault, a similar type fault that extends north to Suisun Bay. The Hayward fault is designated by the Alquist-Priolo Earthquake Fault Zoning Act as an active fault.

A characteristic feature of the Hayward fault is its well-expressed and relatively consistent fault creep. Although large earthquakes on the Hayward fault have been rare since 1868, slow fault creep has continued to occur and has caused measurable offset. Fault creep on the East Bay segment of the Hayward fault is estimated at 9 millimeters per year (Peterson, 1996). However, a large earthquake could occur on the Hayward fault with an estimated moment magnitude (Mw) of about Mw 7.3. The USGS Working Group on California Earthquake Probabilities includes the Hayward–Rodgers Creek Fault Systems in the list of those faults that have the highest probability of generating earthquakes of magnitude (M) 6.7 or greater in the Bay Area (USGS, 2008).

Calaveras Fault The Calaveras fault is a major right-lateral strike-slip fault that has been active during the last 11,000 years. The Calaveras fault is located in the eastern San Francisco Bay region and generally trends along the eastern side of the East Bay Hills, west of San Ramon Valley, and extends into the western Diablo Range, and eventually joins the San Andreas Fault Zone south of Hollister. The northern extent of the fault zone is somewhat conjectural and could be linked with the Concord fault.

The Calaveras fault has been the source of numerous moderate magnitude earthquakes, and the probability of a large earthquake (greater than M6.7) is much lower than on the San Andreas or Hayward faults (USGS, 2008). However, this fault is considered capable of generating earthquakes with Mw 6.9.

Concord-Green Valley The Concord and Green Valley faults are part of the larger San Andreas Fault system. The Concord fault extends from the northwestern slope of Mt. Diablo north to Suisun Bay, where the Green Valley fault is generally thought to be connected to the Concord fault and continues north to Wooden Valley in Napa County. Several site-specific studies on these faults have been conducted in compliance with the Alquist-Priolo Earthquake Fault Zoning Act, and they report the most recent displacement on these faults between 2,600 and 2,700 years ago in the late Holocene.

San Andreas Fault The San Andreas Fault Zone is a major structural feature that forms at the boundary between the North American and Pacific tectonic plates, extending from the Salton Sea in Southern California near the border with Mexico to north of Point Arena, where the fault trace extends out into the Pacific Ocean. The main trace of the San Andreas fault runs through the Bay Area and trends northwest through the Santa Cruz Mountains along the eastern side of the San Francisco

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Peninsula. As the principal strike-slip boundary between the Pacific plate to the west and the North American plate to the east, the San Andreas is often a highly visible topographic feature, such as between Pacifica and San Mateo, where Crystal Springs Reservoir and San Andreas Lake clearly mark the rupture zone.

Seismic Hazards

Ground Shaking Strong ground shaking from a major earthquake could affect the project site during the next 30 years. An earthquake on any one of the active faults (listed in Table 4.8-2) could potentially produce a range of ground shaking intensities at the project site. Ground shaking may affect areas hundreds of miles distant from the earthquake’s epicenter. Historic earthquakes have caused strong ground shaking and damage in the San Francisco Bay Area, the most recent being the Loma Prieta earthquake (moment magnitude 6.9) in October 1989. The epicenter was approximately 50 miles south of the project site, and the earthquake caused very strong ground shaking for about 20 seconds and resulted in varying degrees of structural damage as far as 50 miles away. This event produced a moderate (Modified Mercalli VI) shaking intensity in the project area (ABAG, 2009a). The 1906 San Francisco earthquake, with an estimated moment magnitude of 7.9, produced a strong (Modified Mercalli VII) shaking intensity in the project area (ABAG, 2009b).

The common way to describe ground motion during an earthquake is the duration of the shaking. However, a common measure of ground motion is also the peak ground acceleration (PGA). The PGA for a given component of motion is the largest value of horizontal acceleration obtained from a seismograph. PGA is expressed as the percentage of the equivalent acceleration of gravity (g), which is approximately 980 centimeters per second squared. (In terms of automobile acceleration, one “g” of acceleration is a rate of increase in speed equivalent to a car accelerating from a standstill to 60 mph in less than 3 seconds.) For comparison purposes, the maximum peak acceleration value recorded during the Loma Prieta earthquake was in the vicinity of the epicenter, near Santa Cruz, at 0.64 g. The lowest values recorded were 0.06 g in the bedrock on Yerba Buena Island.

An earthquake on the Hayward fault would likely produce more severe ground shaking than was observed during the Loma Prieta earthquake if the epicenter of the earthquake were closer in vicinity to the project site, and along the Hayward fault. Probabilistic seismic hazard maps indicate that peak ground acceleration in the project region could reach or exceed 0.65 g (CGS, 2003).

Surface Fault Rupture Seismically induced ground rupture is defined as the physical displacement of surface deposits in response to an earthquake’s seismic waves. The magnitude, sense, and nature of fault rupture can vary for different faults or even along different strands of the same fault. Ground rupture is considered more likely along active faults (see Table 4.8-2).

