MPLX LP Announces Formation of Strategic Joint Venture with Antero Midstream Partners LP

• MarkWest Energy Partners, L.P., a wholly owned subsidiary of MPLX LP, and Antero Midstream Partners LP have formed a strategic joint venture to support Antero Resources Corporation in the Marcellus Shale.
• Antero Midstream Partners will release to the joint venture its dedication from Antero Resources Corporation of approximately 195,000 gross operated acres located in Tyler, Wetzel and Ritchie counties of West Virginia.
• The joint venture will support the ongoing development of incremental gas processing required by Antero Resources Corporation in the Marcellus Shale.
• The joint venture is investing in fractionation capacity at MarkWest's Hopedale Complex in Ohio and has an option to invest in future fractionation expansions that support Antero Resources Corporation's liquids production.

FINDLAY, Ohio, Feb. 6, 2017 - MPLX LP (NYSE: MPLX) today announced that its wholly owned subsidiary, MarkWest Energy Partners, L.P., and Antero Midstream Partners LP (NYSE: AM) have formed a strategic joint venture to support the development of Antero Resources Corporation's (NYSE: AR) extensive Marcellus Shale acreage in the prolific rich-gas corridor of West Virginia.

The joint venture is owned 50 percent by MarkWest and 50 percent by Antero Midstream and is supported by a long-term, fee-based agreement with Antero Resources. As part of this agreement, Antero Midstream has agreed to release to the joint venture its 195,000 gross acre processing dedication from Antero Resources, increasing the Marcellus Shale area dedication to MarkWest from approximately 167,000 gross operated acres to over 360,000 gross operated acres. The additional dedicated acreage includes Antero Resources' core Marcellus Shale position in Tyler, Wetzel, and Ritchie counties of West Virginia.

To support Antero Resources' significant production growth profile, the joint venture will expand processing infrastructure at its Sherwood Complex in Doddridge County, West Virginia. The Sherwood Complex began operations in October 2012 and has grown to become the single largest gas processing complex in the Northeast, currently with six cryogenic processing facilities totaling 1.2 billion cubic feet per day of capacity.

Ongoing development of gas processing infrastructure at the Sherwood Complex includes three new joint venture processing facilities, totaling 600 million cubic feet per day of incremental capacity for Antero Resources. The joint venture expects to commence operations of two of the new facilities during the first quarter and third quarter of 2017, and the third new facility during the first quarter of 2018. In addition to the three new processing facilities, the joint venture contemplates the development of up to another eight processing facilities to support Antero Resources, which would be located at both the Sherwood Complex and a new location in West Virginia.

MarkWest will continue to construct and operate all processing facilities installed to service Antero Resources' production and will also retain full ownership of the first six processing facilities at the Sherwood Complex.

In addition to the development of gas processing infrastructure, the joint venture will support the growth of Antero Resources' natural gas liquids (NGL) production with fractionation infrastructure at the Hopedale Complex in Harrison County, Ohio. The largest fractionation facility in the Marcellus and Utica shales, the Hopedale Complex currently has three units providing 180,000 barrels per day (bpd) of propane-plus fractionation capacity. The joint venture is investing in 20,000 bpd of existing fractionation capacity at the Hopedale Complex, and has an option to invest in future fractionation expansions at the complex subject to the production of incremental NGLs from the joint venture's processing facilities. MarkWest and its affiliates will continue to fully own and operate all NGL pipelines, rail and marketing infrastructure associated with the Hopedale Complex. In addition, MarkWest will continue to fully own and operate all fractionation facilities and related NGL infrastructure in the Marcellus Shale. 

MarkWest will initially contribute existing assets to the joint venture consisting of the three processing facilities currently under construction at the Sherwood Complex, as well as associated infrastructure related to the operation of these facilities. Antero Midstream will initially contribute approximately $155 million for its allocated share of processing assets at the Sherwood Complex and ownership of fractionation capacity at the Hopedale Complex. Going forward, it is expected that MarkWest and Antero Midstream will each contribute 50 percent of the future capital investments for the joint venture.

"MPLX is excited to continue expanding our midstream operations on behalf of Antero Resources by partnering with Antero Midstream," commented MPLX President Don Templin. "This unique transaction further strengthens our long-term relationship with the largest producer in the Appalachian Basin and provides MPLX with substantial future organic growth opportunities."  

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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 and storage of crude oil and refined petroleum products. Headquartered in Findlay, Ohio, MPLX's assets consist of a network of common carrier crude oil and products pipeline assets located in the Midwest and Gulf Coast regions of the United States; an inland marine business; a butane storage cavern located in West Virginia with approximately one million barrels of storage capacity; crude oil and product storage facilities (tank farms) with approximately 4.5 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, 54 gas processing plants, 14 NGL fractionation facilities and two condensate stabilization facilities.

Investor Relations Contacts:
Lisa D. Wilson (419) 421-2071
Doug Wendt (419) 421-2423
Denice Myers (419) 421-2965

Media Contacts:
Chuck Rice (419) 421-2521
Katie Merx (419) 672-5159

About Antero Midstream Partners LP
Antero Midstream Partners LP is a limited partnership that owns, operates and develops midstream gathering, compression and integrated water assets located in West Virginia and Ohio.  The Partnership's website is located at http://www.anteromidstream.com.

For more information, contact Michael Kennedy - CFO of Antero Midstream at (303) 357-6782 or [email protected].

Forward-looking statements

This press release contains forward-looking statements within the meaning of federal securities laws regarding MPLX LP ("MPLX"). These forward-looking statements relate to, among other things, expectations, estimates and projections concerning the business and operations of MPLX. You can identify forward-looking statements by words such as "anticipate," "believe," "design," "estimate," "expect," "forecast," "goal," "guidance," "imply," "intend," "objective," "opportunity," "outlook," "plan," "position," "pursue," "prospective," "predict," "project," "potential," "seek," "strategy," "target," "could," "may," "should," "would," "will" or other similar expressions that convey the uncertainty of future events or outcomes. Such forward-looking statements are not guarantees of future performance and are subject to risks, uncertainties and other factors, some of which are beyond MPLX's control and are difficult to predict. Factors that could cause MPLX's actual results to differ materially from those implied in the forward-looking statements include: our ability to achieve the strategic and other objectives related to the transactions described herein; the adequacy of MPLX's capital resources and liquidity, including, but not limited to, availability of sufficient cash flow to pay distributions, and the ability to successfully execute its business plans and growth strategy; the timing and extent of changes in commodity prices and demand for crude oil, refined products, feedstocks or other hydrocarbon-based products; continued/further volatility in and/or degradation of market and industry conditions; changes to the expected construction costs and timing of projects; completion of midstream infrastructure by competitors; disruptions due to equipment interruption or failure, including electrical shortages and power grid failures; compliance with federal and state environmental, economic, health and safety, energy and other policies and regulations and/or enforcement actions initiated thereunder; changes to MPLX's capital budget; other risk factors inherent to MPLX's industry; and the factors set forth under the heading "Risk Factors" in MPLX's Annual Report on Form 10-K for the year ended Dec. 31, 2015, and Quarterly Report on Form 10-Q for the quarter ended March 31, 2016, filed with the Securities and Exchange Commission ("SEC"). In addition, the forward-looking statements included herein could be affected by general domestic and international economic and political conditions. Unpredictable or unknown factors not discussed here, in MPLX's Form 10-K or Form 10-Q could also have material adverse effects on forward-looking statements. Copies of MPLX's Form 10-K and Form 10-Q are available on the SEC website, MPLX's website at http://ir.mplx.com or by contacting MPLX's Investor Relations office.