South San Francisco City Council
December 13, 2023

Appendix E
Preliminary Geotechnical Site Assessment, Gallo Site,
Langan Engineering and Environmental Services Inc., October 27, 2020

27 October 2020
Ms. Tara Korlipara
Project Management Advisors
1 Tower Place, Suite 200
South San Francisco, California 94080
SUBJECT: Preliminary Geotechnical Site Assessment
Gallo Site
South San Francisco, California
Langan Project No.: 770675101
Dear Ms. Korlipara:

This letter presents our preliminary geotechnical site assessment for the Gallo site in South San Francisco, California. The site is southeast of the intersection of Forbes Boulevard and Eccles Avenue as shown on Figure 1. We understand you are performing a due diligence of the property.

The purpose of our study is to assist you with your due diligence and develop preliminary conclusions and recommendations regarding geotechnical aspects of the site. Our scope of services was performed in accordance with our proposal dated 12 October 2020.

1.0 SITE CONDITIONS AND PROPOSED DEVELOPMENT
The site is between Forbes Boulevard to the north, an open lot to the east, and commercial buildings and a trail corridor to the west and south as shown on Figure 2. The site is approximately

11.5 acres and is made up of five assessor parcels (APN 015-050-230, 015-050-590, 015-050- 710, 015-050-720, 015-050-730). The majority of the site is covered by two buildings, several small structures and parking lots.

Plans for the development are preliminary. We understand any proposed development would include demolition of the existing structures and construction of several new structures that could be at-grade or may have one to two levels of basements.

2.0 FIELD EXPLORATION AND LABORATORY TESTING
We reviewed previous geotechnical investigations performed in the vicinity of the site and available geologic maps. To further investigate subsurface conditions at the site, we drilled three test borings.

Prior to performing the field exploration, we:
 obtained soil boring/monitoring well permit from the San Mateo County Environmental Health Services Division (SMCEHSD)
 notified Underground Service Alert
 checked the boring locations for underground utilities using a private utility locator.

Preliminary Geotechnical Site Assessment
Gallo Site
South San Francisco, California
Langan Project No.: 770675101
27 October 2020

The approximate locations of the borings drilled at the site are shown on Figure 2. The borings were drilled on 19 October by Gregg Drilling, using a truck mounted hollow stem auger rig.

Three borings, designated as B-1 through B-3, were drilled to a depth of approximately 26.5 to

31.5 feet below ground surface (bgs). During drilling, our field engineer logged the borings and obtained representative samples of soil encountered for visual classification and laboratory testing.

Logs of test borings are presented in Appendix A on Figures A-1 through A-3. The soil and rock encountered in the borings was classified in accordance with the classification charts, presented on Figures A-4 and A-5.

Samples were obtained using the following split-barrel sampler types:
 Standard Penetration (SPT) sampler with a 2.0-inch-outside diameter and a 1.5-inch-inside diameter, without liners; and
 Sprague and Henwood (S&H) sampler with a 3.0-inch-outside diameter, 2.5-inch-inside diameter, lined with 2.43-inch-inside diameter, stainless-steel tubes.

The sampler types were chosen on the basis of soil type and desired sample quality for laboratory testing. In general, the S&H sampler was used to obtain samples in medium stiff to very stiff cohesive soils. The SPT sampler was used to evaluate the relative density of granular soils.

The SPT and S&H samplers were driven with a 140-pound, automatic, safety hammer falling 30 inches. The SPT and S&H samplers were driven up to 18 inches and the hammer blows required to drive the samplers every six inches of penetration were recorded and are presented on the boring logs. A “blow count” is defined as the number of hammer blows per six inches of penetration or less if the blow count approached 50 blows. The blow counts required to drive the S&H and SPT samples were converted to approximate SPT N-values using factors of 0.7 and 1.2, respectively, to account for sampler type and hammer energy and are shown on the boring logs.

The driving of a sampler was discontinued if the observed (recorded) blow count was 50 for six inches or less of penetration.

The blow counts used for this conversion were: 1) the last two blow counts if the sampler was driven more than 12 inches, 2) the last one blow count if the sampler was driven more than six inches but less than 12 inches, and 3) the only blow count if the sampler was driven six inches or less.

All borings were backfilled with cement grout at the completion of drilling in accordance with the requirements of SMCEHSD. The soil cuttings were placed in 55-gallon drums stored temporarily at the site.

The samples recovered from the field investigation were examined to verify their soil classification, and representative samples were selected for laboratory testing. Select samples Preliminary Geotechnical Site Assessment
Gallo Site
South San Francisco, California
Langan Project No.: 770675101
27 October 2020

of rock were analyzed for asbestos content to evaluate excavation considerations during construction. Results of the laboratory tests are included in Appendix B.

3.0 REGIONAL GEOLOGY
The site is on the east side of U.S. Highway 101, south of the eastern edge of San Bruno Mountain and west of San Bruno Point. Published geology maps indicate the site is underlain by Franciscan Complex bedrock, slope debris deposits and Colma Formation as shown on Figure 3.

Based on a review of the Preliminary Geologic Map of the San Francisco South 7.5’ Quadrangle, prepared by M.G. Bonilla, the western portion of site is underlain by Jurassic-aged sheared rocks (KJu) which includes small to large fragments of hard rock in a matrix of sheared rock derived mostly from shale, sandstone, and serpentinite of the Franciscan Complex. The remaining portion of the site is mapped as Qsr and Qc, which includes silty to clayey sand or gravel, sandy silt, clay and sandy clay.

The Hillside Fault is mapped at the northeast corner of the site and is further discussed in Section

6.1.2. 4.0 SUBSURFACE CONDITIONS
The site is generally underlain by several feet of sandy and gravely fill over medium dense to very dense sand and clayey sand over bedrock.

Bedrock, consisting of shale and serpentinite, which sometimes contains naturally occurring asbestos (NOA), of the Francisco Complex, was encountered approximately 3 and 2.5 feet below the ground surface (bgs) at B-1 and B-2, respectively. The results of asbestos testing indicated concentrations of asbestos ranging from zero to three percent. The rock is intensely fractured to crushed, plastic to friable, deeply weathered, and has soft to moderately hard hardness. Bedrock generally becomes deeper to the east and was not encountered in B-3.

B-3 consisted of about the three feet of sandy fill over medium dense to very dense sand of the Colma Formation with varying amounts of silt and clay and clayey sand down to the maximum depth explored of 31.5 feet.

Groundwater was encountered during our field investigation at B-3 at a depth of approximately 22 feet bgs during drilling. Groundwater was not in B-1 or B-2, but has been observed at the top of bedrock in the vicinity of the site. The observed groundwater level may not represent stabilized level, and may also fluctuate due to seasonal rainfall.

5.0 REGIONAL SEISMICITY
The major active faults in the area are the San Andreas, San Gregorio, and Hayward Faults. These and other faults of the region are shown on Figure 4. For each of the active faults within about 60 kilometers of the site, the distance from the site and estimated mean characteristic Moment Preliminary Geotechnical Site Assessment
Gallo Site
South San Francisco, California
Langan Project No.: 770675101
27 October 2020

magnitude1[2007 Working Group on California Earthquake Probabilities (WGCEP) (2008) and Cao et al. (2003)] are summarized in Table 1.

TABLE 1
Regional Faults and Seismicity
Fault Segment
Approx.

Distance from
fault (km)
Direction
from Site
Mean
Characteristic
Moment
Magnitude
N. San Andreas – Peninsula 5 West 7.23
N. San Andreas (1906 event) 5 West 8.05
San Gregorio Connected 14 West 7.50
N. San Andreas – North Coast 21 Northwest 7.51
Total Hayward 24 Northeast 7.00
Total Hayward-Rodgers Creek 24 Northeast 7.33
Monte Vista-Shannon 27 Southeast 6.50
Total Calaveras 38 East 7.03
Mount Diablo Thrust 40 Northeast 6.70
Green Valley Connected 45 Northeast 6.80
Rodgers Creek 48 North 7.07
Point Reyes 50 Northwest 6.90
Greenville Connected 55 East 7.00
West Napa 58 North 6.70
Figure 4 also shows the earthquake epicenters for events with magnitude greater than 5.0 from January 1800 through December 2014. Since 1800, four major earthquakes have been recorded on the San Andreas Fault. In 1836 an earthquake with an estimated maximum intensity of VII on the Modified Mercalli (MM) scale (Figure 5) occurred east of Monterey Bay on the San Andreas Fault (Toppozada and Borchardt 1998). The estimated Moment magnitude, Mw, for this earthquake is about 6.25. In 1838, an earthquake occurred with an estimated intensity of about VIII-IX (MM), corresponding to a Mw of about 7.5. The San Francisco Earthquake of 1906 caused the most significant damage in the history of the Bay Area in terms of loss of lives and property damage. This earthquake created a surface rupture along the San Andreas Fault from Shelter Cove to San Juan Bautista approximately 470 kilometers in length. It had a maximum intensity of XI (MM), a Mw of about 7.9, and was felt 560 kilometers away in Oregon, Nevada, and Los Angeles. The Loma Prieta Earthquake occurred on 17 October 1989, in the Santa Cruz Mountains with a Mw of 6.9, approximately 83 km from the site. The most recent earthquake to affect the Bay Area occurred on 24 August 2014 and was located on the West Napa fault, approximately 58 kilometers northeast of the site, with a Mw of 6.0.

