"We're asking for (federal Environment Minister Leona Aglukkaq) to hit the pause button on this," said Stephen Woodley, who was a Parks Canada chief ecosystem scientist.
He is one of 11 former Parks Canada supervisors who have signed a letter expressing concerns about plans for the Lake Louise ski area in Banff National Park.
The signatories include one-time park superintendents and planners as well as three retired national directors.
Earlier this month, Parks Canada released guidelines for development at Lake Louise, one of Canada's largest ski resorts and a regular World Cup race venue. The document was crafted in consultation with ski-hill management and is intended to stand for the next 42 years.
The guidelines would allow several warming huts to be built along with a large facility on the top of Mount Whitehorn. About 1,000 hectares from the resort's leasehold would be exchanged for permission to put runs on 500 currently unused hectares.
Woodley said that swap simply means the resort would be letting go of land that isn't developable anyway for wilderness that is.
"It takes away areas that are now designated wilderness and turns them into ski runs. These are legislated, designated wilderness areas within Banff and it opens them up for development."
The overall effect, including new lifts and facilities, would increase the resort's footprint by 30 per cent, Woodley said.
Parks Canada officials have said that any actual construction would be preceded by an environmental assessment and public review. But Woodley said environmental protection in Banff, a UNESCO World Heritage Site, should come first.
"You can't run a national park and a world heritage site by saying, 'We'll fit in whatever fits under an environmental assessment.'
"There's a higher standard here."
The letter also says much of the science used to develop the guidelines is outdated.
It also points out that bears are attracted to plants that grow on ski runs in the summer, so adding more runs could increase bear encounters in the park.
The guidelines were developed by resort management and Parks Canada with no public input, Woodley said. The comment period ends Sunday.
"It comes out of a closed process with a three-week public response period. (It's) a bit astonishing, really."
Parks Canada spokeswoman Melanie Kwong said the agency welcomes the letter.
"We will look at all the comments we received," she said. "If there are specific components that need to be addressed, we will do that."
She said Parks Canada is not considering changing its timeline for comment on the guidelines.
Woodley acknowledged that the guidelines contain some good ideas and that he and his colleagues don't oppose all resort expansion. But they all agree the current proposals need a re-think.
"There's some major potential impacts here."
— By Bob Weber in Edmonton. Follow him on Twitter at @row1960.
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