Utica Build-Out Projects Begin Operations, Provide Connectivity to Midwest Refineries

FINDLAY, Ohio, July 6, 2017 - MPLX LP (NYSE: MPLX) President Michael J. Hennigan today announced that MPLX's Utica Build-Out projects, including the newly constructed Harpster to Lima Pipeline, are now fully operational.

"The Utica Build-Out projects are part of MPLX's commitment to provide cost-effective industry solutions through expansion of existing pipelines and construction of new pipelines to meet the needs of Utica and Marcellus shale producers," said Hennigan. "The Cornerstone Pipeline and the Utica Build-Out pipelines are key liquids pipelines from these shale plays and they now provide connectivity to refineries throughout the Midwest."

The new 49-mile Harpster to Lima Pipeline is designed to transport condensate and natural gasoline in a batched system from Harpster, Ohio, to a tank farm in Lima, Ohio, where it can then continue on to refineries in Ohio, Michigan, Indiana, and Illinois. As part of the Utica Build-Out scope, MPLX has also expanded capacity of two product pipelines, including the East Sparta to Heath and Heath to Harpster pipelines to deliver into the new pipeline at Harpster. In December 2016, MPLX reversed the RIO 8-inch pipeline to provide further distribution to the Midwest from Lima. MPLX is currently constructing additional connectivity and expanding pipelines to provide diluent service to western Canada, which is expected to be complete in 2017.

"The Utica Build-Out projects are the next step of our Utica shale strategy," Hennigan added. "MPLX now offers connectivity to the Midwest, and these projects support our plans to also serve the diluent market in Canada."

The East Sparta to Heath Pipeline is an 81 mile, 8-inch pipeline. The Heath to Harpster Pipeline is a 67 mile, 10-inch pipeline. The Harpster to Lima Pipeline is a 49-mile, 12-inch pipeline. All three pipelines now have a capacity of 50,000 barrels per day. Marathon Pipe Line LLC, a subsidiary of MPLX, will operate these pipelines from its operations center in Findlay, Ohio, and with local operational personnel.

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About MPLX LP
MPLX is a diversified, growth-oriented master limited partnership formed in 2012 by Marathon Petroleum Corporation to own, operate, develop and acquire midstream energy infrastructure assets. We are engaged in the gathering, processing and transportation of natural gas; the gathering, transportation, fractionation, storage and marketing of NGLs; and the transportation, storage and distribution of crude oil and refined petroleum products. Headquartered in Findlay, Ohio, MPLX's assets consist of a network of crude oil and products pipeline assets located in the Midwest and Gulf Coast regions of the United States; 62 light-product terminals with approximately 24 million barrels of storage capacity; an inland marine business; storage caverns with approximately 2.8 million barrels of storage capacity; crude oil and product storage facilities (tank farms) with approximately 5 million barrels of available storage capacity; a barge dock facility with approximately 78,000 barrels per day of crude oil and product throughput capacity; and gathering and processing assets that include more than 5,600 miles of gas gathering and NGL pipelines, 55 gas processing plants, 14 NGL fractionation facilities and two condensate stabilization facilities.

Investor Relations Contacts:
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Doug Wendt (419) 421-2423

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Forward-looking Statements

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