1 Moment magnitude is an energy-based scale and provides a physically meaningful measure of the size of a faulting event. Moment magnitude is directly related to average slip and fault rupture area.

Preliminary Geotechnical Site Assessment
Gallo Site
South San Francisco, California
Langan Project No.: 770675101
27 October 2020

In 1868 an earthquake with an estimated maximum intensity of X on the MM scale occurred on the southern segment (between San Leandro and Fremont) of the Hayward Fault. The estimated Mw for the earthquake is 7.0. In 1861, an earthquake of unknown magnitude (probably a Mw of about 6.5) was reported on the Calaveras Fault. The most recent significant earthquake on this fault was the 1984 Morgan Hill earthquake (Mw = 6.2).

The 2014 Working Group for California Earthquake Probabilities (WGCEP) at the U.S. Geologic Survey (USGS) predicted a 72 percent chance of a magnitude 6.7 or greater earthquake occurring in the San Francisco Bay Area in 30 years (WGCEP 2015). More specific estimates of the probabilities for different faults in the Bay Area are presented in Table 2.

TABLE 2
WGCEP (2015) Estimates of 30-Year Probability (2014 to 2043) of a Magnitude 6.7 or Greater Earthquake
Fault
Probability
(percent)
Hayward-Rodgers Creek 32
N. San Andreas 33
Calaveras 25
Green Valley 7
San Gregorio 6
Greenville 6
Mount Diablo Trust 4

6.0 PRELIMINARY CONCLUSIONS AND RECOMMENDATIONS
On the basis of the available subsurface information we conclude that from a geotechnical standpoint, the site can be developed as planned. The primary geotechnical issues that should be addressed during design development are the presence of shallow bedrock containing asbestos, adequate foundation support, settlement behavior, and geologic hazards. Our discussions and preliminary recommendations regarding foundation alternatives and other geotechnical aspects of the project are presented in the remainder of this report.

6.1 Geologic Hazards
The site is in a seismically active area and will be subject to very strong shaking during a major earthquake. Strong ground shaking during an earthquake can result in ground failure such as that Preliminary Geotechnical Site Assessment
Gallo Site
South San Francisco, California
Langan Project No.: 770675101
27 October 2020

associated with soil liquefaction2, lateral spreading3, and cyclic densification4. Each of these conditions has been evaluated based on our literature review, field investigation and analyses, and is discussed in this section.

6.1.1 Liquefaction and Associated Hazards
Our review of the available nearby subsurface data indicates the sand below and above the groundwater level is typically sufficiently dense and/or has sufficient cohesion to resist liquefaction, lateral spreading, and seismic densification during a large earthquake on one of the nearby faults. Therefore, we conclude the potential for the onsite material to liquefy, laterally spread, and/or seismically densify is generally low. However, a low blow count in sand was encountered in Boring B-3 at a depths of 25 and 27.5 feet. This sample is part of the Colma Formation. Because hollow stem augers were used, the sample, which was below the groundwater table, may have been disturbed as water flowed into the augers and the blow count may not be representative; however, we have evaluated liquefaction potential using this data, which indicates liquefaction on the order of 1 inch could occur during a major earthquake. This is not typical of sand from the Colma Formation and should be further evaluated as part of design level investigation using either CPTs or a drill rig equipped with rotary wash equipment.

6.1.2 Fault Rupture
Historically, ground surface displacements closely follow the traces of geologically young faults.

The site is not within an Earthquake Fault Zone, as defined by the Alquist-Priolo Earthquake Fault Zoning Act.

The Hillside Fault is mapped at the northeast corner of the site as shown on Figure 3. It has been concluded that the Hillside Fault is an inactive fault, with the latest activity occurring at least

1.8 million years ago.

Based upon our review of published geologic maps, we found that no known active faults pass through the subject property. As a result, we conclude that the risk of fault offset through the site is negligible.

6.1.3 Tsunami
Recent published maps (California Emergency Agency, 2009) indicate the project site is not within the tsunami inundation zone; therefore, we conclude the potential risk by inundation from

2 Liquefaction is a transformation of soil from a solid to a liquefied state during which saturated soil temporally loses strength resulting from the buildup of excess pore water pressure, especially during earthquake-induced cyclic loading. Soil susceptible to liquefaction includes loose to medium dense sand and gravel, low-plasticity silt, and some low-plasticity clay deposits.
3 Lateral spreading is a phenomenon in which surficial soil displaces along a shear zone that has formed within an underlying liquefied layer. Upon reaching mobilization, the surficial blocks are transported downslope or in the direction of a free face by earthquake and gravitational forces. 4 Cyclic densification is a phenomenon in which non-saturated, cohesionless soil is compacted by earthquake vibrations, causing ground surface settlement.

Preliminary Geotechnical Site Assessment
Gallo Site
South San Francisco, California
Langan Project No.: 770675101
27 October 2020

tsunami to be low within the project site. However, the project civil engineer should evaluate the impact of sea level rise on the potential risk of inundation from a tsunami.

6.2 Excavation Considerations
It is anticipated that medium dense to very dense sand with varying amounts of silt and clay will be encountered in the excavations on the eastern two-thirds of the site, while Franciscan bedrock consisting of shale, sandstone, and serpentinite with varying degrees of weathering may be encountered in excavations in the western portion of the site. Although soil and weak bedrock may be excavated with conventional earth-moving equipment, such as loaders and backhoes, equipment capable of breaking the moderately hard bedrock, such as hoe-rams and large excavators may be required to remove some bedrock.

Serpentinite bedrock was encountered in the western portion of the site containing naturally occurring asbestos (NOA) in the form of green rock fragments exhibiting chrysotile fibers (based on visual observations). Chrysotile is a grey to green, soft, fibrous silicate mineral in the serpentine subgroup and is one of the most commonly encountered forms of NOA. The suspect asbestiform material was sampled and analyzed via the California Air Resource Board (CARB) 435 method for asbestos content. The results indicated concentrations of asbestos ranging from zero to three percent.

Due to the discovery of serpentinite bedrock containing NOA, the site will be subject to the CARB Asbestos Airborne Toxic Control Measure (ATCM) for construction, grading, quarrying, and surface mining operations dated July 2001 during redevelopment. The CARB’s Asbestos ATCM is enforced locally by the Bay Area Air Quality Management District (BAAQMD) and requires construction projects greater than one acre to prepare a site-specific ADMP for agency approval.

The ADMP specifies dust mitigation measures that must be initiated at the start and maintained throughout the duration of the excavation and grading activity per the ATCM. This generally includes the following:
 Construction vehicle speed at the work site must be limited to 15 miles per hour (mph) or less.
 Prior to any ground disturbance, sufficient water must be applied to the area to be disturbed to prevent visible dust emissions from crossing the property line.  Areas to be graded or excavated must be kept adequately wetted5to prevent visible dust emission from crossing the property line.
 Storage piles must be kept adequately wetted, treated with a chemical dust suppressant, or covered when material is not being added to or removed from the pile.  Equipment must be washed down before moving from the property onto a paved public road.

5 "Adequately Wetted" means sufficiently moistened with water to minimize the release of particulate matter into the ambient air as determined by the test method in ATCM subsection (h) (5).

Preliminary Geotechnical Site Assessment
Gallo Site
South San Francisco, California
Langan Project No.: 770675101
27 October 2020

 Visible track-out on the paved public road must be cleaned using a wet sweeping or a high-efficiency particulate air (HEPA) filter equipped vacuum device within 24 hours.

We anticipate that the project will be required to install a perimeter asbestos dust air monitoring network. This typically includes one upwind and two downwind asbestos dust monitors, the collection and analysis of daily samples (three per day at a minimum), and daily reporting of those results to BAAQMD throughout the duration of construction grading6. Once prepared, the ADMP will be enforceable at the site until post construction stabilization is complete, which generally includes one or all of the following:
 establishment of a vegetative cover;
 placement of at least three inches of non-asbestos-containing material; and/or  fully encapsulating the site in hardscape (i.e., asphalt, sidewalk, or building foundation).

Upon completion of construction grading and post-construction stabilization, a written closure request is submitted to BAAQMD and a final district approved site inspection is completed.

Based on the discovery of NOA, the subsurface lithology beneath the site, and proposed excavation activities, Langan recommends notifying BAAQMD on the discovery of NOA at the site and the preparation of an ADMP for BAAQMD review and approval for regulatory compliance prior to construction.

