United Conservative Party Leader Jason Kenney speaks at an Edmonton Chamber of Commerce lunch on Nov. 14, 2018. (CODIE MCLACHLAN / STARMETRO EDMONTON)

Newly-sworn-in Alberta Premier Jason Kenney will be a final witness Thursday in the last of a marathon series of Senate committee hearings on sweeping environmental and resource development legislation.

Kenney has already vowed to challenge the legislation in court.

Kenney’s appearance was finalized late Tuesday as the Senate Committee on Energy, the Environment and Natural Resources hammered out final details before it begins clause-by-clause voting on the 357-page bill next week.

Although the committee has sought an extension, it is committed to report the legislation, Bill C-69, back to the Senate next Thursday after hearing from more than 200 witnesses in a chain of 30 hearings, including meetings across Canada, since last February.

It appears inevitable the committee will propose not just a few, but many amendments to the legislation.

The chair of the committee, independent senator Rosa Galvez, told the committee Wednesday night that up to 50 suggested amendments have been received from industry, non-governmental advocacy organizations and municipalities.

Other senators on the committee engaged with Indigenous witnesses, who expressed support for most aspects of the legislation surrounding consultation and involvement in energy and resources projects with consent by First Nations.

Sections of the bill reflect commitments in the United Nations Declaration on Rights of Indigenous Peoples, even though Parliament has not yet passed an NDP private members bill that would require Canadian federal law to be guided by the UN accord.

Bill C-69, which would dismantle the 2012 Environmental Assessment Act passed by the former Conservative government of Stephen Harper, would also create two new acts governing resource development and environmental protection — the Impact Assessment Act and the Canadian Energy Regulator Act — while also amending the Navigation Protection Act and other laws to establish a new regime for environmental protection in major energy projects.

The House of Commons also held hearings into the legislation — one of the most contentious the Trudeau government has introduced over its four-and-a-half years in power — but not to the extent of the Senate review.

The Commons Standing Committee on Environment and Sustainable Development held only 14 witness hearings before sending the bill back to the Commons last June after Environment Minister Catherine McKenna tabled it in February, 2018.

Kenney`s slot as a witness was finalized after he was sworn in as Alberta’s premier on Tuesday.

His appearance will be followed only by wrap-up testimony from McKenna, Transport Minister Marc Garneau and Natural Resources Minister Amarjeet Sohi, an Edmonton MP.

Kenney made the vow to challenge Bill C-69 his first promise soon after the Alberta election campaign began last March.

“I will direct our attorney general immediately to file a constitutional challenge to strike it down,” Kenney said on the third day of campaigning.

A string of energy sector witnesses and economists have testified against Bill C-69 on grounds it will further delay resource development following court action or federal government decisions that have either delayed or, in the case of the Northern Gateway pipeline from Albert to the B.C. coast, led to the cancellation of pipeline projects.

The projects were central to Alberta’s hopes of developing new oil and gas markets abroad, rather than depending on U.S. markets.

“I believe Bill C-69 potentially leaves New Brunswick and Atlantic Canada out of the economic opportunities already enjoyed by the rest of Canada, not because of economics, but because of rules, I find this unacceptable,” the newly-elected Conservative premier of New Brunswick, Blaine Higgs, told the committee Wednesday.

Higgs zeroed in on Justin Trudeau’s decision, even before the 2015 federal general election, to oppose the Energy East project.

The project would have involved a new pipeline, with a route through Quebec, to get oil from western Canada to mammoth existing refineries in New Brunswick.

Quebec residents and the Quebec government opposed the project.

Indigenous leaders have testified support for Bill C-69, welcoming new and stronger requirements for early contact and consent from First Nations and Indigenous Peoples.