The sit-in by four chiefs and a representative of another chief in Clark's West Kelowna office began Wednesday afternoon and comes more than one month after aboriginals first blocked waste-carrying trucks from entering an area, west of Merritt.
The company contracted to spread the waste, BioCentral, said in a news release that biosolids are used around the world to rejuvenate soil, and spreading the waste on land has less of an environmental impact than incineration.
The company has all the required permits, licences and permissions, it said.
Chief Aaron Sam of the Lower Nicola Indian Band said in a telephone interview from Clark's office that leaders met Environment Mary Polak twice and asked her to disclose where the waste was being spread, but the government has only provided a partial list.
First Nations are worried about impacts on land, water, traditional foods and health, he said, noting the government is legally obligated to consult with aboriginals.
"We're planning to stay here as long as it takes until we get a moratorium on biosolids coming in to the Nicola Valley," he said. "Yeah, we're prepared to stay here in the office overnight."
Sam said the waste is coming from the Okanagan and Fraser valleys.
"After the moratorium is in place, what we would like to do is have discussions with the province on how we can resolve this issue in the Nicola Valley so we can all come to some kind of agreement where all the parties are happy," he said.
Premier Christy Clark told reporters in Victoria that the government is working on a solution and she has spoken with the protesters' MLA, but the situation is complex. She said several provincial agencies, as well as the Thompson-Nicola Regional District, are involved.
"There's a lot of hands in the pot here, so it's taking a little bit more time than I would have hoped to get it settled," she said.
BioCentral said it respects the right to protest and will not haul the waste to the site until a compromise or alternative can be reached.
"The company is concerned about the length of this protest and potential impact long term to their business," stated the release.
BioCentral said the band has not accepted invitations to meet and "understands the issue at hand is not with their operations, but the current provincial legislation."
The company also said it works with provincial and municipal governments to ensure the biosolids meet or exceed guidelines.
-- by Keven Drews in Vancouver and Dirk Meissner in Victoria