The project site is not within an Alquist-Priolo Fault Rupture Hazard Zone, as designated through the Alquist-Priolo Earthquake Fault Zoning Act, and no mapped active faults are known to pass

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Liquefaction Liquefaction is a transformation of soil from a solid to a liquefied state during which saturated soil temporarily loses strength resulting from the buildup of excess pore water pressure, especially during earthquake-induced cyclic loading. Soils susceptible to liquefaction include saturated loose to medium dense sands and gravels, low-plasticity silts, and some low-plasticity clay deposits. Liquefaction and associated failures could damage foundations, disrupt utility service, and can cause damage to roadways.

Hazard maps available through ABAG and produced by the USGS depict liquefaction and lateral spreading hazards for the entire Bay Area in the event of a significant seismic event (ABAG, 2009d).6 According to these maps, the project area has moderate liquefaction susceptibility. However, the geotechnical site investigation for the proposed new patient care pavilion hospital tower indicated that the soils are relatively dense and the groundwater level was recorded at approximately 47 below ground surface indicating a low probability for liquefaction (Geomatrix, 2008a). The geotechnical site investigation for the proposed new central parking structure concluded that the western half of the proposed site might be subject to liquefiable sandy layers observed at depths below approximately 32 feet (AMEC, 2009).

Landslides Slope failures, commonly referred to as landslides, include many phenomena that involve the downslope displacement and movement of material, either triggered by static (i.e., gravity) or dynamic (i.e., earthquake) forces. A slope failure is a mass of rock, soil, and debris displaced downslope by sliding, flowing, or falling. Exposed rock slopes undergo rockfalls, rockslides, or rock avalanches, while soil slopes experience shallow soil slides, rapid debris flows, and deep- seated rotational slides. Landslides may occur on slopes of 15 percent or less; however, the probability is greater on steeper slopes that exhibit old landslide features such as scarps, slanted vegetation, and transverse ridges. Landslide-susceptible areas are characterized by steep slopes and downslope creep of surface materials. Debris flows consist of a loose mass of rocks and other granular material that, if saturated and present on a steep slope, can move downslope. The rate of rock and soil movement can vary from a slow creep over many years to a sudden mass movement. Landslides occur throughout the state of California, but the density of incidents increases in zones of active faulting.

The project site is not located in an area where earthquake-induced landslides are likely to occur because of the relatively gentle slopes of the project area. Therefore, the risk of landslide at the site is low and is not discussed further in this analysis.

6 Lateral spreading is a ground failure associated with liquefaction and generally results from predominantly horizontal displacement of materials toward relatively unsupported free slope faces.

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Geologic Hazards Considering the geologic context of the project area and nature of the project, other typical geologic hazards could include soil erosion and expansive soil. These hazards are discussed briefly here.

Expansive Soils Expansive soils possess a “shrink-swell” behavior. Shrink-swell is the cyclic change in volume (expansion and contraction) that occurs in fine-grained clay sediments from the process of wetting and drying. Structural damage to buildings can occur over a long period of time, usually as a result of inadequate soil and foundation engineering or the placement of structures directly on expansive soils. Soils in the area have been characterized as having a medium to high expansion potential, or shrink-swell behavior. According to the initial geotechnical evaluation no expansive soils were identified at the project site (Geomatrix, 2008a). However, a supplemental investigation identified an area with near surface fill materials that were considered to be potential expansive (Geomatrix, 2008b). In addition, the geotechnical investigation for the proposed central parking structure found clayey soils in the western portion of the proposed garage site that are considered highly expansive (AMEC, 2009).

Soil Erosion Erosion is the wearing away of soil and rock by processes such as mechanical or chemical weathering, mass wasting, the action of waves, wind and underground water. Excessive soil erosion can eventually lead to damage of building foundations and roadways. The proposed project includes excavation for graded soils, use of fill material, and possibly additional imported soil material. However, as part of building design requirements, the project area will be sloped for rapid removal of surface water runoff from the foundation systems, which would reduce the risk of soil erosion that would lead to damage of building foundations and roadways.

4.8.2 Regulatory Setting

California Building Code The California Building Code (CBC) has been codified in the California Code of Regulations (CCR) as Title 24, Part 2. Title 24 is administered by the California Building Standards Commission, which by law is responsible for coordinating all building standards. Under state law, all building standards must be centralized in Title 24 or they are not enforceable. The purpose of the CBC is to establish minimum standards to safeguard the public health, safety and general welfare through structural strength, means of egress facilities, and general stability by regulating and controlling the design, construction, quality of materials, use and occupancy, location, and maintenance of all building and structures within its jurisdiction. The CBC is based on the International Building Code. The 2007 CBC is based on the 2006 International Building Code (IBC) published by the International Code Conference. In addition, the CBC contains necessary California amendments, which are based on the American Society of Civil Engineers (ASCE) Minimum Design Standards 7-05. ASCE 7-05 provides requirements for general structural design and includes means for determining earthquake loads as well as other loads (flood, snow, wind, etc.) for inclusion into building codes. The provisions

ABSMC Summit Campus Seismic Upgrade and 4.8-8 ESA / 207376 Master Plan Project Draft EIR December 2009 4. Environmental Setting, Impacts, Standard Conditions of Approval and Mitigation Measures 4.8 Geology, Soils, and Geohazards of the CBC apply to the construction, alteration, movement, replacement, and demolition of every building or structure or any appurtenances connected or attached to such buildings or structures throughout California.

