Background

As part of the Provincial Government’s mandate to diversify its renewable energy sources, the Greenwich Lake Wind Farm Project represents Northwestern Ontario’s first ever major wind energy project. The site is located approximately 75 kilometers northeast of the city of Thunder Bay, Ontario. Upon completion of the project, a total of 43 wind turbines will be present at this site. They will generate approximately 100 megawatts (MW) of electricity, enough clean, renewable energy to power around 30,000 typical Canadian homes every year.

TBT Engineering’s Role

Tasks included preliminary geotechnical investigations and exploration, intervisable control establishment surveys, materials testing, field services, and an extensive geotechnical drilling program.

Geotechnical Investigation

Tasks included geophysical investigations, geotechnical sampling and bedrock coring, ground-water monitoring, and the measurement of electrical and thermal resitivities. Geotechnical engineering recommendations were then developed and included topics such as ultimate bearing pressures, depth to founding strata, anticipated constructability issues, soil backfill requirements,  potential for reuse of excavated soils, and rock anchor design parameters.

Geotechnical Drilling

All necessary drilling was completed using our in-house drilling department. Hollow stem augers facilitated soil sampling and down hole testing. Diamond core drilling was used to sample bedrock.

Intervisable Control Establishment Surveys

Control Surveys were completed for approximately 22.5 kilometres of road situated north of Dorion, Ontario. Trimble Series 3 R8 RTK Sur-vey Grade GPS Systems were used, control points were established and related information, along with detailed site plans, were provided.

Materials Testing – Laboratory

An extensive laboratory testing program was undertaken and included testing for moisture content, grain size analyses, and plasticity. Other tests such as compression or point load testing where used for concrete and bedrock.

Field Services

TBT Engineering performed hundreds of field compaction tests and also completed all concrete quality testing. Subgrade inspections were completed to verify the suitability of materials for foundation bearing.