Public hearings on the environmental repercussions of the proposed Energy East pipeline project heard contradictory assessments this week when it comes to the effect of a major spill on waterways in Quebec.

Earlier this week, TransCanada presented a worst-case scenario simulation involving a total rupture of the pipeline near the Etchemin River in the Chaudière-Appalaches region of eastern Quebec.

The company said it would take just over five hours for an estimated 3.6 million litres of oil to reach the river and threaten water intakes for the municipalities of Lévis and Quebec City.

In the case of lateral rupture, it would take a spill two-and-a-half hours to reach the river.

The $15.7-billion Energy East pipeline would carry a million barrels a day of western crude as far east as Saint John to serve domestic refineries and international customers. 

The scenario led Joseph Zayed, who is presiding over the hearings, to question why TransCanada does not include watersheds that feed municipal water supplies and wells serving 15 people or less among its identified sensitive areas, known as Highly Sensitive Receptors (HSR).

According to TransCanada, HSRs include "cities, towns, areas where species at risk are present, water wells and other surface water intakes around the proposed pipeline route" and shut-off valves are prioritized in those areas.

"How can you justify this exclusion," Zayed asked, saying the lack of details left him "troubled."

Assessments questioned

The hearings also heard a presentation by Savaria Experts Environnement, a firm hired by the Montreal Metropolitan Community to assess the risks of an oil spill.

Chantal Savaria questioned TransCanada's claim that it could respond to a spill in 13 minutes.

Even in that best-case scenario, between two and 10-million litres of oil could be released into the environment, Savaria said.

A 60-minute spill response, which was how long it took Enbridge to respond to a spill in Terrebonne in 2011, could see more than 16-million litres spill depending on the interval between shut-off valves, she said.

Savaria also questioned the findings of a TransCanada-commissioned report by the pipeline builder Stantec, which found that it would take more than nine hours for an oil spill to reach a water intake on the Ottawa River.

Savaria argued that it would only take four hours.

TransCanada assured the hearings that it was responsible for ensuring that any community affected by an oil spill had an adequate supply of drinking water and that it was working with communities to build contingency plans.

Translated from a report by Radio-Canada's Laurence Niosi and Christine Bureau