The earthquake design requirements take into account the occupancy category of the structure, site class, soil classifications, and various seismic coefficients, which are used to determine a Seismic Design Category (SDC) for a project. The SDC is a classification system that combines the occupancy categories with the level of expected ground motions at the site and ranges from SDC A (very small seismic vulnerability) to SDC E/F (very high seismic vulnerability and near a major fault). Design specifications are then determined according to the SDC.

1983 Alfred E. Alquist Hospital Seismic Safety Act (Seismic Safety Act), Senate Bill 1953 (SB 1953) and the OSHPD All acute care medical center properties fall under the jurisdiction of the Alquist Act, as amended in 1994 by SB 1953. The Alquist Act requires medical facilities to comply with seismic safety building standards as defined by the Office of Statewide Health Planning and Development (OSHPD) within specific time frames.

OSHPD is a department of the California Health and Human Services Agency and is responsible for carrying out the provisions of the Alquist Act and serves as the building authority for acute care facilities in lieu of local jurisdictions. OSHPD’s primary goals include assessing California’s healthcare infrastructure, managing the healthcare workforce, providing healthcare outcomes information to the public, insuring healthcare facilities development loans, and running the Hospital Seismic Safety Program, which enforces building seismic safety. The Hospital Building Safety Board (HBSB) further advises the director of OSHPD on the administration of the Act and acts as a board of appeals for hospital seismic safety issues.

The Act was adopted in part so that after a major earthquake or disaster, hospital facilities can continue to provide care to their current occupants as well as any new patients that might arrive after the event. During and after the 1994 Northridge earthquake, hospitals that were compliant with the Act sustained minimal structural damage and continued to function. Hospitals that were not compliant sustained major damage and had to be abandoned (OSHPD, 2001).

Compliance with the Alquist Seismic Safety Act and SB 1953 (the Act) For a hospital building to remain classified as an acute care hospital facility, and thus be compliant with the Act, the owner of the building must do the following:

1. Complete seismic evaluations with procedures as defined by OSHPD to identify non- compliant buildings,

2. Prepare a comprehensive plan and schedule for how each building will become compliant with the Act, within 3 years of the evaluation, and

3. Submit the report and a compliance plan to OSHPD for review and approval (California State Senate, 1994).

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In the process of compliance, OSHPD and the hospital building owner evaluates both nonstructural (communications, medical gas, etc.) and structural (actual building structure) components of acute care hospital facilities that might sustain damage during a shaking event. Nonstructural components are put into a Nonstructural Performance Category (NPC), and structural components are put into a Structural Performance Category (SPC). Thus, each acute care facility is assigned an NPC rating and an SPC rating that is put into OSHPD’s database for review. OSHPD evaluates SPC and NPC ratings separately. As part of the ratings evaluation process, OSHPD and affiliated engineers examine structural drawings and submitted reports of upgrades, if any, that have occurred to each hospital building. These evaluations may include an onsite visit by the Area Compliance Officer (ACO) and/or the District Structural Engineer (DSE) of OSHPD. After the evaluation process, the rating is either confirmed or changed according to OSHPD’s review and determination, and OSHPD provides guidance to the hospital property owner regarding further required upgrades.

NPC and SPC Ratings Each possible NPC and SPC rating is described below. In general, low ratings (e.g., SPC-1) mean a hospital building systems are not prepared for a disaster, and high ratings (e.g., SPC-4) mean hospital building systems are prepared for a disaster. If the building is determined to not be in compliance with the Act based on the following NPC and SPC ratings, seismic retrofit regulations (Division III-R) shall be applied to guide the building’s retrofit, thus increasing the NPC and SPC rating of the building (OSHPD, 2001). New construction that is designed and constructed to current seismic and building code standards would be exempt from NPC and SPC ratings although in full compliance with the Act.

Nonstructural Ratings NPC-0: No rating was reported to OSHPD.

NPC-1: Basic systems used in life safety and care are not properly anchored, and will not survive an earthquake event. Communications, emergency power, medical gas, and fire alarm systems must be anchored by January 1, 2002.

NPC-2: Communications systems, emergency power supplies, bulk medical gas systems, fire alarm systems, and emergency lighting and exit signs are properly anchored.

NPC-3: Basic systems used in life safety and care are properly anchored in critical areas of the hospital. If there is not significant structural damage, basic emergency medical care should be able to continue.

NPC-4: All architectural, mechanical, electrical systems, components and equipment, and hospital equipment are properly anchored. If there is not significant structural damage and problems with water and sewer systems, basic emergency medical care should be able to continue.

NPC-5: All basic systems used in life safety and care are properly anchored. In addition, the building has water and wastewater holding tanks (integrated into the plumbing system) and an on-site fuel supply that will last through 72 hours of acute care operations.

Radiological service can also continue.

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Structural Ratings SPC-0: No rating was reported to OSHPD.

SPC-1: These buildings have a high risk of collapse in an earthquake, and are a significant safety hazard to the public. These buildings must be retrofitted, replaced, or removed from acute care classification by January 1, 2008.

SPC-2: These buildings are in compliance with pre-1973 California Building Code, but are not in compliance with the Alquist Hospital Facilities Seismic Safety Act. These buildings do not pose a significant safety hazard, but might not be functional after a strong earthquake. These buildings must be compliant with the Alquist Hospital Facilities Seismic Safety Act by January 1, 2030 or removed from acute care classification.

