Investor Presentaiton

IN AltaGas' Position in Marcellus Pipelines Connecting low cost producers with U.S. consumption markets and exports MI TN KY OH WV Marcellus / Utica Basins Central Penn ■■ Constitution Mountain Valley - Stonewall AltaGas PA MD VT NH NY DE NJ Cove point VA GAIL NC MA CT RI ME Stonewall US$135 Million Ownership: DTE (55%), ALA (30%), Antero (15%) Currently in service Designed to gather 1.4 Bcf/d from West Virginia Central Penn US$434 million Ownership: Williams (61%), ALA (21%), Ares/EIF (10%), Cabot (8%) Mountain Valley US$350 Million Ownership: EQT (45.5%), NextEra (31%), ConEd (12.5%), ALA (10%), RGC (1%) ☐ Designed to transport 1.7 Bcf/d as part of the "Atlantic Sunrise" project In service expected Q3 2018 Target in service Q1 2019 Designed to transport 2.0 Bcf/d from West Virginia to Virginia Constitution US$95 Million Ownership: Williams (41%), Cabot (25%), Duke/Piedmont (24%), ALA (10%) Designed to transport 0.65 Bcf/d to major northeastern markets GAIL Supply at Cove Point Natural gas sale and purchase agreement for a period of 20 years. ~2.5 mtpa of LNG (~0.35 Bcf/d) ■ Cove Point shipped first export cargo in March 20181 1 Source: Desjardins Capital Markets, National Gas Report, March 8, 2018 See "forward-looking information" 10

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