Trace amounts of methane have been detected in dozens of wells in parts of the province untouched by oil or gas exploration, say researchers at the University of New Brunswick.
"This is what we expected," said Diana Loomer, of the department of civil engineering, and manager of the baseline groundwater quality project, which was done in conjunction with the New Brunswick Energy Institute.
The study was conducted in Kent County and Sussex, two areas of possible shale gas development. A total of 254 private wells were tested in the past year.
"In the Richibucto area, there is not even an old historic well that had been decommissioned, so it represents complete baseline," said Loomer.
"In the Sussex area, there has been, and there does exist, some producing oil wells and some natural gas wells," she said, but most testing was conducted at least 1.6 km away from those sites.
Loomer says only one well had to be reported to public health for having dangerously high concentrations of methane, but 90 per cent of those wells that did test positive had concentrations of less than 1 mg/L.
At that low level, Loomer says homeowners would not be able to smell or taste the gas and the methane would be non-toxic.
"Anything below 10 milligrams per litre is considered fine and a well owner wouldn't have to do anything," said Loomer.
Flammability only starts to becomes an issue at levels of 28 mg/L, she said.
Phase 2 set to start in June
The baseline groundwater project was launched under the former Alward government, which campaigned on the promise of developing the shale gas industry.
By gathering baseline data, scientists would be able to measure any future contamination caused by hydraulic fracturing, also known as hydro-fracking.
It's a process of extracting natural gas from shale rock formations beneath the earth's surface. It involves injecting a mixture of sand, chemicals, and water or some other substance into the earth under high pressure to fracture the rock and capture natural gas that is otherwise not attainable.
Opponents fear the process could endanger the groundwater supply and potentially have other harmful environmental effects.
While the Gallant government has imposed a moratorium on fracking, the second phase of the baseline groundwater quality study is moving ahead.
Next week, researchers will send mailouts to property owners in the St. Antoine-Shediac region and the Boiestown-Upper Blackville Region, with testing expected to start there in June.
Phase one of the project tested 152 wells in the Sussex area and 102 in Kent County.
In the Kent area, 69 per cent of the wells contained detectable dissolved methane In the Sussex area, it was 50 per cent.
Loomer says the laboratory also detected iron, manganese and arsenic.
She says iron and manganese are more problematic from an aesthetic point of view, because they cause staining.
Loomer says most well owners with elevated levels of arsenic were already aware that it was present and would have known that treatment was required.
The research team is working on developing a digital map, which will show regional results without revealing the identity of individual properties.
Loomer says it's important to have an independent database that's been gathered and published by academics.