SPC-3: These buildings are compliant with the Alquist Hospital Facilities Seismic Safety Act. These buildings might sustain structural damage and might not be able to provide care after an event, but they have been constructed or reconstructed under OSHPD building permits. They can be used to January 1, 2030 and beyond.

SPC-4: These buildings are compliant with the Alquist Hospital Facilities Seismic Safety Act. These buildings may sustain structural damage and might not be able to provide care after an event, but they have been constructed or reconstructed under OSHPD building permits. They can be used to January 1, 2030 and beyond.

SPC-5: These buildings are compliant with the Alquist Hospital Facilities Seismic Safety Act. These buildings are reasonably capable of providing care after an event, and they have been constructed or reconstructed under OSHPD building permits. They can be used to January 1, 2030 and beyond.

For purposes of assessing the NPC and SPC ratings of the Merritt Pavilion (the component of the proposed project that ABSMC is undertaking specifically to comply with the operational and legal mandates of SB 1953), the Merritt Pavilion, which is the main hospital building that houses the patient care and emergency services facilities, is made of up 17 individual structures. Each structure has its own NPC and SPC rating. All 17 structures have an NPC-1 rating. Of the 17 structures, 10 structures that are the oldest (built prior to 1964) and that generally make up the northern half of the pavilion, have an SPC-1 or SPC-2 rating. The remaining 7 structures are newer (built after 1974) and have SPC ratings ranging from SPC-3 to SPC-5 (Degenkolb, 2004).

City of Oakland Regulations

Ordinances and Oakland Municipal Code The City of Oakland implements the following regulations and ordinances aimed at reducing soil erosion and protecting water quality and water resources:

The City’s Grading Ordinance (Ordinance No. 10312 is intended to reduce erosion during grading and construction activities. Pursuant to this ordinance, Chapter 13.16 of the Oakland Municipal Code requires that a project applicant obtain grading permits for earth moving activities under specified conditions of 1) volume of earth to be moved, 2) slope characteristics, 3) areas where "land disturbance" or 4) stability problems have been reported. To obtain a grading permit, the

ABSMC Summit Campus Seismic Upgrade and 4.8-11 ESA / 207376 Master Plan Project Draft EIR December 2009 4. Environmental Setting, Impacts, Standard Conditions of Approval and Mitigation Measures 4.8 Geology, Soils, and Geohazards project applicant must prepare and submit to the Public Works Agency a soils report, a grading plan, and an erosion and sedimentation control plan for approval (Oakland Municipal Code, 2008).

The City also implements the Sedimentation and Erosion Control Ordinance (Ordinance No. 10446) also aimed at reducing erosion during construction and operations. As a condition of development or redevelopment, the Chief of Building Services or his or her designee may require implementation of continuous or post construction best management practices such as good housekeeping practices or storm water treatment systems (Oakland Municipal Code, 2008).

Building Services Division In addition to compliance with building standards set forth by the 2006 IBC and 2007 CBC, the project applicant will be required to submit to the Oakland Building Services Division an engineering analysis accompanied by detailed engineering drawings for review and approval prior to excavation, grading, or construction activities on the project site. Specifically, an engineering analysis report and drawings of relevant grading or construction activities on a project site would be required to address constraints and incorporate recommendations identified in geotechnical investigations. These required submittals and City reviews ensure that the buildings are designed and constructed in conformance with the seismic and other requirements of all applicable building code regulations, pursuant to standard City of Oakland procedures.

City of Oakland Standard Conditions of Approval and Uniformly Applied Development Standards Imposed as Standard Conditions of Approval The City’s Standard Conditions of Approval relevant to geology and soils are listed below for reference. If the proposed project is approved by the City, then all applicable Standard Conditions of Approval would be adopted as conditions of approval and required of the project to help ensure less-than-significant impacts to geology and soils. The Standard Conditions of Approval are incorporated and required as part of the project, so they are not listed as mitigation measures. Standard Conditions of Approval applicable to potential geologic impacts due to the project include:

GEO-1: Erosion and Sedimentation Control Plan Prior to any grading activities. a) The project applicant shall obtain a grading permit if required by the Oakland Grading Regulations pursuant to Section 15.04.780 of the Oakland Municipal Code. The grading permit application shall include an erosion and sedimentation control plan for review and approval by the Building Services Division. The erosion and sedimentation control plan shall include all necessary measures to be taken to prevent excessive stormwater runoff or carrying by stormwater runoff of solid materials on to lands of adjacent property owners, public streets, or to creeks as a result of conditions created by grading operations. The plan shall include, but not be limited to, such measures as short-term erosion control planting, waterproof slope covering, check dams, interceptor ditches, benches, storm drains, dissipation structures, diversion dikes, retarding berms and barriers, devices to trap, store and filter out sediment, and stormwater retention basins. Off-site work by the project applicant may be necessary.

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The project applicant shall obtain permission or easements necessary for off-site work. There shall be a clear notation that the plan is subject to changes as changing conditions occur. Calculations of anticipated stormwater runoff and sediment volumes shall be included, if required by the Director of Development or designee. The plan shall specify that, after construction is complete, the project applicant shall ensure that the storm drain system shall be inspected and that the project applicant shall clear the system of any debris or sediment.