In addition, Langan recommends that the project team consult with a Certified Industrial Hygienist (CIH) to provide health and safety recommendations for potential worker exposure to NOA per California Occupational Safety and Health Administration (OSHA) requirements. Based on our experience on other NOA construction projects in the San Francisco Bay Area, the general health and safety recommendations provided by a CIH may include the following:
 Update the site-specific Health and Safety Plan (HASP) to address the presence of NOA at the site.
 Perform NOA worker training for each trade performing activities in or disturbing NOA.

In our experience, training must be conducted for each applicable subcontractor and individual employees working in NOA or with potential exposure to NOA.  Perform a series of negative exposure assessments (i.e., personal air monitoring) for each activity and each subcontractor disturbing NOA (excavation and grading, foundation work, etc.).
 During the initial personal air monitoring, personnel protective equipment (PPE) is typically upgraded to Level C (as determined by the CIH). The CIH will work with the

6 “Construction grading” means any surface disturbance conducted with powered equipment or any related activity, including, but not limited to, all surface and subsurface cuts and fills, excavation, trenching, stockpiling, bulldozing, and landfills.

Preliminary Geotechnical Site Assessment
Gallo Site
South San Francisco, California
Langan Project No.: 770675101
27 October 2020

subcontractors to determine which activities require personal air monitoring. This typically needs to be repeated for each subcontractor and each new activity.  Document acceptable personal air monitoring results below the OSHA permissible exposure limit (PEL) for asbestos, and deescalate PPE to Level D (if monitoring results are below the OSHA PEL) If monitoring results are elevated above OSHA PELs, the CIH will most likely recommend that Level C PPE remain in place until monitoring results indicated acceptable air quality for workers.

A CIH will be able to provide more details on hazard notification and appropriate Cal OSHA compliance requirements. Langan recommends consulting with a CIH before continuing any work in potential areas containing NOA.

6.3 Shoring Considerations
If basements will be constructed, the sides of the excavation can be sloped. We preliminarily conclude temporary slopes in rock should not be steeper than 1:1 (horizontal to vertical); slopes should not be steeper than 1.5:1 in soil.

If there is insufficient space to slope the excavation, adjacent property and streets should be supported by temporary shoring. There are several key considerations in selecting a suitable shoring system. Those we consider to be primary concerns are:
 protection of surrounding improvements, including roadways, utilities, and adjacent structures;
 penetration of shoring supports into stiff clay, dense sand or bedrock;  proper construction of the shoring system to minimize the potential for ground movement; and
 cost.

We conclude a soldier-pile-and-lagging system would be an appropriate shoring system for this project. Soldier piles should be placed in predrilled holes which will be backfilled with concrete or installed with a soil-cement mixing drill rig. Wood lagging should be placed between the soldier beams as the excavation proceeds. Drilling of the shafts for the soldier piles may require casing and/or the use of drilling mud to prevent caving of any sand layers that are present. Alternatively a soil-nail system may be used
Depending on the depth of excavation, lateral restrained may be required, such as tiebacks or internal bracing. Our experience indicates that for a one level basement tiebacks may not be required; however, an excavation for two basement levels would require tiebacks. Tiebacks may require encroachment permits from adjacent property owners. Minor deflections of the ground surface and adjacent structures should be expected with a soldier-pile-and-lagging system. The amount of movement and distress to adjacent improvements will depend on the rigidity of the Preliminary Geotechnical Site Assessment
Gallo Site
South San Francisco, California
Langan Project No.: 770675101
27 October 2020

shoring and the workmanship of the contractor. We estimate a properly installed soldier-pile-andlagging system will limit movement of the top of the shoring wall to less than one inch. If cohesionless layers are encountered, some caving may occur while lagging boards are installed.

To reduce movements and caving, it may be necessary to limit the unsupported height of the excavation to the height of the lagging boards; however, based on the soil encountered in our investigation at the site, we judge this scenario to be unlikely.

The selection, design, construction, and performance of the shoring and underpinning system should be the responsibility of the contractor. A structural/civil engineer knowledgeable in this type of construction should be retained to design the shoring. We should review the final shoring and underpinning plans to check that they are consistent with the recommendations presented in this report.

We preliminary recommend that a cantilevered shoring system be designed to resist an active pressure of 35 pounds per cubic foot (pcf). Passive resistance may be calculated using an equivalent fluid weight of 300 pcf. In calculating these pressures, we have assumed the bottom of the excavation is above the design ground water level or the site will be dewatered to at least three feet below the base of the excavation. The allowable passive pressures may be assumed to act over two soldier-pile diameters, provided the concrete backfill has a strength of at least 200 pounds per square inch (psi). The passive pressures already include a factor of safety of about 1.5.

If two basement levels will be will be excavate tiebacks will be required and we can provide supplemental recommendations as part of a design level geotechnical report.

6.4 Foundation and Settlement
The available subsurface information indicates the subgrade across the proposed development primarily consists of medium dense to very dense sand and shallow bedrock. Considering the subsurface conditions at the site, we judge the most economical foundation systems for the proposed structures are shallow foundation system consisting of individual or continuous footings gaining support in the dense to very dense sand or bedrock. Assuming spread footings are used to support the structures, we estimate total settlement should be about one inch and differential settlement between columns should be about ½ inch. Should there be instances where footings are subjected to uplift loads that exceed the weight of the structure, tiedown anchors may be used to resist the net uplift.

The bottom of the footings should be embedded at least 18 inches below the lowest adjacent soil subgrade and should be at least 18 inches wide for continuous footings and 24 inches for isolated spread footings. However, about 2.5 to 3 feet of fill was encountered in the borings and footing excavations will need to be deepened to bear on native soil or rock. The overexcavations can be backfilled lean or structural concrete to the base of the footings.

The allowable bearing pressure will vary across the site depending on the depth of the foundation and if the foundations are bearing in bedrock or soil. For preliminary design we recommend designing the footings using an allowable bearing pressure of 4,000 to 5,000 pounds per square Preliminary Geotechnical Site Assessment
Gallo Site
South San Francisco, California
Langan Project No.: 770675101
27 October 2020

foot (psf). A one-third increase may be applied to the allowable value for total design loads, which include wind or seismic forces.

Lateral loads on footings can be resisted by a combination of passive resistance acting against the vertical faces of the footings and friction along the bases of the footings. Passive resistance may be calculated using lateral pressures corresponding to an equivalent fluid weight of 300 pounds per cubic foot (pcf); the upper foot of soil or bedrock should be ignored unless confined by a concrete slab or pavement. Frictional resistance should be computed using a base friction coefficient of 0.30. The passive resistance and base friction values include a factor of safety of about 1.5 and may be used in combination without reduction.

6.5 Groundwater Considerations
Any basements and slabs extend into the bedrock or below water will need to be waterproofed and either drained or designed for hydrostatic pressures.

6.6 2019 California Building Code Mapped Values
The western portion of the site is underlain by bedrock and is preliminary classified as Site Class B. The eastern portion of the site is underlain by Colma Formation, which typically consists of dense sand and stiff clay. We preliminary conclude the eastern two-thirds of the site may be classified as Site Class C; however, this will need to be confirmed as part of design level investigation. If eastern portion of the site is classified as Site Class D, then site specific spectra may be required, if the structure(s) do not meet the exceptions in Section 11.4.8 of ASCE 7-16.

For seismic design in accordance with the provisions of 2019 CBC/ASCE 7-16, we preliminarily recommend the following:
 Risk Targeted Maximum Considered Earthquake (MCER) Ss and S1 of 1.849g and 0.757g, respectively;
 Western approximate one-third of site;
o Site Class B,
o Site Coefficients FA and FV of 1.0 and 1.0, respectively, o MCER spectral response acceleration parameters at short periods, SMS, and at one-second period, SM1, of 1.849g and 0.757g, respectively, o Design Earthquake (DE) spectral response acceleration parameters at short period, SDS, and at one-second period, SD1, of 1.233g and 0.505g, respectively,  Eastern approximate two-third of site;
o Site Class C,
o Site Coefficients FA and FV of 1.2 and 1.4, respectively, Preliminary Geotechnical Site Assessment
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o MCER spectral response acceleration parameters at short periods, SMS, and at one-second period, SM1, of 2.219g and 1.060g, respectively, o Design Earthquake (DE) spectral response acceleration parameters at short period, SDS, and at one-second period, SD1, of 1.479g and 0.717g, respectively.

6.7 Design Level Report
The conclusions and recommendations presented in this letter result from limited subsurface investigation and are preliminary. They should not be used to develop final design drawings. We will be performing engineering analysis to develop design level geotechnical recommendations that will be presented in a subsequent report.

Sincerely yours,
Langan Engineering and Environmental Services, Inc.

Peter Brady, P.E. John Gouchon G.E.

Project Engineer Principal
Attachments: References
Figures 1 through 5
Appendix A – Boring Logs
Appendix B – Analytical Laboratory Reports
770675101.04 PJC_Preliminary Geotechnical Site Assessment Preliminary Geotechnical Site Assessment
Gallo Site
South San Francisco, California
Langan Project No.: 770675101
27 October 2020

REFERENCES
ASCE/SEI 7-16 (2016). Minimum Design Loads for Buildings and Other Structures.

