VANCOUVER - While Prime Minister Stephen Harper says the fate of Enbridge's proposed pipeline from the Alberta oilsands to tankers on the British Columbia coast will be based on science and not politics, documents show some of that science isn't forthcoming.

And critics say there is no time for the science to be completed before a federal deadline for the environmental assessment currently underway.

Documents filed with the National Energy Board show the environmental review panel studying the Northern Gateway project asked Fisheries and Oceans Canada for risk assessments for the bodies of water the proposed pipeline will cross. The pipeline is to traverse nearly 1,000 streams and rivers in the upper Fraser, Skeena and Kitimat watersheds.

The department didn't have them.

"As DFO has not conducted a complete review of all proposed crossings, we are unable to submit a comprehensive list as requested; however, this work will continue and, should the project be approved, our review will continue into the regulatory permitting phase," DFO wrote in a five-page letter dated June 6, 2012.

The response went on to say there "may be differences of opinion" between the company and the department on the risk posed by the pipeline at some crossings. It provided two examples of crossings of tributaries to the Kitimat River where Enbridge rated the risk as low but Fisheries rated it medium to high.

DFO said the federal ministry will continue to work with the company to determine the risk level and level of mitigation required.

"DFO is of the view that the risk posed by the project to fish and fish habitat can be managed through appropriate mitigation and compensation measures," said the department's response.

"Under the current regulatory regime, DFO will ensure that prior to any regulatory approvals, the appropriate mitigation measures to protect fish and fish habitat will be based on the final risk assessment rating that will be determined by DFO."

Earlier this month, Harper told reporters in Vancouver that "decisions on these kinds of projects are made through an independent evaluation conducted by scientists into the economic costs and risks that are associated with the project, and that's how we conduct our business."

He went on to say "the only way that government can handle controversial projects of this manner is to ensure that things are evaluated on an independent basis, scientifically, and not simply on political criteria.''

But the federal government recently sent letters to 92 habitat staff members within Fisheries and Oceans in B.C., telling them that their positions will be cut. Thirty-two of them will be laid off outright.

The cuts will mean the department in B.C. has half the habitat staff it had a decade ago.

All but five of the province's fisheries field offices will be cut as part of a $79 million — 5.8 per cent — cut to the department's operational budget, including the offices in Prince George and Smithers that would have had the lead in monitoring pipeline effects.

The marine contaminant group that would have been involved in a spill in B.C. has been disbanded and the fisheries and environmental legislation gutted, said Otto Langer, a retired fisheries department scientist.