GO Transit is in breach of its obligation under section 95.1 of the Canada Transportation Act to cause only such noise and vibration as is reasonable, in relation to GO Transit's pile-driving activities at the West Toronto Diamond. The Agency found that, in the circumstances, the prolonged exposure of the local citizens to the noise and vibration generated at that location is unreasonable.
The Agency's proposed measures are:
- Vibratory hammer:
Use a vibratory hammer to completely install the piles by modifying the hammer's frequency settings and, where this is not possible, drive the piles to the maximum depth possible considering soil conditions and then finish the pile-driving with an impact hammer.
- Giken hammer:
Extend the use of the Giken hammer in conjunction with vibratory hammer use, as discussed in the Decision, for the entire length of pile-driving activities and not just until the scheduled 250 piles are installed, especially in the more sensitive areas.
- Impact hammer and related mitigative measures:
a) Use an impact-vibration hammer which switches automatically from one mode to another depending on soil resistance. Alternatively, use the impact hammer on the project only in conjunction with a vibratory or Giken hammer and only where it has been demonstrated that no other method is technically or commercially feasible;
b) De-power the impact hammer and decrease the hammer energy wherever possible and use shrouds, skirts and rubberized chasers. Any opening in the shroud should always be positioned down the tracks and not toward any residential area;
c) Employ moveable noise barriers to deflect noise away from nearby residential areas by moving them to current pile-driving locations and by setting them up around the shrouds to deflect noise from the fourth, open side of the shroud.
- Limited hours for pile-driving activities:
a) Restrict the hours of work for installing piles to 40 hours per week from between 8:00 a.m. and 4:00 p.m. on weekdays;
b) Negotiate an agreement with the City of Toronto to allow for road closures during the weekday hours to complete the required work at that location between 8:00 a.m. and 4:00 p.m. on weekdays;
c) Negotiate agreements with other railway companies to allow for train blocks during the weekday hours to complete the required work at that location between 8:00 a.m. and 4:00 p.m. on weekdays.
Information on the Agency's process for dealing with rail noise and vibration complaints is contained in its Guidelines for the Resolution of Complaints Concerning Railway Noise and Vibration.
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