Bonilla, M.G. (1998). “Geology Map and Map Database of the San Francisco South, and part of the Hunter Point, San Francisco Bay Area, California.”
California Air Resource Board (2002), Asbestos Airborne Toxic Control Measure for Construction, Grading, Quarrying and Surface Mining Operations.

California Building Standards Commission (2019). California Building Code.

California Department of Conservation Division of Mines and Geology (1997). Guidelines for Evaluating and Mitigating Seismic Hazards in California. Special Publication 117.

California Division of Mines and Geology (1996). Probabilistic Seismic Hazard Assessment for the State of California, CDMG Open-File Report 96-08.

California Emergency Management Agency (2009). “Tsunami Inundation Map for Emergency Planning, Mountain View Quadrangle, State of California, County of Santa Clara.” Cao, T., Bryant, W. A., Rowshandel, B., Branum D. and Wills, C. J. (2003). “The Revised 2002 California Probabilistic Seismic Hazard Maps.”
Idriss, I.M. and Boulanger, R.W. (2008). “Soil Liquefaction During Earthquakes.” Earthquake Engineering Research Institute. Monograph MNO-12.

Langan Engineering and Environmental Services, Inc. (2020). “Geotechnical Investigation, Britannia Modula Labs III, 328 Roebling Road, South San Francisco, California.” Langan Engineering and Environmental Services, Inc. (2020). “Geotechnical Investigation, Forbes Research Center, 494 Forbes Boulevard, South San Francisco, California.” Langan Engineering and Environmental Services, Inc. (2019). “Geotechnical Investigation, Gateway of Pacific Phase 3, South San Francisco, California.” Lienkaemper, J.J. (1992). “Map of recently active traces of the Hayward Fault, Alameda and Contra Costa counties, California.” Miscellaneous Field Studies Map MF-2196.

Seed, H.B. and Idriss, I.M. (1971). “Simplified Procedure for Evaluating Soil Liquefaction during Earthquakes,” Journal of Geotechnical Engineering Division, ASCE, 97 (9), 1249-1273.

Tokimatsu, K. and Seed, H.B. (1987). “Evaluation of Settlements in Sand due to Earthquake Shaking.” Journal of Geotechnical Engineering, Vol. 113, No. 8, pp. 861-878.

Preliminary Geotechnical Site Assessment
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Langan Project No.: 770675101
27 October 2020

REFERENCES
(Continued)
Working Group on California Earthquake Probabilities (WGCEP) (2007). “The Uniform California Earthquake Rupture Forecast, Version 2.” Open File Report 2007-1437.

Working Group on California Earthquake Probabilities (WGCEP) (2003). “Summary of Earthquake Probabilities in the San Francisco Bay Region: 2002 to 2031.” Open File Report 03-214.

Youd, T.L., and Idriss, I.M. (2001). “Liquefaction Resistance of Soils: Summary Report from the 1996 NCEER and 1998 NCEER/NSF Workshops on Evaluation of Liquefaction Resistance of Soils,” Journal of Geotechnical and Geoenvironmental Engineering, Vol. 127, No. 4.

Youd, T.L., and Garris, C.T. (1995). “Liquefaction-induced ground-surface disruption.” Journal of Geotechnical Engineering, American Society of Civil Engineers, Vol. 121, 805-809.

Youd, T.L., Hansen, C.M., and Bartlett, S.F., (2002). Revised Multilinear Regression Equations for Prediction of Lateral Spread Displacement, Journal of Geotechnical and Geoenvironmental Engineering, December 2002.

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© 2019 Langan
Langan Engineering, Environmental, Surveying, Landscape Architecture and Geology, D.P.C.

Filename: \\langan.com\data\SJO\data1\770675101\Project Data\CAD\01\2D-DesignFiles\Geotechnical\770675101-SiteLocMap-FaultMap-MM Scale.dwg Date: 10/22/2020 Time: 08:09 User: agekas Style Table: Langan.stb Layout: Figure 1 Site Loc Approximate scale
0 2,000 Feet
Notes: 1. Site locate d in the San Francisco North U SGS Quadrangle .

2. Topographic base map is provide d through Langan’s Esri Arc GIS software licensing and Arc GIS online ,
National Geographic Society, i-cubed .

SITE

FORBES BOULEVARD

ECCLES AVENUE

CABOT ROAD ALLERTON AVENUE E GRAND AVENUE
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San Jose, CA 95113
T: 408.283.3600 F: 408.283.3601 www.langan.com
© 2020 Langan
Langan Engineering and Environmental Services, Inc.

Approximate location of boring by
Langan, October 2020
Approximate site boundary

EXPLANATION
B-1
Approximate scale
200 400 Feet
Reference: Google Earth 2020.

B-3
B-2
B-1
Filename: \\langan.com\data\SJO\data1\770675101\Project Data\CAD\01\2D-DesignFiles\Geotechnical\770675101-SiteLocMap-FaultMap-MM Scale.dwg Date: 10/23/2020 Time: 10:29 User: agekas Style Table: Langan.stb Layout: Figure 3-GeologyMap 1 Almaden Boulevard, Suite 590
San Jose, CA 95113
T: 408.283.3600 F: 408.283.3601 www.langan.com
© 2019 Langan
Langan Engineering, Environmental, Surveying, Landscape Architecture and Geology, D.P.C.

Base map: Geology Map and Map Database of the San Francisco South, and part of the Hunter point, San Francisco Bay Area, California, by M.G. Bonilla, 1998.

Approximate scale
0 1,200 Feet
--Depositional or intrusive contact,
dashed where approximate located,
dotted where concealed
Contact

EXPLANATION
Qsr Slope debris and ravine fill (Holocene)
Artificial fill (Holocene)
Qal
Artificial fill over tidal flat (Holocene)
KJu
Alluvium (Holocene)
SITE
KJs
1800s --Shoreline and stream channels
Sheared rocks (Cretaceous and Jurassic)
Sandstone and shale interbedded (Cretaceous and Jurassic) KJsk
sp
Sandstone and shale (Cretaceous and Jurassic)
Serpentine (Cretaceous and Jurassic)
Qaf
Qaf/tf
Qc Colma Formation (Holocene)

HILLSIDE FAULT
Filename: \\langan.com\data\SJO\data1\770675101\Project Data\CAD\01\2D-DesignFiles\Geotechnical\770675101-SiteLocMap-FaultMap-MM Scale.dwg Date: 10/22/2020 Time: 07:59 User: agekas Style Table: Langan.stb Layout: Figure 3 FaultMap 1 Almaden Boulevard, Suite 590
San Jose, CA 95113
T: 408.283.3600 F: 408.283.3601 www.langan.com
© 2019 Langan
Langan Engineering, Environmental, Surveying, Landscape Architecture and Geology, D.P.C.

Approximate scale
0 20 Miles
Notes: 1. Quaternary fault data displayed are based on a generalized version of USGS Quaternary Fault and fold database, 2010. For cartographic purposes only.

2. The Earthquake Epicenter (Magnitude) data is provided by the U.S Geological Survey (USGS) and is current through 08/26/2014.

3. Basemap hillshade and County boundaries provided by USGS and California Department of Transportation.

4. Map displayed in California State Coordinate System, California (Teale) Albers, North American Datum of 1983 (NAD83) , Meters.

Magnitude 5 to 5.9
Magnitude 6 to 6.9
Magnitude 7 to 7.4
Magnitude 7.5 to 8
Earthquake Epicenter
Magnitude
LEGEND
County Boundary
Fault
SITE
1 Almaden Boulevard, Suite 590
San Jose, CA 95113
T: 408.283.3600 F: 408.283.3601 www.langan.com
© 2019 Langan
Langan Engineering, Environmental, Surveying, Landscape Architecture and Geology, D.P.C.

Filename: \\langan.com\data\SJO\data1\770675101\Project Data\CAD\01\2D-DesignFiles\Geotechnical\770675101-SiteLocMap-FaultMap-MM Scale.dwg Date: 10/22/2020 Time: 07:57 User: agekas Style Table: Langan.stb Layout: Figure 4 MM Scale I Not felt by people, except under especially favorable circumstances. However, dizziness or nausea may be experienced.

Sometimes birds and animals are uneasy or disturbed. Trees, structures, liquids, bodies of water may sway gently, and doors may swing very slowly.

II Felt indoors by a few people, especially on upper floors of multi-story buildings, and by sensitive or nervous persons.

As in Grade I, birds and animals are disturbed, and trees, structures, liquids and bodies of water may sway. Hanging objects swing, especially if they are delicately suspended.

III Felt indoors by several people, usually as a rapid vibration that may not be recognized as an earthquake at first. Vibration is similar to that of a light, or lightly loaded trucks, or heavy trucks some distance away. Duration may be estimated in some cases.

Movements may be appreciable on upper levels of tall structures. Standing motor cars may rock slightly.

