OTTAWA (Reuters) – Environmental groups launched  a complaint against Canada under the North American Free Trade  Agreement on Wednesday, saying the country has failed to  enforce anti-pollution rules governing its vast oil sands.

In the latest move in a long-running campaign to highlight  the impact of oil sands development, the submission by  Environmental Defence Canada, Natural Resources Defense Council  and three citizens charges that toxic tailings ponds are being  allowed to leak and contaminate ground water.

The ponds store residual oil, heavy metals and other  byproducts of oil sands processing in the western province of  Alberta. They are subject to environmental provisions under the  federal Fisheries Act, the groups said.

“We’re out of options when it comes to trying to get the  government to enforce its law,” Matt Price, policy director at  Environmental Defence Canada, told reporters.

“This is one avenue where we can, at the very least,  embarrass the Canadian government into trying to enforce its  law by having Mexican and US officials essentially poring  over our dirty laundry, which is not something Canada wants,”  he said.

Tailings ponds came to symbolize the battle between green  groups and the oil sands industry in 2008, when 1,600 ducks  were killed when they landed on a tailings pond at Syncrude  Canada Ltd’s operation. Syncrude faces federal and provincial  charges over the incident and the case is now being tried.

Meanwhile, people in a small settlement on Lake Athabasca,  downstream from the massive energy projects in northern  Alberta, suffer unusually high rates of cancers, but provincial  health officials have been reluctant to tie that to water  contamination from the oil sands.

One of the three citizens behind the submission lives in  that community, Fort Chipewyan, Alberta.

Environment Minister Jim Prentice said there is no data to  support the allegation that there is leeching from tailing  ponds into the Athabasca River, but promised to study the  situation more closely.

“I’ve indicated to the department that this is a serious  issue of real concern and that I expect them to step up the  monitoring efforts,” he told reporters in Ottawa.

Oil sands developers have countered the green groups with  their own communications push, one they expanded last week.  They say their environmental standards are high and they are  making strides in improving performance.