Fifty-four years after mercury was first dumped into the river system near Grassy Narrows in northern Ontario, poisoning the fish and any person or creature that ate them, Environment Minister Glen Murray is finally promising to clean up the water.

It’s about time.

Study after study has shown that generations of people from the Grassy Narrows and Whitedog First Nations have been poisoned as the provincial government mishandled the file and obfuscated the truth.

Indeed, it is only in the face of dogged reporting this year by the Star’s Jayme Poisson and David Bruser that the government’s hand was finally forced. It had to admit that the river system was not cleaning itself up, something it had been arguing as late as this May despite piles of studies that indicated the opposite.

The latest evidence that the mercury is not dissipating or that it continues to seep in from unknown sources comes from a comprehensive analysis of provincial fish data conducted for the Star.

It shows the walleye that people in Grassy Narrows are eating are the most mercury-contaminated in the province. In fact, the mercury in an average meal of walleye from Clay Lake is 15 times the daily tolerable intake limit for adults, and about 40 times the limit for women of child-bearing age, pregnant women and children.

That comes on top of several other studies released this year — all of which the government would have known about — that show mercury continues to poison the waterways the two reserves depend on.

In turn, the 1,500 people on those reserves continue to get sick.

One disturbing Japanese study, for example, found that 90 per cent of residents from the two reserves tested in 2014 had a symptom of mercury poisoning. Those can include loss of muscle co-ordination, slurred speech and tunnel vision. Another study found the level of mercury in babies tested from both reserves between 1978 and 1992 was high enough to affect brain development.

While Murray’s promise is welcome, it must come with a guarantee that the government will be transparent as it moves forward on the cleanup.

It hasn’t been in the past. Indeed, when a retired mill worker told the government that he was part of a crew that “haphazardly” dumped drums of mercury and salt into a pit behind the Dryden mill more than 40 years ago the government dismissed his concerns that the containers might be leaking.

Only after the Star asked questions did the province send out investigators to look for the dump site. On Wednesday, Murray said the barrels are not there.

But his ministry has ignored repeated questions from the Star about how the search was proceeding. So who’s to know whether they are there or not if the government will not share information about how it conducted the search?

It’s also disturbing that the province kept data showing how contaminated the fish were secret. It took Poisson and Bruser two months and multiple requests to obtain it from the province.

There are two final points to be made in this disturbing story.

First, the government must stop its wrong-headed fight with the Grassy Narrows reserve in court to permit clear-cut logging in the area. If allowed, studies indicate it would release more mercury into the river system.

Second, the province must bump up its original meager compensation package to the people of the Grassy Narrows and Whitedog reserves.

It can’t make up for the illnesses and loss of a way of life for generations of people in the north. But it can do everything possible now to mitigate the damage.