IV Felt indoors by many, outdoors by a few. Awakens a few individuals, particularly light sleepers, but frightens no one except those apprehensive from previous experience. Vibration like that due to passing of heavy, or heavily loaded trucks. Sensation like a heavy body striking building, or the falling of heavy objects inside.

Dishes, windows and doors rattle; glassware and crockery clink and clash. Walls and house frames creak, especially if intensity is in the upper range of this grade. Hanging objects often swing. Liquids in open vessels are disturbed slightly. Stationary automobiles rock noticeably.

V Felt indoors by practically everyone, outdoors by most people. Direction can often be estimated by those outdoors. Awakens many, or most sleepers. Frightens a few people, with slight excitement; some persons run outdoors.

Buildings tremble throughout. Dishes and glassware break to some extent. Windows crack in some cases, but not generally. Vases and small or unstable objects overturn in many instances, and a few fall. Hanging objects and doors swing generally or considerably.

Pictures knock against walls, or swing out of place. Doors and shutters open or close abruptly. Pendulum clocks stop, or run fast or slow.

Small objects move, and furnishings may shift to a slight extent. Small amounts of liquids spill from well-filled open containers. Trees and bushes shake slightly.

VI Felt by everyone, indoors and outdoors. Awakens all sleepers. Frightens many people; general excitement, and some persons run outdoors.

Persons move unsteadily. Trees and bushes shake slightly to moderately. Liquids are set in strong motion. Small bells in churches and schools ring. Poorly built buildings may be damaged. Plaster falls in small amounts. Other plaster cracks somewhat. Many dishes and glasses, and a few windows break. Knickknacks, books and pictures fall. Furniture overturns in many instances. Heavy furnishings move. VII Frightens everyone. General alarm, and everyone runs outdoors.

People find it difficult to stand. Persons driving cars notice shaking. Trees and bushes shake moderately to strongly. Waves form on ponds, lakes and streams. Water is muddied. Gravel or sand stream banks cave in. Large church bells ring. Suspended objects quiver.

Damage is negligible in buildings of good design and construction; slight to moderate in well-built ordinary buildings; considerable in poorly built or badly designed buildings, adobe houses, old walls (especially where laid up without mortar), spires, etc. Plaster and some stucco fall. Many windows and some furniture break. Loosened brickwork and tiles shake down. Weak chimneys break at the roofline.

Cornices fall from towers and high buildings. Bricks and stones are dislodged. Heavy furniture overturns. Concrete irrigation ditches are considerably damaged.

VIII General fright, and alarm approaches panic.

Persons driving cars are disturbed. Trees shake strongly, and branches and trunks break off (especially palm trees). Sand and mud erupts in small amounts. Flow of springs and wells is temporarily and sometimes permanently changed. Dry wells renew flow.

Temperatures of spring and well waters varies. Damage slight in brick structures built especially to withstand earthquakes; considerable in ordinary substantial buildings, with some partial collapse; heavy in some wooden houses, with some tumbling down. Panel walls break away in frame structures. Decayed pilings break off. Walls fall. Solid stone walls crack and break seriously. Wet grounds and steep slopes crack to some extent. Chimneys, columns, monuments and factory stacks and towers twist and fall. Very heavy furniture moves conspicuously or overturns.

IX Panic is general.

Ground cracks conspicuously. Damage is considerable in masonry structures built especially to withstand earthquakes; great in other masonry buildings - some collapse in large part. Some wood frame houses built especially to withstand earthquakes are thrown out of plumb, others are shifted wholly off foundations. Reservoirs are seriously damaged and underground pipes sometimes break.

X Panic is general.

Ground, especially when loose and wet, cracks up to widths of several inches; fissures up to a yard in width run parallel to canal and stream banks. Landsliding is considerable from river banks and steep coasts. Sand and mud shifts horizontally on beaches and flat land. Water level changes in wells. Water is thrown on banks of canals, lakes, rivers, etc. Dams, dikes, embankments are seriously damaged. Well-built wooden structures and bridges are severely damaged, and some collapse. Dangerous cracks develop in excellent brick walls. Most masonry and frame structures, and their foundations are destroyed. Railroad rails bend slightly. Pipe lines buried in earth tear apart or are crushed endwise. Open cracks and broad wavy folds open in cement pavements and asphalt road surfaces.

XI Panic is general.

Disturbances in ground are many and widespread, varying with the ground material. Broad fissures, earth slumps, and land slips develop in soft, wet ground. Water charged with sand and mud is ejected in large amounts. Sea waves of significant magnitude may develop. Damage is severe to wood frame structures, especially near shock centers, great to dams, dikes and embankments, even at long distances. Few if any masonry structures remain standing. Supporting piers or pillars of large, well-built bridges are wrecked.

Wooden bridges that "give" are less affected. Railroad rails bend greatly and some thrust endwise. Pipe lines buried in earth are put completely out of service.

XII Panic is general.

Damage is total, and practically all works of construction are damaged greatly or destroyed. Disturbances in the ground are great and varied, and numerous shearing cracks develop. Landslides, rock falls, and slumps in river banks are numerous and extensive. Large rock masses are wrenched loose and torn off. Fault slips develop in firm rock, and horizontal and vertical offset displacements are notable. Water channels, both surface and underground, are disturbed and modified greatly. Lakes are dammed, new waterfalls are produced, rivers are deflected, etc. Surface waves are seen on ground surfaces. Lines of sight and level are distorted. Objects are thrown upward into the air.

APPENDIX A

BORING LOGS
SILTY SAND with GRAVEL (SM)
gray-brown, moist, fine- to medium-grained,
subangular to subrounded fine to coarse gravel, trace
coarse-grained sand [FILL]

SERPENTINITE
gray-brown, intensely fractured to crushed, low
hardness, friable, deeply weathered [BEDROCK]
gray to gray-brown
SHALE
gray-brown to dark brown, intensely fractured, low
hardness to crushed, moderately hard, plastic to
friable deeply weathered, serpentinite fragments
gray with white discoloration, low hardness
gray-brown, increased serpentinite content

SERPENTINITE
gray-green, closely fractured to crushed, low hardness
to moderately hard, friable to weak, deeply weathered,
white discoloration
gray to gray-green with white discoloration at bottom
with white discoloration
6 5
7 3
4 6
7 13
18 11
50/
4"
17 50/
6"
23 17
23 12
21 50/
2"
12 17
24 14
12 37
60/
4"
60/
6"
48 85/
8"
49 SM
BULK
SPT
SPT
SPT
SPT
SPT
SPT
SPT
SPT
DEPTH
(feet)
Blows/ 6"
SPT
N-Value
1 Sampler

LITHOLOGY
Type
Sample
Type of
Strength
Test
Fines %
Natural
Moisture
Confining
Content, %
Pressure
Lbs/Sq Ft
Shear Strength
Lbs/Sq Ft
Dry Density
Lbs/Cu Ft
See Site Plan, Figure 2
10/19/20
Hollow Stem Auger
Standard Penetration Test (SPT)
Date finished: 10/19/20
Hammer type: Automatic Trip
Boring location:

Date started:

Drilling method:

Samplers:

JDO
Gregg Drilling
Hammer weight/drop: 140 lbs./30 inches
Logged by:

Drilled By:

SAMPLES

LABORATORY TEST DATA
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30

MATERIAL DESCRIPTION
GALLO SITE Log of Boring B-1 South San Francisco, California Figure:
770675101
Project No.:

PROJECT:

A-1
PAGE 1 OF 1
TEST GEOTECH LOG 770675101_GALLOSITE.GPJ TEMPLATE_CA-MODIFIED.GDT 10/23/20 1 S&H and SPT blow counts for the last two increments were converted to SPT N-Values using factors of 0.7 and 1.2, respectively to account for sampler type and hammer energy.

Boring terminated at a depth of 26.5 feet below ground surface.

Boring backfilled with cement grout.

Groundwater not observed at time of drilling.

SILTY SAND with GRAVEL (SM)
gray-brown, moist, fine- to medium-grained,
subangular to subrounded fine to coarse gravel, trace
coarse-grained sand [FILL]
SHALE
gray-brown, intensely fractured to crushed, soft to low hardness, plastic to friable, deeply weathered, white
discoloration [BEDROCK]
light brown to gray-brown with white discoloration
gray-brown
gray-green to gray-brown
gray-brown to light gray, soft to low hardness
low hardness to moderately hard, white discoloration
gray-brown to dark brown with blue-green serpentinite
fragments
8 9
14 7
14 11
11 24
41 24
50/
4"
13 23
29 14
38 36
14 19
50/
2"
15 45
47 28
30 78
60/
4"
62 89
83/
8"
110
SM
GRAB
SPT
SPT
SPT
SPT
SPT
SPT
SPT
SPT
DEPTH
(feet)
Blows/ 6"
SPT
N-Value
1 Sampler

LITHOLOGY
Type
Sample
Type of
Strength
Test
Fines %
Natural
Moisture
Confining
Content, %
Pressure
Lbs/Sq Ft
Shear Strength
Lbs/Sq Ft
Dry Density
Lbs/Cu Ft
See Site Plan, Figure 2
10/19/20
Hollow Stem Auger
Standard Penetration Test (SPT)
Date finished: 10/19/20
Hammer type: Automatic Trip
Boring location:

Date started:

Drilling method:

Samplers:

JDO
Gregg Drilling
Hammer weight/drop: 140 lbs./30 inches
Logged by:

Drilled By:

SAMPLES

LABORATORY TEST DATA
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30

MATERIAL DESCRIPTION
GALLO SITE Log of Boring B-2 South San Francisco, California Figure:
770675101
Project No.:

PROJECT:

A-2
PAGE 1 OF 1
TEST GEOTECH LOG 770675101_GALLOSITE.GPJ TEMPLATE_CA-MODIFIED.GDT 10/23/20 1 S&H and SPT blow counts for the last two increments were converted to SPT N-Values using factors of 0.7 and 1.2, respectively to account for sampler type and hammer energy.

