EQT Corporation, one of the top U.S. natural gas producers, announced Monday that it has entered into a joint venture with alternative asset manager Blackstone to sell minority stakes in several of its pipeline assets for $3.5 billion in cash.

The deal, which values the joint venture at approximately $8.8 billion, includes EQT’s ownership interests in its regulated transmission and storage assets, the Mountain Valley Pipeline, and the Hammerhead pipeline.

EQT has been working to reduce its debt load following the $14 billion acquisition of Equitrans Midstream in July. The company expects the pipeline sale, along with other recent asset sales in Pennsylvania, to help it exit 2024 with approximately $9 billion of net debt.

The Mountain Valley Pipeline, a 300-mile natural gas line running from West Virginia to Virginia, began operations in June after years of legal challenges, with EQT’s stake in the pipeline entity considered one of the most valuable assets in the portfolio being sold.

The Hammerhead pipeline, with a capacity of 1.6 billion cubic feet per day, transports natural gas from production sites in Pennsylvania.

Following the announcement, its shares rose 3.9% in premarket trading on Monday, boosting the company’s valuation.