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geotechnical tests on Yonge > Jul-Aug 2009

What is a geotechnical investigation?

A geotechnical investigation involves the collection and testing of soil samples. As part of the Conceptual Design Study for the proposed Yonge Subway extension, we need to determine what the ground conditions are along the proposed subway alignment. When the project receives funding, this will inform future design and costing decisions associated with materials, construction methodology, and tunnel depth.

Drilling will occur at predetermined locations along the alignment and will take soil samples at varying depths. Two borehole drilling machines will be working in parallel to expedite the schedule. Samples collected from the boreholes will be tested to determine their physical properties.

Where will this work be done?

The work is being done along Yonge Street from Steeles Avenue to High Tech Road. The majority of the boreholes are off the travelled portion of the road. However, there are two locations where the work will be located in the roadway and will require lane restrictions on Yonge Street. Additionally, there are three locations which are in close proximity to the road and may impact traffic flow.

When will this work be done?

Working from the south end to the north end, soil samples will be taken from 12 locations along Yonge Street over five weeks (see chart below), from 9:30 am – 3:30 pm.

Who is doing this work?

SPL Consultants Limited is conducting the investigations.

addendum to the Environmental Project Report for the Yonge Subway Extension


December 5, 2014 update

On November 12, 2014 the Ministry of the Environment and Climate Change’s Environmental Approval Branch Director issued a letter indicating that the proponents may proceed with the changes to the Yonge Subway Extension project in accordance with the Environmental Project Report (EPR) Addendum.

The Director’s letter comes after the release of the EPR Addendum for a 30-day public comment period (ended October 6, 2014) followed by a 35-day period (ended November 10, 2014) for the Ministry of the Environment and Climate Change to review the public comments. As a result of the public comment period, the following documents were prepared by the proponents:


York Region Rapid Transit Corporation, in partnership with The Regional Municipality of York, Toronto Transit Commission, and City of Toronto have undertaken an Addendum to the Environmental Project Report [EPR] for the Yonge Subway Extension project that was approved by the Minister of the Environment on April 29, 2009.

In spring 2013, public consultation sessions were held to present the proposed amendments to the Yonge Subway Extension infrastructure, including an underground train storage facility and aboveground buildings, in the Yonge Street and Bantry Avenue area in Richmond Hill.

At these meetings, the preferred location and design concepts of the proposed facility were also presented. Based on the public feedback received, design elements and construction impacts have been further analyzed, mitigation strategies have been identified and revisions have been made to the proposal.

The revised plans for these facilities have been prepared and an addendum to the Environmental Project Report for the Yonge Subway Extension was made available for a 30-day review period, starting September 5, 2014 [see link below], as well as at the locations listed below.

Ministry of the Environment and Climate Change Ministry of the Environment and Climate Change The Regional Municipality of York
Central Region Office Environmental Approvals Access and Service Integration Branch Regional Clerk
5775 Yonge Street, 8th Flr 2 St Clair Ave W., Floor 12A 17250 Yonge Street, 4th Flr
North York, ON  M2M 4J1 Toronto, ON  M4V 1L5 Newmarket, ON  L3Y 6Z1
Phone: 416-326-6700 Phone: 416-314-8001 Phone: 905-830-4444
City of Vaughan Town of Richmond Hill City of Markham
Office of the City Clerk Office of the Town Clerk Office of the City Clerk
2141 Major Mackenzie Dr. 225 East Beaver Creek Road 101 Town Centre Blvd.
Vaughan, ON  L6A 1T1 Richmond Hill, ON  L4B 3P4 Markham, ON  L3R 9W3
Phone: 905-832-8504 Phone: 905-771-8800 Phone: 905-475-4744


If you have any questions, please email us at

notice of EPR Addendum

Environmental Project Report Addendum (full report)


cover page and table of contents

section 1

section 2

section 3

section 4

section 5

section 6


appendix A

appendix B

appendix C

appendix D-1 and appendix D-2

appendix E

appendix F

appendix G

appendix H

appendix I

appendix J

appendix K

past meetings