A few kilometres from Ken Summers's home, a stout pipe bristling with rusty valves and thick bolts protrudes from the middle of a cleared field.

Summers says it represents the beginning of a potential environmental nightmare for Nova Scotia.

The device is a wellhead. It sits atop an exploratory natural gas well drilled in 2008 by Elmworth Energy, Canadian subsidiary of Denver-based Triangle Petroleum Corp.

Summers, a carpenter who has lived in Minasville, N.S., for 20 years, says he and his neighbours weren't concerned about the test well until they started learning more about hydraulic fracturing, the extraction process used on at least two of the company's five test wells east of Windsor, N.S.

"The industry does thousands of wells wherever there's a major producing field," Summers says, noting that the wells are now idle. "It would be like living in an industrial zone plopped down in a place that was previously quite rural."

Hydraulic fracturing, or fracking, involves blasting a mixture of water, sand and chemicals into a well bore to fracture the surrounding rock and release the trapped hydrocarbons, usually natural gas, coalbed methane or crude oil.

Critics say the process threatens drinking water supplies by allowing the migration of noxious gases and chemicals into the water table.

"Most of the drilling fluids stay where they're intended to be, but it doesn't always work that way," Summers says.

The industry says the process is safe, noting that over a million wells have been fracked since the 1940s.

In Canada, at least 175,000 wells have been fracked, the majority of them in Alberta. The industry is also well-established in British Columbia and Saskatchewan, and exploration is rapidly expanding in almost every other province.

While there have been news reports of contaminated wells, accidents and safety infractions in the United States, industry representatives say the relatively small number of high-profile cases are getting undue attention.

The industry also argues that it's wrong to compare the shallow wells in some U.S. states with the much deeper wells in Canada.

But industry critics say it's wrong to compare the older fracturing process with so-called high-volume hydraulic fracturing used on shale deposits -- a process that has grown in popularity since the 1990s. The newer process, they say, has a much bigger impact on the environment, especially when things go wrong.

Last month, the U.S. Environmental Protection Agency announced for the first time that fracking may be to blame for causing groundwater pollution. The agency found compounds likely associated with fracking chemicals had been detected in the groundwater beneath Pavillion, Wyo., where residents say their well water reeks of chemicals.

Environmentalists characterized the report as a significant development though it met immediate criticism from the oil and gas industry. Calgary-based Encana Corp., which owns the Pavillion gas field, has suggested the chemicals may not be related to gas development.

In New Brunswick, citizen groups and environmentalists opposed to fracking have been blocking roads and staging demonstrations at public meetings and government buildings.

Despite the public outcry, the industry is rapidly moving ahead in the province.

Of the 49 wells that have been fracked in New Brunswick in recent years, 30 are already in production, the provincial government says. However, the government says only three shale gas test wells have been drilled in the province, two of which it considers in the same league as the shale gas wells that are attracting attention in the United States.

Last month, a petition with 16,000 names was presented in the New Brunswick legislature. The document calls on Tory Premier David Alward to abandon plans for development of the shale gas industry, which typically requires large quantities of water and horizontal drilling.

The issue is a particularly thorny one for Alward, who won a majority government last fall by promising to consult the public ahead of making major decisions, such as the previous government's botched bid to sell NB Power, the province's public utility company, to Hydro-Quebec.

"The government needs to hit the pause button here," says Liberal Opposition leader Victor Boudreau, who wants a moratorium on development until the public is consulted.

But Alward has made it clear he is convinced shale gas development under stringent regulations would be good for a province with the third-highest unemployment rate in the country.

"I would love to see more young people in New Brunswick or more New Brunswickers in general being able to work here ... instead of having to go to other parts of Canada," he said in an interview.

Mike Amos, an anti-fracking protester from Doaktown, N.B., says the cash-strapped province doesn't have the resources to properly monitor the emerging industry.

"It would cost at lot of money at a time when the province is trying to cuts costs on everything," he says.

Another protester, Louise Melanson of Fredericton, says the NB Power debacle should serve as a warning to Alward.

"We've learned to organize," she says. "We've learned to stand tall and pull together."

Kevin Heffernan, vice-president of the Calgary-based Canadian Society for Unconventional Resources, says the energy industry is responding to public concerns.

"That's one of the things that the very visible public apprehension has done: it's pushed the industry to take a look at itself," he says.

However, Heffernan says the industry is being forced to put out fires it didn't start. Many of the high-profile cases involving contamination of groundwater, he says, can be traced to poor well construction, not the fracturing process itself.

"I don't think any operator sets out to cut corners and put aquifers at risk," he says.

As for Eastern Canada, Heffernan admits the industry has a challenge on its hands.

"The public, for the most part, is very unfamiliar with the industry," he says.

"This is very, very early days in New Brunswick and Nova Scotia. There's time to build an appropriate set of regulations."

In Nova Scotia, environmentalists say the provincial government's decision in April to launch a review of the industry's best practices does not go far enough. Some critics are calling for a strategic environmental assessment, a comprehensive process that can take years to complete.

Heffernan says his organization is not opposed to the environmental review process -- so long as exploration and development is not held up by a moratorium.

"It would create a level of transparency," he says.

Nova Scotia's review is expected to be complete in March.

Even though only two wells have been fracked in Nova Scotia, an umbrella group opposed to the process -- the Nova Scotia Fracking Resource and Action Coalition -- has attracted 50 environmental groups and individuals.

Jennifer West, the group's chairwoman, says opposition to fracking gathered steam after the release last year of "Gasland," a disturbing documentary that focuses on the town of Dimock, Penn., where residents have complained that shale fracking has transformed their drinking water into a putrid, flammable mess.

West, groundwater co-ordinator with the Halifax-based Ecology Action Centre, says the province should follow Quebec's lead and launch a thorough environmental review of fracking.

In March, the Quebec government bowed to public pressure and suspended commercial fracking until public consultations have been completed.

Quebec is home to one of the largest shale formations in North America, and supporters of the industry say it could deliver $1 billion in annual royalties to the province, generating between 5,000 and 19,000 jobs.

At least 30 test wells have been drilled in Quebec since 2008.

West says an environmental assessment is also needed in Nova Scotia, along with a 10-year moratorium on exploration and development.

"If the government decides that shale gas development will occur, we want it to be done as safely as possible."

West says the province has done the right thing in the past, having called for a full environmental assessment before approving experiments with tidal energy in the Bay of Fundy.

"The temptation is to get in there really fast and exploit it as fast as possible," she says. "But the rock isn't going anywhere. There should be no rush to develop this resource."

In April, P.E.I.'s Liberal government said fracking will not get approval without an environmental assessment and public consultations.