This part of the Marine East 1 project includes a 70,000-b/d pipeline delivering NGL from the Marcellus region to Marcus Hook. The cyrogenic ethane tank will have a 300,000-bbl capacity, and the propane tank will have 500,000 bbl.

The company spokesman said that Sunoco Logistics has not updated the latest commissioning date for those new tanks.

“The new ethane and propane tanks are part of the Mariner East 1 project and both are in the final stages of construction now,” he said.

However, industry sources told OPIS earlier this week that the new storage tanks will be ready at year-end.

This will allow Marcus Hook terminal to export ethane for the first time and increase flow rate on Mariner East 1, possibly close to maximum. Also, Marcus Hook terminal will be ready to load Very Large Gas Carrier at the end of this year, in conjunction with the ethane delivery on that pipeline.

While Marcus Hook terminal will increase NGL export volume slightly, mostly from additional volume of ethane, later this year, a significant increase in export capacity will come at the end of next year when the Mariner East 2 pipeline comes onstream, sources said.

The Mariner East 2 is to ship an initial volume of 275,000 b/d of propane, butane and ethane from processing and fractionation complexes in western Pennsylvania, West Virginia and eastern Ohio for transport to the Marcus Hook Industrial Complex, but this west-east pipeline capacity could be increased drastically.

Sunoco Logistics is building four new additional storage tanks for ethane, propane and butane at Marcus Hook to accommodate the extra NGL delivery volume on Mariner East 2, the company spokesman said.

However, the company has not publicized the storage capacity for the four new tanks yet, he said.

Currently, Marcus Hook terminal has a total of 2 million bbl of propane and butane storage capacity in underground caverns. There is no product breakdown for the underground storage.

The East Coast exported about 1.766 million bbl of propane in September, the highest monthly volume ever, according to the Energy Information Administration.

The East Coast’s propane exports have exceeded the 1-million-bbl mark for five consecutive months since May. Prior to May, monthly propane exports have surpassed the 1-million-bbl mark only once in October 2014.

Besides propane exports, Mariner East 1 is also serving domestic propane customers in the winter months.

Meanwhile, Sunoco Logistics has yet to comment on the outcome of the open season for its Mariner East 2 expansion plan.

Looking east toward Europe, Sunoco Logistics had announced its intention to add a second natural gas liquids pipeline to its current Marine East 2 project, raising the total delivery capacity from western Pennsylvania, West Virginia and eastern Ohio to Philadelphia to a potential 675,000 b/d, including the original Mariner East line that is now in service.

Sunoco Logistics is considering expanding the capacity of that first Mariner East 2 pipeline to 450,000 b/d. In addition to the potential expansion of the first pipeline, the company is also looking into constructing a second twin Mariner East 2 pipeline with a 225,000-b/d capacity.

After adding Mariner East 1 at 70,000 b/d, Sunoco Logistics could have as much as 745,000 b/d of pipeline capacity for delivering NGL from the Marcellus region to the Northeast.