Oneok Partners LP said it plans to invest $440 million in Wyoming’s Powder River Basin to buy a natural gas liquids (NGL) processing facility and to upgrade related infrastructure.

About $305 million of the investment will purchase Sage Creek, a 50 MMcf/d gas processing facility and NGL infrastructure from an undisclosed seller. The plant is in western Converse and Campbell counties. The rest of the money is set aside to upgrade and build midstream gathering lines, well connections and related infrastructure.

“The Sage Creek plant gives Oneok Partners additional natural gas gathering and processing capacity in a region where producers are actively drilling that has significant long-term growth potential,” said partnership President Terry K. Spencer. The plant adds assets “in and around our operating footprint that can be integrated into our system and used as a platform for future growth opportunities.”

The Sage Creek transaction, to be financed through debt and available cash, is set to close before the end of September. Completion of the related infrastructure buildout is expected in the second half of 2014. The partnership is to receive long-term acreage dedications, along with fee-based and percent-of-proceeds agreements with current Sage Creek producers.

As natural gas volumes increase to the Sage Creek system, and as NGL volumes are transported to the adjacent Oneok Partners-owned and operated Bakken NGL Pipeline in the next several years, management expects annual earnings to increase to $60 million from $40 million between 2015 and 2018.

Earlier this year, Oneok ramped up the Bakken NGL Pipeline, Stateline II gas processing facility and an ethane header pipeline (see Shale Daily, April 12). The Bakken pipeline carries liquids from the Bakken and Three Forks formations in the Williston Basin to the partnership’s half-owned Overland Pass Pipeline running from southern Wyoming to Conway, KS.

Oneok Partners also operates nearly 1,000 miles of gas gathering pipelines in Wyoming’s Powder River and Wind River basins.

The partnership plans to invest $5.2-5.6 billion through 2015 to acquire and expand gas midstream infrastructure across the onshore, including Sage Creek and the new expansions. Management said it also has a $2-3 billion backlog of growth projects not yet announced that it is evaluating.