July 2, 2008

Safety

New tunnel safety regulations opposed by British Columbia unions

Prevalence of tunnel boring no cause for less vigilance

RICHARD GILBERT

staff writer

Two groups representing unionized construction workers in British Columbia are voicing their opposition to proposed changes to safety regulations for tunnelling.

The WorkSafeBC proposal would remove some of the province’s safety regulations, if a tunnel boring machine (TBM), or cut and cover methods, are used for underground work.

“We disagreed with the amendments to Part 22, particularly changes relating to the TBM,” said Sheila Moir, director of occupational health and safety at the B.C. Federation of Labour.

“As far as we are concerned, an increasing workload at WorkSafeBC is not a legitimate reason to make changes to the regulations.”

WorkSafeBC is proposing the changes because of the increased use of TBMs.

It argues that the use of TBMs and cut and cover techniques eliminates and lowers some of the hazards related to the traditional drill and blast techniques.

The proposed amendments to Part 22, Underground Workings of the Workers Compensation Act, are intended to address the use of the TBM and a corresponding increase in the administrative workload of employers and WorkSafeBC.

According to the safety regulator, the processing of variance/acceptance requests related to Part 22 is an industry-wide issue and should be considered for change.

The B.C. and Yukon Territory Building and Construction Trades Council (BCYT-BCTC) questions the reasoning behind the proposed changes.

“This is an industry driven proposal for changes,” said Wayne Peppard, executive director of the BCYT-BCTC. “I suggest that it is an offshore industry driven effort to cut the costs related to underground workings.”

Part 22 of the regulations is based on the “drill and blast” excavation technique, which is considered high risk due to high levels of dust, hazards related to using explosives and gases entering the space from the surrounding rock or soil.

“While some of the amendments proposed to Part 22 do not increase safety risks, most of the proposals would enable exceptions that will increase the chance of fatalities and injuries in tunnel construction,” said the trades council in their submission to WorkSafeBC.

“We oppose the exceptions proposed under the designation of Limited Hazard Underground Workings.”

The assumption that the TBM is a safer way to excavate and build tunnels is also being questioned by a group representing many of B.C.’s construction unions.

“Yes, the regulations were written for drill and blast techniques, but, the TBM and the cut and cover technique are not less hazardous. They just created another set of risks for workers,” Moir said.

According to her, there is no place in the world that has made regulatory exceptions for the tunnel boring and cut and cover techniques. If these amendments are approved, WorkSafeBC will be the first one to do it.

Moir and Peppard suggest that WorkSafeBC take a look at a recent cave-in on a TBM project in North York, Ont. to understand the hazards of water and water seepage.

In this incident, six workers for the joint McNally/Aecon venture were digging a segment of York Region’s Big Pipe sewer line. There was a massive water break at the head of the TBM and waterlogged soil suddenly came pouring into the tunnel. Fortunately, the workers were able to run 1.8 kilometres to the entry point of the tunnels to escape.

The machine was completely covered and will have to be salvaged from the tunnel. Another major hazard to workers is changing geology, which can be seen at the Seymour-Capilano water filtration project.

The construction of two tunnels has been delayed since January due to safety concerns.

The TBM ran into unstable rock, which started fracturing and breaking out.

The labour federation said in their submission that this technique may provide workers with a greater protection from falling rocks, but there are still hazards related to gases, radiation and collapse.

The submissions are currently being reviewed.

“All of the submissions made in written form or in person are summarized and analyzed by WorkSafeBC and a report is made to the board of directors,” said Donna Freeman, manager of public affairs with WorkSafeBC.

“The report on Part 22 is not yet on the agenda for the board of directors.”

Both groups recommend that WorkSafeBC carry out another round of consultations to review information from workers with first hand experience at underground workings.

Print | Email | Comment