Ongoing throughout grading and construction activities. b) The project applicant shall implement the approved erosion and sedimentation plan. No grading shall occur during the wet weather season (October 15 through April 15) unless specifically authorized in writing by the Building Services Division.

GEO-2: Vibrations Adjacent Historic Structures Prior to issuance of a demolition, grading or building permit. The project applicant shall retain a structural engineer or other appropriate professional to determine threshold levels of vibration and cracking that could damage the adjacent historic structure and design means and methods of construction that shall be utilized to not exceed the thresholds.

GEO-3: Soils Report Required as part of the submittal of a Tentative Tract or Tentative Parcel Map. A preliminary soils report for each construction site within the project area shall be required as part if this project and submitted for review and approval by the Building Services Division. The soils reports shall be based, at least in part, on information obtained from on-site testing. Specifically the minimum contents of the report should include:

A. Logs of borings and/or profiles of test pits and trenches: a) The minimum number of borings acceptable, when not used in combination with test pits or trenches, shall be two (2), when in the opinion of the Soils Engineer such borings shall be sufficient to establish a soils profile suitable for the design of all the footings, foundations, and retaining structures. b) The depth of each boring shall be sufficient to provide adequate design criteria for all proposed structures. c) All boring logs shall be included in the soils report.

B. Test pits and trenches a) Test pits and trenches shall be of sufficient length and depth to establish a suitable soils profile for the design of all proposed structures. b) Soils profiles of all test pits and trenches shall be included in the soils report.

C. A plat shall be included which shows the relationship of all the borings, test pits, and trenches to the exterior boundary of the site. The plat shall also show the location of all proposed site improvements. All proposed improvements shall be labeled.

D. Copies of all data generated by the field and/or laboratory testing to determine allowable soil bearing pressures, sheer strength, active and passive pressures, maximum allowable slopes where applicable and any other information which may

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be required for the proper design of foundations, retaining walls, and other structures to be erected subsequent to or concurrent with work done under the grading permit.

E. Soils Report. A written report shall be submitted which shall include, but is not limited to, the following: a) Site description; b) Local and site geology; c) Review of previous field and laboratory investigations for the site; d) Review of information on or in the vicinity of the site on file at the Information Counter, City of Oakland, Office of Planning and Building; e) Site stability shall be addressed with particular attention to existing conditions and proposed corrective attention to existing conditions and proposed corrective actions at locations where land stability problems exist; f) Conclusions and recommendations for foundations and retaining structures, resistance to lateral loading, slopes, and specifications, for fills, and pavement design as required; g) Conclusions and recommendations for temporary and permanent erosion control and drainage. If not provided in a separate report they shall be appended to the required soils report; h) All other items which a Soils Engineer deems necessary; i) The signature and registration number of the Civil Engineer preparing the report.

F. The Director of Planning and Building may reject a report that she/he believes is not sufficient. The Director of Planning and Building may refuse to accept a soils report if the certification date of the responsible soils engineer on said document is more than three years old. In this instance, the Director may be require that the old soils report be recertified, that an addendum to the soils report be submitted, or that a new soils report be provided.

GEO-4: Geotechnical Report Required as part of the submittal of a tentative Tract Map or tentative Parcel Map. a) A site-specific, design level, Fault Zone geotechnical investigation for each construction site within the project area shall be required as part if this project and submitted for review and approval to the Building Services Division. Specifically: i. Each investigation shall include an analysis of expected ground motions at the site from identified faults. The analyses shall be accordance with applicable City ordinances and polices, and consistent with the most recent version of the California Building Code, which requires structural design that can accommodate ground accelerations expected from identified faults. ii. The investigations shall determine final design parameters for the walls, foundations, foundation slabs, surrounding related improvements, and infrastructure (utilities, roadways, parking lots, and sidewalks). iii. The investigations shall be reviewed and approved by a registered geotechnical engineer. All recommendations by the project engineer, geotechnical engineer, shall be included in the final design, as approved by the City of Oakland.

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iv. The geotechnical report shall include a map prepared by a land surveyor or civil engineer that shows all field work and location of the “No Build” zone. The map shall include a statement that the locations and limitations of the geologic features are accurate representations of said features as they exist on the ground, were placed on this map by the surveyor, the civil engineer or under their supervision, and are accurate to the best of their knowledge. v. Recommendations that are applicable to foundation design, earthwork, and site preparation that were prepared prior to or during the projects design phase, shall be incorporated in the project. vi. Final seismic considerations for the site shall be submitted to and approved by the City of Oakland Building Services Division prior to commencement of the project. vii. A peer review is required for the Geotechnical Report. Personnel reviewing the geologic report shall approve the report, reject it, or withhold approval pending the submission by the applicant or subdivider of further geologic and engineering studies to more adequately define active fault traces.

b) Tentative Tract or Parcel Map approvals shall require, but not be limited to, approval of the Geotechnical Report.