Boring terminated at a depth of 26.5 feet below ground surface.

Boring backfilled with cement grout.

Groundwater not observed at time of drilling.
2 inches asphalt parking log (AC/AB)
Top 5 feet Hand Augered
SAND with SILT (SP-SM)
red-yellow to brown, moist, fine- to medium-grained,
trace coarse particles and clay, moist
increased fines content [FILL]
SAND with SILT (SP-SM)
red-yellow to brown, medium dense, moist, trace dark
brown clay
very dense

CLAYEY SAND (SC)
red-yellow, medium dense, moist, fine- to
medium-grained, trace silt
dense
medium dense, decreased fines content
(10/19/20, 12:35 PM)
red-brown to yellow-brown, wet
SAND with CLAY (SP-SC)
yellow to light brown, very dense, wet, fine- to
medium-grained, trace silt
7 14
28 17
22 22
11 18
26 3
6 6
7 14
14 6
11 13
4 6
7 5
12 20
29 53
53 14
34 29
16 22
SPSM
SPSM
SC
SPSC
GRAB
S&H
SPT
SPT
SPT
SPT
SPT
SPT
S&H
DEPTH
(feet)
Blows/ 6"
SPT
N-Value
1 Sampler

LITHOLOGY
Type
Sample
Type of
Strength
Test
Fines %
Natural
Moisture
Confining
Content, %
Pressure
Lbs/Sq Ft
Shear Strength
Lbs/Sq Ft
Dry Density
Lbs/Cu Ft
See Site Plan, Figure 2
10/19/20
Hollow Stem Auger
Sprague & Henwood (S&H), Standard Penetration Test (SPT) Date finished: 10/19/20
Hammer type: Automatic Trip
Boring location:

Date started:

Drilling method:

Samplers:

JDO
Gregg Drilling
Hammer weight/drop: 140 lbs./30 inches
Logged by:

Drilled By:

SAMPLES

LABORATORY TEST DATA
1 2
3 4
5 6
7 8
9 10
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30

MATERIAL DESCRIPTION
GALLO SITE Log of Boring B-3 South San Francisco, California Figure:
770675101
Project No.:

PROJECT:

A-3a
PAGE 1 OF 2
TEST GEOTECH LOG 770675101_GALLOSITE.GPJ TEMPLATE_CA-MODIFIED.GDT 10/23/20 SAND with CLAY (SP-SC) (continued)
very dense
17 37
50/
3"
61 SPSC S&H
Type of
Strength
Test
Fines %
Natural
Moisture
Confining
Content, %
Pressure
Lbs/Sq Ft
Shear Strength
Lbs/Sq Ft
Dry Density
Lbs/Cu Ft
DEPTH
(feet)
Blows/ 6"
SPT
N-Value
1 Sampler

LITHOLOGY
Type
Sample

SAMPLES LABORATORY TEST DATA
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 50
51 52
53 54
55 56
57 58
59 60

MATERIAL DESCRIPTION
GALLO SITE Log of Boring B-3 South San Francisco, California Figure:
770675101
Project No.:

PROJECT:

A-3b
PAGE 2 OF 2
TEST GEOTECH LOG 770675101_GALLOSITE.GPJ TEMPLATE_CA-MODIFIED.GDT 10/23/20 1 S&H and SPT blow counts for the last two increments were converted to SPT N-Values using factors of 0.7 and 1.2, respectively to account for sampler type and hammer energy.

Boring terminated at a depth of 31.25 feet below ground surface.

Boring backfilled with cement grout - via tremie pipe.

Groundwater observed at 22 feet at time of drilling.

Majo r Divisions Gravels (More than half of coarse fraction > no. 4 sieve size) Sands (More than half of coarse fraction < no. 4 sieve size) Silts and Clays LL = < 50 Silts and Clays LL = > 50 Highly Organic Soils Symbols GWGP GMGCSWSPSMSCML CLOL MHCHOHPT GRAIN SIZE CHART Range of Grain Sizes Classification Boulders Cobbles Gravel coarse fine Sand coarse medium fine Silt and Clay U.S. Standard Sieve Size Above 12" 12" to 3" 3" to No. 4 3" to 3/4" 3/4" to No. 4 No. 4 to No. 200 No. 4 to No. 10 No. 10 to No. 40 No. 40 to No. 200 Below No. 200 Unstabilized groundwater level Stabilized groundwater level Grain Size in Millimeters Above 305 305 to 76.2 76.2 to 4.76 76.2 to 19.1 19.1 to 4.76 4.76 to 0.075 4.76 to 2.00 2.00 to 0.420 0.420 to 0.075 Below 0.075 UNIFIED SOIL CLASSIFICATION SYSTEM Typica l Names Well-graded gravels or gravel-sand mixtures, little or no fines Poorly-graded gravels or gravel-sand mixtures, little or no fines Silty gravels, gravel-sand-silt mixtures Clayey gravels, gravel-sand-clay mixtures Well-graded sands or gravelly sands, little or no fines Poorly-graded sands or gravelly sands, little or no fines Silty sands, sand-silt mixtures Clayey sands, sand-clay mixtures Inorganic silts and clayey silts of low plasticity, sandy silts, gravelly silts Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, lean clays Organic silts and organic silt-clays of low plasticity Inorganic silts of high plasticity Inorganic clays of high plasticity, fat clays Organic silts and clays of high plasticity Peat and other highly organic soils SAMPLE DESIGNATIONS/SYMBOLS Sample taken with Sprague & Henwood split-barrel sampler with a 3.0-inch outside diameter and a 2.43-inch inside diameter. Darkened area indicates soil recovered Classification sample taken with Standard Penetration Test sampler Undisturbed sample taken with thin-walled tube Disturbed sample Sampling attempted with no recovery Core sample Analytical laboratory sample Sample taken with Direct Push or Drive sampler SAMPLER TYPE C Core barrel CA California split-barrel sampler with 2.5-inch outside diameter and a 1.93-inch inside diameter D&M Dames & Moore piston sampler using 2.5-inch outside diameter, thin-walled tube
O Osterberg piston sampler using 3.0-inch outside
diameter, thin-walled Shelby tube
PT Pitcher tube sampler using 3.0-inch outside diameter, thin-walled Shelby tube
S&H Sprague & Henwood split-barrel sampler with a 3.0-inch outside diameter and a 2.43-inch inside diameter SPT Standard Penetration Test (SPT) split-barrel sampler with a 2.0-inch outside diameter and a 1.5-inch inside diameter ST Shelby Tube (3.0-inch outside diameter, thin-walled tube) advanced with hydraulic pressure
Fine -Grained Soils
(more than half of soil
< no. 200 sieve size)
Coarse-Grained Soils
(more than half of soil > no. 200
sieve size Sonic Filename: \\langan.com\data\SJO\data1\770675101\Project Data\CAD\01\2D-DesignFiles\Geotechnical\770675101-B-GI0101_Classification.dwg Date: 10/20/2020 Time: 17:45 User: agekas Style Table: Langan.stb Layout: SOIL CLASSIFICATION REPORT 1 Almaden Boulevard, Suite 590 San Jose, CA 95113 T: 408.283.3600 F: 408.283.3601 www.langan.com © 2019 Langan Langan Engineering, Environmental, Surveying, Landscape Architecture and Geology, D.P.C. 1 Almaden Boulevard, Suite 590
San Jose, CA 95113
T: 408.283.3600 F: 408.283.3601 www.langan.com © 2019 Langan Langan Engineering, Environmental, Surveying, Landscape Architecture and Geology, D.P.C. Filename: \\langan.com\data\SJO\data1\770675101\Project Data\CAD\01\2D-DesignFiles\Geotechnical\770675101-B-GI0101_Classification.dwg Date: 10/20/2020 Time: 17:45 User: agekas Style Table: Langan.stb Layout: Rock Classification

APPENDIX B

ANALYTICAL LABORATORY REPORTS
WorkOrder:

Report Created for: Langan
135 Main St, Suite 1500
San Francisco, CA 94105
Project Contact: Peter Cusack
Project: 770675101; Gallo Site
Project P.O.:

Project Received: 10/19/2020
Analytical Report reviewed & approved for release on 10/21/2020 by:

Christine Askari
2010954
The report shall not be reproduced except in full, without the written approval of the laboratory. The analytical results relate only to the items tested. Results reported conform to the most current NELAP standards, where applicable, unless otherwise stated in the case narrative.

