We provide timely engineering geology, geotechnical engineering, and project support services. We believe in conducting thorough evaluations to assess site specific surface and subsurface conditions. While a thorough site specific evaluation can be costly, properly evaluating the site conditions can mitigate the potential for construction-related issues, resulting in substantial project cost savings.
The engineering geology profession focuses on the application of geologic data, techniques, and principles to engineered projects for the purpose of ensuring that geologic factors affecting location, planning, design, and construction are properly recognized, interpreted, and accounted for.
We perform studies to evaluate the existence of active or potentially active faults in areas where proposed developments/improvements are planned. Studies often utilize one or more of the following exploration methods: fault trenching, geophysical surveys, arrays of borings, and review of stereo-paired aerial historical photographs and/or LiDAR imagery. Typically, jurisdictions require evidence supporting surface fault rupture has not occurred in the proposed area of development within the last 10,000 years.
We conduct field mapping and aerial photograph reviews to identify terrain that has or may experience landsliding. We perform subsurface exploration utilizing continuous corings and/or down-hole logging to define landslide geometry and failure surfaces. We use industry-standard software in conjunction with decades of combined experience to evaluate the stability of hillsides and landslides during both static (day-to-day) and earthquake shaking conditions. We can also provide on-going monitoring of landslides or suspect slopes by installing and performing periodic readings of slope inclinometers, piezometers, and/or surface monuments.
Debris flows are geological phenomena in which water-laden masses of soil and fragmented rock rush down mountainsides, funnel into stream channels, entrain objects in their paths, and form thick, muddy deposits on valley floors. In areas of suspect terrain or where prior debris flow events have historically occurred, we perform evaluations to assess the risk for new events, and define anticipated flow velocities and volumes to aid in the engineering of mitigation measures.
We perform rockfall hazard evaluations by conducting field reconnaissance and mapping of exposed rock faces to quantify rock fracture, bedding, and jointing orientations and perform computer simulations of rockfall scenarios to define the probability of rockfalls, bounce heights, and impacts to downslope structures.
We perform studies to evaluate the stability of coastal bluffs subject to slow erosion, toppling from wave scour, and/or deep seated failures. Our coastal project studies also include evaluations of flood hazards, tsunami inundation and wave run-up, and prolonged sea-level rise. Our studies are tailored to develop mitigation and setback recommendations that conform with the design requirements of local jurisdictions and California Coastal Commission guidelines.
SCHOOLS, HOSPITALS, AND ESSENTIAL BUILDINGS
We conduct geologic studies for public schools, hospitals, and essential buildings in compliance with the California Geological Survey Note 48.
The geotechnical engineering profession focuses on the interactions between structural elements with earth materials and processes. Geotechnical engineers use principles of soil and rock mechanics to investigate subsurface conditions and materials at building sites, and apply scientific methods and engineering principles to develop recommendations for the design and construction of engineered structures. Where liquefaction or slope stability hazards our present, we perform our studies in accordance with local jurisdiction requirements and with procedures presented by the California Geological Survey.
We perform studies with a goal of developing recommendations for constructable, cost-effective solutions tailored to the constraints of each project site. For new projects (residential, commercial, municipal, or infrastructure), we perform subsurface investigations and a wide variety of laboratory testing to develop project specific geotechnical engineering recommendations. Our studies for new construction typically include recommendations for one or more of the following: building foundation elements, site and/or basement retaining walls, earthworks, pavement/slab design, site drainage, swimming pools, hazard mitigation elements, or other engineered structures.
Over time, a building's floor can become out of level or a retaining wall can fail due to differential settlement or poor original construction. We perform studies of distressed buildings to evaluate causes and extents of deformation, and develop recommendations for mitigating further distress. These studies typically involve performing floor level surveys, crawlspace and/or drainage inspections, and subsurface exploration. Remediation options may include full or partial foundation underpinnings, retaining wall repairs or replacements, upgrades to site drainage systems, and/or ground improvement.
Expansive Soil Mitigation and Ground Improvements
Sometimes subsurface materials beneath a site may not be suitable for conventional foundations systems. Expansive and/or collapsible soils or other materials of low bearing strength often require mitigation measures or ground improvement methods in order to safely support building loads and conventional foundation construction. Recommendations are based upon the results of specialized laboratory testing and local expertise/experience with the subsurface materials in the area of the project.
Slopes can become unstable due to natural and/or man made causes. We evaluate the stability of slopes by creating a cross-section of the slope based on field mapping, deriving the properties of soil and/or rock beneath the slope using laboratory testing results and published information, and then performing mathematical modeling on industry standard software to interpret the slope's likeliness for movement. We also model different slope instability mitigation methods to develop site-specific recommendations for mitigating future slope movements.
Liquefaction and Lateral Spreading
Liquefaction is the temporary transformation of soil from a solid to a liquefied state during a cyclic loading event such as an earthquake. Lateral spreading is a phenomenon in which surficial soil displaces by gravity or earthquake shaking along a slip surface that forms within an underlying liquefied layer. By analyzing the engineering properties of the earth materials and the groundwater conditions that underlie a site, we can determine if those materials are prone to liquefaction or lateral spreading, and develop recommendations to mitigate or accommodate these hazards.
Plan Review and Construction Observation
Once your designers (i.e. structural engineer, civil engineer, architect, etc.) have completed their project plans, we should review those plans to assess whether our recommendations have been incorporated in to the project design. During construction we provide a wide variety of observation services and testing to document: engineered fill compaction, keyways and benches, driled piers, helical piers, footings, retaining walls, basement excavations, tiebacks, asphalt, concrete slabs-on-grade, flatwork, and drainage provisions.
We provide geologic and/or geotechnical engineering services to assist owners, lawyers, buyers, developers, and other professionals and aid their analysis or decision making process with respect to geologic or geotechnical site conditions.
We provide preliminary on-site consultations where an initial understanding of geologic or geotechnical conditions would aid an interested party in determining a course of action.
REAL ESTATE TRANSACTIONS
We conduct pre-purchase evaluations of buildings or vacant properties for prospective buyers, or pre-sale evaluations for sellers.
As licensed geotechnical engineers, civil engineers, hydrogeologists, engineering geologists, and professional geologists, we can support multiple facets of the litigation process. We are experienced in construction defect, ground deformation or settlement, slope instability, and hydrogeologic analysis.
We have experience performing independent peer review assessments for individuals as well as large firms to aid with the permit process, remediation process, or legal proceedings.
We are experienced in preparing geologic and geotechnical engineering assessments for the preparation or review of environmental impact reports.
Project Spotlight – January 2021 – Masonic Homes of California, Union City Campus
C2Earth, Inc. is excited to be part of the team for improvements to the Masonic Homes campus in Union City, California. Current improvements include: constructing a new Assisted Living and Memory Care building, new site retaining walls, sidewalks and walkways, parking areas, and improvements to site drainage and landscaping elements. The project is well underway, and will result in increased levels of care and enjoyment for the campus occupants.