4.8.3 Impacts and Mitigation Measures

Significance Criteria The project would have a significant impact on the environment if it would:

Specifically,

1. Expose people or structures to substantial risk of loss, injury, or death involving:

• Rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map or Seismic Hazards 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 Publications 42 and 117 and PRC §2690 et. seq.); • Strong seismic ground shaking; • Seismic-related ground failure, including liquefaction, lateral spreading, subsidence, collapse; or • Landslides;

2. Result in substantial soil erosion or the loss of topsoil, creating substantial risks to life, property, or creeks/waterways;

3. Be located on expansive soils, as defined in Table 18-1-B of the Uniform Building Code (1994, as it may be revised), creating substantial risks to life or property;

4. Be located above a well, pit, swamp, mound, tank vault, or unmarked sewer line, creating substantial risks to life or property;

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5. Be located above landfills for which there is no approved closure and post-closure plan, or unknown fill soils, creating substantial risks to life or property; or

6. Have soils incapable of adequately supporting the use of septic tanks or alternative wastewater disposal systems where sewers are not available for the disposal of wastewater.

Approach to Analysis Based on the proposed project plan and its geographical location, the proposed project would not result in impacts related to the following criteria. No impact discussion is provided for these topics for the following reasons:

• Fault Rupture. The faults most susceptible to earthquake rupture are active faults, which are faults that have experienced surface displacement within the last 11,000 years. There are no active faults that cross the project area, and the nearest project facility to an active fault is more than 2 miles away. Therefore, the potential for fault rupture to affect the proposed project elements is very low.

• Landslides. The Plan area does not contain slopes that are susceptible to landslides or slope failure. The gentle sloping topography of the area puts the potential for landslides or slope failure to affect any of the proposed development or redevelopment in the Plan area at very low and is therefore not discussed further.

• Wastewater Disposal. The Project area is located within an urban area where all development will be able to tie into existing wastewater infrastructure. Therefore, none of the development or redevelopment will require the use of septic or other alternative disposal wastewater systems, and therefore no impact associated with this hazard.

Compliance with Seismic Safety Act A primary objective of the proposed project is redevelopment of the acute care facilities to comply with the Alquist Seismic Safety Act (SB 1953) by the deadline of January 1, 2013. The proposed project will assure that medical services will continue to be provided by a licensed acute care facility on the existing site during construction and thereafter without disruption. The principal objectives also include construction of new medical office buildings, classrooms and other structures which are not considered an essential structure and do not fall under the guidelines presented in California Geological Survey – Note 48, Checklist for the Review of Engineering Geology and Seismology Reports for California Public Schools, Hospitals, and Essential Services Buildings (Note 48). The main purpose of the proposed project is to meet the provisions of SB 1953 by 2013. Construction of new acute care facility buildings according to the 2007 California Building Code, would meet the requirements of the Act.

Operational Impacts

Impact GEO-1: Redevelopment in the project area could expose people or structures to seismic hazards such as groundshaking or liquefaction. (Less than Significant)

The proposed project is located in the San Francisco Bay Area, a region of intense seismic activity. Recent studies by the USGS indicate there is a 62 percent likelihood of a Richter magnitude 6.7

ABSMC Summit Campus Seismic Upgrade and 4.8-16 ESA / 207376 Master Plan Project Draft EIR December 2009 4. Environmental Setting, Impacts, Standard Conditions of Approval and Mitigation Measures 4.8 Geology, Soils, and Geohazards or higher earthquake occurring in the Bay Area before 2032. The Hayward Fault Zone, the active fault nearest the project site, is the most likely of the active Bay Area faults to experience a major earthquake. A seismic event in the Bay Area could produce ground shaking at the proposed project area that is very strong (MM-VIII) (ABAG, 2009c). Seismic shaking can also trigger ground-failures caused by liquefaction.7 The project site is not located in a Seismic Hazard Zone for liquefaction, as designated by the CGS (CGS, 2009). In addition, the geotechnical investigation prepared for the proposed new patient care pavilion hospital tower indicated that based on observed subsurface materials taken during field exploration and an observed depth to groundwater of approximately 47 feet below grade, the potential for liquefaction was very low (Geomatrix, 2008a). However, the geotechnical investigation prepared for the proposed central parking structure found that the western portion of the garage site had saturated sand layers that have a moderate to high potential for liquefaction (AMEC, 2009). The report also concluded that deep foundation systems such as drilled piers could effectively mitigate the potential for liquefaction for the proposed structure.

Based on the MMI scale, an earthquake of this intensity on the Hayward fault would cause considerable structural damage, even in well-designed structures. Ground shaking of this intensity could lead to structural building damage, movement or damage of internal building components, or power failure. Substantial cracks could appear in the ground, and the shaking could cause other secondary damaging effects such as the failure of underground pipes. As a comparison, the great 1906 San Francisco earthquake, with an M 7.9, produced strong (MM-VII) shaking intensities in the project area (ABAG, 2008a). A characteristic earthquake on the Calaveras, San Andreas, or Concord-Green Valley (listed in Table 4.8-2) could produce moderate (MM-VI) to strong (MM-V) ground shaking intensities (ABAG, 2008a). Earthquakes of this intensity may move heavy furniture and cause slight damage.

