VANCOUVER -- Both sides in the fracking debate in British Columbia say a new study in the U.S. backs their position.

A major study from the U.S. Environmental Protection Agency — in the works for five years — found hydraulic fracturing activities in the United States have not led to widespread, systemic effects on drinking water.

However, the draft report said that fracking can lead to contamination, including through spills of hydraulic fluids and waste water, and inadequate protection of wells with metal casings and concrete.

The study outlines several examples of drinking water being affected, but noted these were small compared to the large number of wells. About 25,000 to 30,000 oil and natural gas wells are fracked each year in the U.S.

Contamination of drinking water has been one of the key worries raised about fracturing on both sides of the border.

The issue often elicits emotional reactions and gaining significant public attention in films such as Gasland in the U.S., and in the B.C.-film Fractured Land.

The fracking process involves pumping a mixture of water, sand and chemicals deep underground at high pressure to fracture rocks, allowing the trapped natural gas to flow and then be pumped to the surface.

The industry has long said there are no examples of water contamination from more than 215,000 fracked wells in Western Canada.

Fracking of natural gas wells in northeastern B.C. could increase significantly if one or more liquefied natural gas export plants on the coast of B.C. go ahead. No projects — including those led by companies such as Petronas, Shell and Chevron — have made a final investment decision.

Many provinces in Eastern Canada have moratoriums on fracking until more study is done, including Quebec, New Brunswick, Nova Scotia and Newfoundland.

“To me, the report … is about making sure we are on top of regulatory best practices — and ensuring there is good enforcement across the sector — and that’s something that is never (finished),” said Matt Horne, a B.C. regional associate director for the Pembina Institute.

Horne said the bigger issue is the cumulative effect of fracking, potentially thousands more wells, and the roads and pipelines that connect them. “That is really the scenario that hasn’t been explored in enough detail in B.C.,” he said.

The institute, which advocates transitioning to a clean-energy economy, has opposed fracking pending more scientific study.

Geoff Morrison, spokesman for the Canadian Association of Petroleum Producers, said the study should provide assurances to the public in Western Canada, particularly as industry believes regulation and oversight is more robust here than in the U.S.

“People should feel confident that if this process is done right … it’s safe for people and the environment,” said Morrison, who is based in Victoria.

There were several findings particularly relevant to British Columbia.

The EPA report, which reviewed 950 source of information, noted that a modelling study in North Dakota showed that leaks from inside a well to the drinking water sources decreased by a factor of about 1,000 when metal tubes protected the fracking well to below the level of underground drinking water sources.

In British Columbia, regulations require that such tubes or a concrete lining must be extended below drinking water sources.

The study also found that fractures in deep formations kilometres below the surface — which is what takes place in northeast B.C. — are unlikely to extend upward from these deep formations into the shallow drinking water aquifers.

The study did note limitations such as inadequate baseline information on water quality and a lack of scientific information on the effects of chemicals used in fracking on drinking water sources.

ghoekstra@vancouversun.com

Click here to report a typo or visit vancouversun.com/typo.

Is there more to this story? We'd like to hear from you about this or any other stories you think we should know about. CLICK HERE or go to vancouversun.com/moretothestory