The Federal Energy Regulatory Commission on July 9 released an environmental assessment from its staff on impacts for Texas Eastern Transmission LP on its overlying gas pipelines of longwall mining at the Emerald mine of Alpha Natural Resources (NYSE: ANR).
Emerald is a major producer of high-sulfur, Pittsburgh-seam coal, with most of its production through longwall mining. A longwall shears coal from a mine face and its overhead supports crawl forward as that mining is done, leaving the area behind the longwall shields to collapse into the mined-out void through something called subsidence. That can damage overlying gas pipelines.
The mining that will impact the Texas Eastern pipelines is coming up in Greene County, Pa. “The proposal involves mitigation activities to facilitate longwall coal mining beneath multiple existing pipelines owned and operated by Texas Eastern,” the assessment said. “The assessment of the environmental impacts is an important and integral part of the Commission’s decision on whether to issue Texas Eastern a Certificate of Public Convenience and Necessity (Certificate) to excavate, elevate, replace and/or abandon by removal certain sections of various pipelines in two areas to facilitate mining.”
In October 2013, Texas Eastern filed an application with the commission for the Emerald Longwall Mine Panel D1 Project. An EA was prepared and issued for the Emerald Longwall Mine Panel D1 Project on Jan. 27 and the commission issued an order issuing the certificate and approving abandonment on Jan. 29.
On April 4, Texas Eastern filed an amended application with the commission for the Emerald Longwall Mine Project Amendment, because Texas Eastern was notified that Alpha’s Emerald Coal Resources LP now plans to mine its adjacent Panel D2 in the near future. This July 9 EA supplements the January 2014 EA for the Emerald Longwall Mine Panel D1 and focuses on Panel D2 project impact.
Texas Eastern proposes to begin pipeline maintenance and elevation activities as soon as possible in July 2014 to complete the mitigation prior to the heating season. Pipelines would remain in service while aboveground following an approximate four-month construction period and then monitored during the period of potential ground subsidence. Reburial of the pipelines below grade would begin in June 2015, after the anticipated cessation of any ground subsidence. Texas Eastern expects to complete the project and return all pipeline segments to service by Oct. 31, 2015.
U.S. Mine Safety and Health Administration data shows that the Emerald mine produced 987,660 tons in the first quarter of this year and 3.6 million tons in all of 2013.