Researchers at the University of New Brunswick say shale-gas fracking should not proceed in the province unless there is an environmentally sound option for the disposal of waste water that is a by-product of the process.
Four professors at the school released an opinion paper Monday that examines the potential impact on the province's water resources if gas exploration companies begin fracking for shale gas.
They say companies should not be allowed to frack until the saline-contaminated waste water that is forced out of wells can be disposed of in an environmentally responsible manner.
"If groundwater becomes contaminated, it takes years to decades to try to clean up an aquifer system," earth sciences professor Tom Al said Monday. "The best approach is prevention."
The study said conventional water treatment is not able to remove the high concentrations of salts and other toxic and biologically disruptive compounds that are generated in waste water derived from fracking.
The professors said waste water can be recycled, disposed of at proper sites, or in some cases pumped deep underground into saline aquifers. But Prof. Al said it's unclear whether that latter option would be available in New Brunswick because of the province's geology.
The professors suggest that companies should consider using carbon dioxide or liquefied propane gas for fracking instead of water.
"You eliminate all the water-related issues that we're raising, and that people have raised in general across North America," Prof. Al said.
Annie Daigle, a water specialist with the province's Natural Resources Department, said liquefied propane gas has been used to frack some wells in New Brunswick already, but it's not the best choice in every case because of the province's geological makeup.
"It has been used successfully by Corridor Resources here in New Brunswick for lower-volume hydraulic fracturing operations, but it is still a fairly new technology," Ms. Daigle said.
According to the department, three test wells for shale gas were drilled in New Brunswick between 2008 and 2010 and all three were fracked. A fourth such test well was drilled in late 2011 but has not been fracked.
In all, there have been 82 gas wells drilled in the province since 1990, 49 of which have been fracked.
Ms. Daigle said most of the waste water from New Brunswick gas wells is shipped to a treatment site in Debert, N.S., but she said if the industry were to expand, facilities might have to be built in New Brunswick.
She said the province is not considering the option of pumping the wastewater deep underground.
Hydraulic fracturing, or fracking, involves pumping water and chemicals into a gas well to fracture rock layers and release trapped pockets of shale gas. Critics say the process can poison groundwater, but proponents dispute that.
The study said that if the industry in New Brunswick were to expand as it has in Pennsylvania, there could be about 1,000 shale-gas wells drilled every year in the province.
"The amount of water required … would be equivalent to the annual water use for two to six cities the size of Fredericton," the report said.
But Ms. Daigle said the government has estimated that at full production, there could be up to 200 to 300 wells drilled annually. She said water use would be carefully monitored.
The professors have also recommended setting minimum depths for fracking, especially in places such as Albert County, where shale formations are closer to the surface and to groundwater supplies than they are in other areas of the province.
They also said close attention must be paid to the construction of the wells, with the use of trained well-site inspectors who are independent from the industry.
There has been a strong public backlash to fracking in New Brunswick in recent months, including protests at the provincial legislature.
Natural Resources Minister Bruce Northrup is expected to release new shale-gas regulations later this spring.