Blasting at the Central Library Site
As part of the Central Library construction excavation activity, HRM’s contractor will conduct blasting beginning on Tuesday, September 20th on the site at the corner of Spring Garden Road and Queen Street. The work is expected to take two weeks and will not take place on weekends.
Background
The tender package for excavation activity on the Central Library site allowed for vendors to incorporate blasting activity into their excavation plan. The objective was to have bids be as efficient as possible in terms of both cost and time.
The successful bidder, Dexter Construction, will use a combination of traditional rock breaking methods combined with blasting. The blasting itself will take approximately two weeks beginning on September 20th.
Blasting is a safe and well regulated practice requiring a permit issued by HRM that complies with HRM’s blasting bylaw (B-600). The Central Library project team will work closely with the contractor, community groups and neighbours to ensure that blasting procedures are well-understood and that residents feel safe and informed during this time.
How it works
Before a blasting permit can be issued, a pre-blast survey must be conducted on all buildings within a 68 metre radius of the edge of the blast line which is considered to be roughly from the site fence. The survey is conducted by an independent consultant and includes a recorded inspection of both the interior and exterior of the buildings.
Property and business owners within a 300 metre radius of the site will receive a notification letter explaining the timing and conditions that will be in effect during the blasting period of approximately two weeks.
What you’ll see
The contractor will use two drills on site to create space to insert the explosives. It is expected that there will be two to three blasts per day. Preceding each blast, pedestrian and vehicle traffic will be stopped within a safety zone. Traffic control personnel will be in place stopping pedestrians and drivers for three to five minutes at a time.
Each blast charges 15-20 drill holes. Before each charge, you will hear three long horn notifications. Once the blast is complete, one long horn notification will indicate that all is clear.
Those in the area will hear the blast and may feel slight vibrations.
Monitoring
- Blasting is by permit issued by HRM and complies with HRM’s blasting bylaw and Provincial and Federal regulations.
- Seismic and sound levels are outlined in the bylaw. Each blast is monitored, recorded and documented by an independent consultant. Those recordings are reported to HRM officials.
- Explosives are stored at a depot and transported to the site daily. Unused explosives and discarded explosive storage containers are taken off site daily at the completion of work.