Analytical Report
1534 Willow Pass Rd. Pittsburg, CA 94565 ♦ TEL: (877) 252-9262 ♦ FAX: (925) 252-9269 ♦ www.mccampbell.com CA ELAP 1644 ♦ NELAP 4033 ORELAP
Project Manager
McCampbell Analytical, Inc.
"When Quality Counts"

Glossary of Terms & Qualifier Definitions
Client: Langan
Project: 770675101; Gallo Site
WorkOrder: 2010954
McCampbell Analytical, Inc. 1534 Willow Pass Road, Pittsburg, CA 94565-1701 Toll Free Telephone: (877) 252-9262 / Fax: (925) 252-9269 http://www.mccampbell.com / E-mail: [email protected] "When Quality Counts" Glossary Abbreviation
%D Serial Dilution Percent Difference
95% Interval 95% Confident Interval
CPT Consumer Product Testing not NELAP Accredited
DF Dilution Factor
DI WET (DISTLC) Waste Extraction Test using DI water
DISS Dissolved (direct analysis of 0.45 µm filtered and acidified water sample) DLT Dilution Test (Serial Dilution)
DUP Duplicate
EDL Estimated Detection Limit
ERS External reference sample. Second source calibration verification.

ITEF International Toxicity Equivalence Factor
LCS Laboratory Control Sample
LQL Lowest Quantitation Level
MB Method Blank
MB % Rec % Recovery of Surrogate in Method Blank, if applicable MDL Method Detection Limit
ML Minimum Level of Quantitation
MS Matrix Spike
MSD Matrix Spike Duplicate
N/A Not Applicable
ND Not detected at or above the indicated MDL or RL
NR Data Not Reported due to matrix interference or insufficient sample amount.

PDS Post Digestion Spike
PDSD Post Digestion Spike Duplicate
PF Prep Factor
RD Relative Difference
RL Reporting Limit (The RL is the lowest calibration standard in a multipoint calibration.) RPD Relative Percent Deviation
RRT Relative Retention Time
SPK Val Spike Value
SPKRef Val Spike Reference Value
SPLP Synthetic Precipitation Leachate Procedure
ST Sorbent Tube
TCLP Toxicity Characteristic Leachate Procedure
TEQ Toxicity Equivalents
TZA TimeZone Net Adjustment for sample collected outside of MAI's UTC.

WET (STLC) Waste Extraction Test (Soluble Threshold Limit Concentration)

Glossary of Terms & Qualifier Definitions
Client: Langan
Project: 770675101; Gallo Site
WorkOrder: 2010954
McCampbell Analytical, Inc. 1534 Willow Pass Road, Pittsburg, CA 94565-1701 Toll Free Telephone: (877) 252-9262 / Fax: (925) 252-9269 http://www.mccampbell.com / E-mail: [email protected] "When Quality Counts" Analytical Qualifiers
k10 CARB 435 Exception 1 - No asbestos detected. The limit of quantitation (LOQ) = 0.25%. k15 Chrysotile

Analytical Report
McCampbell Analytical, Inc. 1534 Willow Pass Road, Pittsburg, CA 94565-1701 Toll Free Telephone: (877) 252-9262 / Fax: (925) 252-9269 http://www.mccampbell.com / E-mail: [email protected] "When Quality Counts" Client: Langan
Project: 770675101; Gallo Site
Date Received: 10/19/2020 18:34
Date Prepared: 10/20/2020
WorkOrder: 2010954
Extraction Method: CARB 435 Asbestos
Analytical Method: 435 CARB
Unit: %
Asbestos (CARB 435) 400 Point Count
B-1-3.0 2010954-001A Soil 10/19/2020 08:00 Microscope 207845 Analytes Result RL DF Date Analyzed
Client ID Lab ID Matrix Date Collected Instrument Batch ID Asbestos 3.00 0.25 1 10/21/2020 09:10
Analyst(s): DA Analytical Comments: k15
B-1-7.5 2010954-002A Soil 10/19/2020 08:20 Microscope 207845 Analytes Result RL DF Date Analyzed
Client ID Lab ID Matrix Date Collected Instrument Batch ID Asbestos 1.00 0.25 1 10/21/2020 11:10
Analyst(s): DA Analytical Comments: k15
B-1-12.5 2010954-003A Soil 10/19/2020 08:35 Microscope 207845 Analytes Result RL DF Date Analyzed
Client ID Lab ID Matrix Date Collected Instrument Batch ID Asbestos 0.25 0.25 1 10/21/2020 13:10
Analyst(s): DA Analytical Comments: k15
B-2-5.0 2010954-004A Soil 10/19/2020 10:00 Microscope 207845 Analytes Result RL DF Date Analyzed
Client ID Lab ID Matrix Date Collected Instrument Batch ID Asbestos ND NA 1 10/21/2020 14:15
Analyst(s): DA Analytical Comments: k10
(Cont.)

Analytical Report
McCampbell Analytical, Inc. 1534 Willow Pass Road, Pittsburg, CA 94565-1701 Toll Free Telephone: (877) 252-9262 / Fax: (925) 252-9269 http://www.mccampbell.com / E-mail: [email protected] "When Quality Counts" Client: Langan
Project: 770675101; Gallo Site
Date Received: 10/19/2020 18:34
Date Prepared: 10/20/2020
WorkOrder: 2010954
Extraction Method: CARB 435 Asbestos
Analytical Method: 435 CARB
Unit: %
Asbestos (CARB 435) 400 Point Count
B-2-10.0 2010954-005A Soil 10/19/2020 10:10 Microscope 207845 Analytes Result RL DF Date Analyzed
Client ID Lab ID Matrix Date Collected Instrument Batch ID Asbestos ND NA 1 10/21/2020 15:35
Analyst(s): DA Analytical Comments: k10
B-2-15.0 2010954-006A Soil 10/19/2020 10:15 Microscope 207845 Analytes Result RL DF Date Analyzed
Client ID Lab ID Matrix Date Collected Instrument Batch ID Asbestos ND NA 1 10/21/2020 16:20
Analyst(s): DA Analytical Comments: k10

McCampbell Analytical, Inc.
1534 Willow Pass Rd
Pittsburg, CA 94565-1701
(925) 252-9262
CHAIN-OF-CUSTODY RECORD Page
Lab ID Matrix Collection Date Hold
Requested Tests (See legend below)
Report to:

Peter Cusack
135 Main St, Suite 1500
San Francisco, CA 94105
(415) 955-5244 FAX: (415) 955-9041
PO:
10/19/2020
Client ID
Project: 770675101; Gallo Site
WorkOrder: 2010954
1 of 1
Date Logged:

Date Received: 10/19/2020
1 2 3 4 5 6 7 8 9 10 11 12
Langan
Bill to:

Accounts Payable
Langan
135 Main St, Suite 1500
San Francisco, CA 94105
Requested TAT: 2 days;
ClientCode: TWRF
Email: [email protected]
EDF EQuIS Email HardCopy ThirdParty
Langan_InvoiceCapture@concursolutio
Excel
WriteOn J-flag
cc/3rd Party: [email protected]; [email protected]
WaterTrax
Detection Summary
Dry-Weight
2010954-001 B-1-3.0 Soil 10/19/2020 08:00 A A
2010954-002 B-1-7.5 Soil 10/19/2020 08:20 A A
2010954-003 B-1-12.5 Soil 10/19/2020 08:35 A A
2010954-004 B-2-5.0 Soil 10/19/2020 10:00 A A
2010954-005 B-2-10.0 Soil 10/19/2020 10:10 A A
2010954-006 B-2-15.0 Soil 10/19/2020 10:15 A A
Prepared by: Nancy Palacios
NOTE: Soil samples are discarded 60 days after results are reported unless other arrangements are made (Water samples are 30 days).

Hazardous samples will be returned to client or disposed of at client expense.