In accordance with the State Health and Safety Code, the OSHPD is required to review the structural systems and related details of the construction or renovation of medical buildings with acute care facilities, as well as the recommendations of any site-specific geotechnical investigations prepared for those buildings, to ensure compliance with the Seismic Safety Act and the CBC. OSHPD’s comments and the recommendations from the geotechnical investigation would be submitted to the City of Oakland Building Services Division. However, local jurisdictions are preempted from the enforcement of all building standards published in the California Building Standards Code relating to the regulation of hospital buildings and the enforcement of other regulations adopted pursuant to the State Health and Safety Code and all other applicable state laws. In addition to reviewing the proposed structural plans, OSHPD is responsible for overseeing construction of the proposed hospital building to ensure that construction complies with the approved plans. For all proposed non-acute care facilities such as parking structures, the Project Sponsor would be required to adhere to the California Building Code and City of Oakland Building Services Division requirements.

7 Liquefaction is the process by which saturated, loose, fine-grained, granular, soil, like sand, behaves like a dense fluid when subjected to prolonged shaking during an earthquake.

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In accordance with City of Oakland requirements, the Project Sponsor would be required to prepare a geotechnical report for the project that includes generally accepted and appropriate engineering techniques for determining the susceptibility of the project site to various geologic and seismic hazards. The geotechnical report would include an analysis of ground shaking effects, liquefaction potential, and provide recommendations to reduce these hazards. Because the project site is within a Seismic Hazard Zone for liquefaction, recommendations for the mitigation and reduction of liquefaction would be prepared in accordance with CGS Guidelines for Evaluating and Mitigating Seismic Hazards (California Division of Mines and Geology Special Publication 117, 1997). Geotechnical and seismic design criteria would conform to engineering recommendations consistent with the seismic requirements set forth in the California Code of Regulations, Title 24, California Building Standards Code in effect at the time of permit application.

In addition to compliance with building standards set forth in the California Code of Regulations, Title 24, California Building Standards Code, the project sponsor would be required to submit an engineering analysis accompanied by detailed engineering drawings to the City of Oakland Building Services Division prior to excavation, grading, or construction activities on the project site. This is consistent with standard City of Oakland practices to ensure that all buildings are designed and built in conformance with the seismic requirements of the City of Oakland Building Code. An engineering analysis report and drawings and relevant grading or construction activities on a project site would be required to address constraints and incorporate recommendations identified in geotechnical investigations. These required submittals ensure that the buildings are designed and constructed in conformance with the requirements of all applicable building code regulations, pursuant to standard City procedures. Standard Condition GEO-4, Geotechnical Report, in addition to the OSHPD requirements would ensure that the project conforms to all applicable building code regulations. Construction according to these requirements would ensure that potential impacts from seismic groundshaking or liquefaction would be reduced to less than significant levels.

Mitigation: None required.

Impact GEO-2: Redevelopment in the project area could be subjected to geologic hazards, including expansive soils, subsidence, seismically induced settlement and differential settlement. (Less than Significant)

Soils containing a high percentage of clays are generally most susceptible to expansion. Expansive soils can damage foundations of above-ground structures, paved roads and streets, and concrete slabs. As previously discussed, the geotechnical evaluation originally reported that expansive soils were not known to be present on the project site for the proposed new patient care pavilion but were observed at the proposed central parking structure (Geomatrix, 2008a and AMEC, 2009). Also, in the supplemental geotechnical report, further investigation revealed that some near surface site soils were considered potentially expansive. In addition, the findings of the geotechnical evaluation concluded that due to the relatively dense and stiff alluvial materials that subsidence and seismically induced settlement (including differential settlement)

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The geotechnical evaluation identified various construction methods and building designs for all proposed structures under the project that would serve to overcome the potential for these geologic hazards at the site. Specifically, these methods include the use of drilled piers or similar deep foundation systems, shallow mat foundations with soil anchors, and industry standard site preparation measures such as placement of engineered fill under appropriate compaction specifications in compliance with building code specifications (Geomatrix, 2008a and AMEC, 2009).

The City of Oakland requires preparation of a geotechnical report, as well as compliance with and implementation of the geotechnical report recommendations. Compliance with the geotechnical report recommendations, required as part of Standard Condition GEO-4, Geotechnical Report, would reduce the potential for the project to result in geological hazards such as soil expansion and differential settlement.

Mitigation: None required.

Cumulative Geology, Soils, and Seismicity Impacts

Cumulative Context As discussed above, the project would not result in potentially significant project-level impacts related to hazardous geologic and seismic conditions. Although the entire Bay Area is situated within a seismically active region with a wide range of geologic and soil conditions, these conditions can vary widely within a short distance, making the cumulative context for potential impacts resulting from exposing people and structures to related risks one that is more localized or even site-specific. The project site is located near other development and has the opportunity to combine with structural damage from other past, present, and reasonably foreseeable future projects. These include projects within this area, and on the City of Oakland’s Active Major Development Projects list provided on page 4.1-5, under “Planned Projects within the Project Site Vicinity.”

