GEOTECHNICAL AND HYDROGEOLOGICAL INVESTATION AT FOR THE PROPOSED NEW HIGH RISE CONDOMNIUM AT 6 NOBLE STREET, TORONTO, ONTARIO
The project includes the redevelopment of the subject site with a new 14 storey rental building, with two levels of basement. Based on the available information, the P2 finished floor level will be at about 6.7m below the existing grade, i.e.at about Elevation 87.0m.
Sirati & Partners Consultants Ltd. (SPCL) was retained by Sweeny & Co Architects Inc. to conduct geotechnical, hydrogeological and environmental investigations to provide subsurface information for planning and preliminary design purposes. As part of the investigation program SPCL conducted a “non-intrusive” and “intrusive” investigation by means of drilling boreholes to depths varying from 10.0 to 12.2m below the surface.
The geotechnical aspects cover various elements of design and construction to include (but not limited) to the followings:
- Floor slab and permanent drainage
- Excavations and backfill
- Earthquake considerations
- Earth pressures
- Temporary Shoring
The hydrogeologic investigation consisted of the followings:
- Review of available background information: A review of available geologic and hydrogeological information for the site and surrounding areas
- Detailed site inspection: An inspection of the property for any hydrogeological features such as significant areas of potential ground water recharge or areas of ground water discharge.
- Completion of in situ permeability testing and analyses.
- Assessment of groundwater control requirements. An assessment of the groundwater inflow rates and volumes for the currently proposed design was completed. The information obtained from the rising head tests and soil grain size information was utilized to provide an assessment of the potential ground water control requirements during construction and for the completed structures following construction.
- Completion of groundwater sampling and analysis. Groundwater sampling was completed to identity the groundwater quality. The results of the analysis were used to determine the presence of groundwater contamination and to assess options for disposal of the pumped groundwater.
A hydrogeological report was then prepared for the project to include a summary of the local groundwater conditions in the area has been completed and an evaluation of the proposed construction methods and an assessment of the possible requirements for dewatering or depressurization were completed. Recommendations regarding the estimates of the groundwater control volumes and rates was also provided.