The Sipekne'katik First Nation and a number of other groups will file an appeal with the Nova Scotia environment minister on Thursday after the province last month approved an application by AltaGas Ltd. to proceed with its Alton natural gas storage project near Stewiacke.

AltaGas wants to store natural gas in three underground salt caverns near Stewiacke, N.S.

Environmental concerns focused on the release of salty water from drilling the underground caverns into the Shubenacadie River system.

Mi'kmaq chiefs had complained they had not been adequately consulted.

Chief Rufus Copage

Chief Rufus Copage says the band has fixed gaps in its record keeping and put in place stricter financial controls. (CBC)

Sipekne'katik Chief Rufus Copage said his band was working with some experts to try and understand what the project would mean for his community. He said they planned to set up community meetings and hold a referendum on the issue.

But on Jan. 20, the province gave AltaGas Ltd. the green light to proceed. Nova Scotia's Liberal government said that after 18 months it had satisfied its obligation to consult with the First Nations and modifications to the project were made.

"We're still looking at maybe holding a referendum anyway, we're still going to have community meetings," Copage said.

Copage said he felt left out of the process to the very end.

"The night they were making phone calls around, the minister was calling all the chiefs to let them know they were going to do approvals for the gas, but for some reason, I seem to be the only chief that wasn't notified. I am closest to the river," he said.

On Wednesday evening, Copage said lawyers were putting together the final documents and they would be presented to the province on Thursday morning.

He said at 11:00 a.m. representatives from Sipekne'katik First Nation and several area environmental groups would meet at the Mi'kmaq Native Friendship Centre in Halifax.

"As of right now, as of right this minute, my understanding is the province already approved Alton gas, but hopefully the appeal will stop it, yes."