Impact GEO-3: The development proposed as part of the project, when combined with past, present, existing, approved, pending, and reasonably foreseeable future development in the vicinity, would not result in significant cumulative impacts with respect to geology, soils or seismicity. (Less than Significant)

Development of the project, with implementation of the Standard Conditions of Approval discussed above, would have less than significant impacts related to exposing persons or structures to geologic, soils, or seismic hazards. The project, combined with other past, present, existing, approved, pending and reasonably foreseeable future development in the area, could result in increased population and development in an area subjected to seismic risks and hazards. While the number of people visiting, living and working in the area will increase incrementally,

ABSMC Summit Campus Seismic Upgrade and 4.8-19 ESA / 207376 Master Plan Project Draft EIR December 2009 4. Environmental Setting, Impacts, Standard Conditions of Approval and Mitigation Measures 4.8 Geology, Soils, and Geohazards exposing additional people to seismic and geological hazards over time, the risk to people and property would be reduced through the upgrading or demolishing of older buildings that are seismically unsafe. Older buildings would be seismically retrofitted and newer buildings would be constructed to stricter building codes. Thus, implementation of the proposed project and other foreseeable projects in the area would be required to implement applicable Standard Conditions of Approval related to geology, soils, and seismicity (Standard Conditions GEO-1, Erosion and Sedimentation Control Plan, GEO-2, Vibrations Adjacent to Historic Structures, GEO-3, Soils Report, and GEO-4, Geotechnical Report), and would be required to adhere to all federal, state, and local programs, requirements and policies pertaining to building safety and construction permitting. All projects would be required to adhere to the City’s Building Code and grading ordinance. Therefore, the project, combined with other foreseeable development in the area, would not result in a cumulatively significant impact by exposing people or structures to risk related to geologic hazards, soils, and/or seismic conditions.

Mitigation: None required.

______

References – Geology, Soils, and Geohazards

AMEC-Geomatrix (AMEC), Engineering Geologic and Geotechnical Evaluation, New Central Parking Structure, Oakland CA, March 2009.

Association of Bay Area Governments (ABAG), ABAG Shaking Intensity Maps and Information, 1989 Loma Prieta Earthquake Modeled shaking for Oakland – North, http://gis.abag.ca.gov/website/Shaking-Maps/viewer.htm, accessed March 2009 (2009a).

Association of Bay Area Governments (ABAG), ABAG Shaking Intensity Maps and Information, 1906 San Andreas Earthquake Modeled shaking for Oakland – North http://gis.abag.ca.gov/website/Shaking-Maps/viewer.htm, accessed March 2009 (2009b).

Association of Bay Area Governments (ABAG), ABAG Shaking Intensity Maps and Information, Future Shaking Modeled Shaking Scenario Oakland-North, http://gis.abag.ca.gov/website/Shaking-Maps/viewer.htm, accessed March 2009 (2009c).

Association of Bay Area Governments (ABAG), ABAG Liquefaction Maps and Information, http://www.abag.ca.gov/bayarea/eqmaps/liquefac/liquefac.html, accessed March 2009 (2009d).

Association of Bay Area Governments (ABAG), 2008. On Shaky Ground; Modified Mercalli Intensity Scale., available online at www.abag.ca.gov/bayarea/eqmaps/doc/mmi.html, 2003.

California Geological Survey (CGS), 2002. How Earthquakes Are Measured, CGS Note 32.

California Geological Survey (CGS), Seismic Shaking Hazards in California, Based on the USGS/CGS Probabilistic Seismic Hazards Assessment (PSHA) Model, 2003 (revised April

ABSMC Summit Campus Seismic Upgrade and 4.8-20 ESA / 207376 Master Plan Project Draft EIR December 2009 4. Environmental Setting, Impacts, Standard Conditions of Approval and Mitigation Measures 4.8 Geology, Soils, and Geohazards

2003), http://redirect.conservation.ca.gov/cgs/rghm/pshamap/pshamain.html, accessed November 2008, published 2003.

City of Oakland Municipal Code, http://bpc.iserver.net/codes/oakland/, accessed November 2008.

Degenkolb Engineers, Summit Medical Center – Merritt Pavilion Revised Report, Appendix A: Site Plan (SB 1953 1.3.1.5), April 2004.

Geomatrix, Engineering Geologic and Geotechnical Evaluation, New Merritt Tower, Oakland CA, May 2008 (2008a).

AMEC-Geomatrix (Geomatrix), Supplemental Engineering Geologic and Geotechnical Evaluation, New Merritt Tower, Oakland CA, May 2008 (2008b).

Hart, E. W., Fault-Rupture Hazard Zones in California: Alquist-Priolo Special Studies Zones Act of 1972 with Index to Special Studies Zones Maps, California Division of Mines and Geology, Special Publication 42, 1990, revised and updated 1997.

Jennings, C. W., Fault Activity Map of California and Adjacent Areas, California Division of Mines and Geology Data Map No. 6, 1:750,000, 1994.

Peterson, M.D., Bryant, W.A., Cramer, C.H., Probabilistic Seismic Hazard Assessment for the State of California, California Division of Mines and Geology Open-File Report issued jointly with U.S. Geological Survey, CDMG 96-08 and USGS 96-706, 1996.

United States Geological Survey (USGS) Working Group on California Earthquake Probabilities (WG02), Open File Report 03-214, Earthquake Probabilities in the San Francisco Bay Region: 2002-2031, available online at http://pubs.usgs.gov/of/2003/of03-214/, 2003.

United States Geological Survey (USGS) The Uniform California Earthquake Rupture Forecast, Version 2 (UCERF 2), Open File Report 2007-1437, Earthquake Probabilities, available online at http://pubs.usgs.gov/of/2007/1437/, 2008.

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