The federal government has punted a decision on whether to allow a proposed underground storage bunker to house nuclear waste near Lake Huron well into next summer.

In a notice Monday, cabinet issued an order allowing another 243 days for the government to decide on the politically fraught project.

There have been several such extensions since a review panel in May last year gave its approval to the deep geologic repository, which has drawn vehement opposition from local groups as well as hundreds of Canadian and American communities around the Great Lakes.

Ontario Power Generation proposes to construct and operate the underground facility for the long-term management of radioactive waste at the Bruce nuclear site near Kincardine, Ont. The proposal calls for hundreds of thousands of cubic metres of so-called low- and intermediate-level nuclear waste to be buried 680 metres underground in the bedrock.

The preliminary approval concluded that the $1-billion repository would be the best way to deal with the waste, and posed only a minor risk to the lake provided several conditions were met.

The government was to have made its decision in September 2015 but the former Conservative government extended the deadline until March 1 to allow for the federal election that brought the Liberal government of Justin Trudeau to office.

In February, Environment Minister Catherine McKenna asked the power utility to provide more details and do further environmental studies of the proposed repository. The information was due this month.

The Canadian Environmental Assessment Agency is now considering the data supplied by the utility, and will also be looking for public feedback on the new information before deciding under what conditions the project might be able to proceed.

The environmental assessment process has been going on since January 2006 and OPG had hoped it could begin construction in 2018 and have the facility operational by 2025.

Proponents argue the rock is geologically stable and would provide a hermetic seal to prevent any radioactivity reaching the lake about 1.2 kilometres away for tens of thousands of years.

Opponents, some of whom took their fight against the project to court, argue such a facility would be too risky given the proximity to Lake Huron. They worry any contamination could threaten drinking water used by millions of people. They have been urging McKenna to kill the project outright.

In October, the agency said it would make money available to help the public and indigenous groups take part in the assessment process. The deadline for funding applications was November 22 and those are now under review, the agency said.