Protesters broke into the Muskrat Falls hydroelectric site in Labrador and formed a blockade around it, Nalcor Energy confirmed Saturday.
Nalcor spokeswoman Karen O'Neill said protesters and vehicles entered the work site near Happy Valley-Goose Bay Saturday afternoon, and a blockade of around 150 people formed outside the main entrance.
Mayor of Cartwright Dwight Lethbridge said demonstrators gained access to the site by cutting a chain off one of the gates. Lethbridge said he drove a "truckload" of people onto the site, but some protesters asked to be taken back as the situation grew "tense."
"There was the threat of RCMP coming to arrest people and there was a helicopter flying very low over our heads," he said. "It was a heart-pounding kind of moment."
Lethbridge described the demonstration as "extremely peaceful." Police were concerned that "things might escalate" between protesters and workers on the site, he said in an interview, but that has not been the case.
Protesters blocked access to the site over the last week, despite a court injunction that led to nine arrests Monday. The actions were in response to Nalcor's confirmation methylmercury levels are expected to rise in the reservoir created by construction of the project.
The provincial government has ordered Nalcor to remove forest cover from the land that will be flooded to create the 41-square-kilometre reservoir. Critics of the project say the water will be contaminated with toxic levels of methylmercury if too many trees are left to rot at the bottom of the reservoir, raising health concerns.
Nalcor says flooding is scheduled to begin later this month, though the company tweeted Saturday it won't happen this weekend.
A statement from Premier Dwight Ball said Nalcor would do nothing to increase water levels until a meeting with community leaders in the area that is set for Tuesday.
"We urge protesters to remain peaceful and be respectful in their actions for the safety of both themselves and workers onsite," Ball said in the statement issued Saturday.
O'Neill said earlier Saturday that Nalcor is working to secure the site and protect the safety of "people, facilities and equipment."
The RCMP said the main highway to Muskrat Falls was closed. Police confirmed the closure was linked to the protests and cited public safety concerns.
Lethbridge says the protesters include environmentalists, members of three aboriginal groups and nearby residents and they all have a long and varied list of demands.
"There are people here who want the project shut down no matter what," Lethbridge said. "Personally, I think the government is a bit too far in for that ... (The project) is officially a boondoggle, but they have the opportunity to make it righter than it has been."