U.S. DOT/PHMSA - Letter of Decision

Page 1U.S. Department of Transportation 1200 New Jersey Avenue, SE Washington, D.C. 20590 Materials Safety Pipeline and Hazardous Administration Mr. Christopher A. Helms APR 1 3 2010 Executive Vice President and Group CEO NiSource Gas Transmission & Storage 5151 San Felipe, Suite 2500 Houston, Texas 77056 Docket No. PHMSA-2008-0330 Dear Mr. Helms: On November 13, 2008, Columbia Gulf Transmission Company (Columbia Gulf) wrote to the Pipeline and Hazardous Materials Safety Administration (PHMSA) requesting a special permit to waive compliance from PHMSA's pipeline safety regulation in 49 CFR § 192.611, for two segments of the Columbia Gulf natural gas transmission pipeline system in Wilson County, Tennessee. The regulation requires confirmation or revision of the maximum allowable operating pressure (MAOP) of a pipeline segment where the class location has changed. PHMSA is granting this special permit (enclosed), which allows Columbia Gulf, operated by NiSource Gas Transmission & Storage, to operate the 30-inch Mainline 200 and the 36-inch Mainline 300 natural gas transmission pipelines, at their current MAOP's of 1008 pounds per square inch gauge (psig). This special permit provides relief from the Federal pipeline safety regulations for the Mainline 200 and the Mainline 300 pipelines, and requires Columbia Gulf to comply with certain conditions and limitations designed to maintain pipeline safety. PHMSA grants this special permit based on the findings set forth in the "Special Permit Analysis and Findings" document. This document can be read in its entirety in Docket No. PHMSA-2008-0330, in the Federal Docket Management System (FDMS), located on the internet at www.Regulations.gov. My staff would be pleased to discuss this special permit or any other regulatory matter with ou. John Gale, Director of Regulations (202-366-0434), may be contacted on regulator natters and Alan Mayberry, Deputy Associate Administrator for Pipeline Safet (202-366-5124), may be contacted on technical matters specific to this special permit. Sincerely, = Siese Jeffrey D. Wiese Associate Administrator for Pipeline Safety Enclosure (Special Permit)#