Comments:
1 CARB435_400 2 PRDisposal Fee 3 4
5 6 7 8
9 10
Test Legend:
11 12

Lab ID Client ID Collection Date
& Time
Date Logged:

Matrix Test Name Containers TAT
/Composites

WORK ORDER SUMMARY
Work Order: 2010954
Comments:

Client Name: LANGAN Project: 770675101; Gallo Site
QC Level: LEVEL 2
Bottle & Preservative DryWeight Hold SubOut
10/19/2020
Sediment
Content
WriteOn EDF Excel EQuIS Email HardCopy ThirdParty J-flag Client Contact: Peter Cusack
Contact's Email: [email protected]
WaterTrax
McCampbell Analytical, Inc. 1534 Willow Pass Road, Pittsburg, CA 94565-1701 Toll Free Telephone: (877) 252-9262 / Fax: (925) 252-9269 http://www.mccampbell.com / E-mail: [email protected] "When Quality Counts" 2010954-001A B-1-3.0 Soil Asbestos, CARB 435, 400 Point 1 Plastic Baggie, Medium 10/19/2020 8:00 2 days 2010954-002A B-1-7.5 Soil Asbestos, CARB 435, 400 Point 1 Plastic Baggie, Medium 10/19/2020 8:20 2 days 2010954-003A B-1-12.5 Soil Asbestos, CARB 435, 400 Point 1 Plastic Baggie, Medium 10/19/2020 8:35 2 days 2010954-004A B-2-5.0 Soil Asbestos, CARB 435, 400 Point 1 Plastic Baggie, Medium 10/19/2020 10:00 2 days 2010954-005A B-2-10.0 Soil Asbestos, CARB 435, 400 Point 1 Plastic Baggie, Medium 10/19/2020 10:10 2 days 2010954-006A B-2-15.0 Soil Asbestos, CARB 435, 400 Point 1 Plastic Baggie, Medium 10/19/2020 10:15 2 days

- STLC and TCLP extractions require 2 days to complete; therefore, all TATs begin after the extraction is completed (i.e., One-day TAT yields results in 3 days from sample submission).

NOTES:
- MAI assumes that all material present in the provided sampling container is considered part of the sample - MAI does not exclude any material from the sample prior to sample preparation unless requested in writing by the client.

LAMEAM CHAIN OF CUSTODY RECORD Page of,
135 Main Street, Suite 1500, San Francisco, CA 94105 Ph: 415.955.9200/Fax: 415.955.9201 501 14th Street, Third Floor, Oakland CA 94612 Ph: 510.874.4S00/Fax: 510.874.4507 777 Campus Commons Road, Suite 200, Sacramento, CA 95825 Ph: 916.565.7412/Fax: 916.565.7413 Site Name:

Job Number:

Project Manager\Contact:

Samplers:

Recorder (Signature Requ
Gallo Site
770675101 Analysis Requested Turnaround
Peter Cusack/Adam Brown ([email protected])
Langan
435 CARB
Silica eg clean pu-
■o
o
X
Time
48 Hour
ired): No. Containers
Matrix & Preservative
^ Field Sample
Identification No. Date Time Lab Sample No.
o
w
Water Other
_i01
0C/51
CO
0 z1
0)
other
Remarks
B-1 Sample 1 @3' 10/19/2020
o
<
1 X X
B-1 Sample 3 @7.5' 10/19/2020 AM Of'/O 3 X X
B-1 Sample 5 @ 12.5' 10/19/2020 AM 5 X XB-2 Sample 1 @ 5" 10/19/2020 AM m 1 X XB-2 Sample 3 @ 10' 10/19/2020 AM |0|D 3 X XB-2 Sample 5 @ 15' 10/19/2020 AM 101$ 5 X X Relinquished by; (Signature) ^ Date Time
6-^5 J7/W
Receim^ by:-(Signatur&)^ Date Time
Relinquished by: (Signaturdf^ ' (_y Date Time Received by: (SignaCre) ' Date Time 'Relinquished by: (Signature) Date Time Received by Lab: (Signature) Date TimeSent to Laboratory (Name); McCampbell Analytical, Inc Laboratory Comments/Notes: i
Method of Shipment Q^Lab courier Fed Ex |x |Hand Carried| jprivate Courier (Co. Name) Airborne | |UPS go: Peter Brady ([email protected])
^>5 LAjijr^—

1 McCampbell Analytical, Inc.

From: Adam Brown <[email protected]>
Sent: Monday, October 19, 2020 9:52 PM
To: McCampbell Analytical, Inc.; Peter Cusack
Cc: Peter Brady; Jon Oyan; John Gouchon
Subject: RE: WorkOrder Summary for Project: 770675101; Gallo Site [MAI WO#: 2010954] - RUSH
Thank you. Please include Peter Brady, Jon Oyan, and John Gouchon on this work order correspondence.

The sample IDs need to be revised as follows”
2010954-001A = “B-1-3.0”
2010954-002A = “B-1-7.5”
2010954-003A = “B-1-12.5”
2010954-004A = “B-2-5.0”
2010954-005A = “B-2-10.0”
2010954-006A = “B-2-15.0”
Adam Brown, PG
Senior Project Geologist
LANGAN
Celebrating 50 years in business | 1970-2020
Direct: 279.399.8215
Mobile: 415.238.6149
File Sharing Link
www.langan.com

CALIFORNIA NEW JERSEY NEW YORK CONNECTICUT MASSACHUSETTS PENNSYLVANIA WASHINGTON, DC

VIRGINIA OHIO FLORIDA TEXAS ARIZONA COLORADO WASHINGTON

ATHENS CALGARY DUBAI LONDON PANAMA
A Carbon-Neutral Firm | Langan’s goal is to be SAFE (Stay Accident Free Everyday) Build your career with a premier firm. Join Langan.

From: McCampbell Analytical, Inc. <[email protected]> Sent: Monday, October 19, 2020 9:38 PM
To: Peter Cusack <[email protected]>
Cc: Adam Brown <[email protected]>
Subject: WorkOrder Summary for Project: 770675101; Gallo Site [MAI WO#: 2010954] - RUSH Peter,

2 In the event that we cannot deliver a complete, final report within the requested turnaround time, please let us know if you would like a partial report emailed on the due date followed by the final report upon completion by replying to this email. Thank you.

Attached is your Work Order Summary for the above mentioned sample submission for your review. This email is to inform you that your samples have been received and are currently being processed according to the information provided to us on your COC. Please let us know ASAP if you have any corrections &/or additions to this Work Order at this time. Your analytical results and invoice will follow upon completion via email unless otherwise requested on the COC.

Thank you for choosing McCampbell Analytical, Inc. for your analytical needs.

Best regards,
Nancy Palacios
Sample Reception Department
McCampbell Analytical, Inc.
1534 Willow Pass Road
Pittsburg, CA 94565
877-252-9262 (toll free)
925-252-9262 (phone)
925-252-9269 (fax)
[email protected]
www.mccampbell.com
MAI is now open from 8 am to 8 pm, Monday – Friday.

As the situation with COVID-19 continues to develop, MAI knows that our customers and community are being significantly impacted. MAI is closely monitoring the situation and is taking all necessary precautions to ensure the safety of our team members as well as our clients.

This message and or data is intended for the use of the individual or entity to which it is addressed and may contain information that is privileged, confidential, and exempt from disclosure under applicable law. If you are not the intended recipient, you are hereby notified that any use, dissemination, distribution, or copying of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by telephone, and delete this message from your email. Thank You.

This message may contain confidential, proprietary, or privileged information. Confidentiality or privilege is not intended to be waived or lost by erroneous transmission of this message. If you receive this message in error, please notify the sender immediately by return email and delete this message from your system.

Disclosure, use, distribution, or copying of a message or any of its attachments by anyone other than the intended recipient is strictly prohibited.

Sample Receipt Checklist
McCampbell Analytical, Inc. 1534 Willow Pass Road, Pittsburg, CA 94565-1701 Toll Free Telephone: (877) 252-9262 / Fax: (925) 252-9269 http://www.mccampbell.com / E-mail: [email protected] "When Quality Counts" Client Name: Langan
WorkOrder №: 2010954
Date Logged: 10/19/2020
Matrix: Soil Logged by: Nancy Palacios
Carrier: Client Drop-In
Shipping container/cooler in good condition? Yes No
Custody seals intact on shipping container/cooler? Yes No NA Samples Received on Ice? Yes No
Chain of custody present? Yes No
Chain of custody signed when relinquished and received? Yes No Chain of custody agrees with sample labels? Yes No
Samples in proper containers/bottles? Yes No
Sample containers intact? Yes No
Sufficient sample volume for indicated test? Yes No
All samples received within holding time? Yes No NA
Sample/Temp Blank temperature NA
Water - VOA vials have zero headspace / no bubbles? Yes No NA pH acceptable upon receipt (Metal: <2; Nitrate 353.2/4500NO3:
<2; 522: <4; 218.7: >8)?
Yes No NA
Temp: 4.5°C
Chain of Custody (COC) Information
Sample IDs noted by Client on COC? Yes No
Date and Time of collection noted by Client on COC? Yes No Sampler's name noted on COC? Yes No
Sample Receipt Information
Sample Preservation and Hold Time (HT) Information
Sample labels checked for correct preservation? Yes No
Project: 770675101; Gallo Site
(Ice Type: WET ICE )
Comments:
pH tested and acceptable upon receipt (200.8: ≤2; 525.3: ≤4; 530: ≤7; 541: <3; 544: <6.5 & 7.5)?
Yes No NA
UCMR Samples:

Free Chlorine tested and acceptable upon receipt (<0.1mg/L)? Yes No NA Date and Time Received: 10/19/2020 18:34
Received by: Torri Badura
COC agrees with Quote? Yes No NA