Bill Fraser says he has been hearing concerns from residents for months about sections of line in poor shape with cracked ties and missing bolts.
He says the concerns have been heightened as a result of two CN (TSX:CNR) freight train derailments in the province in the last three weeks.
Fraser said he walked along a kilometre of rail line in Miramichi to see the state of the rail line for himself.
"There were many areas along that spur line where there was blue paint sprayed as an indication that CN had identified a problem that had to be fixed," he said. "The problem is, it didn't look to me that anything was fixed."
"I'm not going to be comfortable until an independent assessment is done by Transport Canada."
But CN spokesman Jim Feeny says the rail line is maintained at a high standard and nearly $28 million has been spent on track infrastructure between Moncton and the Quebec border over the last three years.
"CN's policy is to meet and generally exceed all Transport Canada regulatory standards," Feeny said Tuesday in an interview from his office in Montreal.
He said the rail line is normally inspected and maintained by CN.
Calls to Transport Canada for comment were not immediately returned.
Feeny said it was highly unusual to have two derailments in a small area in such a short period of time.
He said the cleanup of a five-car derailment in Edmundston on Sunday night continued Tuesday as crews removed the last of the liquefied petroleum gas and clay slurry from overturned tankers.
There was no leak nor fire and nobody was injured.
Feeny said investigators do not have a preliminary cause of the derailment.
"We're examining it very closely because of the highly unusual circumstances and we will continue that investigation until we've determined exactly what has happened here," Feeny said.
A cracked wheel is believed to be behind the fiery derailment on Jan. 7 of 19 cars and a locomotive near Plaster Rock.