Salt domes

It’s relatively common along the U.S. Gulf Coast to use underground salt domes to store crude oil, natural gas, mixed NGLs and so-called NGL “purity products” like ethane and propane. There are also a handful of salt cavern storage facilities in Kansas, Michigan, New York and Virginia. But in the Rockies and the West Coast states they’re rare as hen’s teeth, one of the few examples being Sawtooth Caverns, a one-of-a-kind facility in Utah that not only stores propane and butanes but also gasoline and diesel. In today’s RBN blog, we discuss Sawtooth Caverns and its increasing role in the sprawling region’s NGL and refined products markets. 

Every day, the “wet” Marcellus and Utica shale plays are producing significant volumes of ethane, all of which needs to be moved out of regional plants, fractionators and de-ethanizers immediately, either by “rejection” into natural gas or on pipelines to the Gulf Coast, Ontario, or to an export terminal in Marcus Hook, PA. A leading midstream company—MPLX’s MarkWest subsidiary—has developed an ingenious, integrated approach for handling much of that ethane (and dealing with any disruptions), but its ethane-management system is not a regional cure-all, and the likely development of an ethylene plant in the heart of the Marcellus/Utica would only increase the region’s ethane-handling needs. Today, we continue our examination of natural gas liquids (NGL) storage needs in the Northeast with a look at how nearby ethane storage might help midstream companies that are not integral parts of MarkWest’s “ethane loop.”