Geotechnical and Environmental Strategy | Subsurface Investigation and Construction Inspections

Verdantas' initial involvement with the project consisted of performing a geotechnical and environmental subsurface investigation in combination with a Phase I Environmental Site Assessment.  Our versatility in providing geotechnical and environmental services, in addition to our local presence and knowledge of historic conditions throughout the City of Manchester, were valuable resources for our client.  Our versatility was further displayed through our design and construction involvement, which included foundation design, environmental soils characterization and management, and construction inspection services.

Achievements

SUBSURFACE INVESTIGATIONS – Multiple phases of subsurface investigations were necessary for geotechnical design and environmental characterization due to complex conditions resulting from the historically-developed nature of the site. Verdantas used multiple drilling methods to complete the investigations based upon the conditions that included the presence of urban fill, lead-contaminated soil, buried obstructions, sloping bedrock, and other challenging features, including rotary and drive-and-wash drilling, air hammer drilling, and test pits.

GEOTECHNICAL DESIGN – The project included constructing a new multi-story hotel and a two-level parking deck. Verdantas evaluated the differing structural requirements of the two structures and designed a foundation system consisting of drilled micropiles for supporting the hotel and a subgrade reinforcement method for supporting the garage.  Verdantas' consideration of the design requirements of these structures and our experience with numerous foundation systems allowed for cost effective foundation systems to be implemented.  The selected foundation systems also considered environmental conditions at the site and the benefit of minimizing excess soil generation that would require costly off-site disposal.

CONSTRUCTION INSPECTIONS – Verdantas provided numerous construction inspection services that dovetailed with our geotechnical and environmental expertise. Our ability to provide simultaneous inspections benefited the project by providing (many times) a single engineer/scientist for both geotechnical and environmental inspections, which allowed for reliability, fluidity, and cost savings.

Scope of Services

• Phase I ESA
• Geotechnical Investigation
• Environmental Investigation and Soil Characterization
• Foundation Design
• Cost/Feasibility Study
• Environmental Soils Management Cost Estimating
• Soil Management Plan
• Preconstruction Survey
• Coordination of Soil Excavation and Off-Site Disposal
• Construction Inspections:
  • Micro pile installation
  • Foundation subgrade preparation
  • Soils compaction testing
  • Concrete testing
  • Dust monitoring