With major concessions from Canada on dairy, some Ontario critics say they're concerned about what NAFTA's proposed replacement means for the industry.

The provisional deal known as the United States-Mexico-Canada Agreement (USMCA) has plunged some dairy farmers into uncertainty, with some now concerned that they might not be able to survive.

The new deal would give U.S. farmers greater access to Canada's dairy industry, worth about 3.6 per cent of Canada's current dairy market, according to the Dairy Farmers of Canada.

Dairy farmer Vicki Cork has heard from Dairy Farmers of Ontario that the number could even be as high as 3.9 per cent and says the higher figure gets her worried.

"The bigger the number, the worse it's going to be, so we're just sort of [bracing] for the worst," she told CBC News Saturday at the Norfolk County Fair in Simcoe, Ont. — one of the largest agricultural fairs in the province.

"We're a sixth-generation dairy farm, and we're probably not going to survive this, so I guess it just sucks to be us."

Dairy farmer Vicki Cork speaks to CBC about the impact of the USMCA trade deal. 1:36

Foreign Affairs Minister Chrystia Freeland said Monday that farmers will receive compensation from the federal government, but details weren't immediately available.

Cork claims that she hasn't received any communication on what compensation may look like outside of a "pretty vague" email she got from the Dairy Farmers of Ontario.

"I look after the books for the farm, so I'm terrified," she said. "Until they actually say something official, we really have no idea what the compensation will look like."

Ontario's Minister of Agriculture Ernie Hardeman told CBC News that consultations will be made with the province's agriculture community to determine the cost associated with the new deal. He said he plans to ensure the federal government foots the bill.

Ontario's Minister of Agriculture Ernie Hardeman says consultations are underway to see how some Crown forests in northern Ontario could be sold and converted to farmland. (Keith Burgess/CBC)

"It is quite obvious that opening up the market to the American market is going to hurt our producers," he said at the Norfolk County Fair. "They made the deal, they should pay for the penalty that is caused by the deal."

Some critics say the deal also erodes the supply management system, which puts quotas on the amount of milk farmers are allowed to produce. The quotas prevent overproduction that would otherwise hurt prices and farm incomes.

The system also put high tariffs on foreign producers trying to sell in the Canadian market, limiting foreign products on Canadian shelves.

Cork says Canada's supply management system has been successful and the envy of countries around the world.

"The quota system was put in place because the government told us to manage our own system and we did and we were successful. We were too successful," she added. "Other countries wanted into that. They wanted access to it, and our government sold us out."

Cork says she has no animosity toward other dairy farmers or American dairy farmers, but rather the government.

The new USMCA deal would give U.S. farmers greater access to Canada's dairy industry. (CBC)

"[Americans] envy our supply management and they want the government to help them implement supply management in the United States," she said. "So why not help them do that instead of taking away from us because we had something successful?"

The deal would also eliminate Class 7, which essentially created a discounted price on Canadian-produced milk ingredients, so they could compete with similar products exported into Canada from the United States. The pricing system was introduced in March last year, which made the American equivalents uncompetitive.

Now with the new trade deal in motion, Cork is asking that Canadians specifically look for products that are made in Canada to help farmers at home.

"I would really hope that the general public would just really support your Canadian farmers," she said. "You might pay a few cents more, but it was grown here. It was grown ethically and safely, and you're supporting your neighbour."