A Canadian company’s plan to store nuclear waste near Lake Huron is alarming environmental groups and some Michigan lawmakers, who fear the project could eventually harm the Great Lakes.

For years, Ontario Power Generation has pushed to construct a deep geologic repository — a massive underground storage facility to handle low- to intermediate-level nuclear wastes — on the grounds of its Bruce nuclear facility near Kincardine, Ont. The company wants to locate its storage facility 2,230 feet below the ground and three-quarters of a mile from the Lake Huron shore.

Despite occasional flare-ups of opposition from elected officials and conservation groups over the potential effects on the Great Lakes, the proposal has continued to move through the approval process in Canada.

The repository is renewing debate about what is an acceptable risk posed by storage of all kinds of nuclear waste — from low-level materials including clothing and equipment exposed to radiation to high-level items like spent fuel. Critics of the Canadian power company’s Kincardine project, currently designed for low-to-medium-levels wastes, may be a precursor to high-level wastes being stored there in the future.

On Friday, the public comment period on the company’s environmental impact statement ended. Power company officials said that if remaining regulatory hurdles are cleared without delay, construction on the nuclear waste repository could begin before the end of next year.

In a race to get Michigan’s concerns on the record, the state Senate on Wednesday passed a resolution calling on Canadian officials “to address our concerns regarding the underground nuclear waste repository” and noting that the repository site would be “120 miles upstream from the main drinking water intakes for Southeast Michigan.” A similar resolution could be introduced this week in the House.

“I don’t know how much awareness has been raised in Michigan on this, so that’s what we’re trying to do,” said state Sen. Hoon-Yung Hopgood, who introduced the resolution. “We’re asking for an extension of the public comment period. … Some people have serious concerns that the way (Ontario Power) is building this, with excess capacity, will make it likely to house the high-level wastes.”

On Friday, Ontario Power spokesman Neal Kelly said the company would not extend the comment period since it already was extended 10 months ago.

Power firm officials contend they are investigating other sites in Ontario for a separate facility designated for the most dangerous materials. But for several environmental groups, even burying low-level wastes is a frightening prospect.

“The most serious concern is the contamination of the Great Lakes — leaking,” said Cheryl Grace, who lives in a community just north of Kincardine.

In 2012, she and others formed Save Our Saugeen Shores Inc. The group’s members argue the power company should continue to store its wastes above ground at nuclear reactor sites, which is the industry’s standard practice. In the United States, even the highest-level materials are stored on site — either in dry cask holding or spent fuel pools. Low to medium-level wastes are often handled by shallow land burial in lined pits.

But company officials said their proposed Kincardine site would house only low- to intermediate-level wastes. And the low-permeability limestone and shale formations beneath the surface “will safely isolate and contain the … nuclear waste for many thousands of years and beyond.”

“It’s located in 450 million-year-old stable rock in a seismically quiet area,” Kelly said. “This will safely isolate and contain the waste.”

The repository is not a new idea. Up until 2011, the United States funded plans for a similar repository for high-level wastes at the Yucca Mountain site in Nevada, but political concerns put the project in limbo.

The Ontario repository would be located at the Bruce Nuclear Generating Station — among the largest nuclear facilities in the world. Many residents in the Kincardine area along the eastern shore of Lake Huron owe the roofs over their heads and the food on their tables to OPG.

Roughly a decade ago, as the company was investigating permanent storage options, municipal officials floated the original idea of hosting the repository. The Bruce plant was already housing its nuclear waste and those of two other plants in the province on-site.

A central location would reduce the amount of waste needing to be transported around the region to various disposal sites. Murray Clarke, Kincardine’s chief administrative officer, said studies covering everything from the project’s environmental impacts to economic factors have suggested this a good deal.

Residents and elected officials have approved the project year after year, Clarke said.

“If there were significant concerns about the potential impacts to the lakes or the geomorphology, these are the people who would be most concerned about it,” he said. “The public here remains solidly behind the project.”

Others view it with growing alarm. One is John Mann III, another former Michigan resident who now lives in Canada near Kincardine.

“If this was such a good thing, we wouldn’t be getting it here,” he said. “It would be cropping up in places like Chicago or New York or Los Angeles.”

U.S. officials and groups hoping to challenge the project are essentially left with two options, said Noah Hall, a Wayne State law professor who specializes in environmental and international issues. To settle a dispute, the United States and Canada could ask for the intervention of the International Joint Commission — an agency created more than 100 years ago by both nations to address boundary issues.

Opponents, whether in the United States or Canada, also could challenge the progress through Ontario’s court system — an avenue Hall said has proven successful in the past.